Infectious diseases of the skin1) The causative organism for Brucellosis is which of the following:

A. Acid fast bacilli

B. Gram positive cocci

C. Gram negative rodCorrect Choice

D. Gram positive rod

E. Gram negative cocci

Brucella species which cause Brucellosis are gram negative rods. Brucellosis, aka undulant fever, is characterized by an acute febrile illness with headache and joint pain. CNS and cardiac manifestations can also occur. It is acquired by contact with infected animals or contaminated dairy products. Treatment is with doxycycline and rifampin

2) What is the most likely diagnosis of this lesion occurring on the hand of a butcher?

A. Heck's disease

B. Butcher's wart

C. Contagious ecthymaCorrect Choice

D. Molloscum contagiosum

E. Ecthyma gangrenosum

Contagious ecthyma, or orf, occurs most frequently among shepherds and butchers as it is a viral disease that is more common among sheeps and goats. It is caused by a farmyard pox, which also cause Milker's nodules. The lesions tend to heal spontaneously after several weeks

3) For which of the following smallpox vaccination complications is the administration of vaccine immune globulin indicated?

A. Vaccinia keratitis

B. Mild generalized vaccinia

C. Post-vaccinal encephalitis

D. Eczema vaccinatumCorrect Choice

E. Erythema multiforme

Vaccinia immune globulin can be administered to treat some of the complications associated with vaccinia vaccination. Vaccinia immune globulin is indicated for inadvertent inoculation with extensive involvement or ocular implantations, eczema vaccinatum, generalized vaccinia (severe or

1

recurrent), and progressive vaccinia. It is not recommended for inadvertent inoculation with mild reaction, generalized vaccinia (mild or limited), post-vaccination encephalitis, and isolated vaccinia keratitis

4) What characteristic color is seen on diascopy of this lesion?

A. Coral red

B. Orange

C. Blue

D. Red

E. Apple jellyCorrect Choice

Leishmaniasis recidivans is a type of Old World leishmaniasis. Clinically, it appears as a red papule covered with white scale. On diascopy, it has a characteristic apple jelly color

5) Measles is caused by a:

A. Togavirus

B. Rhabdovirus

C. Picornavirus

D. ParamyxovirusCorrect Choice

E. Adenovirus

The measles virus is an RNA virus belonging to the Paramyxovirus family

6) Contagious pustular dermatitis (Orf) is caused by a:

A. Poxvirus Correct Choice

B. Gram-positive spore-forming rod

C. Papovavirus

D. Herpesvirus

E. Paramyxovirus

Orf is caused by orf virus (OV), a poxvirus of the genus Parapoxvirus

7) Butcher's warts are caused by which human papilloma virus (HPV) type?

2

A. 7Correct Choice

B. 2

C. 5

D. 3

E. 13

Butcher's warts are caused by HPV type 7

8) An 18-year old man presents to the Dermatology Clinic with a nontender penile erosion that has been present for 2 weeks. An indurated border and nontender bilateral inguinal lymphadenopathy are also noted. What is the most likely diagnosis?

A. Lymphogranuloma venereum

B. Herpes simplex

C. Chancroid

D. Primary syphilisCorrect Choice

E. HIV

A painless chancre with an indurated border is characteristic of primary syphilis. Associated painless lymphadenopathy ("buboes") is also a common feature

9) What is the causative agent of this parasitic eruption which also causes patchy pulmonary infiltrate and eosinophilia?

A. Filariasis

B. Dracunculiasis

C. Larva migransCorrect Choice

D. Larva currens

E. Gnathostomiasis

Larva migrans is caused by Ancylostoma braziliense, a hookworm of cats and dogs. It also associated with Loeffler's syndrome, patchy infiltrate of the lungs with eosinophilia. Treatment for this parasitic infection is ivermectin or albendazole

10) One of your colleagues returned from a vacation to India with fever, vomiting, pleural effusions, ascites and conjunctival petechiae. She also has a diffuse macular rash with notable areas of sparing that your attending refers to as “white islands in a sea of red”. What is your diagnosis?

3

A. Malaria

B. Leishmania

C. Leptospirosis

D. Typhoid

E. Dengue hemorrhagic feverCorrect Choice

Dengue fever is caused by an Arbovirus and transmitted by the mosquito, Aedes aegypti and may cause Dengue Shock Syndrome and Dengue Hemorrhagic Fever. The infection starts with sudden onset of high fever, backache, retroorbital pain, bone and joint pain, depression and malaise. The disease is also called "break-bone fever." One to seven days after onset of fever, rash presents characteristically starting on the dorsum and hands and feet spreading to limbs and torso. The eruption may become confluent with small, round islands of sparing, the so called "white islands in a sea of red." Treatment is generally supportive as no antivirals are effective

11) The treatment of choice for acyclovir-resistant herpes simplex virus infection is:

A. Saquinivir

B. Valcyclovir

C. Indinivir

D. FoscarnetCorrect Choice

E. Famciclovir

Foscarnet directly inhibits viral DNA polymerase (without requiring phosphorylation by TK) and is therefore effective in acyclovir-resistant HSV infections. Cidofovir can also be used

12) Tricomycosis axillaris is caused by:

A. Burkholderia mallei

B. Corynebacterium tenuis Correct Choice

C. Proteus species

D. Micrococcus sedentarius

E. Corynebacterium minitissimum

Corynebacterium tenuis

13) Which of the following are inconsistent with the diagnosis of staphylococcal scalded skin syndrome?

4

A. Prognosis is good in children with low mortality when anitbiotics are administered early

B. Swabs and cultures of fluid filled blisters overwhelmingly grow staphCorrect Choice

C. Initial event is usually a localized staph infection

D. Cell necrosis does not occur in staphylococcal scalded skin syndrome as it does in T.E.N

E. Epidermal changes are produced by exfoliative toxins of staphlococcus

Staphylococcal scalded skin syndrome: Lesions extend far beyond areas of actual staphylococcal infection, by action of the epidermolytic exotoxin elaborated by the staphylococcus in remote sites. Usually the staphylococci are present at a distant focus such as the parynx, nose ear, or conjuctiva. If cultures are taken they should be obtained fromthe mucous membranes because the skin erythema and desquamation is due to the distant effects of the exfoliative toxin, unlike the sitaution in bullous impetigo, where S. aureus is present in the lesions. Epidermal changes are produced by exfoliative toxins of Staphylococcus. Inital event is usually a localized Staph infection. Prognosis is good in children with low mortality when anitbiotics are administered earyl. Cell necrosis does not occur in SSS as it does in toxic epidermal necrolysis

14) Which of the following is the vector for Dengue fever?

A. Lutzomyia verrucarum

B. Phlebotomus papatasii

C. Xenopsylla cheopis

D. Aedes aegyptiCorrect Choice

E. Culex mosquito

Dengue fever also known as "break-bone" fever is characterized by sudden high fever, backache, retro-orbital pain, bone/joint pain, weakness, and malaise. It is caused by an arbovirus (RNA virus) which is transmitted by Aedes aegypti, a species of mosquito

15) Which virus is most commonly associated with oral hairy leukoplakia?

A. Human papilloma virus

B. Epstein-Barr virusCorrect Choice

C. Parvovirus

D. Pox virus

E. Herpes virus

Oral hairy leukoplakia is an oral mucosal infection most often caused by the Epstein-Barr virus, which occurs in immunocompromised patients. Clinically, thick, white plaques are noted on the lateral sides of the tongue, often fissured

5

16) Which Rickettsial infection has a negative Weil-Felix test?

A. Rickettsialpox (R. akari)Correct Choice

B. Rocky Mountain Spotted Fever (R. rickettsii)

C. Epidemic typhus (R. prowazekii)

D. Mediterranean fever (R. conorii)

E. Endemic typhus (R. typhi)

Rickettsia are short, gram-negative rods which are strict intracellular parasites. The bacteria is transmitted via tick which much be attached for more than 6 hours. The Weil-Felix test exploits cross-reactivity between the Proteus vulgaris antigen and RIckettsia

17) A pool worker develops these painful erythematous nodules with ulceration on his fingers and then his arms. The antibiotic of choice to treat this infection is:

A. Ceftriaxone

B. Trimethoprim-sulfamethoxasole

C. MinocyclineCorrect Choice

D. Dapsone

E. Penicillin

Sporotrichoid spread may be seen in cutaneous leishmaniasis, actinomycosis, atypical mycobacterial infections, deep fungal infection, and melanoma. Mycobacterium marinum is associated with skin injury followed by exposure to contaminated water, usually from an aquarium, lake, or pool. The treatment of choice for M. marinum infections is minocycline

18) A 20-month old child develops a high fever followed 2 days later by a sudden eruption of rose pink macules and papules with white halos as the fever subsides. What is the most likely diagnosis?

A. Measles

B. Rubella

C. Exanthem Subitum Correct Choice

D. Erythema infectiosum

E. Scarlet fever

The cutaneous features of Exanthem Subitum (Roseola infantum, Sixth Disease)as described in the question develop as the fever subsides. While the other diagnoses are part of the differential diagnosis of "fever and rash" in children, only roseola infantum has this characteristic clinical course

6

19) WHO recommendations for the treatment of multibacillary leprosy include all of the following EXCEPT:

A. Clofazimine

B. All of these answers are recommended for the treatment of multibacillary leprosy.

C. Rifampin

D. Dapsone

E. ClarithromycinCorrect Choice

Clarithromycin is not part of the WHO recommendations for the treatment of multibacillary leprosy

20) The most likely cause of the childhood infection shown is:

A. E. coli

B. Pseudomonas Aeruginosa

C. Group A Streptococcus Correct Choice

D. S. Aureus

E. H. influenza

This is an example of perianal streptococcal “cellulitis.” The causative organism is Group A streptococcus

21) In addition to Kaposi’s sarcoma, HHV-8 infection is also the causative agent in:

A. Pyogenic granuloma

B. Pityriasis rosea

C. Angiosarcoma

D. Primary effusion lymphomaCorrect Choice

E. Bacillary angiomatosis

Human herpes virus 8 is a double stranded DNA virus. It is thought to be pathogenic in Kaposi’s sarcoma, primary effusion lymphoma, and Castleman’s disease. Primary effusion lymphoma is a rare B-cell lymphoma seen predominantly in patients with AIDS

22) The nonvenereal treponematosis shown is caused by which of the following organisms?

A. T. pertenue

7

B. T. pallidum (subsp. endemicum)

C. B. duttonii

D. T. carateum Correct Choice

E. T. pallidum

The depigmented patches on the hands shown are characteristic of the late (tertiary) stage of pinta. The causative organism is T. carateum

23) A 52 year-old butcher presents with a tender lesion on his left hand as shown. The treatment of choice for this condition is:

A. Chloramphenicol

B. Ciprofloxacin

C. Tetracycline

D. Penicillin Correct Choice

E. Azithromycin

The clinical description and lesion shown in the image suggest a diagnosis of erysipeloid, caused by Erysipelothrix rhusiopathiae. The treatment of choice is penicillin

24) The treatment of choice of cat-scratch disease is:

A. Itraconazole

B. Mebendazole

C. Ceftriaxone

D. Trimethoprim-sulfamethoxazole

E. ErythromycinCorrect Choice

Cat-scratch disease is caused by Bartonella henselae, which is spread among cats by fleas. The hallmark of the disease is unilateral and regional lymphadenopathy. The treatment of choice for cat-scratch disease is erythromycin

25) Pretibial fever is caused by:

A. Listeriosis

B. Rickettsiae spp.

8

C. LeptospirosisCorrect Choice

D. Rickettsiae spp.

E. Ehlichiosis

Leptospira autumnalis causes pretibial fever (“Fort Bragg fever” or anicteric leptospirosis), an acute exanthematous infectious erythema, generally most prominent on the shins. Leptospira interrogans, serotype icterohaemorrhagiae, is the most common cause of Weil’s disease or icteric leptospirosis

26) Guarneri bodies are associated with:

A. Smallpox Correct Choice

B. Anthrax

C. Measles

D. Orf

E. CMV

Guarnieri’s bodies are cytoplasmic eosinophillic inclusions found on light microscopy

27) Petechial lesions at the junction of the hard and soft palate are characteristically seen in which disease?

A. Kawasaki’s disease

B. Infectious mononucleosisCorrect Choice

C. Scarlet fever

D. Rocky Mountain spotted Fever

E. Rickettsialpox infection

Forsheimer spots are distinctive pinhead size petechiae found at the junction of the hard and soft palate. They may be seen in infectious mononucleosis

28) Congenital Varicella Syndrome occurs after maternal varicella infection during which stage of pregnancy?

A. Third trimester

B. First 20 weeks Correct Choice

C. 20-24 weeks

9

D. 5 days before and 2 days after delivery

E. None of these answers are correct

Congenital Varicella Syndrome occurs after maternal varicella-zoster virus infection early in pregnancy (up to 20 weeks gestation)

29) Of the choices listed, which antiobiotic is the best to treat a 7-year old child with erythema migrans?

A. Tetracycline

B. Azithromycin

C. AmoxicillinCorrect Choice

D. Doxycycline

E. Rifampin

Doxycycline is the usual treatment for erythema migrans in adults in the absence of neurologic or cardiovascular complications. In children less than 8, all tetracyclines are relatively contraindicated because of they can cause tooth discoloration. Therefore amoxicillin should be used as the first line therapy for children less than 8. Note: Changes have been made to the treatment of RMSF. Children of any age should be treated with doxycycline for that disease

30) A 48 year-old woman presents to the Emergency Room with a 2 day history of fever and a well demarcated erythematous plaque on her right cheek. What is the treatment of choice?

A. Potent topical corticosteroid

B. Fluconazole

C. Intravenous penicillinCorrect Choice

D. Prednisone

E. Cephelexin

The most likely diagnosis is Erysipelas which is caused by beta-hemolytic group A streptococcus. The treatment of choice is intravenous penicillin

31) Herpes simplex virus infection and this condition has been linked to which HLA type?

A. HLA B15Correct Choice

B. HLA B51

C. HLA DR3

10

D. HLA Cw6

E. HLA B27

HSV related erythema multiforme has been associated with an increased frequency of HLA-B15

32) Milker’s nodule is caused by infection with which of the following viruses?

A. Orf virus

B. Human herpesvirus-8 (HHV-8)

C. Paravaccinia virusCorrect Choice

D. Human herpesvirus-6 (HHV-6)

E. Vaccinia virus

Milker’s nodule is caused by paravaccinia virus, a poxvirus of the genus Parapoxvirus. It is transmitted to humans from infected cows

33) Which porphyrin is responsible for the fluorescence under Wood's lamp examination of erythrasma?

A. Protoporphyrin IX

B. Porphobilinogen

C. Coproporphyrin IIICorrect Choice

D. Coproporphyrinogen

E. Uroporphobilinogen

Erythrasma is caused by corynebacterium minutissimum. The presence of coprophyrinogen III created by the bacteria is responsible for the characteristic coral-red fluorescence under Wood's lamp

34) Epithelioma cuniculatum is an HPV-associated verrucous carcinoma involving the:

A. Trunk

B. Scalp

C. Penis

D. Oral mucosa

E. SoleCorrect Choice

11

Epithelioma cuniculatum is a form of verrucous carcinoma involving the sole

35) A 28 year-old man presents with fever, chills, arthralgias and the cutaneous lesions shown. The most likely diagnosis is:

A. Gonoccemia Correct Choice

B. Rickettsialpox

C. Primary herpes simplex infection

D. Anthrax

E. Purpura fulminans

The image shows sparsely distributed hemorrhagic vesiculopustules with erythematous bases on an acral surface. These features are characteristic of gonococcemia

36) Blueberry Muffin Baby can be a feature of all of the following EXCEPT:

A. Rhabdomyosarcoma

B. Langerhans’ cell histiocytosis

C. TORCH

D. Hemolytic disease of the newborn

E. Klippel-Trenaunay-Weber syndrome Correct Choice

Blueberry muffin lesions can be seen in the setting of prenatal infections (e.g. TORCH), severe anemia (e.g. Hemolytic Disease of the newborn) and neoplastic diseases (e.g. rhabdomyosarcoma). It is not associated with the Klippel-Trenaunay-Weber syndrome

37) The treatment of choice for Oroya Fever is:

A. ChloramphenicolCorrect Choice

B. Erythromycin

C. Penicillin

D. Minocycline

E. Doxycycline

The treatment of choice for Oroya Fever is chloramphenicolbecause of frequent superinfection withSalmonella

12

38) A 10 year-old with a 3-day history of fever and headache presents to the clinic with multiple erythematous papulopustules on his extremities, many of which have central eschars. The most likely diagnosis is:

A. Erlichiosis

B. RickettsialpoxCorrect Choice

C. Meningococcemia

D. Lyme disease

E. Rocky mountain spotted fever

Rickettsialpox is an acute febrile illness caused by the bacteria Rickettsia akari, a member of the spotted fever group. R. akari is transmitted by the house mouse mite, Liponyssus sangineus. Clinically, patients have an eschar at the inoculation site with a subsequent papulovesicular rash, fevers, headache, chills, diaphoresis, myalgia, and anorexia

39) A 35 year-old woman presents with a painful vaginal erosion and tender left-sided inguinal lymphadenopathy. Gram stain reveals clusters of coccobacilli in a “school of fish” pattern. What is the most likely diagnosis?

A. Granuloma inguinale

B. ChancroidCorrect Choice

C. Primary syphilis

D. Secondary syphilis

E. Lymphogranuloma venereum

Chancroid classically presents with a soft, tender chancre with ragged edges and unilateral, tender inguinal adenopathy (bubo). A “school of fish” pattern on Gram or Giemsa stain is diagnostic

40) All of the following are features of scarlet fever except:

A. S. aureus infectionCorrect Choice

B. Pastia’s lines

C. Pharyngitis

D. Circumoral pallor

E. Sandpaper-like texture

Scarlet fever is primarily a disease of children with most cases occurring between the ages of 1 and 10 years of age. Streptococcus pyogenes is the causative organism. It produces the streptococcus pyrogenic exotoxin which elicits the cutaneous manifestations by enhancing delayed type

13

hypersensitivity to streptococcal products. Clinical findings include fever, sore throat, headache, chills, sandpaper rash on the trunks, strawberry tongue, and Pastia’s lines (linear petechial streaks found in flexural locations

41) Hebra nose deformity is characteristic of infection with which organism?

A. Serratia marcesens

B. Haemophilus influenzae

C. Streptococcus pyogenes

D. E. coli

E. Klebsiella pneumoniaeCorrect Choice

Hebra nose deformity is seen in Rhinoscleroma which is caused by Klebsiella pneumoniae

42) Pediculus humanus corporis can transmit:

A. Scrub typhus

B. Oriental typhus

C. Epidemic typhusCorrect Choice

D. Endemic typhus

E. Murine typhus

The body louse or Pediculus humanus corporis transmits Rickettsia prowasekii the organism responsible for epidemic typhus. Endemic typhus or murine typhus is caused by R. typhi that is transmited by the rat flea/Xenopsylla cheopis. Scrub typhus is caused by R. tsutsugamushi and is transmitted by chiggers or trombiculid mite larvae

43) Xenopsylla cheopis transmits:

A. Rickettsia akari

B. Epidemic typhus

C. Scrub typhus

D. Murine typhusCorrect Choice

E. Rickettsia prowazekii

Xenopsylla cheopis along with Ctenocephalides felis are fleas that transmit R. typhi, the organism responsible for murine or endemic typhus. The body louse or Pediculus humanus corporis transmits Rickettsia prowasekii the organism responsible for epidemic typhus. Scrub typhus is caused by R. tsutsugamushi and is transmitted by chiggers or trombiculid mite larvae

14

44) A 4 year-old boy is diagnosed with Staphylococcal Scalded-Skin Syndrome. Vesiculation in this disease is secondary to exfoliative toxins binding what target protein?

A. Desmoglein 1Correct Choice

B. Bullous Pemphigoid antigen 1

C. Bullous pemphigoid antigen 2

D. Desmoglein 3

E. Plectin

Staphylococcus Scalded-Skin Syndrome (SSSS) is caused by Staphylococcus exfoliative toxins A and B binding desmoglein A. This results in the intraepidermal split at the granular layer seen in this illness. Targeting of desmoglein 3 would result in a suprabasilar split. Targetting of plectin, BPAG1, or BPAG2 would result in a subepidermal split. This is not seen in SSSS

45) Streptococcus Iniae has been shown to cause:

A. Perianal dermatitis in neonates

B. Bullous impetigo

C. Perineal erysipelas in postpartum women

D. Necrotizing fasciitis

E. Hand cellulitis in fish handlersCorrect Choice

Streptococcus iniae has been demonstrated to cause hand cellulitis from puncture wounds sustained form the dorsal fin, fish bone or knife of usually a tilapia. Treatment with PCN is curative. Group A Streptococci are the most common cause of perianal dermatitis. Many different bacteria have been implicated in necrotizing fasciitis. Bullous impetigo is most frequently caused by phage type 71 S. aureus or a related group 2 phage type. Group B streptococcus is most often responsible for perineal erysipelas in postpartum women.

46) What is the most common site of infection from Streptococcus Iniae?

A. Face

B. HandCorrect Choice

C. Lower leg

D. Foot

E. Nails

15

Streptococcus iniae most commonly causes bacteremic cellulitis of the hand in persons who have recently handled fresh fish. S. iniae is a fish pathogen that causes sporadic infection in tilapia, yellowtail, rainbow trout, and coho salmon. Treatment of choice is with penicillin antibiotics

47) The vector of New World Leishmaniasis is the:

A. Deer fly (Chrysops spp.)

B. Tsteste fly

C. Phlebotomus sandfly

D. Lutzomyia sandflyCorrect Choice

E. Simulium black fly

The sandfly belonging to the genus Lutzomyia is the vector of New World Leishmaniasis. Sandflies of the genus Phlebotomus are the vectors of Old World Leishmaniasis

48) How long is the life cycle for the mite that causes this infestation?

A. 1 day

B. 1 monthCorrect Choice

C. 6 months

D. 1 year

E. 1 week

Scabies is caused by the mite Sarcoptes scabiei var. hominis. The life cycle of the mite is 30 days. A female mite will lay 60-90 eggs during her life

49) Herpes-associated erythema mutliforme is most commonly associated with which HLA type?

A. HLA DR2

B. HLA DR3

C. HLA B15Correct Choice

D. HLA B8

E. HLA B27

Recurrent erythema multiforme (EM minor) is usually caused by recurrent herpes simplex, most commonly HSV-1 orolabial disease. This is more correctly now called herpes-associated erythema multiforme(HAEM) and has been more commonly associated with people with HLA type B15

50) All of the following are features of the Ramsay Hunt Syndrome EXCEPT:

16

A. Infection of the geniculate ganglion

B. Vesicles on the external ear

C. Tinnitus

D. Facial paresis

E. Herpes simplex infectionCorrect Choice

Ramsay Hunt syndrome results from varicella zoster virus infection of the geniculate ganglion of the seventh cranial nerve (CN VII). It is characterized by vesicles on the external ear or ear canal, tinnitus and/or other auditory symptoms, and ipsilateral facial paresis

51) Exanthem Subitum is caused by which of the following?

A. Group A Steptococcus

B. Coxsackie virus

C. Human Herpes Virus-6 (HHV-6) Correct Choice

D. Parvovirus B19

E. Epstein-Barr Virus

Exanthem Subitum (Roseola Infantum, Sixth Disease) is caused by human herpesvirus 6, and 7 (HHV-6, HHV-7

52) Carrion's disease is characterized by fevers, headaches and arthralgias and is accompanied by severe hemolytic anemia. Superinfection with which organism is the most frequent cause of death?

A. Shigella

B. Bartonella henselae

C. SalmonellaCorrect Choice

D. Bartonella bacilliformis

E. Bartonella Quintana

Carrion's disease (Oroya fever) is characterized by fevers, headaches and arthralgias and is accompanied by severe hemolytic anemia. Superinfection with Salmonella is the most frequent cause of death. Protection from sandfly bites is all-important

53) Dracunculiasis is typically acquired from:

A. Soil

17

B. Salt water

C. Black flies

D. Drinking water Correct Choice

E. Chiggers

Dracunculiasis, which is caused by Dracunculus medinensis, is acquired by ingestion of copepod-infested water

54) Which subtype of the human papilloma virus is most likely to have caused this infection?

A. HPV, type 3

B. HPV, type 6Correct Choice

C. HPV, type 1

D. HPV, type 5

E. HPV, type 2

The human papilloma virus is a member of the Papovavirus family, a double-stranded DNA virus. HPV, type 6 has been implicated in giant conduloma of Buschke and Lowenstein and anogenital condyloma

55) Which of the following diseases is caused by a virus?

A. Boutonneuse spotted fever

B. Colorado tick feverCorrect Choice

C. Q fever

D. Rocky Mountain spotted fever

E. Human monicytic ehrlichiosis

Rocky Mountain spotted fever is caused by Rickettsia rickettsii. Human monicytic ehrlichiosis is caused by Ehrlichia chaffeensis. Colorado tick fever is caused by Reoviiridae. Boutonneuse fever is caused by Rickettsia conorii. Q fever is caused by Coxiella burnetti

56) Epidermodysplasia verruciformis is caused by which human papilloma virus (HPV) types?

A. 3 and 10

B. 6 and 11

18

C. 5, 8, and 9Correct Choice

D. 13 and 32

E. 16 and 18

Epidermodysplasia verruciformis is caused by HPV types 5, 8, 9, 12, 14, 15, 17, 19-26

57) Verruga peruana is transmitted by:

A. Fecal oral contact

B. Blackfly

C. SandflyCorrect Choice

D. Tick

E. Fecal fecal contact

Verruga peruana, a disease endemic to Peru and a few neighboring countries, is caused by Bartonella bacilliformis. It is transmitted by the sandfly, Lutzomyia verrucarum. It is preceded by an acute febrile stage called Oroyo fever or Carrion’s disease. The treatment of choice is chloramphenicol

58) Each of the following is true regarding leishmaniasis except:

A. Arthropod vector is the sand fly

B. Mazzotti’s test is diagnosticCorrect Choice

C. Cutaneous disease is the most common form

D. Pentavalent antimony used for visceral disease

E. Espundia seen mucocutaneous disease

Leishmaniasis is a parasitic infection born by a sandfly vector. No treatment is necessary for cutaneous leishmaniasis, pentavalent antimony for visceral leishmaniasis. Mazzotti reaction is used to test for onchocerciasis in which a single dose of dimethycarbamazine is given for reaction

59) What is the principal vector of Lyme Disease in the Northeastern U.S.?

A. Lxodes ricinus

B. Dermacentor variabilis

C. Lxodes damminiCorrect Choice

19

D. Ambylomma americanum

E. Soft-bodied ticks (Ornithodoros)

The proncipal vector of Lyme Disease in the Northeastern U.S. is Ixodes dammini (Ixodes scapularis

60) Which of the following mycobacterial organisms is classified as a photochromogen?

A. M. tuberculosis

B. M. grodonae

C. M. KansasiiCorrect Choice

D. M. ulcerans

E. M. fortuitum

M. Kansasii, M. marinum, and M. simiae are photochromogens. They form pigment when exposed to light

61) The vector of Trench Fever is the:

A. Cat flea (Ctenocephalides felis)

B. Human body louse (Pediculus humanus corporis)Correct Choice

C. Trombiculid mite

D. Sandfly (Phlebotamus perniciosus)

E. Rat flea (Xenopsylla cheopis)

The human body louse (Pediculus humanus corporis)is the vector of Trench Fever, Epidemic Typhus, and Relapsing Fever

62) Pediculus humanus var. corporis (human body louse) is the vector in which of the following diseases:

A. Q fever (C. burnetii)

B. Endemic typhus (R. typhus)

C. Rickettsialpox (R. akari)

D. Epidemic typhus (R. prowazekii)Correct Choice

E. Rocky Mountain Spotted Fever (R. rickettsii)

20

The human body louse is the implicated Trench fever, epidemic typhus, and relapsing fever. Trench fever usually affects alcoholic men and is manifested by fevers. Treatment is with ceftriaxone, erythromycin, or doxycycline. Epidemic typhus is manifested by fevers, chills, malaise, and a pink macular eruption beginning in the axilla and trunk. Treatment is with tetracycline or chloramphenicol. Relapsing fever is manifested by paroxysmal fevers, headache, lymphocytoma, and erythematous/petechial macules on trunk/extremities. Treatment is with doxycycline

63) A 27 year-old man with a 1-month history of bilateral inguinal lymphadenopathy and a positive “groove sign.” What is the most likely diagnosis?

A. Gonorrhea

B. Lymphogranuloma venereumCorrect Choice

C. Syphilis

D. Chancroid

E. Herpes simplex

Inguinal adenopathy with fluctuant, tender nodes above and below Poupart’s ligament - referred to as “groove sign” - is a characteristic clinical feature of lymphogranuloma venereum

64) The most common location of herpes gladiatorum is the:

A. FaceCorrect Choice

B. Anterior thigh

C. Groin

D. Hand

E. Chest

The face is the most common location for Herpes Gladiatorum

65) Which of the following is the vector of lymphatic filariasis caused by Wuchereria bancrofti?

A. Black fly

B. Deerfly

C. Mosquito Correct Choice

D. Botfly

E. Tsteste fly

Lymphatic filariasis is spread by mosquitoes belonging to genera Aedes, Anopheles, Culex, or Mansonia

21

66) What is the classic CXR finding of a patient with inhalational anthrax?

A. Pleural effusions

B. Increased interstitial markings

C. Widened mediastinumCorrect Choice

D. Alveolar infiltrates

E. Normal x-ray

Inhalation anthrax is the most lethal form of anthrax. Other forms include cutaneous anthrax and GI anthrax. The classic radiographic finding is a widened mediastinum

67) What is the vector for this nematodal infection?

A. Tsetse fly (Glossine morsitans)

B. Mango fly (Chrysops)Correct Choice

C. Black fly (Simulium)

D. Water flea (Cyclops)

E. Reduviid bug

Loiasis is caused by the nematode loa loa. It is transmitted by the mango fly (Chrysops dimidia or CHrysops silacea). It may manifest with painful, localized subcutaneous nonpitting edema called calabar swellings. Conjunctival migrations are also common

68) A goatherder develops this painless pustule that subsequently forms a black eschar. What causes the edema to form in this lesion?

A. Inhibition of phagocytosis

B. C1 esterase inhibitor

C. Increased levels of cAMPCorrect Choice

D. Release of TNF-alpha

E. Release of IL-1beta

Anthrax is caused by Bacillus anthracis, a gram positive spore-forming rod. Anthrax is primarily seen in individuals who are in contact with wild or domestic animals. Recent cases have been linked with bioterrorism. B. anthracis produces edema toxin and lethal toxin. Edema toxin is comprised of edema factor and protective antigen. Edema factor is a calmodulin dependent adenyl cyclase. The increased cAMP induces the gelatinous edema of anthrax skin lesions

22

69) Which human papillo viurs (HPV) type is implicated in papillomatosis cutis carcinoides di Gottron?

A. 7

B. 11Correct Choice

C. 60

D. 18

E. 57

Papillomatosis cutis carcinoides di Gottron, also know as Gottron's tumor, is a verrucous carcinoma of the skin. In 1948, Ackerman first described verrucous carcinoma (VC), a low-grade tumor that generally is considered a clinicopathologic variant of squamous cell carcinoma.Verrucous carcinomas are caused by HPV types 6 and 11. When they occur on the feet they are called epithelioma caniculatum. When they occur on the genitals they are refered to as Buschke-Lowenstein tumors. When they occur in the mouth they are called Ackerman's tumors or oral florid papillomatosis

70) A 48 year-old man develops headache, myalgias, and high fever 5 days after a hunting trip. On examination he has a tender ulcer with raised margins and an eschar on his index finger, as well as tender axillary lymphadenopathy. The most likely diagnosis is:

A. Orf

B. Anthrax

C. Tularemia Correct Choice

D. Glanders

E. Erysipeloid

Tularemia, which is caused by Francisella tularensis, occurs after exposure to infected animals, including, rabbits, foxes, and squirrels. The clinical description is that of the ulceroglandular form, which is the most common presentation

71) Which exotoxin(s) are involved in mediating the effects of Bacillus anthracis - the causative organism for anthrax?

A. Lethal Toxin

B. Edema Toxin and Lethal ToxinCorrect Choice

C. Exotoxin B

D. Edema Toxin

23

E. Alpha toxin

B. anthracis has 2 exotoxins: edema toxin and lethal toxin, each comprised of a pair of noncovalently linkedproteins:– Edema toxin = Edema Factor (EF) + Protective Antigen (PA)– Lethal toxin = Lethal Factor (LF) + PA– EF causes gelatinous edema of anthrax skin lesions by inducing an increase in cyclic adenosine monophosphate (cAMP) levels– LF causes shock and death in disseminated anthrax via the release of tumor necrosis factor-alpha (TNF-a)and interleukin-1b (IL-1b)– PA is responsible for entry of exotoxins into the cell by receptor-mediated endocytosis

72) A 43 year-old man with uncontrolled HIV disease presents with yellowish, red papules, draining sinuses and ulcers perianally and periurethrally. Which histopathological or immunohistochemical stain may aid in diagnosis?

A. Von Gieson (EVG)

B. CD3

C. Steiner

D. CD20

E. Von KossaCorrect Choice

The most likely diagnosis is malakoplakia. Malakoplakia, an infection usually attributed to S. aureus, P. aeruginosa, or E. coli is characterized histopathologically by Michelis-Gutmann bodies. These are foamy eosinophilic macrophages containing calcified, laminated, intracytoplasmic bodies. They can be highlighted by a calcium stain such as von Kossa. CD3 and CD20 are lymphocyte markers, von Gieson is an elastic tissue stain, and Steiner stain is used to highlight spirochetes. These would not aid in the diagnosis of malakoplakia

73) A 42 year-old woman presents with a large, vegetating ulcer involving her left labia majora and groin for over 1 year. A Giemsa’s stained touch preparation reveals bipolar, safety pin-shaped intracytoplasmic inclusions. What is the most likely diagnosis?

A. Chancroid

B. Lymphogranuloma venereum

C. Gonorrhea

D. Primary herpes simplex

E. Granuloma InguinaleCorrect Choice

Bipolar, safety pin-shaped intracytoplasmic inclusions on Giemsa stain - known as Donovan bodies - are diagnostic of granuloma inguinale

74) The leading infectious cause of deafness and mental retardation in the U.S. is:

24

A. Congenital herpes simplex

B. Congenital syphilis

C. Congenital Cytomegalovirus (CMV)Correct Choice

D. Congenital varicella

E. Congenital Rubella

Congenital CMV is the leading infectious cause of deafness and mental retardation in the U.S.

75) Which human papillomavirus type is associated with giant condylomata of Bushke and Lowenstein (Bushke-Lowenstein tumor)?

A. 2

B. 31

C. 16

D. 1

E. 6 Correct Choice

The Bushke-Lowenstein tumor is caused by HPV-6 and 11

76) Each of the following species may be involved in necrotizing fasciitis except:

A. MycobacteriumCorrect Choice

B. Pseudomonas

C. Bacteroides

D. Streptococcus

E. Clostridium

Necrotizing fasciitis is a rapidly advancing acute necrotizing infection that may follow trauma, surgery, or occur spontaneously. It is associated with systemic toxicity and high mortality rate. Clinically, erythema, edema, and edema progresses to dusky cyanosis, blistering and necrosis. Many virulent bacteria have been culturesd including Pseudomonas, Bacteroides, streptococci, staphylococcus, enterococci, and clostridium. Both aerobic and anaerobic cultures should be taken. Mycobacterium is not associated with necrotizing fasciitis

77) Bacillary angiomatosis is caused by which of the following organisms?

A. B. quintana

25

B. All of these answers are correct

C. B. quintana and B. henselaeCorrect Choice

D. B. bacilliformis

E. B. henselae

B. quintana or B. henselae are both causative organisms for bacillary angiomatosis

78) A 24 year-old man from New York City develops fever, chills, malaise, and a severe headache. His apartment has a mouse problem. On examination, multiple, discrete papulovesicles and a single eschar are found. What is the most likely diagnosis?

A. RickettsialpoxCorrect Choice

B. Rocky Mountain Spotted Fever

C. Q Fever

D. Meningococcemia

E. Ehrlichiosis

The clinical description is that of rickettsialpox, which is caused by R. akari and spread by liponyssoides sanguineus - the house mouse mite

79) Nonmenstrual cases of the staphylococcal toxic shock syndrome are mediated by which of the following toxins?

A. Epidermolytic toxins A and B

B. Edema toxin

C. Pyrogenic exotoxins A, B, C

D. Exfoliative toxins A and B

E. Enterotoxins B and C Correct Choice

Toxic shock syndrome (TSS) is mediated by Enterotoxins B and C (50% of nonmenstrual cases) and TSS toxin 1 (TSST-1), which is the leading cause of menstrual cases

80) A 27 year-old HIV positive presents with this pruritic eruption? What is the characteristic cell type found on histopathology?

A. Plasma Cell

B. Lymphocyte

26

C. Neutrophil

D. EosinophilCorrect Choice

E. Neutrophil

Eosinophilic pustular folliculitis is a pruritic disorder that may be seen in HIV positive patients. Typically, the CD4 count is < 300. In patients with HIV, pruritus tends to improve after institution of anti-retroviral therapy

81) Which of the following statements best describes the pathogenesis of scrofuloderma?

A. Autoinoculation of M. tuberculosis from advanced pulmonary tuberculosis

B. Hematogenous spread of M. tuberculosis from a distant site of infection

C. Primary incoculation of M. tuberculosis in a sensitized host

D. An cutaneous manifestation of military tuberculosis

E. Contiguous spread from an underlying focus of tuberculous lymphadenitis Correct Choice

Scrofuloderma is the result of contiguous spread onto skin from an underlying focus of tuberculous infection. This typically occurs in a sensitized host with low immunity

82) Focal epithelial hyperplasia (Heck’s Disease) is associated with which of the following human papillomavirus types?

A. 7

B. 13 Correct Choice

C. 10

D. 4

E. 3

Focal epithelial hyperplasia is caused by HPV-13 and 32

83) Winterbottom’s sign is a characteristic feature of which of the following diseases?

A. Onchocerciasis

B. Leishmaniasis

C. Loaiasis

D. Strongyloidiasis

27

E. African Trypanosomiasis Correct Choice

Winterbottom’s sign (posterior cervical lymphadenopathy) is a clinical feature of African trypanosomiasis. Romaña’s sign (eyelid edema and conjunctivitis at site of incoculation) is a diagnostic finding in American trypanosomiasis (Chagas’ disease)

84) A young patient presents to you after participating in a bar brawl a few nights before with a painful swollen erythematous right hand. The most likely organism is:

A. Staphylococus aureus

B. Bacteriodes fragilis

C. Eikenella corrodensCorrect Choice

D. Pasturella multocida

E. Streptococcus pyogenes

Eikenella corrodens is a member of normal oral flora, that is commonly the cause of human bite and fist fight infections. Pasturella multocida is a common organism found in dog and cat bites. Staph and Strep could be the right answers for a cellulitis, but with this history are not the correct choices. Baceriodes fragilis is found in normal bowel flora

85) Hutchinson’s teeth are a feature of which stage of syphilis?

A. Primary

B. Secondary

C. Tertiary

D. Early congenital

E. Late congenital Correct Choice

Hutchinson’s teeth (widely-spaced, peg-shaped upper incisors) are a seen in Late Congenital Syphilis (> 2 years of age

86) The causative organism in Whitmore disease is which of the following?

A. Vibrio vulnificus

B. Pseudomonas aeruginosa

C. Streptobacillus moniliformis

D. Burkholderia pseudomalleiCorrect Choice

E. Klebsiella pneumoniae

28

Whitmore disease also known as Meloidosis is characterized by pulmonary disease, septicemia, and miliary abscesses. It is caused by Burkholderia pseudomallei

87) All of the following are true regarding tularemia except:

A. Potential for use as a biologic weapon

B. Ticks serve as a reservoir

C. No longer one of the CDC's list of reportable diseasesCorrect Choice

D. Presents as an acute febrile illness

E. Caused by the gram negative Francisella tularensis

Tularemia is a zoonotic disease caused by the gram-negative coccobacillus Francisella tularensis. It is transmitted by arthropods (particularly tick bites) or from contact with infected mammals (usually rabbits). It characteristically presents as an acute febrile illness with other variable clinical manifestations depending on the route of inoculation. Possible symptoms could include an ulcer at the site of inoculation, pharyngitis, ocular lesions, lymphadenopathy, and pneumonia. Diagnosis can be made by culture or a fourfold titer change. Because of its potential use as a biologic agent, tularemia is once again a reportable disease

88) All of the following are potential causes of a false positive RPR except:

A. Pregnancy

B. Malaria

C. Malignant MelanomaCorrect Choice

D. Systemic Lupus Erythematosus (SLE)

E. Lepromatous Leprosy

Non-treponemal tests for syphilis measure antibodies against phospholipids released from treponemes and damaged host cells. False positive non-treponemal tests can occur in the setting of pregnancy, autoimmune diseases, other spirochete infections, and infectious diseases such as leprosy and malaria. It does not occur in cases of melanoma

89) Coxsackievirus A16 is implicated in the pathogenesis of which of the following dieases?

A. Fifth disease

B. Exanthem subitum

C. Papular purpuric “gloves and socks” syndrome

D. Hand-Foot-and-Mouth disease Correct Choice

29

E. Erythema infectiousum

Hand-Foot-and-Mouth disease is caused by coxsackievirus A16. Group A coxsackievirus infection is also associated with herpangina

90) The most common bacterial cause of purpura fulminans is:

A. Group A streptococcus Correct Choice

B. E. coli

C. P. aeruginosa

D. S. aureus

E. H. influenzae

Group A streptococcus is the leading bacterial cause of purpura fulminans

91) Which of the following is the causative organism of Tularemia?

A. Orientia tsutsugamushi

B. Klebsiella pneumoniae

C. Burkholderia mallei

D. Francisella tularensisCorrect Choice

E. Streptobacillus moniliformis

Tularemia is caused by infection with Francisella tularensis - most commonly acquired after contact with infected rabbits (e.g. hunters

92) Roseola infantum is caused by which virus?

A. Pox virus

B. Coxsackie virus A16

C. Parvovirus B19

D. Human herpes virus 6Correct Choice

E. Epstein-Barr virus

Roseola infantum may be cause be either human herpes virus types 6 or 7. It is the sixth of the traditional exanthems of childhood. A diffuse, maculopapular eruption is typically preceded by a prodrome of fever and either respiratory or gastrointestinal symptoms. The infection usually occurs in the spring and the fall and nearly all children are seropositive for the virus by the age of 4

30

93) Foamy macrophages containing Klebsiella pneumoniae are called:

A. Mikulicz's cellsCorrect Choice

B. Virchow cells

C. Michaelis-Gutman cells

D. Russell cells

E. Hansemann's cells

Mikulicz’s cells are foamy macrophages found in Rhinoscleroma – a chronic, inflammatory, granulomatous disease of the upper respiratory tract. Virchow cells are found in Hansen’s disease. Hansemann cells and Michaelis-Gutman bodies are found in Malakoplakia

94) The diagnosis of leishmaniasis can be confirmed by which of the following techniques?

A. Culture in Sabourad's agar

B. Warthin-Starry stain

C. Culture in Michel's medium

D. Weil-Felix test

E. Culture in Novy-MacNeal-Nicolle (NNN) mediumCorrect Choice

Confirmation of infection with Leishmaniasis is performed by culture in Novy-MacNeal-Nicolle (NNN) medium

95) What is the most common cause of focal epithelial hyperplasia?

A. Pachyonychia Congenita

B. human immunodeficiency virus(HIV)

C. Dyskeratosis Congenita

D. human papilloma virus(HPV)Correct Choice

E. Ebstein Bar virus(EBV)

Focal epithelia hyperplasia, also known as Heck's disease, is caused by HPV types 13, 32 and 57. It is most commonly found on the lower lip but also on the buccal mucosa, gums and tongue. It is mainly a disease of native Americans and Greenlander Eskimos. EBV causes an oral hairy leukoplakia in patients with AIDS. Pachyonychia Congenita patients commonly develop a benign oral leukoplakia, while Dykeratosis Congenita patients develop a premalignant oral leukoplakia

96) Which form of cutaneous tuberculosis is associated with the highest level of immunity?

31

A. Tuberculosis gumma

B. Tuberculosis verrucosa cutis

C. Lupus vulgarisCorrect Choice

D. Miliary tuberculosis

E. Tuberculosis chancre

Lupus vulgaris is an chronic, progressive form which usually occurs around nose, neck and earlobes, notable for gelatinous "apple-jelly" hue. Tuberculosis chancre and tuberculosis verrucosa cutis cutis are primary inoculations of tuberculosis infection. Tuberculosis gumma and miliary tuberculosis are associated with lowered states of immunity

97) Which of the following is the causative organism of cat-scratch disease?

A. B. quintana

B. B. burgdorferi

C. B. bacilliformis

D. B. henselae Correct Choice

E. B. duttonii

B. henselae is the cause of cat-scratch disease. Humans are infected by a cat bite or scratch, while the cat flea is responsible for cat to cat transmission

98) Herpangina is caused by which of the following?

A. Parvovirus B19

B. Group A coxsackievirusCorrect Choice

C. Human Herpesvirus 6 (HHV-7)

D. Epstein Barr Virus

E. Human Herpesvirus 6 (HHV-6)

Herpangina is caused by Group A coxsackievirus

99) A patient on the bone marrow transplant service has a fever, neutropenia, hemorrhagic bullae and erythematous nodules with dusky gray centers. The organism most likely to be responsible is:

A. Streptococcus pyogenes

32

B. Pseudomonas aeruginosaCorrect Choice

C. Mycobacterium tuberculosis

D. Staphylococcus aureus

E. Candida albicans

Ecthyma gangrenosum is an infection of critically ill or immunocompromised individuals by Pseudomonas aeruginosa. Clinically, patients develop opalescent, tense vesicles or pustules surrounded by a narrow pink to violaceous halo. The lesions rapidly become hemorrhagic, then violaceous and necrotic leaving ulcers. The most common location is on the buttocks and lower extremities. Treatment is with aminoglycosides

100) What is the treatment of choice in a penicillin allergic individual?

A. Rifampiin

B. Penicillin

C. DoxcycylineCorrect Choice

D. Ceftriaxone

E. Clindamycin

Secondary syphillis is caused by the spirochete, T. pallidum. Penicillin is the treatment of choice for secondary syphillis. In penicillin allergic individuals, doxycyline may be used

101) A patient presents with this anesthestic plaque. Which cytokines are upregulated in this disease?

A. IL-2Correct Choice

B. All of these cytokines are upregulated

C. IL-5

D. IL-10

E. IL-4

Leprosy is caused by infections to Mycobacterium leprae. It is a acid fast bacilli. In tuberculoid leprosy, Th1 cytokines (IL-2, IFN-gamma) are upregulated. Clinically, patients have few, well-circumscribed anesthetic plaques

102) A 43 year-old man presents with suppurative nodules and sinus tracts over the mandible. He also is noted to have poor oral hygiene. What is the most likely causative organism?

A. Staphylococcus aureus

33

B. Nocardia brasilensis

C. Streptococcus somaliensis

D. Bartonella Henselae

E. Actinomyces israeliiCorrect Choice

Actinomyces israelii is an anaerobic gram-positive rod which causes chronic suppurative nodules and sinus tracts with an exudate containing sulfur granules. It most commonly effects the cervicofacial area, especially near the mandible. The abdomen and thoracic areas can also be affected. The source of infection is endogenous and patients with poor oral hygiene, penetrating foreign bodies, and recent dental procedures are at increased risk. Treatment of choice is penicillin

103) A 32 year-old woman presents with meningitis and palpable purpura. A diagnosis of meningococcemia is confirmed via culture of cerebrospinal fluid. Which complement components are most likely to be deficient in this patient?

A. C3

B. C2

C. C4

D. C5Correct Choice

E. C1

Patients with meningococcemia often demonstrate deficiencies of late complement components C5-9.

104) A 62 year-old man presents with tinnitus, facial paralysis, and vesicles of the external ear. What is the most likely diagnosis?

A. Primary Herpes Simplex infection

B. Coxsackievirus A16 infection

C. Cytomegalovirus infection

D. Primary Varicella Infection

E. Herpes Zoster InfectionCorrect Choice

This patient has Ramsay Hunt Syndrome, herpes zoster infection of the geniculate ganglion. Vesicles can be seen on the tympanic membrane and the external ear. Symptoms include ipsilateral facial paralysis, tinnitus, or other auditory symptoms. Treatment is with acyclovir and systemic corticosteroids

105) Calabar swellings are a characteristic feature of which disease?

34

A. Eumycetoma

B. LoiasisCorrect Choice

C. Carrion's Disease

D. Tertiary Syphilis

E. Onchocerciasis

Calabar swellings are characteristic of Loiasis. They are transient, non-tender soft tissue swellings found most commonly around joints

106) What is the characteristic body on histopathology for this disease?

A. Henderson-Patterson

B. Cowdry Type ACorrect Choice

C. Dutcher

D. Guarnieri

E. Cowdry Type B

Herpes simlex virus is characterized by Cowdry type A bodies on histopathology. They appear as sharply demarcated eosinophilic structures separated by a clear halo from a basophilic rim of the infected cell's marginated nuclear chromatin. Cowdry B bodies may be seen in polio infections

107) A 10 year-old girl presents to the dermatology clinic with a pruritic eruption on her trunk after swimming at a beach in Florida. Of note, the lesions are limited to skin that was covered by her bathing suit. The most likely diagnosis is:

A. Swimmer’s itch

B. Cutaneous larva migrans

C. Cercarial dermatitis

D. Seabather’s eruption Correct Choice

E. Swimming pool granuloma

Seabather’s eruption characteristically involves areas covered by swimwear, as a result of coelenterate larvae becoming trapped underneath bathing suits. The causative organisms are larval forms of Edwardsiella lineata (sea anemone) and Linuche unquiculata (thimble jellyfish).

108) The Jarisch-Herxeimer reaction is most closely associated with the release of which of the following cytokines?

35

A. IFN-alpha

B. IL-10

C. IL-12

D. IL-4

E. TNF-alpha Correct Choice

TNF-alpha. The Jarisch-Herxheimer reaction is associated with increased plasma concentrations of TNF-alpha after antibiotic treatment of syphilis. The Jarisch-Herxheimer reaction has also been described following treatment of louse-borne relapsing fever, lyme disease and leptospirosis

109) The causative organism of epidemic typhus is:

A. Salmonella typhi

B. R. prowazekiiCorrect Choice

C. Francisella tularensis

D. R. typhi

E. R. akari

Epidemic typhus is caused by infection with R. prowazekii

110) The expanding annular erythematous patch shown developed in a 25 year-old woman after returning from a weekend at her summer home in Long Island, New York. The vector of this infection is:

A. Lutzomyia verrucarum

B. Ixodes dammini Correct Choice

C. Ixodes ricinus

D. Ctenocephalides felis

E. Pediculus humanus corporis

This is an example of erythema migrans, seen in Lyme disease. Ixodes dammini is the principal vector in the northeastern U.S

111) Streptobacillus moniliformis is the causative organism of which infectious disease?

A. Glanders

36

B. Rat-bite fever (Haverhill fever)Correct Choice

C. Tularemia

D. Cat scratch disease

E. Scrub typhus

Rat-bite fever (Haverhill fever) is caused by Streptobacillus moniliformis

112) Which antibiotic is best to treat this condition caused by Bartonella hensalae.

A. Ceftriaxone

B. ErythromycinCorrect Choice

C. Clindamycin

D. Fluconazole

E. Trimethoprim/sulfamethoxasole

Bartonella hensalae is the causative agent of bacillary angiomatosis. The differential diagnosis of bacillary angiomatosis may include pyogenic granulomas and Kaposi's sarcoma. The treatment of choice is erythromycin

113) The treatment of choice of the tropical infectious disease shown is:

A. Ivermectin

B. Mebendazole

C. Permethrin

D. Pentavalent antimony Correct Choice

E. Diethylcarbamazine

The ulcerated nodule shown here is characteristic of cutaneous leishmaniasis (CL). Leishmaniasis is treated with pentavalent antimony

114) Tick-borne Relapsing Fever is caused by:

A. B. duttoniiCorrect Choice

B. B. henselae

C. B. burgdorferi

37

D. B. recurrentis

E. B. bacilliformis

Relapsing Fever can be either Louse-borne or Tick-borne. Tick-borne Relapsing Fever is caused by B. duttonii, while Louse-borne Relapsing Fever is caused by B. recurrentis

115) Cat scratch disease is caused by infection with:

A. Bartonella speciesCorrect Choice

B. Gram-positive bacilli

C. Spirochetes

D. Rickettsiae

E. Gram-positive cocci

Cat scratch disease is caused by infection with B. henselae - a gram-negative bacillus of the genus Bartonella

116) Corynebacterium minuttissimum is responsible for which of the following infections?

A. Erysipeloid

B. Trichomycosis axillarisCorrect Choice

C. Majocchi's granuloma

D. Erysipelas

E. Malakoplakia

Corynebacterium minutissimum is responsible for causing trichomycosis axillaris, a superficial bacterial overgrowth of axillary hairs characterized by circumferential yellow (most common), red, or black granular concretions. Majocchi's granuloma is a dermatophyte infection. Erysipelas is caused by beta-hemolytic group A streptococcus. Malakoplakia is usually caused by S. aureus, P. aeruginosa, or E. coli. Erysipeloid is caused by Erysipelothrix rhusiopathiae. Corynebacterium is also the causative organism in erythrasma and pitted keratolysis

117) Measles is caused by which type of virus?

A. ParamyxovirusCorrect Choice

B. Togavirus

C. Parvovirus

D. Picornavirus

38

E. Rhabdovirus

Measles is caused by an RNA virus known as paramyxovirus. The illness is characterized by high fever, cough, coryza, conjunctivitis, and Koplik's spots. Viral exanthem characterized by erythematous macules and papules beginning on the face and spreading caudally 3-4 days after prodromal symptoms

118) A 27 year-old woman who is 30 weeks pregnant presents with erythema migrans. The treatment of choice for this patient is:

A. Doxycycline

B. AmoxicillinCorrect Choice

C. Erythromycin

D. Clindamycin

E. Chloramphenicol

In the setting of pregnancy, amoxicillin is the treatment of choice for Lyme Disease since doxycycline is contraindicated

119) The treatment of choice for Loiasis is:

A. Diethylcarbamazine (DEC)Correct Choice

B. Permethrin

C. Ivermectin

D. Malathion

E. Chloramphenicol

The recommended treatment for loiasis is Diethylcarbamazine (DEC

120) The most likely target for exfoliative toxin A in bullous impetigo is:

A. Desmoglein 1Correct Choice

B. BPAG2

C. BPAG1

D. Desmocollin

E. Desmoglein 3

39

Bullous impetigo is caused primarily by staphylococcus aureus phage type 71. This bacteria produces exfoliative toxin A binds to desmoglein 1 and produces produces the blisters characteristic of bullous impetigo

121) The infectious disease shown is most likely caused by which of the following organisms?

A. L. mexicana complex

B. L. infantum

C. L. major

D. Klebsiella pneumoniae rhinoscleromatis Correct Choice

E. L. donovani

The figure is an example of rhinoscleroma, which is caused by Klebsiella pneumoniae rhinoscleromatis. While the diagnosis of mucocutaneous leishmaniasis (MCL) could be considered, none of the leismania species listed as possible responses are causes of MCL

122) A 8 year-old girl presents to the pediatrician with a poorly marginated blue-red single indurated plaque on her right cheek. What is the most likely causative organism?

A. Klebsiella pneumoniae

B. Staphyloccus aureus

C. Beta-hemolytic group A streptococcus

D. Haemophilus influenzaeCorrect Choice

E. Pseudomonas aeruginosa

The most likely diagnosis is H. flu cellulitis. This infection usually occurs in children and is characterized by a single indurated plaque with poorly delineated margins. Erysipelas, an infection caused by beta-hemolytic streptococcus group A, usually presents with well delineated margins in adult patients

123) A 35 year-old woman who works in the animal product industry presents with a painless hemorrhagic bulla. A diagnosis of anthrax is suspected. Gram stain of the vesicle fluid should reveal which of the following?

A. Gram-negative cocci

B. Guarnieri bodies

C. Gram-positive bacilli Correct Choice

D. Gram-negative bacilli

40

E. Gram-positive cocci

Anthrax is caused by Bacillus anthracis, which is a gram-positive spore-forming rod

124) The mechanism of action of this virulence factor of Bacillus anthracis is via increasing the activity of tumor necrosis factor alpha:

A. Lethal toxinCorrect Choice

B. All of the above answers are correct

C. Edema toxin

D. Polyglutamate acid capsule

E. None of the above answers are correct

Bacillus anthracis is responsible for causing Anthrax. Anthrax of the skin is characterized by a painless edematous nodule which rapidly degenerates into an eschar. B. anthracis has 3 virulence factors: a polyglutamate acid capsule which inhibits phagocytosis of the bacteria, edema toxin (edema factor and protective factor) which results in edema secondary to induction of cAMP pathway, and lethal toxin (lethal factor and protective factor) which leads to shock and death via increasing TNFalpha activity

125) At what rate of speed does this parasite migrate through the skin?

A. 0.1 cm/day

B. 10 cm/day

C. 1 cm/day

D. 2 cm/dayCorrect Choice

E. 100 cm/day

The infection depicted is larva migrans or creeping eruption which is caused by Ancylostoma braziliense. This nematode is typically a hookworm of cats and dogs. It migrates at a rate of 2 cm/day. Larva currens migrates at a rate of 10 cm/day

126) High doses of which of the following antiviral agents has been associated with thrombotic thrombocytopenic purpura in immunosuppressed patients?

A. Acyclovir

B. ValcyclovirCorrect Choice

C. Cidofovir

D. Foscarnet

41

E. Famciclovir

Thrombotic thrombocytopenic purpura has been reported with high doses of valcyclovir in immunosuppressed patients

127) Orf virus infection is also known as:

A. Ecthyma

B. Pseudocowpox

C. Ecthyma contagiosumCorrect Choice

D. Milker's nodule

E. Echtyma gangrenosum

Orf virus infection is also known as Ecthyma contagiosum. Ecthyma Gangrenosum is caused by Pseudomonas aeruginosa. Ecthyma is caused by Staphylococcal or streptococcal pyoderma. Pseudocowpox and Milker's nodule are also known as paravaccinia and caused by udders of infected cows

128) Botryomycosis is:

A. An acute, disseminated infection involving the genitourinary system

B. A fungal infection caused by T. tonsurans

C. A bacterial infection commonly associated with Staphylococcus aureusCorrect Choice

D. A bacterial infection commonly associated with Clostridium botulinum

E. A fungal infection caused by M. canis

Botryomycosis is an uncommon, chronic, idonlent disorder characterized by nodular, crusted, purulent lesions. Sinuses that discharge sulfur granules are present. These heal with atrophic scars. The granules yield most commonly Staphylococcus aureus on culture, although cases caused by Pseudomonas aeruginosa, E. coli, Proteus, Bacteroides, and Streptococcus have been reported

129) Xenopsylla cheopis is the vector responsible for which infectious disease?

A. Human Granulocytic Ehrlichiosis

B. Scrub typhus

C. Endemic typhusCorrect Choice

D. Human Monocytic Ehrlichiosis

E. Epidemic typhus

42

Xenopsylla cheopis (rat flea) is the vector of endemic typhus, which is caused by R. typhi

130) Erythema infectiosum is caused by a:

A. None of these answers are correct

B. Single stranded DNA virusCorrect Choice

C. Double stranded DNA virus

D. RNA virus

E. Herpes virus

Erythema infectiosum is caused by parvovirus B19 which is a single stranded DNA virus

131) Which of the following vectors is responsible for transmitting Chagas’ disease?

A. Reduviid bug Correct Choice

B. Sandfly

C. Black fly

D. Tstse fly

E. Mosquito

The reduviid big is the vector of American trypanosomiasis (Chagas disease). The vector of African trypanosomiasis is the tstse fly

132) All of the following statements are true of Bacillus anthracis infection except:

A. inhalation, GI and cutaneous forms exist

B. ciprofloxacin and doxycycline are first line treatments

C. Spores remain stable for decades

D. 20% mortality rate in untreated cutaneous infectionsCorrect Choice

E. no recommendations from CDC exist on anthrax vaccine

Anthrax can present in three different clinical forms: cutaneous, inhalational, and gastrointestinal. The cutaneous form appears as a painless vesicle that later forms an eschar (malignant pustule). The cutaneous form has a mortality rate of less than 1% if treated an up to 20% if untreated

133) Which of the following is the vector responsible for the transmission of Verruga Peruana?

43

A. Ctenocephalides felis

B. Tsetse fly

C. Lutzomyia verrucarumCorrect Choice

D. Pediculus humanus corporis

E. Simulium slossonae

Verruga Peruana is caused by infection with B. bacilliformis, which is transmitted by the sandfly, Lutzomyia verrucarum

44