Typhoid Fever

Dept. Infectious Disease

2nd Affiliated Hospital

CMU

Definition

Typhoid fever is an acute infectious disease of di

gestive tract caused by typhoid bacillus.

Place of lesson lymphatics in the terminal ileum

Pathological feature proliferation of large m

ononuclear cells derived from MPS

Definition Clinical feature sustained fever relative slow pulse toxic symptoms a rose-color rash splenomegaly and hepatomegaly leukopenia Complication hemorrhage & perforation

Etiology Causative organism: Typhoid bacillus

genus salmonella group D

Pathogenicity: endotoxin

Resistance: Stable in environment, sensitive to hea

t, acid, common disinfectants

Etiology Antigenicity:

O antigen: lipopolysaccharide group-special H antigen: protein, strain-special Vi antigen: polysaccharide

Epidemiology Source of infection Patient, Carrier, shed bacteria in feces Route of transmission Fecal-oral route:

contaminated food or water contagious spread spread by insect

Susceptibility Epidemic features sporadic cases high incidence in fall & summer

Pathogenesis Bacillus Stomach killed by gastric acid incubation Small intestine penetrate mucosa period Regional lymphatics Blood stream - first bacteremia initial MPS in liver, spleen, bone marrow Blood stream -second bacteremia endotoxin liver spleen regional lymphotics Clinical symptoms absces inflammation

Pathology Proliferation of large mononuclear cell

1st week 2nd 3rd week 4th week proliferation necrosis heal edema ulceration no scar

Clinical manifestationIncubation period: 7-23 day(average 10 to

14 days)

Typical typhoid fever: Initial period Fastigium Defervescence Convalescence

Clinical manifestation Initial period

onset: insidious, gradual fever: T stepwise fashion rising non-special symptoms:

Clinical manifestation Fastigium

sustained fever toxic symptoms:

NS apathy, tinnitus, delirium,lethargy, coma DS anorexia, abdominal Pain, diarrhea Constipation CS relative slow pulse, bradycardia, myocarditis

Clinical manifestation Fastigium

rose-colored rash: erythematous macules or papules occur on 6~13 days upper abdomen

hepatomegaly and splenomegaly

Clinical manifestation Devervescence Convalescence

Clinical manifestation Clinical type:

Mild type common type prolonged type, ambulatory type fulminate type

Clinical manifestation Relapse: It occur 1~3week after T has reached

normal. The illness follows a similar pattern to the primary attach. Blood culture positive.

Recurrence: It occur 3~4 after the illness. T begin to fall, then rise again. Blood culture positive.

Complications Intestinal hemorrhage Intestinal perforation Toxic hepatitis and myocarditis Pneumonia

Laboratory Findings Blood picture: leukopenia Bacteria culture:

blood bone morrow urine and stool

Laboratory Findings Widal test: agglutination of serum reaction 5 Ag: “O” “H”, “HABC”

titer:O>=1:80 H>=1:160 results analysis:

Diagnosis Epidemiological data Clinical manifestation Laboratory findings Definitive diagnosis: bacteria culture

positive

Differential Diagnosis Typhus rickettsises malaria disseminated TB

Treatment General therapy Etiologic therapy

guinolone: first choice cephalosporins: 2nd and 3rd generation chloromycetin

Prevention Control of source of infection: isolation Interruption of route of

transmission Protection of susceptible

population : Vaccinated with vaccine

Paratyphoid Paratyphoid A & B are the same as typhoid

fever Paratyphoid C: septics or gastro-interitis