LEPTOSPIROSISNo2 hospital CMU departmentof infectious diseaseHuang Fen

DEFINITION 1. Leptospirosis is a kind of zoonoticinfectious disease caused by pathogenic leptospires; 2. rats and swine are cardinal source of infection; 3. the disease often occurs in summer and fall;

DEFINITION 4. clinical features: three symptoms, three signs, internal organ damage, seguelae of eyes and nerve system 5. treatment: penicillin.

ETIOLOGY

1.pathogen : pathogenic leptospira2.features of leptospia: helicoid with hook, length 6~ 20 um,G - darkfield microscope; in korthofs media;

ETIOLOGY several months in water and moist soil (PH7.0~7.5)3.Classification: 23 serogroups and more then 200 serotypes in the world; 19 serogroup and 74 serotypes in china. icterohemorrhagic group, pomona group

1.Source of infection: rat: apodemus agrarius, rice field type; pigs: flood or rain type; patientEPIDEMIOLOGY

EPIDEMIOLOGY

2.Routes of transmission: (1) water borne (indirect contact transmission): by skin,mucosa,when skin is injured. (2) direct contact transmission: (3) food borne3.Susceptibility of population:

EPIDEMIOLOGY4.Epidemiologic features: (1)season: summer and fall; (2) nosogenic age: young and middle age,children (3)occupation: farmer,slaughter, fisher,veterinarian.

EPIDEMIOLOGY

4.Epidemiologic features: (4)epidemic type : rice field type flood type rain type

PATHOGENESIS leptospira skin,mucosaInitial stage leptospiremia toxic symptoms (1~3days) three symptoms: fever,myalgia,fatigue; three signs: conjunctival suffussion; muscle tenderness; enlargement of lymphonodes;

PATHOGENESIS severe toxic symptoms lesion of organs: influenza form pneumorrhagic formmiddle stage icterohemorrhagic form(3~10d) meningoencephalitis renal failure form.

PATHOGENESIS

immunopathological reaction after fever; sequelae of eyes; reactive meningitis; cerebro arteritis obliterans. convalescent stage

PATHOLOGY1. basic pathological change is infective,toxic injured of systemic capillaries; 2. severe:lung,liver,kidneys,brain. exudation,hemorrhage, edema or necrosis.

CLINICAL MANIFESTATIONS Incubation period: 2~28 days usually 7~13days;1. Influenza-typhoid type:5~10days three symptoms: fever,myalgia and fatigue. three signs: conjunctival suffusion,

CLINICAL MANIFESTATIONS three signs: conjunctival suffusion, tenderness of gastrocnemius muscle; enlargement and tenderness of superficial lymphnodes. Inguinal and axillary lymphodes.

CLINICAL MANIFESTATIONS 2. pneumorrhagia form: 1). three symptoms and three signs 2). pneumorrhagia symptoms(3~4d) (1). mild pneumorrhagia typecough,expectoration with blood.a few moist rales.X-ray of chest: scattering spotty and small fasciola shadow

dyspnea,palpitaton,aspharyxia,rales.

CLINICAL MANIFESTATIONS 2. pneumorrhagia form: (2) diffuse pneumorrhagia type short breathing, palpitation, dysphoria, massive hemoptysis, asphyxia, cyanosis, a lot of moist rales.X-ray: extensive fasciola shadow

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CLINICAL MANIFESTATIONS

3.Icterohemorrhagic type:(Weil ,s disease) 1). three symptoms and three signs 2). jaundice, hemorrage, renal injury (4~5d) liver injury: anorexia,vomiting, jaundice, abnormal liver function.

CLINICAL MANIFESTATIONS

3.Icterohemorrhagic type:(Weil ,s disease) hemorrhage: petechiae,ecchymoses,hemoptysis,hematemesis etc.renal injury: proteinuria, RBC, WBC, cast, oliguria,azotemia,uremia.

CLINICAL MANIFESTATIONS

4.renal failure type: oliguria, azoteinia, uremia.5.meningoencephalitis type: 1). three symptoms and three signs 2). 3~4days later, meningitis, encephalitis. headache,vomiting,meningeal irritation, lethargy,coma,paralysis or convulsion.

CLINICAL MANIFESTATIONS

CSF is abnormal. pressure increase pleocytosis

SEQUELAE 1. after fever :1~5days after defervascence2. sequelae of eyes: 1week~1month iridocycyclitis, choroiditis , uveitis3.reactive meningitis4.cerebroarteritis obliterans:2w~2m hemiplegia aphasiaCLINICAL MANIFESTATIONS

LABORATORY FINDINGS:1. routine examination: 1). blood routine examination: WBC is increased slightly; 2).urine routine examination: protein (2/3) 2. serological examination: 1).microscopic agglutination test (MAT) detect antibody >1:400

LABORATORY FINDINGS: 2). ELISA: serum and CSF IgM antibody 3. pathogenic test 1).blood culture: 2).PCR: DNA

DIAGNOSIS1.epidemiologic data: 1).epidemic area;2).epidemic season;3).a history of contact with contaminated water;2.clinical manifestations:3.Lab findings:

DIFFERENTIAL DIAGNOSIS 1.Influenza; Typhoid fever, 2.Lobar pneumonia; 3.Viral hepatitis; 4.Viral meningitis; 5.Epidemic hemorrhagic fever;

TREATMENT1.Pathogenic therapy 1). first choice: penicillin 40 u q6h or q8h im 7days note: Herxheimer reaction first time - small amount 5 u im 2). Gentamycin 8 u q8h im

TREATMENT 2.Symptomatic therapy 1). Herxheimer reaction physical cooling, sedative, hydrocortisone. 2). pneumorrhagia type sedative, hydrocortisone, cardiotonics 3.treatment of sequlea

PREVENTION1.control of pigs: 1). stable breeding 2).immunized by vaccine2.killing of rats,3.cutting route of transmission,4.vaccination: multivalent vaccine

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