LEPTOSPIROSIS DEFINITION 1 Leptospirosis is a kind of

LEPTOSPIROSIS

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

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

ETIOLOGY z 1. pathogen : pathogenic leptospira z 2. features of leptospia: helicoid with hook, length 6~ 20 um, G darkfield microscope; in korthof’s media;

z ETIOLOGY z several months z in water and moist soil (PH 7. 0~7. 5) z 3. Classification: z 23 serogroups z z and more then 200 serotypes in the world; 19 serogroup and 74 serotypes in china. icterohemorrhagic group, pomona group

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

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

z. EPIDEMIOLOGY z 4. Epidemiologic features: z (1)season: summer and fall; z (2) nosogenic age: z young and middle age, children z (3)occupation: z farmer, slaughter, z fisher, veterinarian.

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

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

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

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

PATHOLOGY z 1. basic pathological change is z infective, toxic injured of systemic z capillaries; z 2. severe: lung, liver, kidneys, brain. z exudation, hemorrhage, z edema or necrosis. z

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

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

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

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

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

z. CLINICAL MANIFESTATIONS z 3. Icterohemorrhagic type: (Weil , s disease) âhemorrhage: petechiae, ecchymoses, hemoptysis, hematemesis etc. ârenal injury: proteinuria, RBC, WBC, cast, oliguria, azotemia, uremia.

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

z. CLINICAL MANIFESTATIONS â CSF is abnormal. § pressure increase § pleocytosis<500 × 106/L § protein is normal or elevated slightly. § glucose and chloride is normal. § leptospira isolation: positive.

CLINICAL MANIFESTATIONS z. SEQUELAE z 1. after fever : 1~5 days after defervascence z 2. sequelae of eyes: 1 week~1 month z iridocycyclitis, choroiditis , uveitis z 3. reactive meningitis z 4. cerebroarteritis obliterans: 2 w~2 m

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

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

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

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

TREATMENT z 1. Pathogenic therapy z 1). first choice: penicillin z 40万 u q 6 h or q 8 h im 7 days z note: Herxheimer reaction first time - small amount 5万 u âim â z 2). Gentamycin 8万 u q 8 h im

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

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