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BACILARY
DYSENTRY
a. Definition ~Acute infectious disease of intestine caused by dysentery bacilli(genus shigella) ~» Place of lesion: sigmoid & rectum ~ Pathological feature: diffuse fibrious exudative inflammation a. Etiology ~ Causative organism: dysentery bacilli, genus shigella, gram-stained negative, non-motile short rod, ~Groups: 4 serogroups &47 serotypes a. Etiology *S. dysenteriae: the most severe *=S. flexneri: the epidemic group and easily turn to chronic *S. boydii: tropical and subon *S. sonnei: the most mild °— Epidemiology pidemiology ~Source of infection: patients and carriers ~Route of transmission: fecal-oral route ~Suceptibility of population: immunity after infection is short and unsteady, no cross-immune a. — Epidemiology » Epidemic features: *season: summer & fall *Flexneri, Soneii, dysentery *age: younger children common Bacteria = intestine + penetrate mucus normal intestinal flora ! sig A multiply in epithelia prevent attaching cell & Proper lamina inflammation endotoxin vessel contraction endogenous pyrogen —~ fever superficial mucosal necrosis and ulcer | diarrhea mixed with blood & pus, abdominal pain a. — _ Pathogenesis-toxic strong - allergy to endotoxin | demethyl-adrenaline ) DIC i * micro-circulatory failure shock, cerebral edema cerebral hernia Ea. : aa Pathology hyperemia, edema, leukocyte infiltration, superficial necrosis, ulcer. *chronic: edema, polypoid hyperplasia, *toxic: colon: hyperemia, edema, micro- capillary was invaded — Clinical manifestation ~Incubation period: 1-2 day, (hours to 7 days) ~Acute dysentery common type *mild type *toxic type Ea. — Clinical manifestation > mild type: ( atypical type) *caused by S. sonnei “low fever or no fever *abdominal pain is mild *stool mixed with mucus, without blood & pus «diagnosis by isolation of bacteria ae ar ie | a — Clinical manifestation > toxic type: *age: 2 to 7 yrs. *abrupt onset, high fever, T 40°C * dysphoria, lethargy, convulsion repeatedly,coma. *circulatory & respiratory collapse “diarrhea mild or absent at beginning a. — Clinical manifestation ~ chronic dysentery: > 2 months *chronic delayed type:chronic obscure type “acute attack type a — Clinical manifestation > chronic delayed type: long-time and repeated abdominal pain, diarrhea, stool mixed with mucus, blood & pus. with fatigue, anemia, malnutrition. 
