leptospirosis

Definition Leptospirosis is a bacterial disease related to genus Leptospira which cause septicemia, It is rare in cats but more common in dogs, cattle Leptospirosis is a zoonotic disease (human). NB: In man: it causes Weil’s disease

Uterus in pregnant animal pathogenesis penetration fever Localized in lung liver jaundice kidney brain Uterus in pregnant animal abortion

Septicemia on serous membranes (pleura ) septicemia leads to petechial hemorrhages and edema on serous membranes (pleura ) :may be seen in other organs as myocardium , adrenal glands, pancreas, gallbladder and lung

Pulmonary hemorrhage

A-Canine Leptospirosis: Pathognomonic Lesions: Acute leptospirosis: Liver: Macroscopic Picture : 1-The liver is enlarged and yellow in color. 2-Yellow m.m. due to icterus. 3-Peticheal hemorrhages on the pleura, pericardium and peritoneum.

Icterus

Microscopic Picture: 1- coagulative necrosis in hepatic cells. 2-Dissociation of the hepatic cells (individualization). 3-hemolytic jaundice with dilation of the bile canaliculi with yellow bile pigments. 4-Hemosiderosis are seen in the kupffer cells. .

Organ : Liver. Stain : H&E. Micro : Dissociation and individualization hepatic cells.

B- Bovine leptospirosis Subacute and Chronic leptospirosis: Macroscopic Picture: 1-The kidneys are enlarged & atrophied (chronic). 2-Grayish-white spots throughout the cortex (white spotted kidney) and the capsule is not easily detached. 3-Smooth or pitted surface with hemorrhage at the corticomedullary junction. .

Microscopic Picture: 1-Agggregations of lymphocytes 2-Extenssive coagulative necrosis. 3-Fibrosis and cystic dilation of some renal tubules in chronic stage. 4-Cellular and hyaline casts

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