Pathology of leptospirosis and acute fatal foreign body macroaspiration in a one-year-old Nigerian indigenous breed of dog

Macroaspiration is a common cause of mortality in dogs. Majority of cases of acute macroaspiration in dogs that leads to death are iatrogenic. In this case, we present report of leptospirosis in a bitch that died of macroaspiration. A carcass of a one-year-old Nigerian indigenous breed of dog was presented to the University of Jos Veterinary Teaching Hospital, Polo, for postmortem examination. Rhipicephalus sanguineus was recovered from the skin. The carcass was moderately dehydrated, emaciated and the mucous membranes were yellowish. The colon was severely haemorrhagic with blood-stained fluid in the abdominal cavity. The entire liver parenchyma was markedly jaundiced. The trachea contained froth mixed with fine black granular substance (activated charcoal). The spleen was markedly enlarged (splenomegaly). The bladder contained yellowish urine with a urine specific gravity of 1.010, marked bilirubinuria, glucosuria, proteinuria and mild haematuria. Microscopic examination of the urine revealed fine granular casts, transitional epithelial cells, leucocytes and red blood cells. Histopathological examination of tissues showed centrilobular hepatic necrosis, necrosis and desquamation of tubular epithelial cells, glomerular degeneration and complete destruction of the Bowman’s capsule, moderate lymphocyte depletion, marked infiltration of mononuclear cells into the mucosa and submucosa. It was concluded that even though the dog had leptospirosis, the immediate cause of death was foreign body macroaspiration.