Piogranulomatous peritonitis by Nocardia concava in dog - Case Report

Nocardiosis is caused by an aerobic, gram-positive, ramificated and filamentous bacteria of the Nocardia genus, subgroup Actinomycetos. The diagnosis is based on the presence of the inflammatory lesions with the morphologically compatible microorganism associated with microbiological and molecular isolation and identification. The objective of this work is to report a case of nocardiosis in a canine that developed peritoneal pyogranulomatous inflammation six months after ovariosalpingohisterectomy. The animal had hyperthermia, abdominal distention, tachypnea, polydipsia, hyporexia, hypocorous mucosae and pasty feces. The laboratory findings revealed mild anemia and leukocytosis due to neutrophilia with left deviation and hypoalbuminemia. A mass in the mesogastric region and peritoneal effusion were evidenced by abdominal ultrasonography. The fluid was classified as pyogranulomatous exudate and the animal underwent exploratory laparotomy for abdominal lavage and mass removal. Despite the therapeutic procedures and clinical alterations the dog died. Piogranulomatous peritonitis was the main anatomopathological alteration which was associated with Nocardia spp. Molecularly, the isolated species approaches the N. concava species through phylogenetic analysis. This specie was described as a cause of infection in humans in Asia; however, there are no records in literature on the canine species, being this the first report.