Tuberculosis of the central nervous system in cattle in Paraíba, Brazil

Abstract

ABSTRACT: This paper describes six cases of tuberculosis in the central nervous system (CNS) of cattle in the state of Paraíba in northeastern Brazil. We reviewed the autopsy reports of 851 bovine necropsies performed from 2003 to 2016. Seventy-three (8.6%) cattle were diagnosed with tuberculosis and six showed lesions in the CNS. Three cases affected cattle up to two-year-old and other three affected adults. Three cattle presented exclusively nervous signs, two had respiratory signs and weight loss and one did not present any clinical signs. At necropsy, five cattle had thickening of the leptomeninges of the cerebellum, pons, obex, spinal cord and cortex, mainly, in the region near the brain basilar Willis´ circle. Another animal, presented a single focal lesion in the cerebellum. Microscopically we observed moderate to severe granulomatous meningitis and encephalitis. Five cattle presented lesions in the lungs and mediastinal lymph nodes and three of them had disseminated lesions in other organs. In all cattle acid-fast bacilli were observed in the lesions and marked positive for immunohistochemistry with polyclonal antibody anti-Mycobacterium tuberculosis. It is concluded that bovine tuberculosis of central nervous system occurs sporadically in Paraíba, in cattle of different ages, most of them with disseminate lesions in other organs. The location of the lesions suggests that the agent invaded the brain by hematogenous route through the circle of Willis.