Browsing by Author "Uzal, Francisco A."

Gas gangrene occurs in several animal species, and it is caused by one or more clostridial species. In horses, the disease is most often caused by Clostidium perfringens type A. Although Clostridium sordellii has been associated with gas gangrene in ruminants and humans, cases of the disease associated with this microorganism have not been described in horses. We report 8 cases of gas gangrene by C. sordellii in horses. These cases were characterized by myonecrosis and cellulitis, associated with systemic changes suggestive of toxic shock. The diagnosis was confirmed by gross and microscopic changes combined with anaerobic culture, fluorescent antibody test, immunohistochemistry and/or PCR. The predisposing factor in these cases was an injection or a traumatic skin injury. C. sordellii should be considered as a possible etiologic agent in cases of gas gangrene in horses.

Enterotoxemia caused by Clostridium perfringens type D is an important disease of sheep and goats with a worldwide distribution. Cerebral microangiopathy is considered pathognomonic for ovine enterotoxemia and is seen in most cases of the disorder in this species. These lesions are, however, rare and poorly described in goats. In this paper, we describe the vasculocentric brain lesions observed in 44 cases of caprine spontaneous C. perfringens type D enterotoxemia. Only one goat had gross changes in the brain, which consisted of mild cerebellar coning. However, 8/44 (18%) of the cases showed microscopic brain lesions, characterized mainly by intramural vascular proteinaceous edema, a novel and diagnostically significant finding. The precise location of the edema was better observed with PAS and Gomori’s stains. The areas of the brain most frequently affected were cerebral cortex, corpus striatum (basal ganglia) and cerebellar peduncles and both arterioles and venules were involved. Most of the goats of this study showed lesions in the intestinal tract (enteritis, colitis and typhlitis), although pulmonary congestion and edema, hydrothorax, hydropericardium and ascites were also described. This is the largest study to date of neuropathological changes in naturally-occurring cases of caprine type D enterotoxemia, and it describes the main features of the cerebral microangiopathy in this species. Although the intramural edema found, for the first time, in these caprine cases is useful for the diagnosis of enterotoxemia when observed, its absence cannot exclude the disease because, in goats, it is only present in a small number of cases.