EXPRESS: Severe acute intra-abdominal clostridial disease in two cats

Case series summary This case series describes two cats who developed intra-abdominal infections attributable to clostridial species. Case 1 describes a 3-year-old Oriental who presented after acutely vomiting and rapidly declined which culminated in septic shock and death within hours of presentation. Imaging and postmortem revealed severe necrotizing inflammation involving the right kidney and septic peritonitis. Histopathology revealed gram-positive bacilli, consistent with a clostridial infection. Case 2, a 6-year-old Siamese presented with acute lethargy, anorexia, and abdominal pain. An enlarged, cavitated ileocaecal lymph node was identified on ultrasound. Cytology demonstrated abundant bacilli, and anaerobic culture and histopathology confirmed Clostridium septicum. The cat showed rapid clinical recovery following surgical excision of the affected lymph node and surrounding tissue. Relevance and novel information These cases highlight the potential for Clostridium species to cause fulminant intra-abdominal disease in previously healthy cats. Case 1 represents an unusual presentation of a septic abdomen due to Clostridium and subsequent acute decline. Whilst Case 2 represents the first reported instance of spontaneous mesenteric lymphadenitis with abscessation due to C septicum in a previously healthy feline. Both cases demonstrate the severity of this bacterium in causing disease, and the importance of early recognition. The findings highlight the aggressive nature of clostridial disease, and the limitations of aerobic culture alone in diagnosis. This report expands the known host range and clinical manifestations of Clostridium species, supporting its inclusion in the differential diagnosis of necrotizing intra-abdominal disease in cats, even in the absence of predisposing factors.