Pancreatitis associated with Mycoplasma felis infection in a cat

Case summary A 7-year-old domestic shorthair cat was presented for periuria, apathy, fever, inappetence, diarrhoea and vomiting. A complete blood count and biochemistry analysis revealed severe thrombocytopenia, severe azotaemia, moderate panhypoproteinemia, mildly elevated DGGR lipase activity and mildly elevated liver enzyme activity. Abdominal ultrasound showed a hypoechoic pancreas with surrounding hyperechoic fat demonstrating dirty shadowing and ascites (protein-poor transudate). The cat was treated medically for pancreatitis with fluid therapy, antiemetics and pain medication. During the hospitalisation period, the cat developed severe anaemia and received multiple whole blood transfusions yet showed no signs of clinical improvement. A repeat ultrasound examination performed after 8 days showed progressive pancreatic lesions and ongoing ascites. Analysis of the free abdominal fluid revealed neutrophilic inflammation despite low protein and cell concentration, with the presence of numerous very small, coccoid, basophilic inclusions within neutrophils, raising the concern for a septic peritonitis due to Mycoplasma species. Quantitative PCR (qPCR) confirmed the presence of Mycoplasma felis. After 10 days of hospitalisation, the cat developed refractory septic shock and was euthanased. Necropsy revealed severe necrotising pancreatitis with systemic changes consistent with sepsis and microthrombi. qPCR testing for M felis in pancreatic tissue also yielded a positive result. Relevance and novel information Although pancreatitis is a common disease in cats, this case report presents the first documented occurrence of M felis as the suspected primary pathogen causing pancreatitis in a cat.