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.

Objectives The objective of this study was to determine the prevalence of Toxoplasma gondii IgM and IgG positive cats in Los Angeles County, California. T gondii antibodies are common in sera from cats in most reported studies around the world. Although the majority of infected cats never develop clinical disease, development of acute infection and recrudescence of latent infection secondary to immunosuppression has been reported. Knowledge of the serologic status of T gondii may be important when considering immunosuppressive treatments.

Methods T gondii IgM and IgG antibody titers were measured in 225 cats. Sera from owned cats tested at a multispecialty veterinary hospital were included both retrospectively and prospectively (n = 125). Sera from feral cats tested through a collaborating humane society were included prospectively (n = 100).

Results Of the 13 (5.8%) cats with IgM titers, 10 were positive at the minimal cut-off titer (1:64), one cat was clinically ill and none were currently positive for IgG antibodies, suggesting false-positive results for nine cats, giving an adjusted IgM prevalence rate of 1.8% (95% CI 0.7–4.5). A total of five (2.2%) cats were positive for IgG antibodies and no cat was positive for both antibodies.

Conclusions and relevance Most studies of T gondii antibodies in cat sera from California have shown higher prevalence rates, suggesting the cats in this municipality have a low risk of exposure. The study emphasizes that serological test results do not necessarily correlate to the presence of clinical illness.

Case summary A domestic shorthair cat presented to the Animal Referral Hospital (Brisbane, Australia) after having the left pelvic limb incorrectly amputated. The cat was unable to ambulate on the remaining right pelvic limb due to a chronically subluxated stifle. A stifle arthrodesis was performed on the right pelvic limb to manage the injury. Follow-up radiographs performed 5 months postoperatively demonstrated stifle arthrodesis with no detectable complications. The owner reported that aside from some difficulties in toileting, the cat had a good quality of life and was capable of performing the majority of daily activities. Stifle arthrodesis in a feline pelvic limb amputee appears to be a viable treatment option. After a period of rehabilitation and adaptation, the cat in the case report has been able to lead a near-normal lifestyle.

Relevance and novel information To the authors’ knowledge, this is the first report of the outcome and complications associated with stifle arthrodesis in a feline pelvic limb amputee. This is also the first report of stifle arthrodesis in a cat using the bilateral plating technique.

Case summary The patient was a castrated male American Shorthair cat, approximately 14 years old, weighing 3.4 kg. The patient had chronic kidney disease (CKD) (International Renal Interest Society stages 3–4) as an underlying disease. The cat was examined at a hospital for intermittent lethargy and seizures. Hypoglycaemia was repeatedly observed, and the insulin level was 1.78 ng/ml (reference interval 0.27–0.69) when the blood glucose was 49 mg/dl. Although the cat was tentatively diagnosed with insulinoma, surgery was not recommended because of the severe CKD. Although frequent feeding and prednisolone treatment were initially attempted, blood glucose decreased to 24–42 mg/dl. Diazoxide was additionally prescribed at a dose of 5.2 mg/kg q12h. The cat’s clinical signs improved, and the blood glucose was in the range of 75–103 mg/dl during the first 2 months. It was maintained at >50 mg/dl until the patient died of renal failure 161 days after the start of diazoxide treatment. With regard to adverse events, vomiting once every 2–3 days without weight loss and non-regenerative anaemia were observed, which might have been at least partially caused by diazoxide treatment. An insulinoma was definitively diagnosed via pathological autopsy.

Relevance and novel information This is the first reported case of long-term treatment with diazoxide in a cat with insulinoma. Since it was effective in situations where conventional therapies were unsuccessful, diazoxide could be useful as a new therapeutic option for cats with insulinoma. Since adverse events, such as progression of vomiting frequency and non-regenerative anaemia, were observed, careful monitoring was required during administration.

Case summary A 10-year-old male castrated domestic shorthair cat was presented for evaluation of a 3-day history of increased inspiratory effort. The cat had received prednisolone 1 mg/kg PO q24h for 1 year due to chronic diarrhea. On physical examination, the patient exhibited severe stridor, intermittent open-mouth breathing and bilateral mucopurulent nasal discharge. Subcutaneous emphysema was palpated over the dorsal cervical region. Mild hypoventilation (PvCO₂ 55.1 mmHg; approximate reference interval 35–45 mmHg) was identified. Cervicothoracic radiographs showed marked gas tracking within cervical soft tissues with concurrent laryngeal thickening, pulmonary nodules, a bronchial pulmonary pattern, pneumomediastinum and aerophagia. The cat was hospitalized and treated overnight with oxygen and intravenous fluid therapy before anesthesia the next day. On laryngoscopy, a large tracheal mass was observed arising from the right subglottic region and was removed using biopsy forceps. CT revealed an additional mass at the level of the tracheal bifurcation causing marked luminal narrowing of the trachea and proximal main bronchi. The cat made a good initial recovery, although moderate stridor persisted. Five days later, the cat was re-examined due to recurrence of respiratory distress and orthopnea, and the owner elected euthanasia. Histopathology revealed severe nodular obstructive eosinophilic plasmacytic laryngotracheitis with intranuclear inclusion bodies positive for feline herpesvirus-1 on immunohistochemistry.

Relevance and novel information This report describes the presentation and management of a cat with respiratory distress secondary to intratracheal eosinophilic masses caused by feline herpesvirus-1. Although the outcome was ultimately unsatisfactory, to the authors’ knowledge, this clinical presentation has not been previously reported.

Case series summary Cystic bronchiectasis was diagnosed in three cats with known histories of chronic coughing using CT and histopathology. CT of the lungs revealed large space-occupying lesions that compressed and displaced unaffected pulmonary parenchyma and vessels. The masses were soft tissue attenuating in two cases and gas-cavitated with areas of dependent fluid in one case. All three cats were found to have mineral attenuating material in lesions and in other dilatated airways. Generalized bronchial wall thickening was also present and indicative of chronic lower airway disease. These findings were supported by histopathology showing inflammatory changes and dilatated airways in the collected tissues. In the two cases in which post-contrast CT series were acquired, the lesions had rim-enhancement.

Relevance and novel information Cystic bronchiectasis is a rare presentation of bronchiectasis in cats and may mimic a pulmonary mass lesion, which could be mistaken for neoplasia or abscessation. The lack of central enhancement or presence of gas cavitation on CT, concurrent presence of diffuse bronchial wall thickening, other areas of bronchiectasis and the presence of broncholithiasis may alert the clinician to the possibility of cystic bronchiectasis related to chronic lower airway disease.

Case summary This report describes the case of a 7-year-old male neutered domestic mixed-breed cat that was initially referred to the Veterinary Hospital of the State University of Londrina for evaluation of a 2-week history of abdominal distension and a 2-day history of anorexia, infected with feline immunodeficiency virus (FIV). Abdominal ultrasound revealed an expansive mass located around the pancreas and right hepatic lobe. In the transoperative macroscopic observation, multiple white nodules were visualized in the liver, pancreas, mesentery, intestine, stomach and peritoneal wall. Immunohistochemical examination revealed that neoplastic cells demonstrated a strong positivity for AE1/AE3 and CK20. A sparse immunoreactivity to chromogranin A was observed, which demonstrates neuroendocrine cell labeling. The histopathologic changes associated with the immunohistochemical profile confirmed the diagnosis of metastatic carcinoma with neuroendocrine differentiation, originating from the pancreas.

Relevance and novel information Neuroendocrine tumors of the pancreas are rare and are associated with a poor prognosis in humans. In humans, approximately 7% of neuroendocrine tumors develop in the pancreas, and the 5-year survival rate for a pancreatic neuroendocrine tumor is 53%, according to the American Cancer Society. To our knowledge, only one case has been described in the feline species so far. Due to the rarity of this type of tumor in cats, there is little information about predisposition related to age, sex or breed, as well as the main clinical signs presented, survival time and treatment options.

Case series summary A 1-year-old castrated male domestic shorthair cat was suspected with myasthenia gravis (MG) based on neurological examination, complete blood count (CBC), serum biochemistry, radiography and electrophysiological examination. In addition, a 9-year-old spayed female domestic shorthair cat was diagnosed with MG based on neurological examination, CBC, serum biochemistry, radiography, ultrasonography and increased acetylcholine receptor antibody titre. Positioning head tilt (PHT) was observed at the time of diagnosis in both cats.

Relevance and novel information Although the pathophysiology of PHT in cats is not fully understood, the mechanism for PHT in cats with MG may be similar to that of cats with hypokalaemic myopathy, supporting our hypothesis that muscle spindle dysfunction causes PHT.