Metaplasia of the parietal layer of Bowman’s capsule in a cat

Abstract

A 5-year-old male cat presented at the clinic with status epilepticus following long-term sodium valproate treatment. On clinical examination, the cat lost consciousness and had frequent seizures. The animal’s condition did not improve by intravenous administration of diazepam. Serum biochemical abnormalities included marked uremia and hyperphospatemia. A provisional diagnosis of chronic kidney disease was made based on laboratory data. Further investigation and treatment was declined by the owner, and the cat was euthanized. Necropsy was performed, and on histopathological examination, numerous lesions were observed within some of the glomeruli. Specifically, metaplasia of the parietal cells was noted, with a change from short cuboidal to tall columnar cells within Bowman’s capsule. These cells were composed of round to oval vesicular nuclei with prominent nucleoli. The underlying basement membrane was thickened, and there was evidence of pre-glomerular fibrosis.