A novel hypokalaemic polymyopathy and subsequent unrelated nutritional thiamine deficiency in a young Burmese cat

An 8-month-old female spayed Burmese cat was referred for investigation of reduced appetite, reluctance to walk and jump and amaurosis. On serum biochemistry there was severe hypokalaemia and marked elevation of creatine kinase, suggestive of hypokalaemic polymyopathy. The neurological signs were consistent with thiamine deficiency. The cat was negative for the periodic hypokalaemic polymyopathy (PHP) of Burmese cats, and was ultimately diagnosed with a previously undescribed potassium wasting nephropathy requiring ongoing oral potassium supplementation. The response to treatment was excellent and the cat has remained clinically normal over a 12-month follow-up period.

PHP in Burmese cats has been well described, but all cases to date have been shown to be secondary to a genetic mutation in WNK4, resulting in potassium wasting into the urine. This is the first case report of another potassium wasting nephropathy in a young Burmese cat, with subsequent development of nutritional thiamine deficiency.