Periodic hypokalaemic polymyopathy in Burmese and closely related cats: a review including the latest genetic data.

GLOBAL IMPORTANCE: Hypokalaemic polymyopathy is a genetic disease of Burmese cats that has been encountered in Australasia, Europe and South Africa. CLINICAL FEATURES: Affected cats usually present with signs of muscle weakness and muscle pain in the first year of life. Although certain clinical features, such as ventroflexion of the head and neck, are especially characteristic, some cats do not display these signs. Usually weakness is periodic or episodic, but occasionally it is incessant. DIAGNOSTIC CHALLENGES: In the past, diagnosis was problematic in that clinical signs and a lowered serum potassium concentration were not always observed synchronously. This necessitated serial serum potassium concentration determinations, testing of serum creatine kinase activity and exclusion of other potential causes of muscle disease in cats (including muscular dystrophies, Toxoplasma myositis, immune-mediated polymyositis, organophosphorus intoxication and envenomations). Signs in affected cats often waxed and waned, possibly in response to changes in dietary factors and stress, and some cats could apparently 'grow out of' the condition. RECENT ADVANCES AND FUTURE PROSPECTS: Recent molecular genetics research has identified a single nonsense mutation in the gene (WNK4) coding for lysine-deficient 4 protein kinase, an enzyme present primarily in the distal nephron. The underlying pathomechanism in affected cats is therefore likely to be a potassium wasting nephropathy, as this enzyme is involved in complex sodium/potassium exchange mechanisms in the kidney. Additional functional characterisation of the condition is warranted to define precisely how, why and when the serum potassium concentration declines. The diagnosis of Burmese hypokalaemia is now straightforward, as an inexpensive PCR test can identify affected homozygous individuals, as well as carriers. The elimination of this condition from the Burmese breed, and also from pedigree cats infused with Burmese lines, such as the Bombay, Tonkinese and Tiffanie breeds, should therefore be possible.

Intramuscular glargine with or without concurrent subcutaneous administration for treatment of feline diabetic ketoacidosis.

OBJECTIVE: To describe treatment response and outcome in 15 cats with diabetic ketoacidosis (DKA) initially stabilized with glargine administered intramuscularly (IM) with or without subcutaneous (SC) glargine. MATERIALS AND METHODS: Fifteen cats diagnosed with DKA were initially administered IM glargine (1-2 U) and in most cats (12/15 cats) this was combined with SC glargine (1-3 U). This was followed by intermittent IM glargine as required at intervals of 2 or more hours (range 2-22 h) and SC glargine (1-2 U) every 12 hours. KEY FINDINGS: All 15 cats survived and were discharged from hospital (median 4 d; range 2-5 d) and one-third (5/15) of cats subsequently achieved remission (median time 20 d; range 15-29 d). Complications included hypokalemia and hypophosphatemia, which were likely the result of DKA therapy rather than glargine treatment specifically. SIGNIFICANCE: This study demonstrates that glargine administered IM is an effective treatment for DKA in cats, and may provide an alternative to regular insulin. The same vial used for initial treatment of DKA can then be used for subsequent management with SC glargine injections. Future prospective randomized controlled trials evaluating clinical outcomes in cats with DKA using different types and routes of administration of insulin are warranted. A prospective randomized controlled trial is required to compare outcomes for IM and IV administration of glargine and regular insulin in DKA cats with or without SC glargine.

Long-term safety, efficacy and palatability of oral meloxicam at 0.01-0.03 mg/kg for treatment of osteoarthritic pain in cats.

Osteoarthritis is a chronic, painful condition that is now recognised as affecting a large proportion of cats. Non-steroidal anti-inflammatory drugs (NSAIDs) have proven efficacy in dogs and humans but there are limited published data on the use of NSAIDs in the long-term management of this condition in cats. This prospective study aimed to assess the long-term safety and palatability of oral meloxicam and its efficacy in treating osteoarthritic pain in cats when given at a dose of 0.01-0.03 mg/kg once daily. Forty cats diagnosed with osteoarthritis completed the trial with a mean treatment duration of 5.8 months. Gastrointestinal upset in 2/46 (4%) cats was the only adverse effect noted. No deleterious effect on renal function was detected in cats studied. Owners subjectively assessed treatment efficacy as good or excellent in 34/40 (85%) of cases. The results of this study showed oral meloxicam to be safe and palatable long-term treatment for osteoarthritis in cats when given with food at a dose of 0.01-0.03 mg/kg.