Metformin-associated lactic acidosis: reinforcing learning points.

Metformin-associated lactic acidosis (MALA) carries a high mortality rate. It is seen in patients with type 2 diabetes on metformin or patients who attempt suicide with metformin overdose. We present the case of a man in his early 20s with type 2 diabetes, hypertension and hypothyroidism who presented with agitation, abdominal pain and vomiting after ingesting 50-60 g of metformin; he developed severe lactic acidosis (blood pH 6.93, bicarbonate 7.8 mEq/L, lactate 28.0 mEq/L). He was managed with intravenous 8.4% bicarbonate infusion and continuous venovenous haemodiafiltration. He also developed acute renal failure (ARF) requiring intermittent haemodialysis and continuous haemodiafiltration. MALA is uncommon and causes changes in different vital organs and even death. The primary goals of therapy are restoration of acid-base status and removal of metformin. Early renal replacement therapy for ARF can result in rapid reversal of the acidosis and good recovery, even with levels of lactate normally considered to be incompatible with survival.

Randomized, controlled, single-blind study on use of autologous keratinocytes on a transfer dressing to treat nonhealing diabetic ulcers.

AIM: To compare the rate of healing of diabetic neuropathic ulcers using cultured autologous keratinocytes delivered on chemically defined transfer discs (Myskin) (active treatment) versus healing obtained with cell-free discs (placebo). MATERIALS AND METHODS: After a 4-week lead-in period patients (randomly assigned) received active or placebo treatments weekly for 6 weeks. All patients then received active treatments for a maximum of 12 treatments where required. Altogether, 16 patients with a total of 21 ulcers resistant to conventional therapy were recruited from four specialist diabetic centers in three cities. RESULTS: All 21 ulcers were treated and of these ten healed and eight improved, with two failing to respond (one ulcer was lost due to autoamputation). For analysis according to the study criteria, however, only the 12 patients with 12 index ulcers who completed treatment protocols were eligible - five in the placebo group and seven in the active group. Of these, five ulcers healed completely and seven were reduced by more than 50%. Complete healing took a median of ten active applications. CONCLUSIONS: Repeated regular applications of the patient's keratinocytes, delivered on the carrier dressing, initiated wound healing in ulcers resistant to conventional therapy, with 18 out of 21 ulcers responding. The healing observed did not appear attributable to patient recruitment or the cell-free carrier dressing but to the delivery of the cultured cells.