Benzbromarone therapy in management of refractory gout

Aim. To assess the efficacy and safety of benzbromarone in patients with renal impairment and severe tophaceous gout (despite receiving optimal conventional therapy). Methods. Six patients with refractory gout (despite optimal therapy) were treated with benzbromarone. Uric acid levels and number of gout attacks were recorded monthly. Adverse events to medications were also recorded. Results. After 1 year of treatment with benzbromarone, average uric acid level reduced from 0.61 mmol/L to 0.46 mmol/L. Repeated measures tests on the changes in uric acid were clinically significant (p=0.01). The frequency of acute attacks of gout was reduced from 16 (8–20) to 7.3 (1–16); p=0.01. None of the patients reported adverse events with the medications. There were no acute flares resulting from initiation of medications. Conclusion. Benzbromarone is effective in lowering uric acid levels and in reducing the number of acute attacks of gout in patients who have failed optimal treatment. Making this drug more readily available will increase our therapeutic choices for urate reduction and help decrease the morbidity associated with gout. Gout is a common metabolic condition that is on the increase worldwide. It affects at least 1% of men in Western countries, with a male to female ratio ranging from 7:1 to 9:1. 1 Gout is the commonest form of arthritis in men over the age of 40 in New Zealand. Epidemiological survey conducted in 1996 showed gout to be more common in Maori (6.4%) than Europeans (2.9%). 2 The prevalence of gout in Maori men has risen from 4.5–10.4% previously to 13.9%; and in European men, from 0.7–2.0% previously to 5.8%. 2–4 Proposed principal contributory factors leading to the increased prevalence of gout include increased longevity, increased prevalence of hypertension, obesity, diabetes mellitus, renal failure, and cardiac failure. There is also an increased use of diuretic and low-dose aspirin use. Changing dietary trends and alcoholism may also have contributed to the increased prevalence. 5 Management of gout remains unsatisfactory in a significant proportion of patients in New Zealand. 6 It is difficult to identify the reasons for this but this could be in part due to the complex interactions of diseases seen in these patients in combination with lack of therapeutic choices. The goal of antihyperuricemic treatment is the reduction uric acid below 0.42mmol/L. In cases of tophaceous gout, levels less than 0.25mmmol/L may be required for resolution of tophi. Optimal therapy entails combination of a purine-restricted diet and pharmacological agents in conjunction with patient education with regards to management of acute and prophylactic therapies.