[Medication of the month. Febuxostat (Adenuric)]. / Le médicament du mois. Fébuxostat (Adenuric).

Gout is a rheumatologic disease due to the deposition of urate (the catabolite of purines) crystals within joints. Prevalence of the disease is high. Potential articular and nephrological complications are numerous. Therefore, a chronic, preventive and effective therapy is required in specific patients. Dietary changes are frequently insufficient and urate-lowering therapy is thus necessary, like uricosuric or xanthine oxydase inhibitors. The objective of these therapies is to lower serum urate levels below 6 mg/dL. The xanthine oxydase inhibitor allopurinol is still the most used in the context of gout prevention. However, allopurinol tolerance and efficacy are far from optimal. Now, a new therapy is available in Belgium, the febuxostat. Febuxostat is a new xanthine oxidase inhibitor.Tolerance and therapeutic effect seem better compared to allopurinol. In this article, we review pharmacological data about this new treatment. We also review the most important clinical trials underlining strengths and limitations of febuxostat.

[Detection and estimation of chronic kidney disease]. / Détection et estimation du niveau de la maladie rénale chronique.

The prevalence of chronic kidney disease is increasing. An early and precise diagnosis of renal insufficiency requires a measurement of the glomerular filtration rate. Formulas based on serum creatinine to determine the glomerular filtration rate have brought, compared to serum creatinine alone, an improvement in this precision. However, in many clinical conditions, they may give incorrect information. Using 24 h urine collection, calculation of creatinine clearance can be more adequate and accurate in conditions where patient's anthropometric characteristics are far from the normal range. However, this 24 h urine collection is often variable and its validity could be criticized. When a very precise determination of glomerular filtration rate is needed, a method of reference is required such as that using chrome EDTA or iohexol. Each nephrological exploration also needs a urine analysis for detection of proteinuria. When a positive urine dipstick test is noted, a quantification of proteinuria must be done either after 24 h urine collection or more easily by determining the proteinuria/creatininuria ratio on an urine sample.