Correspondence (reply): In Reply

We thank Prof. Kiesewetter for mentioning losartan. When treating hypertension in patients with hyperuricemia, the uricosuric effect of different preparations should be deployed in a useful way. The relative risk of developing gout differs substantially between the various classes of antihypertensive substances. The relative risk of developing gout for calcium channel blockers is 0.87, for losartan, the risk is 0.81. For all other classes of substances it is >1 (relative risk [RR] for ACE inhibitors, 1.24; for betablockers, 1.48; for all angiotensin receptor blockers except losartan, 1.29; for diuretics, 2.36) (1).

The ACP guidelines were published after our article had been submitted. As Dr. Tsamaloukas mentioned, they follow the principle of symptom orientation, whereas the rheumatological guidelines seek to achieve target values. From the authors‘ perspective, the current evidence for a target serum concentration of uric acid (especially <5 mg/dl) is too weak to strive for this. However, further studies on the risks and benefits of uric acid are needed. The authors agree especially with regard to the neuroprotective effect of uric acid, as described in the article. Allopurinol is usually well-tolerated. About 2% of patients taking it develop mild erythema. However, those taking allopurinol may develop the life-threatening hypersensitivity syndrome, whose estimated incidence is 0.1%. Some studies have described an association between that syndrome and renal failure, diuretic intake, recently started treatment with allopurinol, a higher initial dosage, and the presence of HLA B*58:01 (2). Genotyping all patients with a prescription for allopurinol seems unjustifiable to us in terms of health economics, but one might start thinking about it in the context of the criteria mentioned earlier.

With regard to Prof. Kiesewetter‘s suggestion I would like to briefly focus on the effect of alkalinizing urine in the setting of treatment for hyperuricemia. Because of the weak or lacking evidence, it is not recommended for the treatment of hyperuricemia. The cited literature also points out the weak evidence. In treating urolithiasis, however, it is included among the therapeutic options (3). A Mediterranean diet, as recommended in the article, is consistent with the cited dietetic recommendations (4, 5). A diet that is low in protein and rich in vitamins is recommended in this setting.