NEPHROTOXIC EFFECTS OF FUMARIC-ACID THERA PY OF PSORIASIS

The treatment of psoriasis using fumaric esters is efficient, as shown by long-term, uncontrolled observations [3, 7] as well as in randomiz ed, double-blind, placebo-controlled studies [2, 10, 11, 12]. The effi cacy probably is due to an immunosuppressive effect on T-lymphocytes a nd cytokines. Unwanted effects have been observed as flush, nausea and diarrhea as well as hematologic and renal alterations. The present, p rospective study analyses possible renal side effects systematically. 42/47 patients were observed more than 3 to 70 months (mean 16,5 mo) w ithout changing their renal retention parameters. However, 21/42 patie nts revealed altered urinary proteins: a micromolecular tubular protei nuria developed from a physiological status in 12/21, from a pre-exist ing pathological status in 8/21 patients. A macromolecular glomerular proteinuria has been found in only 1/21 patients after therapy, but tr ansiently in further 4 out of the 12/21 patients with initial tubular damage. In all but 2/21 patients alterations disappeared within 6 mont hs. A high daily and cumulative dose of fumaric esters was associated with tubular damage. The transient tubular resorption defect in 21/42 patients was not accompanied by reduction of the glomerular filtration rate. However, by additional tubular hazards (infections, toxic hypov olemia drugs etc.) an acute kidney failure might occur. The analysis o f a tubular parameter (SDS-PAGE, alpha(1)- or beta(2)-microglobulin) d uring treatment is recommended.