[Therapeutic effect of retinoic acid in lupus nephritis]

Lupus nephritis is a major cause of morbidity and mortality among patients with systemic lupus erythematosus (SLE). In these patients, treatment with immunosuppressive agents can significantly improve the outcome of lupus nephritis. However, these agents have severe adverse reactions and some patients are refractory to those therapies. Retinoids, a group of natural and synthetic derivatives of vitamin A, play important regulatory roles of cellular proliferation, differentiation and apoptosis. They have been used for the treatment of acute promyelocytic leukemia and inflammatory disorders such as psoriasis and acne. It has also been shown that retinoids have therapeutic effects in various animal models of kidney disease, including lupus nephritis. Based on these findings, retinoids are a promising agent for the treatment of lupus nephritis. We studied the clinical effects of retinoid therapy in patients with lupus nephritis. In open clinical trial, 7 patients with active lupus nephritis that was refractory to steroid therapy were studied. In all these patients, retinoid was added to the immunosuppressive therapy and its therapeutic effects were evaluated. As a result, 4 out of 7 patients showed improvement of the clinical symptoms and laboratory findings, including urinary protein and anti-dsDNA antibody levels. No important adverse effects of ATRA therapy were observed in all patients. Thus, retinoids might be indicated in cases of lupus nephritis that are refractory to conventional immunosuppressive therapy.