[Progressive renal insufficiency in a 55-year-old man with psoriasis].

Treatment with tumor necrosis factor alpha (TNF-α) inhibitors is a well-established therapeutic strategy for various autoimmune diseases. However, little is known about renal complications and possible causality of renal injury due to this treatment. The following case of a patient with psoriasis demonstrates the difficulties in classifying renal complications of anti-TNF-α therapy versus kidney involvement caused by the underlying disease.