Exogenous protein as the cause of nephrotic-range proteinuria.

Hematuria and proteinuria developed in a young woman with waxing and waning symptoms suggestive of systemic lupus erythematosus. Quantitatively, the proteinuria was in the nephrotic range, but other manifestations of the nephrotic syndrome were absent. Serologic evaluation demonstrated normal results. The hematuria was subsequently found to be self-induced and related to foreign objects in the bladder. Urine protein electrophoresis confirmed severe proteinuria with a spike in the gamma region. Immunoelectrophoresis demonstrated that the proteinuria was not of human origin. Subsequent urinary protein values were normal. This case exhibits features compatible with Münchausen's syndrome and shows that severe proteinuria may be factitious.