[The thin membrane syndrome. A cause of asymptomatic microscopic hematuria]

The use of urinary diagnostic strips with high sensitivity for hemoglobin has revealed microscopic hematuria in individuals with no symptoms or signs of illness. The thin membrane syndrome may be a frequent cause of such asymptomatic hematuria, and this diagnosis is particularly topical in the case of glomerular hematuria, i.e. with a dysmorphic erythrocyte picture on urinary microscopy. The thin membrane syndrome represents a new entity with an uncertain prognosis. The distinction between thin membrane syndrome and Alport's disease is important but difficult. Modern immunochemical investigations may be helpful in this regard. Until more information is available concerning the thin membrane syndrome, regular control of blood pressure, serum creatinine, urinary sediment and urinary protein is recommended in these patients.