Gross hematuria in minimal-change disease nephrotic syndrome

Abstract

Sirs, Idiopathic minimal-change nephrotic syndrome (NS) remains one of the commonest causes of NS in childhood, especially in the non-black population [1]. While transient microscopic hematuria has been described in 10–30% of children with minimal-change NS [2, 3], gross hematuria has not. In fact, gross hematuria in any child with idiopathic NS is exceedingly rare [4]. I recently took care of a child with new onset of NS, who at initial presentation, had gross hematuria. This Caucasian boy was admitted to the hospital at 9 months of age with anasarca, serum creatinine of 0.3 mg/dL, low serum albumin of 1.2 g/dL, elevated total cholesterol of 446 mg/dL and massive proteinuria (urine protein-to-creatinine ratio of 12.8); his coagulation studies and a renal ultrasound with doppler were normal. He was noted on admission to have pinkto red-colored urine that persisted throughout his 1-week hospital stay. The urine had a specific gravity of 1.005, a pH of 7.0 and 50–100 red blood cells per high-power field. Although the patient’s young age and hematuria were recognized to be atypical for idiopathic NS, since all his serologies were negative/normal (antinuclear antibody, complement C3 and C4, hepatitis B and C), it was elected to treat him empirically with oral steroids, without a renal biopsy. The patient was steroid responsive, although it took 1 month for his urine protein to become negative and for his serum albumin to normalize. Microscopic hematuria, which had persisted until then, also resolved. Since his initial presentation, he has had multiple relapses, all of which have been steroid responsive. The patient’s course was complicated by the development of bullous pemphigoid 1 year after the onset of NS. At that time, even though his renal disease was in remission, a renal biopsy was performed at the request of the dermatologist to rule out an immune complex-mediated disease. The renal biopsy demonstrated minimal-change disease with no immune complex deposits on immunofluorescence or on electron microscopy. His glomerular basement membranes were of normal thickness. This is the first report, to my knowledge, of a child with minimal-change NS presenting with gross hematuria. The purpose of this report is to add gross hematuria to the list of unusual manifestations in children with minimalchange NS and to re-emphasize that even in children with NS who some have atypical features, consideration should be given to administering a trial of empiric steroids before renal biopsy is performed. It is important to recognize, though, that our patient certainly did not fit the classic demographic profile for minimal-change NS in that he had infantile NS, and also since he eventually developed a rare skin disease, and therefore may not be representative of most children with idiopathic minimal-change NS.