Pauci-immune crescentic glomerulonephritis in the Down's syndrome.

Kidney disease is a rare complication in patients with the Down's syndrome. However, with increased survival, it appears that a growing number of these patients present with glomerulonephritis. Most cases have been reported as case reports and include lesions such as mesangiocapillary glomerulonephritis with hypo-complementemia, crescentic glomerulonephritis with anti-neutrophil cytoplasmic antibodies (ANCA), amyloidosis and immunotactoid glomerulopathy. We report the observation of a 38-year-old man with the Down's syndrome who presented with severe renal failure, proteinuria and microscopic hematuria evolving over two months. There was no history of congenital heart disease or urinary symptoms. Percutaneous renal biopsy revealed fibrous crescents, rupture of Bowman's capsule and peri-glomerular granuloma; there were no deposits on immunofluorescence study. Thoracic computerized tomography scan showed alveolar congestion. The patient tested negative for ANCA. At the time of reporting, the patient is on regular chronic hemodialysis. Our case illustrates a distinct entity that further expands the spectrum of renal disease known to occur in the Down's syndrome. Early detection of the renal disorders may prevent or slow down the progression.