[Xanthogranulomatous pyelonephritis in early childhood]

We report on a two-year-old infant boy in whom a tumorous enlargement of the left kidney which was not imaged in the excretion urogram was discovered by renal sonography after the second urinary tract infection. By synopsis of the clinical data and imaging techniques, but especially by the detection of foam cells in the urinary sediment, we were already able to make the diagnosis of a xanthogranulomatous pyelonephritis before the operation. Since diffuse infiltration of the entire organ was present, total nephrectomy was carried out as the therapy of choice. Besides the case report, in particular the difficulties in the diagnosis of this form of pyelonephritis (especially in infancy) are described.