[Megacaliosis--diagnosis and differential diagnosis (author's transl)].

Megacaliosis is a renal dysplasia which is characterised by rudimentary papillae. The pathogenesis, clinical features and radiological appearances in fire cases are described and the differential diagnosis from other types of calyceal ectasia is discussed, In typical cases the diagnosis of megacaliosis can be made from the excretion urogram. We regard divided renal function studies as essential before making the diagnosis. Where the renal changes are not quite typical, it is necessary to exclude obstructive and inflammatory disease, vesico-ureteric reflux and renal tuberculosis.