Glomerulocystic kidney disease in a family

Background. Glomerulocystic kidney disease (GCKD) is a rare renal disorder, the identity of which has Ion g been discussed. GCKD can occur in a familial form with autosomal dominant transmission. The presence of GCKD in families affected with autosomal dominant polycystic kidney disease (ADPKD) has lent support to the hypothesis that GCKD may be an early manifestation of ADPKD. In families with hypoplastic forms of GCKD, the HNF-1beta gene has recently been identified. Methods. Three members of a family were evaluated: a girl (case 1) and her brother (case 2), who were aged I I and 12 years, respectively, at the beginning of the study, and, subsequently, the girl's son, when he was 4 years old (case 3). They all had mild renal insufficiency. Clinical, morphological and genetic evaluations were performed on I I members of the family. Results. Case 1. A mild reduction in renal length with modest dysmorphology of renal calyces and hyperechogenic parenchyma were present when the patient was I I years old. At the age of 29 some small renal cysts were identified, which remained unchanged over the next 8 years. Renal dysfunction remained stable. Case 2. A slight reduction in size of a hyperechogenic kidney was found. Cysts were seen at the age of 38. Renal dysfunction remained unchanged. Case 3. Kidneys were of normal size. Small cysts were found at the age of 9 years. In cases I and 2, histopathology was highly consistent with GCKD. In none of the cases associated pathological conditions could be identified. Haplotype reconstruction allowed the exclusion of PKD1 and PKD2 genes. No mutation of the HNF-1beta gene was found. Conclusions. The morphological data from the three cases are suggestive of GCKD. The involvement of PKD1, PKD2 and HNF-1beta gene mutations was excluded.