Glomerulocystic kidney disease in a family.

BACKGROUND

Glomerulocystic kidney disease (GCKD) is a rare renal disorder, the identity of which has long 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 11 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 11 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 11 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 1 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.