Bladder function impairment in aquaporin-2 defective nephrogenic diabetes insipidus.

Abstract

BACKGROUND:

The aim of this study was to describe the urological complications associated with nephrogenic diabetes insipidus (NDI) due to a mutation in aquaporin-2 (AQP2), a collecting-duct protein activated by ADH signalling.

METHODS:

We provide a case series description of a group of seven patients with autosomal recessive NDI due to AQP2 gene mutation, receiving routine medical management since diagnosis in the first months of life.

RESULTS:

Mean urine osmolarity at diagnosis and last follow-up was 89+/-25 and 83+/-18 mosm/l, respectively. Hydroureteronephrosis was observed in all children, beginning at age 3 years. Two children have daytime enuresis at ages 7 and 10 years and all children older than 6 years continue to have nocturnal enuresis. Markedly enlarged bladders were observed as early as age 4 years in all patients. Trabeculated bladder walls were found in three children. Urodynamic studies performed in two daytime incontinent children revealed a hypotonic-large-capacity type of neurogenic bladder. No impairment in kidney function is currently observed.

CONCLUSIONS:

The severe renal concentrating defect in this type of NDI is associated with the development of hydroureteronephrosis followed by bladder enlargement and dysfunction. Careful follow-up is needed in order to assure that no bladder outlet obstruction and/or renal insufficiency develop.

• Authors: Hanna Shalev, Igor Romanovsky, Nine V Knoers, Salomon Lupa, Daniel Landau
• Journal: Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association (Nephrol Dial Transplant) Vol. 19 Issue 3 Pg. 608-13 (Mar 2004) ISSN: 0931-0509 [Print] England
• PMID: 14767016 (Publication Type: Journal Article)

Chemical References

• AQP2 protein, human
• Aquaporin 2
• Aquaporins

Topics

• Adolescent
• Adult
• Aquaporin 2
• Aquaporins (genetics)
• Arabs (genetics)
• Child
• Child, Preschool
• Diabetes Insipidus, Nephrogenic (genetics, physiopathology)
• Female
• Humans
• Infant
• Male
• Mutation
• Pedigree
• Radiography
• Retrospective Studies
• Ultrasonography
• Urinary Bladder (diagnostic imaging, physiopathology)