Nephrogenic Diabetes Insipidus, Type II (AQP2)
Nephrogenic diabetes insipidus, type II is a pan-ethnic, autosomal recessive disease caused by pathogenic variants in the gene AQP2. Onset is in the first month of life. The disease is characterized by the inability of the kidneys to concentrate the urine. Therefore, too much water is lost in the urine and patients can easily develop dehydration. Patients urinate excessively and consequently require more water than usual. Without treatment, patients can develop bladder complications; brain damage from repeated episodes of dehydration can also occur. Patients may have poor feeding, gastrointestinal problems, and short stature. With early diagnosis and proper treatment, life expectancy is normal. No genotype-phenotype correlations have been reported.
For information about carrier frequency and residual risk, please see the residual risk table.