Nephronophthisis is an autosomal recessive condition which invariably progresses to end-stage renal failure (ESRF). Three variants are recognised:
juvenile NPH1
infantile NPH2
adolescent NPH3
Juvenile nephronophthisis is the most frequent genetic cause of ESRF in children and young adults. The incidence ranges from 1 in 50,000 to 1 in 1,000,000. The higher incidences are seen in Europe while the disease is are in the USA.
Symptoms: Polyuria, polydypsia, decreased urinary concentrating ability and secondary enuresis. Presents between 4 and 6 years of age. Anaemia and growth retardation occur later and are usually pronounced. Median age of ESRF is 13 years.
Extra-renal problems may also be seen. These include eye abnormalities (Senior-Loken syndrome) and skeletal abnormalities.