NEPHRONOPHTHISIS IN SENEGAL - THE FIRST 3 CASES

Nephronophtisis is a familial tubulo-interstitial nephropathy with an autosomic recessive mode of transmission. To our knowledge, it has not been yet reported in Black Africa. We report here the case of a 17-ye ar old female from Senegal who presented with renal failure related to a chronic interstitial nephritis characterized by polyuria, hypocalce mia, natriuresis of 23 mmol/l and serum creatinine level of 1070 mu mo l/l. The parents of this patient were first-degree cousins. Among the 6 siblings, 2 other males were found to have a renal disease. Ultrasou nd examination of the kidneys showed medullary cysts in the 2 affected brothers and the renal biopsy in one case showed tubular atrophy, wit h thickening of the basal lamina and an interstitial fibrosis without glomerular involvment. Molecular genetic analysis confirmed the diagno sis of nephronophtisis, with a homozygous deletion of the NPH1 region. In order to recognize this disease early in life, one has to look for it in patients with tubulo-interstitial nephritis, polyuria, childhoo d enuresia especially when it is associated with growth retardation or tetany. This case raises the issue of consanguinity and endogamy whic h are frequently encountered in Africa. It also extends the geographic and ethnic distribution of nephronophtisis, being the first cases rep orted Black Africans.