Inherited renal tubular dysgenesis may not be universally fatal.
Inherited renal tubular dysgenesis (RTD) is caused by mutations in the genes encoding components of the renin-angiotensin cascade: angiotensinogen, renin, angiotensin-converting enzyme (ACE), and angiotensin ΙΙ receptor type 1. It is characterized by oligohydramnios, prematurity, hypotension, hypocalvaria, and neonatal renal failure. The histological hallmark is the absence or poor development of renal proximal tubules. Except for a few cases, the prognosis has been thought to be universally poor, with patients dying either in utero or shortly after birth. We report a 3-year-old infant diagnosed clinically with RTD. The infant survived the neonatal period after 2 weeks of anuria subsequently subsiding. Hypotension and hyperkalemia normalized eventually with administration of fludrocortisone. A revision of renal tissue obtained from a sibling that died shortly after birth revealed normal glomeruli and distal tubules but no identifiable proximal tubules. A novel mutation in the ACE gene was found in the surviving child, who remains with stage 4 chronic kidney disease and normal neurodevelopment. As the number of surviving cases of RTD increases, it should be emphasized to the parents and the neonatal care team that it may not be universally fatal as previously reported. A trial of fludrocortisone may correct hyperkalemia and hypotension.
Schreiber
Ruth
R
Department of Pediatrics, Soroka University Medical Center, Ben Gurion University of the Negev, Beer Sheva, Israel. ruthsc2@clalit.org.il
Gubler
Marie-Claire
MC
Gribouval
Olivier
O
Shalev
Hanna
H
Landau
Daniel
D
D001002:Anuria / Q000235:genetics; D002675:Child, Preschool; D005260:Female; D005438:Fludrocortisone / Q000627:therapeutic use; D020022:Genetic Predisposition to Disease; D040941:Heredity; D006801:Humans; D006947:Hyperkalemia / Q000188:drug therapy / Q000235:genetics; D007022:Hypotension / Q000188:drug therapy / Q000235:genetics; D007687:Kidney Tubules, Proximal / Q000002:abnormalities / Q000201:enzymology; D008297:Male; D009154:Mutation; D016104:Oligohydramnios / Q000235:genetics; D007703:Peptidyl-Dipeptidase A / Q000235:genetics*; D010530:Peritoneal Dialysis; D010641:Phenotype; D011247:Pregnancy; D016896:Treatment Outcome; D014564:Urogenital Abnormalities / Q000201:enzymology / Q000235:genetics / Q000628:therapy
D007703:Peptidyl-Dipeptidase A; D005438:Fludrocortisone