Renal tubular dysgenesis: A not not uncommon autosomal recessive syndrome: A review

Abstract

Renal tubular dysgenesis is a recently recognized autosomal recessive condition characterized by short and poorly developed proximal convoluted tubules, leading to oligohydramnios, Potter sequence, and neonatal respiratory failure. We report an additional 9 cases from one pediatric center, suggesting that this syndrome is not as rare as was previously thought. Normal amniotic fluid volumes in affected pregnancies prior to the 22nd week of gestation have been documented, compromising early prenatal diagnosis. Late second trimester sonographic demonstration of oligohydramnios, with structurally normal kidneys, should suggest this diagnosis and the need for detailed post-mortem pathological examination.

The prepattern transcription factor Irx3 directs nephron segment identity

“…Importantly, the segments do not operate independently but rely on the correct spatial organization along the nephron to insure normal excretory functions. Absence of specific tubular segments, such as the proximal convoluted tubules, has been observed in man and usually causes stillbirth or neonatal lethality (Allanson et al 1992). In recent years, major insights into transcription factors and signaling pathways that control the early stages of nephrogenesis have been gained (Vainio and Lin 2002;Dressler 2006).…”

Fibroepithelial bladder polyp and renal tubular dysgenesis: an unusual cause of third‐trimester oligohydramnios.

“…3 Renal tubular dysgenesis is often a sporadic finding but has also been reported as an autosomal recessive disorder. 4,5 This condition has been described in both male and female offspring and is associated with abnormalities of the cranium, wide sutures, and abnormal fontanelles in 25% of cases. 5 Pathologically, RTD is characterized by kidneys that are usually of normal size but may be slightly enlarged.…”

“…4,5 This condition has been described in both male and female offspring and is associated with abnormalities of the cranium, wide sutures, and abnormal fontanelles in 25% of cases. 5 Pathologically, RTD is characterized by kidneys that are usually of normal size but may be slightly enlarged. Microscopically, there is an absence or incomplete differentiation of the proximal convoluted tubules.…”

“…These histopathologic changes are not normal for any stage in renal development. 5 The etiology of this abnormality in nephrogenesis is uncertain, but 2 hypotheses have been proposed. One hypothesis for this condition is depletion of fetal growth factors, specifically transferrin or other tubular maturation factors.…”

“…6 The second is vascular compromise and chronic renal hypoperfusion. 5 Genest and Lage, 4 in a series of 500 perinatal autopsies, reported 6 cases in which the kidneys lacked normalappearing renal tubules. One live-born infant died in the perinatal period and had RTD.…”