Renal insufficiency is a component of COACH syndrome

Abstract

Two sisters, ages 23 years and 6 years, respectively, were found to have congenital ataxia, bilateral coloboma, mental retardation and abnormal liver function. Magnetic resonance imaging showed cerebellar vermis hypoplasia in the younger girl and liver biopsy showed hepatic fibrosis in the older sister. This combination of findings suggested a diagnosis of COACH syndrome which is characterized by hypoplasia of cerebellar vermis, oligophrenia, congenital ataxia, coloboma, and hepatic fibrosis. COACH syndrome is a newly recognized condition. So far, five cases have been reported from three sibships. We report two additional cases from one sibship and suggest that several other cases may already exist in literature that were not recognized as having COACH syndrome. The occurrence of multiple cases in single sibships suggests autosomal recessive inheritance. In addition to previously described findings typical of COACH syndrome, the older of our patients showed progressive renal insufficiency with fibrocystic changes on renal biopsy. Renal function has not been described consistently in previous reports of COACH syndrome but has been abnormal in all cases in which it has been investigated. We suggest that renal insufficiency should be considered a common manifestation of COACH syndrome. © 1996 Wiley‐Liss, Inc.

Joubert-like syndrome unlinked to known candidate loci

“…[11][12][13][14][15] An association of CVH with both chorioretinal coloboma and renal disease has also been reported in 15 patients including four sib pairs. 7, [16][17][18][19][20][21] The renal abnormalities in these cases were variably described as medullary cystic renal disease, as mild autosomal recessive polycystic kidney disease, as nephronophthisis, and as interstitial fibrosis. In these patients, abnormal eye movements and mental retardation were also recorded.…”

Lack of large, homozygous deletions of the nephronophthisis 1 region in Joubert syndrome type B

“…It is still possible that heterozygote (non-deletion) mutations in the NPH1 gene may be contributed by one parent, while an extended de novo deletion might be present on the other chromosome, giving rise to extrarenal symptoms by a dominant mechanism. However, such deletions would have to have occurred de novo in the patients, since all parents were without symptoms in the [22], oculo-renal-cerebellar syndrome [23], COACH syndrome [24,25], or Arima syndrome [26]. Keuth et al [3] have recently reviewed the presence of vermis aplasia in JSB.…”

Retinal Abnormalities Characteristic of Inherited Renal Disease

“…Although they have medullary renal cysts, they do not necessarily develop renal failure. Optic nerve coloboma, 44,41 mental retardation, nystagmus, and congenital ataxia occur.…”