Probable new syndrome in a Mexican family with congenital palmar polyonychia and postaxial limb defects

Abstract

Congenital palmar polyonychia (CPP) is a rare and usually sporadic birth defect. We report on a Mexican girl with CPP of both 5th fingers and her sister with ectrodactyly with ulnar ray deficits and agenesis of the ulna. In previous reports, CPP has been seen in ectrodactyly with involvement of the ulna and ulnar digital rays and with postaxial polydactyly. Such findings observed in our patients can be considered a form of CPP. Autosomal dominant inheritance of CPP is more likely based in previous informative families with vertical transmission and instances of male-to-male transmission. The present and two previous families with affected sibs only may represent parental gonadal mosaicism, whereas de novo mutation or incomplete evaluation of relatives could be an explanation for sporadic cases. Variable expression of the CPP phenotype may be a new autosomal dominant entity, i.e., a CPP-postaxial limb defect syndrome.

Congenital palmar polyonychia with postaxial limb defects may be the same as the ulnar–mammary syndrome

“…Duplication of the nail on the ventral (volar) surface of the 5th digit was described by Bamshad et al [1996] in 5 of 33 members from a large UMS pedigree. Figures 3 and 4 in that paper illustrate ectopic positioning of the nail of the 5th digit and absence of the interphalangeal creases, as seen in Patient 1 reported by Román Corona‐Rivera et al [2004]. Similar dorsalization of the ventral surface of the 5th digit with duplication of the nail‐bed is shown in Figure 1B in a further paper by the same group [Bamshad et al, 1999].…”

“…I read, with interest, the article by Román Corona‐Rivera et al [2004], describing a female infant with 5th finger congenital palmar polyonychia (CPP) and her sister with bilateral ulnar agenesis and postaxial oligodactyly. Although the authors may be correct in suggesting that these features constitute a novel CPP‐postaxial limb defect disorder, they do not discuss the phenotypic overlap with the ulnar–mammary syndrome (UMS).…”

Reply to letter to the editor by Crow: “Probable new syndrome in a Mexican family with congenital palmar polyonychia and postaxial limb defects”

“…We appreciate the comments of Dr. Crow regarding the article in which we described a probable new syndrome in a Mexican family with congenital palmar polyonychia (CPP) and postaxial limb defects (PLD) [Corona‐Rivera et al, 2004]. We agree with his recommendation that ulnar‐mammary syndrome (UMS) needs to be considered on the differential diagnosis of patients with CPP‐PLD syndrome.…”