The Oto‐Palato‐Digital Syndrome: Variable Clinical Expressions

Abstract

The oto-palato-digital (OPD) syndrome is a rare but well-defined disorder characterized by a skeletal dysplasia of the hands and feet, hearing loss, and anomalies of the palate. Since it was first described by Taybi in 1962, a little over 30 cases have been reported in the literature. A more lethal variant of the syndrome was described later by Fitch and was termed OPD type II. Several studies were conducted to determine the exact mode of inheritance of this syndrome, whereas others have focused on the characterization of the skeletal anomalies and their variations. Otologists were interested in determining the etiology of the associated hearing loss. We report 4 cases of patients with the spectrum of anomalies that characterize the OPD syndrome. These patients include 3 siblings and 1 unrelated patient who presented to our service complaining of hearing loss. The skeletal anomalies, special features, and audiologic findings are described and compared with those in previously reported cases. A discussion based on a literature review of the mode of inheritance, of variation in the clinical expression, and of the etiology of hearing loss is also included. Finally, we review and discuss the subdivision of this syndrome into the 2 types (I and II).

Otopalatodigital syndrome spectrum disorders: otopalatodigital syndrome types 1 and 2, frontometaphyseal dysplasia and Melnick-Needles syndrome

“…An autosomal recessive condition has been reported as an instance of OPD1, but the digital malformations are distinct, and as such it does not represent a true phenocopy of the disorder. 39 Germline mosaicism has been documented for OPD1 and therefore the risk of sib recurrence when the mother has tested negative for the causative FLNA mutation is higher than the background new mutation rate.…”

Distraction in a case of otopalatodigital syndrome type II

“…The term otopalatodigital syndrome was first used by Dudding [2]. However, it was Smith who emphasized the genetic and embryologic aspects of the syndrome, along with clinical details [3]. According to him, features of the syndrome included moderate conductive hearing loss, facial bone hypoplasia, cleft palate, partial anodontia, short stature, mild mental retardation, and dysplasia of the toes and phalanges.…”

Cleft lip in oto‐palato‐digital syndrome type I

“…3 Typically, OPD presents as a clinical triad of hearing impairment, cleft palate, and malformations of extremities, with characteristic facial appearances including hypertelorism, downslanting palpebral fissures, and frontal bossing. 3,4 The causative gene of OPD type I is known to be responsible for a group of clinically overlapping human syndromic or OPD-spectrum disorders; meanwhile, atypical manifestations have still been reported.…”

“…The most salient clinical features are characteristic facies and abnormal digits, which are considered to be associated with hearing impairment. 4 OPD is one of the OPD-spectrum disorders, which shows generalized skeletal dysplasia with multiple anomalies, such as OPD I and OPD II, Melnick-Needles syndrome (MNS), and frontometaphyseal dysplasia. 2 As differential diagnosis, oro-facio-digital syndrome and MNS are known to have anomalies with palate, faces, and digits, but these inheritance are X dominant and be concluded to lethal male.…”