Discussion
RHS is considered one of the groups of disorders categorized by findings
of ectodermal dysplasia and clefting. It’s generally inherited in an
autosomally dominant fashion but sporadic mutations do occur as in our
case (3). There is increasing evidence that symptoms of RHS are caused
by defects in the transcription factor p63 (4).
The palate, hair, eyes and nails are the four areas particularly
affected (1). Cleft palate is the cardinal feature of this syndrome
(1,5). Our patient’s cleft palate was repaired in childhood.
Patients commonly had blond coarse, wiry, woolly, fine, dry, slowly
growing, short hair or hypotrichosis. They showed stiff, uncombable,
brittle and kinky hair with a “steelwool appearance”, breaking by
combing, furthermore lusterless, soft, thick or thin hair (4). Hair loss
at puberty is also a reported characteristic (6). This feature was
observed in our patient and he is now alopecic with a few fragile,
sparse hairs. The craniofacial features, including high forehead, narrow
nose, thin upper lip and hypoplastic maxilla, with a high arched palate
seem to be typical for this ED syndrome (4). Hypodontia and malformation
are frequently observed in RHS leading to esthetic and psychological
problems (4). There are good possibilities using removable prostheses to
help these children. Patients commonly had onychodysplasia and
hypoplastic nails (5), as reported in our patient.
Hidrotic ED, the most common form of ED, occurs in ~1 in
5000–10 000 births. Our patient had an hidrotic ED with bilateral
palmoplantar keratoderma and occasional ulcerations on the palms.
Palmoplantar keratoderma is a common but not universal feature of
hidrotic ED which increases in severity with age (6). It’s most often
linked to heterozygous mutations in GJB6, gap junction beta-6 protein
(Connexin 30) (7). However, a literature search revealed only five
reports of palmoplantar keratoderma in hypohidrotic ED (8–10). It is
considered an uncommon manifestation of Hidrotic ED. Ulcerations on the
palms as in our patient are not common in RHS. O’Donnell BP et al
reported the case of a 24-year-old woman with RHS, she had occasional
bilateral ulceration on the palms too (11).