Hypohydrotic ectodermal dysplasia: an unusual presentation and management in an 11-year-old Xhosa boy

Ectodermal dysplasia (ED) is an inherited disorder in which two or more ectodermally derived structures fail to develop, or are abnormal in development. Hypohydrotic ectodermal dysplasia (HED) or Christ-Siemens-Touraine syndrome, is an X-linked recessive syndrome with an incidence of 1/10,000 to 1/100,000 births. Because of its X-linked inheritance pattern, it is more common in males. HED is characterised by hypohydrosis (diminished perspiration), hypotrichosis (decreased amount of hair) and microdontia (small teeth), hypodontia (lack of development of one or more teeth) or adontia (total lack of tooth development). These patients present diagnostic and treatment challenges because of variable oral manifestations. This report describes an 11-year-old Xhosa boy, who was referred to the University Dental Faculty by his general medical practitioner because of hypodontia. General facial features included: frontal bossing, a depressed nasal bridge, 'butterfly' pattern of eczema over the nasal bridge to the malar process of each cheek, thinned out hair, loss of vertical dimension of face and dry skin. Intra-oral examination revealed hypodontia with peg-shaped anterior teeth and diastemas. Radiological examination revealed no developing permanent teeth or tooth buds. Diagnosis was confirmed by doing a sweat gland count. Management included oral hygiene instruction, fluoride treatments, construction of a partial lower denture and counselling about his condition with particular reference to the danger of hyperthermia and control of allergies.