Pathology · single question
Which of the following is a recognised feature of hypohidrotic ectodermal dysplasia?
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Correct answer: A. Dry eyes from absent or hypoplastic lacrimal glands
- A. Correct. Hypohidrotic (anhidrotic) ectodermal dysplasia affects all ectodermally-derived structures. The classic triad is HYPODONTIA/ANODONTIA with conical teeth, HYPOTRICHOSIS (sparse fine hair), and HYPOHIDROSIS (absent or reduced sweat glands, causing heat intolerance and life-threatening hyperthermia in infancy). Because lacrimal, salivary, sebaceous and mucous glands are also ectodermal, patients have DRY EYES, xerostomia, dry nasal mucosa and dry skin. Periorbital hyperpigmentation and frontal bossing complete the picture.
- B. Incorrect. Macroglossia is a feature of Down syndrome, hypothyroidism, Beckwith-Wiedemann syndrome and amyloidosis — not ectodermal dysplasia.
- C. Incorrect. Head circumference is normal. The facial appearance — frontal bossing, saddle nose, protuberant lips — is characteristic but does not include microcephaly.
- D. Incorrect. The dental problem is failure of teeth to FORM (hypodontia/anodontia with conical or peg-shaped remaining teeth), not loss of formed teeth to periodontal disease. Early tooth loss from aggressive periodontitis suggests Papillon-Lefèvre or hypophosphatasia instead.