Hair changes due to zinc deficiency in a case of sucrose malabsorption

A 7-year-old girl suffering from chronic diarrhoea due to sucrase deficiency was referred because of poor hair growth. Her scalp hair had a poor, colourless appearance and was much thinned in the occipital region. Her skin was dry, but otherwise normal. P-zinc was low (7.9 mumol/l), whereas P-albumin was normal. Oral zinc therapy, 40 mg daily, had a marked beneficial effect on her scalp hair, eyebrows and eyelashes, which became thicker and pigmented. Beau lines appeared on thumb-nails and 4th left finger-nail. A rise in P-zinc and S-alkaline phosphatase levels was observed during the zinc supplementation. Microscopic examination of her poor scalp hair, using polarized light, revealed well-defined abnormalities of the hair shafts, as reported by others in a case of acrodermatitis enteropathica: 1) a marked individual variation in diameter, 2) narrowing often associated with waving or sharp bending and broken ends, 3) striation with a tendency to trichonodosis. Such changes were absent in the pigmented hair appearing after the start of zinc therapy.