Findings from the patient's skin biopsy demonstrated distention of the upper follicular ostia with prominent keratotic plugging. The patient's multivitamin supplementation had been recently changed to omit vitamin A. Two-month supplementation increased his serum vitamin A level to 67 μg/dL and resolved his eruption and vision abnormalities.
Phrynoderma is classically thought to result from severe vitamin A deficiency,1-5 although deficiencies in vitamins B6 and E7 essential fatty acids and severe malnutrition8 have also been implicated. Severe vitamin A deficiency may also result in conjunctival and corneal lesions and nyctalopia (night blindness).1