Zinc Deficiency Associated with Hypothyroidism: An Overlooked Cause of Severe Alopecia
A 28-year-old woman presented with weakness, lack of appetite, diffuse hair loss, and asymptomatic scaly skin lesions of 2 months duration. There was no history suggestive of connective tissue disease or malabsorption. On physical examination, the patient appeared depressed. She had pallor and puffiness of the upper part of the face. There was diffuse, dry scaling over the face and extremities, along with annular, erythematous, scaly patches over the nape of the neck. The notable finding on the scalp was profound diffuse alopecia [] with marked hair loss over the occipital area []. There was also severe thinning of the hair of the eyebrows and eyelashes []. A hair pull test done from five different sites on the scalp was positive. Light microscopic examination of the hair revealed telogen type hair roots without any hair shaft abnormalities. Thyroid function tests were as follows: T3 70 ng/dl (normal 80-200), T4 2 mcg/dl (normal 4-12), and Thyroid Stimulating Hormone 64 IU/ml (normal 0.30-4.5). All routine investigations including antinuclear antibody profile were within normal limits, except for a low hemoglobin level of 9 g/dl. Histopathological examination of an annular scaly lesion showed minimal epidermal hyperplasia with a mild perivascular inflammatory infiltrate.\nThyroid hormone supplements were started, but the scaly lesions persisted and there was no detectable improvement in the hair loss. Since a definite diagnosis of the annular scaly lesions could not be made, plasma zinc level was estimated, which was 62 mcg/dl (normal 66-144 mcg/dl and optimal levels 90-150 mcg/dl).[] Zinc monohydrate 140 mg capsules containing 50 mg of elemental zinc was given twice a day, along with other multivitamins. One month later, the skin lesions had cleared completely, and there was such a remarkable improvement in her mental depression and facial puffiness, that her facies was totally unrecognizable when compared to her previous appearance []. Subsequent follow-up demonstrated complete regrowth of hair over a course of 4 months [].