Acrodermatitis enteropathica: Case report analyses of zinc metabolism electron microscopic examination and immune function

Abstract

Acrodermatitis enteropathica (AE) is a rare autosomal recessive disease that results from an unknown defect in zinc metabolism and usually occurs in the first year of life. Zinc is required for the structure and activity of ∼300 metalloenzymes. Therefore, every system could be affected functionally or structurally by this defect. An 11-year-old girl presented with rashes around mucocutaneous junctions, periorbital and perianal areas, and on the extremities. These clinical signs and symptoms had started when she was 3.5 months old. She was the third child of healthy parents who are second cousins. One of her brothers had died with similar manifestations when he was 3 years old. In the initial physical examination, growth retardation, partial alopecia, squamous skin eruptions around the body orifices, pustular lesions on her knees and hands, dystrophic changes of the finger and toe nails, and taste dysfunction were prominent findings. Laboratory results revealed: haemoglobin: 12.3 gr/dl; WBC: 7,300/mm3; platelet count : 402,000 /mm3; serum iron : 152 μg/dl; total iron binding capacity : 501 μg/dl; transferrin saturation : 25.1 %; serum cu level: 118 μg/dl (123–187 μg/dl); and alkaline phosphatase :18 IU/L (98–279 U/L ). Serum electrolytes, hepatic, and renal function tests were normal. Zinc levels in different body compartments were decreased (plasma Zn: 20 μg/dl; erythrocyte Zn: 5.7μg/ml; hair Zn: 116.6 μg/g) with normal zinc absorption. Zinc 65 absorption and retention test showed initial elevation, but decreased rapidly after the fourth day compared to the controls and her other family members. By electron microscopy, intestinal mucosal biopsy revealed Paneth cell inclusions. Lymphocyte subpopulations and results of neutrophil chemotaxis also showed some abnormalities. Pathological clinical findings and symptoms totally disappeared in a few weeks with oral zinc therapy (ZnSO4, 2 mg/kg/day). J. Trace Elem. Exp. Med. 13:317–325, 2000. © 2000 Wiley-Liss, Inc.