Acrodermatitis Enteropathica

Abstract

A 6-month-old girl presented with recent onset skin lesions, hair loss, and diarrhea, which started at age 4 months. She was the first born child of a consanguineously married couple and was exclusively breast fed up to 3 month of age and was weaned thereafter. On examination, the child was irritable, weighed 5.5 kg and had a length of 60 cm (<3rd percentile). Cutaneous examination revealed erythematous erosive plaques with scaling and crusting at periphery involving scalp, perioral, anogenital area, and distal extremities (Figure 1 and Figure 2). Diffuse alopecia of the scalp was also noted. Based on the above findings, the diagnosis of acrodermatitis enteropathica was considered and was further supported by her low plasma levels of zinc (10 μg/dL; reference range, 50-150 μg/dL) and alkaline phosphatase (15 U/L; reference range, 42-128 U/L).Figure 2Involvement of anogenital area.View Large Image Figure ViewerDownload Hi-res image Download (PPT) Zinc is an essential trace element which acts as a cofactor of various enzymes such as alkaline phosphatases, alcohol dehydrogenase, RNA polymerase, and other digestive enzymes.1Maverakis E. Fung M.A. Lynch P.J. Draznin M. Michael D.J. Ruben B. et al.Acrodermatitis enteropathica and an overview of zinc metabolism.J Am Acad Dermatol. 2007; 56: 116-124Abstract Full Text Full Text PDF PubMed Scopus (280) Google Scholar Zinc deficiency can be inherited or acquired. Inherited deficiency of zinc, also known as acrodermatitis enteropathica occurs owing to partial or complete deficiency of zinc ligand-binding protein, which is encoded by SLC39A4 (solute carrier family 39 member 4) gene on chromosome 8q24.3.2Kury S. Dreno B. Bezieau S. Giraudet S. Kharfi M. Kamoun R. et al.Identification of SLC39A4, a gene involved in acrodermatitis enteropathica.Nat Genet. 2002; 31: 239-240Crossref PubMed Scopus (423) Google Scholar Causes of acquired deficiency includes prematurity, low birth weight, maternal zinc deficiency, poor feeding, malabsorption syndromes, low calcium and phytate diet, and kwashiorkor.3Perafan-Riveros C. Franca L.F. Alves A.C. Sanches Jr., J.A. Acrodermatitis enteropathica: case report and review of the literature.Pediatr Dermatol. 2002; 19: 426-431Crossref PubMed Scopus (121) Google Scholar Zinc deficiency presents with a triad of periorificial dermatitis, diarrhea, and alopecia but the complete triad is seen in only 20% of patients.4Van Wouwe J.P. Clinical and laboratory assessment of zinc deficiency in Dutch children. A review.Biol Trace Elem Res. 1995; 49: 211-225Crossref PubMed Scopus (53) Google Scholar The cutaneous lesions are characterized by symmetric erythematous eczematous or psoriasiform plaques around orifices and acral areas which can be accompanied by diffuse alopecia, canities, loss of eyelashes and eyebrows, glossitis, gingivitis, stomatitis, and nail manifestations.3Perafan-Riveros C. Franca L.F. Alves A.C. Sanches Jr., J.A. Acrodermatitis enteropathica: case report and review of the literature.Pediatr Dermatol. 2002; 19: 426-431Crossref PubMed Scopus (121) Google Scholar,5Vinay K. Yadav S. Handa S. Zinc deficiency and canities: an unusual manifestation.JAMA Dermatol. 2014; 150: 1116-1117Crossref PubMed Scopus (4) Google Scholar Apart from diarrhea, other extracutaneous features includes irritability, lethargy, growth retardation, photophobia, blepharitis, and conjunctivitis. Diagnosis is mainly clinical and it can be confirmed by a low serum zinc level and response to treatment. Inherited deficiency should be suspected in presence of family history, or relapse after stopping zinc supplementation. However, genetic testing is required for confirmation. Treatment includes zinc supplementation at a dose of 3 mg/kg of elemental zinc.