Article Text
Abstract
Background Acrodermatitis enteropathica (AE) is a rare disease occuring mainly in infants. The clinical symptoms are periorificial and acral dermatitis, alopecia, diarrhoea. The cause of disease is nutritional zinc deficiency or inherited disorders of zinc absorption.
Objectives To clarify the role of genetic factors in the AE’s aetiology.
Methods We observed two children with AE by clinical, laboratory, instrumental examination and bidirect sequencing of all coding exons and adjacent intronic regions of SLC39A4 gene.
Results Case 1:Girl, 2,5 years old, with rash appeared at age of 21 months. Clinical findings were malnutrition, acral eczematous plaques, hair loss, weakness, mild hepatomegaly, joints pain, diarrhoea, moderate anaemia.
Case 2:Boy, 6 months old, suffering from classical phenylketonuria (PKU), getting special diet from the first week of life. Eruptions on the acral body areas appeared from the 4th month of age, regarded as atopic dermatitis and appointed corticosteroids with no effect at the place of residence. On admission the main symptoms were Cushing’s syndrome, rash with typical localization, diarrhoea, moderate anaemia, hypoalbuminemia.
The rare homozygous polymorphism c.473C>T in exon 02 of SLC39A4 gene leading to amino acid change p.T158M was revealed in both children. Besides the girl (case 1) also carried out heterozygous nucleotide substitution c.1220T>G leading to amino acid change p.L407R not described earlier.
The diet therapy consisted of: in case 1 partial parenteral and enteral nutrition, in case 2 PKU diet by use of hydrolyzed whey protein formula and an amino acid mixture without phenylalanine. Both children received zinc medications in enteral and parenteral forms, fat-soluble vitamins, topical ointment treatment. Children continued to receive zinc supplements after discharge. After 2 weeks there was a significant regression of lesions, stool normalisation, haemoglobin increase. Follow-up observation after 3 months showed normal nutritional status, absence of anaemia, the complete absence of skin lesions. The girl recovered hair growth.
Conclusions The detected rare nucleotide substitutions in SLC39A4 gene provide a basis to confirm the diagnosis and expand understanding of the AE aetiology. Multidisciplinary approach involving dermatologists, nutritionists and geneticists plays an important role in the AE diagnosis and treatment.