Genetic diseases acrodermatitis enteropathica

Zinc deficiency occurs in a rare genetic disease, acrodermatitis enteropathica. The disease develops in the early months of life, produces pigmented areas on the elbows, knees, face, and buttocks, and is fatal if left untreated. The disease results from an impairment in zinc absorption. Intestinal disturbances, diarrhea, and growth failure also occur. The disease can be treated successfully by administering oral zinc at two times the RDA (Grider and Yoimg, 1996). 

Another zinc deficiency disease, acrodermatitis enteropathica, may be a genetically determined disorder of zinc absorption. Soon after weaning from breastfeeding babies develop progressive pustular dermatitis combined with severe gastrointestinal disturbances. Through zinc supplementation the children become free of symptoms [48,49]. 

Although genetic defects in the metahoUsm of trace elements are rare, they are nonetheless important because of the information they have provided as to homeostatic control mechanisms. This in turn has led to development of effective therapeutic strategies. The most commonly investigated disorders are those affecting iron (hemochromatosis), copper (Wilson s disease and Menkes syndrome), zinc (acrodermatitis enteropathica), and molybdenum (molybdenum cofactor disease). 

Supplementation in genetically determined trace metal deficiency [48], e.g., hypo- or atransferrinemia (Fe), acrodermatitis enteropathica (Zn), or Menkes disease (Cu). 

The absorption of many minerals is affected by other compounds present in the intestinal lumen. As discussed in section 4.5.1, a number of reducing compounds can enhance the absorption of iron, and a number of chelating compounds enhance the absorption of other minerals. For example, zinc absorption is dependent on the secretion by the pancreas of a zinc-binding hgand (tentatively identified as the tryptophan metabolite picolinic acid). Failure to synthesize and secrete this zinc-binding ligand as a result of a genetic disease leads to the condition of acrodermatitis enteropathica— functional zinc deficiency despite an apparently adequate intake. 

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