Templier I, Reymond J-L, Nguyen M-A, Boujet C, Lantuejoul S, Beani J-C, Leccia M-T
Service de Dermatologie, CHU Michallon, Grenoble.
Ann Dermatol Venereol. 2006 Apr;133(4):375-9. doi: 10.1016/s0151-9638(06)70919-x.
Clinical pictures resembling acrodermatitis enteropathica have been described in acquired zinc deficiency and deficiencies of other nutrients such as biotin, essential fatty acids and amino acids as well as biotin metabolism disorders. We describe the case of an infant with maple syrup urine disease who developed an acrodermatitis-like syndrome due to iatrogenic valine and isoleucine deficiency.
CASE-REPORT: A diagnosis of maple syrup urine disease was made in a 5-month-old infant girl with severe neurologic disorders with extremely high levels of the three branched-chain amino acids (leucine, valine and isoleucine) in plasma and urine. Seven days after the start of therapy with a diet excluding these branched-chain amino acids, plasma isoleucine and valine concentrations were low while plasma leucine remained elevated. At the same time, a periorificial and acral dermatitis appeared together with diarrhea. Serum zinc concentrations were normal. A diagnosis of acrodermatitis enteropathica-like syndrome secondary to isoleucine and valine deficiency was suspected. Valine and isoleucine supplementation resulted in rapid resolution of the eruption.
Several cases of acrodermatitis enteropathica-like eruptions resulting from therapeutic protein restriction diets have been described in infants with different aminoacidopathies. The accompanying dermatosis was associated with a raised plasma leucine/isoleucine ratio and/or isoleucine deficiency, or valine deficiency. While the exact pathogenesis of the skin lesions has not been established, these observations show that branched-chain amino acids are essential for normal growth and differentiation of keratinocytes. The essential role of isoleucine is further substantiated by the fact that its presence is critical in keratinocyte culture media, with growth arrest occurring upon its depletion.
在获得性锌缺乏以及其他营养素（如生物素、必需脂肪酸和氨基酸）缺乏以及生物素代谢紊乱的情况下，曾有类似肠病性肢端皮炎的临床表现被描述。我们报告一例患有枫糖尿症的婴儿，因医源性缬氨酸和异亮氨酸缺乏而出现了类似肢端皮炎的综合征。
一名5个月大的患严重神经功能障碍的女婴被诊断为枫糖尿症，其血浆和尿液中三种支链氨基酸（亮氨酸、缬氨酸和异亮氨酸）水平极高。在开始采用不含这些支链氨基酸的饮食治疗7天后，血浆异亮氨酸和缬氨酸浓度较低，而血浆亮氨酸仍处于升高状态。与此同时，患儿出现了口周和肢端皮炎以及腹泻。血清锌浓度正常。怀疑为继发于异亮氨酸和缬氨酸缺乏的类似肠病性肢端皮炎综合征。补充缬氨酸和异亮氨酸后皮疹迅速消退。
在患有不同氨基酸病的婴儿中，已有数例因治疗性蛋白质限制饮食导致类似肠病性肢端皮炎皮疹的病例被描述。伴随的皮肤病与血浆亮氨酸/异亮氨酸比值升高和/或异亮氨酸缺乏或缬氨酸缺乏有关。虽然皮肤病变的确切发病机制尚未明确，但这些观察结果表明，支链氨基酸对角质形成细胞的正常生长和分化至关重要。异亮氨酸的关键作用进一步得到证实，即在角质形成细胞培养基中其存在至关重要，缺乏时会导致生长停滞。
