A 1-year-old female with maple syrup urine disease presenting with erythematous, partially eroded plaques on the trunk, anogenital area, and extremities experienced metabolic crisis. The skin lesions appeared at 11 months of age and was thought to result from amino acid imbalance secondary to erratic supplementation of specialized milk formula devoid of isoleucine, leucine, and valine. Serial urine monitoring showed persistent ketones and elevated serum leucine and valine. The patient was managed with emollients, intralipid 20%, and addition of isoleucine and valine supplements to counter the neurotoxic effect of leucine. After 8 days of proper feeding and continuous emollient application, the lesions improved and skin biopsy revealed superficial perivascular dermatitis. Although a decrease in erythema and desquamation was noted, the patient had persistent cerebral edema and continued to deteriorate.