Hair and skin disorders as signs of mitochondrial disease.

OBJECTIVE: To compare and explore the skin manifestations of mitochondrial disorders in 14 children with puzzling and unexpected cutaneous presentations. STUDY
DESIGN: One hundred forty children with mitochondrial disorders who had been under observation in our hospital for the last 10 years, were carefully examined by the same physicians. Skin and hair characteristics were investigated by the same dermatologist. All the children developed an early unexplained association of symptoms. Metabolic screening for abnormal oxidative-reduction in plasma and mitochondrial enzyme investigations confirmed the diagnosis of oxidative phosphorylation disorders.
RESULTS: Fourteen children with mitochondrial disorders (10% of the original cohort) developed specific hair and skin abnormalities. Their cutaneous manifestations were similar, and could be classified into four categories: hair abnormalities, rashes and pigmentation disorders, hypertrichosis, and acrocyanosis. In 3 cases, skin disorders constituted the puzzling and unexpected manifestations of mitochondrial disease. Respiratory chain deficiencies in the cultured skin fibroblasts of 3 patients and heteroplasmic mitochondrial DNA rearrangement in the skin fibroblasts of 1 patient indicated that mitochondrial disorders may be expressed in the skin.
CONCLUSION: Hair abnormalities and pigmented skin eruptions might belong to the broad spectrum of presenting symptoms of mitochondrial disease. The association of these dermatologic lesions with unrelated disorders should lead physicians to consider a diagnosis of mitochondriopathy as early as possible.