Atypical presentation of neuropsychiatric lupus with acanthosis nigricans.

Cutaneous manifestations are commonly observed in pediatric patients with systemic lupus erythematosus. Acanthosis nigricans, however, is rarely reported, and even less often in association with neuropsychiatric manifestations of lupus erythematosus. We describe a 9-year-old boy with acute behavioral and cognitive deterioration, combined with cutaneous, diffuse hyperpigmented and hyperkeratotic plaques. Cerebral magnetic resonance imaging revealed cortical atrophy and white matter abnormalities involving the fornix, corpus callosum, and parieto-occipital periventricular regions. The presence of progressive cognitive and behavioral deterioration, combined with abnormal white matter signals on magnetic resonance imaging, led us to suspect X-linked adrenoleukodystrophy. The subsequent development of systemic signs, together with positive serologic tests, confirmed the diagnosis of neuropsychiatric lupus with acanthosis nigricans. We review the literature on acanthosis nigricans in systemic lupus erythematosus and the value of magnetic resonance imaging in evaluating patients with neuropsychiatric systemic lupus.