Childhood-onset porphyria cutanea tarda: successful therapy with low-dose hydroxychloroquine (Plaquenil).

We describe a 4-year-old girl with a spontaneous blistering disorder that was consistent with porphyria cutanea tarda (PCT). There was no familial history of the disease or any obvious causative factors present. Oral hydroxychloroquine (3 mg/kg) was given twice weekly along with vitamin E (200 U/d) as an antioxidant. Within 6 weeks, marked decreased blistering occurred and by 12 weeks no blistering was evident. Despite clinical improvement and tolerance of hydroxychloroquine, urinary uroporphyrin, aspartate aminotransferase, and ferritin levels continued to rise reaching peak levels at 16 weeks of therapy. Near total biochemical remission was observed at 40 weeks and all therapy was discontinued at 60 weeks.