Chilblain lupus erythematosus--a review of literature.

Chilblain lupus erythematosus (CHLE) is a rare, chronic form of cutaneous lupus erythematosus. Sporadic cases and two families with autosomal dominant-inherited CHLE have been reported. In familial CHLE, two missense mutations in TREX1 encoding the 3'-5' repair exonuclease 1 were described in affected individuals. The pathogenesis of sporadic CHLE remains unknown. Up to 20% of patients develop systemic lupus erythematosus (SLE). An association with anorexia is discussed. In many cases, there is good response to symptomatic therapy. SLE therapeutics have good effects on SLE-typical symptoms but not on chilblains themselves. This article reviews the clinical presentation, pathogenesis, diagnosis and treatment of CHLE. As an index patient with unique features, we report a 13-year-old boy developing CHLE after anorexia nervosa. Sequencing of TREX1 was normal. With psychotherapeutic support for anorexia and after antibiotic therapy, topical steroids, physical warming and calcium channel blockers, the patient experienced significant relief. Improvement of phalangeal perfusion was demonstrated by angio-MRI.