[Lipoatrophic panniculitis in adults: treatment with hydroxychloroquine]

Lipoatrophic panniculitis is generally considered to be a rare disease affecting children. We report a case involving this condition in an adult patient presenting with striking clinical features and responding to hydroxychloroquine therapy. We discuss the nosological relationship between lipoatrophic panniculitis and connective tissue panniculitis.

A 62-year-old woman was referred to our institution with a six-month history of painful erythematous nodules and plaques on the calves, thighs, buttocks, breasts, abdomen and arms. With each outbreak of new lesions, she felt unwell and experienced fever, chills and sweating. After a few weeks, the lesions progressed circumferentially and led to large areas of subcutaneous atrophy showing a central depression covered with a yellowish, supple skin and surrounded by an annular, infiltrated, erythematous and tender inflammatory margin. Deep subcutaneous biopsy specimens showed typical features of lobular and septal lipophagic panniculitis, with a dense inflammatory infiltrate composed of large histiocytes, multinucleated giant cells and few neutrophils, without vasculitis. The patient was started on hydroxychloroquine 400 mg daily. Three weeks later, her pain and tenderness had completely resolved and the inflammatory margin of the lesions had clearly regressed.

This unique condition, with distinctive clinical and histological features, is similar to cases described under the term "lipophagic panniculitis", seen mostly in children, but also "connective tissue panniculitis". Their clinical resemblance and response to hydroxychloroquine therapy leads us to think that these two entities, previously subsumed under the eponym of Weber-Christian disease or Rothman-Makai syndrome, are closely related.

Dermatologists and dermatopathologists should be made aware of this unusual entity, and of the fact that it can arise in adult patients, so that they may make an early diagnosis and thus prevent the unsightly consequences of lipoatrophy.