Truncal necrobiosis lipoidica diabeticorum: A first case report

Necrobiosis lipoidica (NL) is a known chronic rare granulomatous dermatitis. NL typically occurs in the lower extremity, there have only been previously reported cases of NL on the face, scalp, forearms, and dorsum of the hands. However, truncal NL is not a typical location.

A 67-year-old man known to have diabetes type 2, presented with a 3-year history of painful and itchy skin lesions on the right lateral chest wall. On clinical examination, he had a red discolored patch with superficial capillaries and yellow discoloration at the center. Based on the histological examination, necrobiosis lipoidica was confirmed. Initial treatment with clobetasol propionate, tacrolimus, and topical corticosteroid cream was unsuccessful, and further NL lesions developed on the lower limb.

NL rash is characterized by its location in the lower limbs and rarely involves fingers, hands, scalp, or face. It is noteworthy that the patient presented with NL skin lesions bon the trunk, which is outside the usual presentation. The prevalence of NL ranges from 0.3% to 1.2% among patients with diabetes mellitus. The treatment of NL is usually difficult. Initial management includes smoking cessation and proper diabetes control. In addition, intralesional and topical corticosteroids might be effective. In this case report, there was no improvement in NL despite the use of topical corticosteroids.

Immediate diagnosis and treatment of NL may prevent disease progression; therefore, the diagnosis of NL should be considered, even in an unusual location.