- Infectius Diseases
- Preventive Medicine
A 64-year-old man presented with a 2-year history of asymptomatic, widespread, erythematous-to-violaceous papules that were distributed symmetrically on his trunk, arms, and legs (Panel A). The papules coalesced to form annular plaques, especially on the forearms and dorsal surfaces of the hands (Panel B). Skin biopsy revealed palisading granulomatous inflammation that surrounded degenerating collagen within the dermis, findings that were consistent with a diagnosis of granuloma annulare. Laboratory tests revealed a fasting glucose level of 7.9 mmol per liter (142 mg per deciliter; normal range, 3.6 to 6.1 mmol liter [65 to 110 mg per deciliter]) and a postprandial glucose level of 12.1 mmol per liter (218 mg per deciliter; normal value, <7.8 mmol per liter [140 mg per deciliter]), findings that were consistent with a diagnosis of diabetes mellitus. Thyroid hormone levels and the blood-lipid profile were normal. Granuloma annulare is a benign, noninfectious, granulomatous skin disease that is usually asymptomatic and self-limited. Granuloma annulare is often localized and not associated with systemic disease, although it can be triggered by trauma, infection, drugs, and metabolic derangement. This patient presented with the less common generalized variant of granuloma annulare, which is often associated with diabetes mellitus or thyroid disease. Four months after the patient began tight glucose control and treatment with oral hydroxychloroquine, the skin lesions had markedly regressed, without scarring.