Erythema Induratum of Bazin Associated With a Negative Tuberculin Test: A Case Report.

Bazin's indurated erythema is a chronic lobular panniculitis associated with a hypersensitivity reaction to Mycobacterium tuberculosis. It is characterized by recurrent painful subcutaneous nodules and ulcerative lesions on the lower extremities. We present a 39-year-old male with a one-year history of unintentional weight loss and intermittent evening fever. During this period, the patient developed progressively evolving erythematous cutaneous lesions located on the lower extremities, along with multiple painful, indurated subcutaneous nodules exhibiting a chronic recurrent course with occasional ulceration. Histopathological evaluation of a skin biopsy revealed granulomatous lobular panniculitis consistent with erythema induratum of Bazin. It is a rare tuberculid presentation, representing a cutaneous manifestation of hypersensitivity to tuberculosis, and is more frequently observed in women. It presents a diagnostic challenge due to its similarity to other inflammatory and infectious dermatoses. The diagnosis is clinical and histopathological, with findings typically demonstrating granulomatous lobular panniculitis and vasculitis. This case highlights the early recognition in tuberculosis-endemic regions, as early initiation of antituberculosis treatment is associated with significant clinical improvement.