Work

A Diagnostic Challenge of A Two-Year Misdiagnosis of Erythema Induratum of Bazin As Erythema Nodosum

Year: 2026

Type: article

Abstract: (M. tb). EIB, a type of tuberculid, is characterized by recurrent sore nodules on the lower extremities, which can mimic other dermatologic disorders, such as erythema nodosum (EN), and may result in misdiagnosis and delayed treatment. The aim of this case report was to raise awareness of the diagnostic problem of EIB and the need for thorough diagnostic tools. We present a case of EIB in a 31-year-old woman who was misdiagnosed as EN for two years. On examination, she had several uncomfortable nodules on the distal anterior aspects of both lower legs and the dorsum of the right foot, some ulcerated and healing with hyperpigmentation. The tuberculin test was positive and histopathology showed lobular panniculitis with granulomatous inflammation, Langhans giant cells, epithelioid cells and caseous necrosis. Polymerase chain reaction testing revealed the presence of M. tb deoxyribonucleic acid. In addition, the sputum smear was positive for M. tb and the chest X-ray findings were consistent with pulmonary TB. The woman was diagnosed with EIB with pulmonary TB and her skin lesions improved significantly after two months of anti-tuberculosis treatment. This case highlights the importance of reconsidering the diagnosis of EN in patients with recurrent or ulcerating nodules despite treatment, particularly in TB-endemic settings, and emphasizes the role of histopathological evaluation in diagnosing EIB.

Source: Clinical Cosmetic and Investigational Dermatology

DOI: 10.2147/ccid.s643959