Erythema Nodosum Leprosum Reaction Masquerading as Rheumatoid Arthritis

Area of Science:

• Immunology
• Dermatology
• Infectious Diseases

Background:

• Erythema nodosum leprosum (ENL) is a Type 3 hypersensitivity reaction.
• ENL commonly manifests as transient skin lesions like papules, plaques, and nodules.
• Hansen's disease, also known as leprosy, can trigger immune reactions.

Observation:

• A 52-year-old female presented with polyarticular joint pain.
• Her symptoms were initially misdiagnosed and treated as rheumatoid arthritis (RA).
• Clinical examination revealed Hansen's disease with a Type 2 reaction.

Findings:

• The patient's joint pain was a manifestation of a Type 2 reaction in Hansen's disease, not RA.
• Misdiagnosis delayed the correct identification of leprosy and its associated complications.
• ENL can present with diverse symptoms, including joint pain, complicating diagnosis.

Implications:

• Highlights the importance of comprehensive clinical evaluation in diagnosing complex cases.
• Emphasizes the need to consider Hansen's disease in differential diagnoses for inflammatory conditions.
• Underscores the impact of delayed diagnosis on patient outcomes for leprosy and its reactions.