[Pulmonary sarcoidosis developing during treatment with etanercept]

Area of Science:

• Rheumatology
• Pulmonology
• Immunology

Background:

• Tumor necrosis factor (TNF) blockers are standard treatments for inflammatory rheumatic diseases and extrapulmonary sarcoidosis.
• TNFα is crucial in sarcoid granuloma formation, but anti-TNF therapies have been linked to granulomatosis resembling sarcoidosis.

Observation:

• A patient with ankylosing spondylitis on etanercept developed pulmonary nodules and infiltrates.
• Bronchoalveolar lavage ruled out infection, and lung biopsy revealed non-caseating granulomata consistent with sarcoidosis.
• Symptoms persisted after etanercept discontinuation, improving only after corticosteroid introduction.

Findings:

• This case report details a patient developing pulmonary sarcoid-like granulomatosis during anti-TNF therapy.
• Diagnosis was confirmed via lung biopsy, showing non-caseating granulomata.
• The patient required corticosteroids for symptom resolution.

Implications:

• Clinicians must consider sarcoid-like granulomatosis as a potential pulmonary complication of TNF blockers.
• Excluding tuberculosis is critical, but sarcoid-like reactions should be investigated.
• Further study of anti-TNF therapy's pulmonary effects is warranted, with 23 prior cases documented.