Serum Specific Antibodies Do Not Seem to Have an Additional Role in the Diagnosis of Hypersensitivity Pneumonitis

Background: We aimed to investigate the contribution of serum immunoglobulin G testing to the history of exposure in diagnosing fibrotic hypersensitivity pneumonitis. Methods: A single-center, retrospective, cross-sectional study recruited 63 patients diagnosed with fibrotic hypersensitivity pneumonitis in line with the guidelines of the American Thoracic Society. Descriptive statistics were presented, and Kappa statistic was performed to evaluate the compatibility between the panel and the history of exposure. Results: The median age was 63 (22-81) years, and 34 (54%) were male. Forty-six patients (73%) had a positive history of exposure. Thirty-nine patients (61.9%) had a positive HP/Avian panel. The most common exposure agent was mold (34.9%), followed by parakeet (31.7%). The antibody most frequently detected was Penicillium chrysogenum lgG (36.5%), followed by Aspergillus fumigatus (31.8%). There was no compatibility between the HP/Avian panel and history of exposure (kappa coefficient=0.18, p=0.14). When exposure was only based on the history, 9 (14.3%) patients were diagnosed with fibrotic hypersensitivity pneumonitis with moderate confidence, 11 (17.5%) with high confidence, and 43 (68.3%) with definite confidence, whereas if exposure was evaluated with history and panel, 9 (14.3%) patients were diagnosed as fibrotic hypersensitivity pneumonitis with moderate confidence, 9 (14.3%) patients with high confidence and 45 (71.4%) patients with definite confidence. Conclusions: Serum-specific precipitating antibody panel does not provide additional value to the history of exposure in diagnosing fibrotic hypersensitivity pneumonitis.