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Author Spotlight: Exploring the Role of Inflammation in the Co-occurrence of Primary Sjogren's Syndrome and Lung Adenocarcinoma
Published on: September 20, 2024
Propionibacterium acnes-associated sarcoidosis complicated by acute bird-related hypersensitivity pneumonitis
Michiru Sawahata1, Noritaka Sakamoto2, Hideaki Yamasawa3
1Division of Pulmonary Medicine, Department of Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, 329-0498, Japan. sawahata@jichi.ac.jp.
Background:
The number of reports on sarcoidosis complicated by hypersensitivity pneumonitis (HP) is limited, and most describe cases complicated by chronic bird-related HP. Here, we present for the first time a case with Propionibacterium acnes-associated sarcoidosis complicated by acute bird-related HP.
Case Presentation:
A 62-year-old man with a past medical history of sarcoidosis was admitted to our department, and chest computed tomography showed diffuse ground-glass opacities, which appeared as he rapidly increased the number of pigeons he kept for a competition. Random transbronchial lung biopsy revealed well-formed non-caseating epithelioid granulomas, which contained positively stained substances on immunohistochemistry using the PAB antibody, a specific monoclonal antibody against P. acnes lipoteichoic acid. Poorly formed non-caseating granulomas without positively stained substances were also detected.
Conclusion:
We describe the successful identification of this exceptionally rare case of sarcoidosis complicated by acute bird-related HP in which two morphologically and immunohistologically different types of granulomas were present in the same lung.
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