TY - JOUR T1 - Presence of <em>Propionibacterium acnes</em> in granulomas associates with a chronic disease course in Dutch sarcoidosis patients JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.00486-2020 VL - 7 IS - 1 SP - 00486-2020 AU - Els Beijer AU - Kees Seldenrijk AU - Yoshinobu Eishi AU - Keisuke Uchida AU - Jan Damen AU - Jan C. Grutters AU - Marcel Veltkamp Y1 - 2021/01/01 UR - http://openres.ersjournals.com/content/7/1/00486-2020.abstract N2 - Several studies demonstrated that Propionibacterium acnes may be involved in sarcoidosis pathogenesis. Presence of P. acnes was found in granulomas of the majority of Japanese sarcoidosis patients. However, presence of P. acnes in tissue has never been related to sarcoidosis phenotypes and clinical outcome. Therefore, the aims of our study were to demonstrate whether P. acnes can be detected in granulomas of Dutch sarcoidosis patients and to investigate whether its presence is related to a clinical phenotype and/or course of disease.Sections of formalin-fixed paraffin-embedded tissue blocks of 76 sarcoidosis patients were examined by immunostaining with a P. acnes-specific monoclonal antibody (PAB antibody) using a Ventana BenchMark ULTRA. Clinical outcome status (COS) was determined and classified into two phenotype groups: A: resolved, minimal or persistent disease without treatment (COS 1–6) and B: persistent disease with need for treatment (COS 7–9).P. acnes was detected in samples of 31 patients (41%) and located within granulomas in samples of 13 patients (17%). The frequency of P. acnes detected in granulomas at diagnosis was significantly higher in patients with phenotype B compared to patients with phenotype A (29% versus 0%, p=0.021).Presence of P. acnes in granulomas can be confirmed in Dutch sarcoidosis patients. It is intriguing that presence of P. acnes in granulomas is more frequently found in patients with chronic disease requiring treatment. This adds to the rationale that a subgroup of sarcoidosis patients might benefit from antibiotic therapy.Significantly more sarcoidosis patients with a chronic disease course requiring treatment have presence of P. acnes in granulomas. This contributes to the premise that it is relevant to further explore antibacterial therapy in sarcoidosis. https://bit.ly/36wCbbw ER -