Immunohistochemical Detection of Propionibacterium acnes in the Retinal Granulomas in Patients with Ocular Sarcoidosis

Abstract

The etiology of sarcoidosis is still obscure; however, Mycobacteria and Propionibacterium acnes are considered the most implicated etiological agent for sarcoidosis. To investigate whether P. acnes is an etiological agent for sarcoid uveitis, we analyzed the frequency of P. acnes detected within the biopsied retinas from patients with ocular sarcoidosis by immunohistochemistry with a P. acnes-specific monoclonal antibody (PAB antibody). Eleven patients (12 eyes) with sarcoid uveitis were enrolled in this study. Eight patients with rhegmatogenous retinal detachment, two patients with non-sarcoid uveitis, and two patients with vitreoretinal lymphoma were enrolled as controls. In the sarcoidosis group, granulomas were mainly observed in the inner retinal layer filled with CD4+ cells and CD68+ cells, indicating the Th1 immune response. P. acnes, identified as round bodies that reacted with the PAB antibody, were present in 10/12 samples (83%) from 9/11 patients (82%) with sarcoidosis. These round bodies were scattered within the retinal granulomas mainly in the inner retinal layer. In the control group, no round bodies were detected. Our results suggested that P. acnes could be associated with sarcoid uveitis. We hypothesize that sarcoid granulomas may be formed by a Th1 immune response to P. acnes hematogenously transmitted to the retina.

Propionibacterium acnes-associated chronic hypertrophic pachymeningitis followed by refractory otitis media: a case report

“…It is well known for its involvement in the pathogenesis of acne vulgaris [19]; moreover, its role in various postoperative infections such as endocarditis, endophthalmitis, and central nervous system (CNS) infections has been reported [5]. In addition, P. acnes can invade and persist in epithelial cells and circulating macrophages in its intracellular latent form [5], which results in chronic inflammation such as sarcoidosis [6,20,21].…”

Noninfectious uveitis in the Asia–Pacific region

“…Studies increasingly suggest that the immunopathogenesis of sarcoidosis is highly associated with environmental and acnes DNA were significantly higher in granulomatous areas than that in nongranulomatous areas in sarcoid lymph nodes [80]. Other studies have confirmed this finding [81],.…”

Environmental Risk Factors for Sarcoidosis

“…This microorganism is the only one that has been cultured from sarcoidosis lesions ( 58 , 59 ). Numerous studies have identified specific immune responses to Propionibacterium acnes in sarcoidosis patients but much less to none in non-sarcoidosis controls ( 52 , 60 , 61 ). Propionibacterium acnes was highly associated with sarcoidosis in a meta-analysis of studies evaluating infectious agents as a cause of the disease ( 47 ).…”