Yuan Y, et al. - In this study, quantification of the levels of a series of cytokines and neutrophils was done in order to determine the link between latent Propionibacterium acnes infection and chronic inflammation in degenerated intervertebral discs. An association was evident, of latent P. acnes infection with chronic inflammation in degenerated intervertebral discs. This link was especially seen in the samples with visible bacteria in histology, which manifested as increased numbers of cytokines and neutrophils. Possibly due to P. acnes-related chronic inflammation, much severer disc degeneration was observed in discs with P. acnes infection.