Molecular detection of Propionibacterium acnes in biopsy samples of intervertebral disc with modic changes in patients undergoing herniated disc surgery

BACKGROUND AND OBJECTIVES: Recent studies have hypothesized that sterile disc infection with the anaerobic Propionibacterium acnes, recently renamed Cutibacterium acnes, occurs in people with intervertebral disc (IVD) herniation. This study aimed to examine the presence of P. acnes in patients who have Low back pain (LBP) with Modic changes observed in their Magnetic Resonance Imaging (MRI). MATERIALS AND METHODS: Thirty-seven patients who were candidates for surgery due to disc herniation and demonstrated Modic changes in MRI were included in the study. Before the surgery, the level of pain in patients was assessed using the visual analog score (VAS). All patients were asked to fill in the Oswestry Low Back Pain Disability Questionnaire. Intervertebral disc changes observed in MRI were recorded for all patients. Then, during surgery, sterile intervertebral disc samples were taken. P. acnes detection was performed using PCR in the laboratory. Data analysis with Chi-squared test, independent samples t-test, and Mann-Whitney U test in SPSS 18.0. RESULTS: The mean age of 37 patients equaled 43.64 years and the mean duration of symptoms was 11.05 months. In molecular examination, of the 37 individuals, the genome of P. acnes was positive in 23 cases (62.2%) and negative in 14 (37.8%). The relationship between VAS, disability score, changes in MRI, and patients’ age with the positivity of the intervertebral disc sample was also assessed. Of these variables, only age was significantly correlated with the positive molecular finding, such that with an increase in age, the probability of positive findings was increased (p = 0.022). CONCLUSION: Based on the results, lumbar disc infection with P. acnes may play a significant role in causing Modic changes and the progression of the disease in patients with LBP.