Incidence of Cutibacterium acnes in open shoulder surgery

Abstract

In recent years, Cutibacterium acnes (C. acnes) has been reported to affect postoperative outcomes. The purpose of this study was to examine the detection rate and clinical features of C. acnes infection after open shoulder surgery. Fifty-nine patients (33 males and 26 females; mean age, 69.1 years) were included. Samples were collected from a skin swab at the incision site prior to skin preparation. Further samples were collected from synovial swabs at the glenohumeral joint immediately after incision and before incision closure. Samples with C. acnes-positive skin swab cultures were defined as Group A, and those with negative cultures were defined as Group N. Age, sex, presence of diabetes mellitus, operation time, presence of deep infection after surgery, and rate of positive synovial swab cultures were compared between groups. There were 27 patients in Group A (mean age 69.1±13.3 [SD], 21 males and 6 females) and 32 patients in Group N (mean age 69.1±11.0 [SD], 12 males and 20 females). No significant difference in the presence of diabetes mellitus and operation time were found between groups. From the glenohumeral joint immediately after incision, C. acnes was detected in 22.2% and 0% of patients in Group A and Group N, respectively. For the glenohumeral joint before incision closure, C. acnes was detected in 22.2% and 0% of patients in Group A and Group N, respectively, demonstrating a significantly higher rate in Group A. Our findings suggest that the route of infection following open shoulder surgery is via contamination.

Keywords: cutibacterium acnes; incidence contamination; open shoulder surgery.

Fig. 1

Sites of sample collection Fig.1A: Deltopectoral approach; swab culture from the skin above the tip of the coracoid process. Fig.1B: Synovial swab culture, immediately after surgical exposure of the joint. Fig.1C: Synovial swab culture, immediately after surgical closure of the joint.

Fig. 2

Blood test results (preoperative and 2-week postoperative white blood cell count values) There were no significant differences in white blood cell values between the two groups in preoperative and 2-week postoperative blood tests.

Fig. 3

Blood test results (preoperative and 2-week postoperative C-reactive protein values) There were no significant differences in C-reactive protein values between the two groups in preoperative and 2-week postoperative blood tests.