The Nesting Doll of Cutibacterium acnes Clonality

Area of Science:

• Clinical Microbiology
• Infectious Diseases
• Orthopedic Surgery

Background:

• Cutibacterium acnes (C. acnes) is a common cause of orthopedic implant infections, particularly after shoulder arthroplasty.
• Revision shoulder arthroplasty cases often involve persistent or recurrent infections potentially linked to C. acnes.
• The assumption of clonality in C. acnes isolates from deep tissue specimens may influence treatment and diagnostic strategies.

Purpose of the Study:

• To retrospectively analyze the clonality of C. acnes isolates from deep tissue specimens in patients undergoing revision shoulder arthroplasty.
• To determine if C. acnes isolates from the same infected joint exhibit clonal or diverse subtypes.
• To challenge current laboratory practices regarding the assessment of C. acnes in deep joint tissues.

Main Methods:

• Retrospective analysis of C. acnes isolates.
• Collection of deep tissue specimens from patients during revision shoulder arthroplasty.
• Subtyping of C. acnes isolates to assess clonality.

Main Results:

• The clonality of C. acnes isolates from deep tissue specimens in revision shoulder arthroplasty cannot be assumed.
• Multiple subtypes of C. acnes were identified in deep tissues around infected joints.
• The presence of multiple C. acnes subtypes is consistent with carriage on skin pilosebaceous follicles.

Conclusions:

• Findings challenge the assumption of clonality for C. acnes in deep joint tissues.
• Further assessment and specific testing for C. acnes isolates from infected joints may be warranted.
• Consideration of C. acnes subtype diversity is important for accurate diagnosis and management of shoulder arthroplasty infections.