Quantification of the antibody response to Propionibacterium acnes in a patient with prosthetic valve endocarditis: – a case report

Abstract

BackgroundThe isolation of Propionibacterium acnes in blood cultures is often considered a contaminant. On rare occasions, P. acnes can cause severe infections, including endocarditis and intravascular prosthesis-associated infections. To evaluate the discrimination between a contaminant and a clinically relevant infection we used an Ouchterlony test system to quantify the antibody response to P. acnes in a patient with a proven P. acnes endocarditis.Case presentationWe report on a 64-year-old Caucasian man who developed P. acnes endocarditis four years following a composite valve-graft conduit replacement of the aortic root. Bacterial growth in blood cultures was detected after an incubation period of 6 days. However, the antibody titer to P. acnes was 1:8 at the time of diagnosis and declined slowly thereafter over 2½ years. The patient’s response to the antibiotic treatment was excellent, and no surgical re-intervention was necessary.ConclusionThe working hypothesis of infective endocarditis can be substantiated by serologic testing, which, if positive, provides one additional minor criterion. Moreover, quantification of the antibody response to P. acnes, though not specific, may assist in the differentiation between contaminants and an infection. This quantification may have implications for the patient management, e.g. indication for and choice of the antibiotic therapy.

Susceptibility of Enterococcus faecalis and Propionibacterium acnes to antimicrobial photodynamic therapy

“…P. acnes, by its turn, is an opportunistic pathogen highlighted in the literature by being considered the main causative microorganism of acne vulgaris [39], a chronic skin disease that can result in disfiguring scars, usually accompanied by severe psychological impact on patients [40]. To a minor extent, P. acnes is also related to other infections, including osteomyelitis, endophthalmitis, endocarditis, joint prostheses infections, and endodontic infections [41][42][43][44]. In recent years, reports revealing increasing antimicrobial resistance of P. acnes to antimicrobials used for the treatment of acne vulgaris have grown in number [45].…”

Double‐Immunodiffusion Assay for Detecting Specific Antibodies (Ouchterlony)

“…Nevertheless, it is simple and inexpensive, and has the ability to distinguish antigenic differences and perform simple quantitation of antigens as well. Originally developed by Ouchterlony (1948) to evaluate the production of diphtheria toxin by clinical bacterial isolates, the method continues to be used regularly in identification of antibody responses in clinical infections (Herren et al 2016).…”

Answers to the Letters to the Editor of P. Lambert et al. and L. G. Czaplewski concerning “Prospective study using anterior approach did not show association between Modic 1 changes and low grade infection in lumbar spine” by Rigal J, Thelen T, Byrne F, Cogniet A, Boissière L, Aunoble S, Le Huec JC (Eur Spine J [2016]; 25(4):1000–5. doi:10.1007/s00586-016-4396-5)

“…In particular, a variety of culture incubation periods have been employed in studies described in the literature. We have applied an extended culture of 15 days, which is the optimum culture incubation period for the recovery of P. acnes [6].…”