Infectious arthritis caused by Propionibacterium acnes: a report of two cases

Bilateral native knee septic arthritis due to Propionibacterium acnes; a case report and review of literature

Propionibacterium acnes should be considered in any case of indolent septic arthritis. Cultures should be followed for 2 weeks as our cultures were negative for 7 days before growing P. acnes. Irrigation and debridement followed by antibiotics is the standard of care.

Cutibacteriumacnes Septic Arthritis of the Nonoperated Knee: A Case Report

Cutibacterium (Propionibacterium) acnes , a gram-positive bacillus with low pathogenicity, is an uncommon but known cause of prosthetic joint infections, particularly related to shoulder surgery. C. acnes , however, is an extremely rare pathogen in the nonoperated knee joint. This report details an uncommon case of C. acnes septic knee arthritis after multiple intra-articular steroid injections in a 56-year-old male patient. After an indolent presentation and late diagnosis, the patient underwent surgical debridement with IV antibiotic management. This case illustrates that intra-articular corticosteroid injections for the management of osteoarthritis are not without risk. Literature supporting their use remains limited and clinicians should use proficient clinical judgment for appropriate patient selection for these injections. Vigilance following injections or aspirations of the knee should be maintained to identify the indolent clinical presentation of C. acnes septic arthritis.

De novo Propionibacterium acnes septic arthritis

We report the third identifiable case of septic arthritis due to Propionibacterium acnes arising in the absence of prior surgical intervention. This anaerobic Gram-positive bacillus is now recognised as an important cause of postoperative infections, typically presenting in an indolent fashion some months after surgery. Reports of de novo septic arthritis due to P. acnes are exceedingly rare. Our case adds to the literature and significantly broadens the reported pathogenic potential of the organism, which in this instance has caused rapid and serious joint destruction.

Rheumatoid arthritis-associated RBPJ polymorphism alters memory CD4+ T cells

Notch signaling has recently emerged as an important regulator of immune responses in autoimmune diseases. The recombination signal-binding protein for immunoglobulin kappa J region (RBPJ) is a transcriptional repressor, but converts into a transcriptional activator upon activation of the canonical Notch pathway. Genome-wide association studies of rheumatoid arthritis (RA) identified a susceptibility locus, rs874040(CC), which implicated the RBPJ gene. Here, chromatin state mapping generated using the chromHMM algorithm reveals strong enhancer regions containing DNase I hypersensitive sites overlapping the rs874040 linkage disequilibrium block in human memory, but not in naïve CD4(+) T cells. The rs874040 overlapping this chromatin state was associated with increased RBPJ expression in stimulated memory CD4(+) T cells from healthy subjects homozygous for the risk allele (CC) compared with memory CD4(+) T cells bearing the protective allele (GG). Transcriptomic analysis of rs874040(CC) memory T cells showed a repression of canonical Notch target genes IL (interleukin)-9, IL-17 and interferon (IFN)γ in the basal state. Interestingly, activation of the Notch pathway using soluble Notch ligand, Jagged2-Fc, induced IL-9 and IL-17A while delta-like 4Fc, another Notch ligand, induced higher IFNγ expression in the rs874040(CC) memory CD4(+) T cells compared with their rs874040(GG) counterparts. In RA, RBPJ expression is elevated in memory T cells from RA patients compared with control subjects, and this was associated with induced inflammatory cytokines IL-9, IL-17A and IFNγ in response to Notch ligation in vitro. These findings demonstrate that the rs874040(CC) allele skews memory T cells toward a pro-inflammatory phenotype involving Notch signaling, thus increasing the susceptibility to develop RA.

Presence of Propionibacterium acnes in primary shoulder arthroscopy: results of aspiration and tissue cultures

BACKGROUND

Infection after shoulder surgery has a serious impact on patient outcome and costs associated with care. Propionibacterium acnes infection may be insidious and manifest years after index surgery with resultant joint arthropathy or prosthesis infection. Our goal was to evaluate the presence of P. acnes in a group of patients undergoing primary arthroscopic shoulder surgery to better understand this organism.

METHODS

Samples were collected from 57 patients undergoing first-time shoulder arthroscopy. Demographic data and medical comorbidities were collected. A control, 2 skin swabs, synovial fluid, and 3 tissue samples were obtained. All samples were placed on aerobic plates, on anaerobic plates, and in thioglycolate broth and held for 28 days.

RESULTS

Fifty-seven patients underwent arthroscopic shoulder surgery. The mean age was 51 years. Eighty-one samples (21.8%) were positive for P. acnes when cultures were held 14 days; 32 subjects (56%) had at least 1 culture that grew P. acnes. Positive skin cultures for P. acnes increased from 15.8% before incision to 40.4% at closure. This was even more pronounced in men as positive skin cultures increased from 31.3% before incision to 63.0% at closure. Thirteen patients (22.8%) had more than 3 cultures positive. None of the patients in this study have had signs or symptoms to suggest clinical P. acnes infection.

CONCLUSIONS

Of all subjects studied, 56% had at least 1 positive culture; 21% (of all 371 culture specimens obtained) grew P. acnes. We suspect that it is a consequence of true positive cultures from imperfect skin preparation and dermal contamination.

Management of Propionibacterium acnes infection after shoulder surgery

Propionibacterium acnes (P. acnes) is a gram-positive anaerobic bacillus commonly isolated from the flora of the face, chest, and axilla region. It has emerged as a major pathogen responsible for postoperative shoulder infections after both arthroscopy and arthroplasty procedures. Patients with P. acnes shoulder infection typically present with normal laboratory values (white blood cells (WBC), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP)) making diagnosis difficult. Several intraoperative tissue cultures should be obtained and cultured in both agar plate and broth in aerobic and anaerobic conditions for a minimum of 13 days to optimize the sensitivity and specificity to detect P. acnes. The utilization of intraoperative frozen sections to detect P. acnes infection is not reliable. Risk factors include male, cloudy synovial fluid, lucencies around the implant, and periprosthetic membrane formation. Managements include irrigation and debridement, single or two-staged revision, and intravenous antibiotics. Open biopsy prior to the final implantation (two-staged revision) may help detect persistent P. acnes infection. Penicillin and cephalosporins are effective against clinical P. acnes infection and biofilm in vitro. Combination antibiotic therapy with rifampin and daptomycin may further increase the clinical efficacy of treatment.

Complications of shoulder arthroscopy

Over the past 20 to 30 years, arthroscopic shoulder techniques have become increasingly popular. Although these techniques have several advantages over open surgery, surgical complications are no less prevalent or devastating than those associated with open techniques. Some of the complications associated with arthroscopic shoulder surgery include recurrent instability, soft-tissue injury, and neurapraxia. These complications can be minimized with thoughtful consideration of the surgical indications, careful patient selection and positioning, and a thorough knowledge of the shoulder anatomy. Deep infection following arthroscopic shoulder surgery is rare; however, the shoulder is particularly susceptible to Propionibacterium acnes infection, which is mildly virulent and has a benign presentation. The surgeon must maintain a high index of suspicion for this infection. Thromboemoblic complications associated with arthroscopic shoulder techniques are also rare, and studies have shown that pharmacologic prophylaxis has minimal efficacy in preventing these complications. Because high-quality studies on the subject are lacking, minimal evidence is available to suggest strategies for prevention.

Propionibacterium acnes: an underestimated etiology in the pathogenesis of osteoarthritis?

BACKGROUND

Propionibacterium acnes is a common pathogen in infections after shoulder surgery. Recent reports found positive P acnes cultures in a high percentage of patients who had revision shoulder arthroplasty for "aseptic loosening" without any overt signs of infection. Isolation of P acnes is difficult, and by use of conventional microbiological protocols of 48-hour incubation, a considerable proportion of patients with possible P acnes infection may remain unidentified. We recently noted P acnes in shoulder joint cultures in patients undergoing primary shoulder replacement for glenohumeral arthropathy without any signs of infection.

METHODS

We collected aspirates and biopsy specimens from 55 consecutive patients with arthritic shoulders undergoing primary joint replacement and examined them for the presence of P acnes. Special measures were taken to ensure that the specimens were carefully taken from within the joint to reduce the risk of contamination to minimal.

RESULTS

In 23 of 55 consecutive patients (41.8%) undergoing primary shoulder joint replacement, P acnes was found in the joint fluid and tissues taken before the insertion of the implants. All these patients were treated early postoperatively with pathogen-directed specific dual oral antibiotic treatment for 4 weeks. In none have any signs of infection developed.

DISCUSSION AND CONCLUSION

This finding of a high incidence of P acnes in joints before arthroplasty may suggest a role of P acnes in the pathogenesis of glenohumeral arthropathy. In addition, it raises the question of whether development of painful joint replacement later on and presumed aseptic loosening do, in fact, comprise an unrecognized low-grade infection that has been present since before the index operation.

Propionibacterium acnes infection as an occult cause of postoperative shoulder pain: a case series

BACKGROUND

Infections after shoulder surgery are potentially devastating complications. Propionibacterium acnes is recognized as a causal agent in shoulder infections. The clinical presentation is usually insidious and nonspecific, but a P. acnes infection could be an occult cause of postoperative shoulder pain.

QUESTIONS/PURPOSES

What are the clinical and microbiologic characteristics of a postsurgical P. acnes shoulder infection and how should it be addressed?

PATIENTS AND METHODS

Ten patients with an average age of 57 years presented with P. acnes postsurgical shoulder infection. Clinical infection signs and surgical history were assessed and joint aspirates and tissue biopsy specimens were obtained. Diagnosis was confirmed by microbiologic cultures.

RESULTS

At the time of confirmation of the diagnosis, clinical signs of infection were absent. C-reactive protein and erythrocyte sedimentation rates were inconsistently elevated. Cultures took a mean 7 days to confirm organism growth. The average time from surgery to diagnosis of infection was 1.8 years (range, 0.07-8.0 years). All patients underwent irrigation and débridement and were treated with antibiotics for 6 weeks.

CONCLUSIONS

P. acnes shoulder infections should be considered as a cause for persistent, unexplained shoulder pain. Shoulder aspirations and tissue samples should be obtained. Surgical débridement and intravenous antibiotics are necessary treatment modalities.

LEVEL OF EVIDENCE

Level IV, Prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Microbiology and management of joint and bone infections due to anaerobic bacteria

PURPOSE

To describes the microbiology, diagnosis, and management of septic arthritis and osteomyelitis due to anaerobic bacteria.

RESULTS

The predominant anaerobes in arthritis are anaerobic Gram-negative bacilli (AGNB) including the Bacteroides fragilis group, Fusobacterium spp., Peptostreptococcus spp., and Propionibacterium acnes. Infection with P. acnes is associated with a prosthetic joint, previous surgery, and trauma. B. fragilis group is associated with distant infection, Clostridium spp. with trauma, and Fusobacterium spp. with oropharyngeal infection. Most cases of anaerobic arthritis, in contrast to anaerobic osteomyelitis, involved a single isolate, and most cases are secondary to hematogenous spread. The predominant anaerobes in osteomyelitis are Bacteroides, Peptostreptococcus, Fusobacterium, and Clostridium spp. as well as P. acnes. Conditions predisposing to bone infections are vascular disease, bites, contiguous infection, peripheral neuropathy, hematogenous spread, and trauma. Pigmented Prevotella and Porphyromonas spp. are mostly isolated in skull and bite infections, members of the B. fragilis group in hand and feet infections, and Fusobacterium spp. in skull, bite, and hematogenous long bone infections. Many patients with osteomyelitis due to anaerobic bacteria have evidence of an anaerobic infection elsewhere in the body that is the source of the organisms involved in the osteomyelitis. Treatment of arthritis and osteomyelitis involving anaerobic bacteria includes symptomatic therapy, immobilization in some cases, adequate drainage of purulent material, and antibiotic therapy effective against these organisms.

CONCLUSIONS

Anaerobic bacteria can cause septic arthritis and osteomyelitis. Correct diagnosis and appropriate therapy are important contributor to successful outcome.

Propionibacterium acnes: An agent of prosthetic joint infection and colonization

BACKGROUND

Prosthetic joint infection (PJI) can present a diagnostic challenge, especially with slow-growing and poorly virulent bacteria.

OBJECTIVE

To describe the epidemiological, clinical and biological characteristics of Propionibacterium acnes PJI, their treatments and outcomes and compare 2 clinical pictures (according to the time PJI symptoms appeared after the index operation: < or = 2 years, > 2 years).

METHODS

We conducted a cohort study on P. acnes PJI. Diagnosis was based on > or = 2 positive cultures of intraoperative specimens taken during revision arthroplasties for infection or presumed aseptic loosening.

RESULTS

Fifty patients with prosthetic hip (34), knee (10) or shoulder (6) infections were included and analyzed according to their symptom-free interval: < or = 2 years for 35 and > 2 years for 15 (mean interval: 11+/-6 years). The numbers of previous prostheses (p=0.04) were higher for the shorter-interval group, which had more frequent signs of infection (p=0.004). These findings suggest infection in most of the patients whose PJI symptoms appeared: < or = 2 years after the index operation, and colonization in the majority of those whose symptoms appeared > 2 years after index surgery. Treatment combining exchange arthroplasty with prolonged intravenous antibiotics was successful for 92% of the patients.

CONCLUSION

P. acnes can cause different types of PJI: late chronic infections, colonization of loosened prostheses and, exceptionally, acute postoperative infections.

SAPHO: syndrome or concept? Imaging findings

The SAPHO syndrome was a term coined to include a variety of musculoskeletal disorders associated with skin conditions, mainly palmoplantar pustulosis and acne conglobata. It is more correctly a spectrum which includes the following: skin lesions, osteoarticular manifestations of synovitis hyperostosis and osteitis affecting particular target sites, and.a clinical course marked by relapses and remissions. The major sites of involvement are the anterior chest wall, the spine, long bones, flat bones, and large and small joints. The distribution and severity of involvement varies from the adult to the pediatric form of chronic recurrent multifocal osteomyelitis (CRMO). The diagnosis of SAPHO syndrome is not difficult when the typical osteoarticular lesions are located in characteristic target sites. The diagnosis is more difficult if atypical sites are involved and there is no skin disease.

Chronic destructive oligoarthritis associated with Propionibacterium acnes in a female patient with acne vulgaris: septic-reactive arthritis?

Propionibacterium acnes is an anaerobic bacillus implicated in certain chronic arthritides. This report describes an HLA-B27+ 17-year-old woman with acne vulgaris who presented with rapidly destructive arthritis in the left shoulder as well as an evolving left subclavicular adenopathy. One year later, arthritis was detected in the left knee; the inflammatory synovial fluid was sterile. Growth of P acnes was observed in cultures of the shoulder synovium and lymph nodes, but polymerase chain reaction was negative for Borrelia, Chlamydia, and Ureaplasma DNA. Three months of treatment with amoxicillin and rifampicin led to clinical disappearance of the oligoarthritis, but arthritis recurred in the left knee after discontinuation of therapy. On biopsy, bacteria were undetectable in the knee synovium, but chronic arthritis was evident histologically. Antibiotics were reintroduced for 12 months and were again effective against the clinical symptoms. Although the asymmetry, histologic features, arthritis-acne association, and genetic predisposition of this chronic destructive oligoarthritis would seem to indicate a reactive arthropathy, the isolation of P acnes from 2 distinct specimens prompted us to propose calling this a case of septic-reactive arthritis, which is further supported by the absence of progression after antibiotic therapy and the persistence of the rheumatism. To our knowledge, this is the first demonstration of the efficacy of prolonged antibiotic therapy on the joint manifestations of chronic rheumatism associated with acne.

[Infectious osteoarthritis due to Propionibacterium acnes. Two new cases]

INTRODUCTION

Propionibacterium acnes is an anaerobic germ, usually found as a saprophyte of the skin and the mucosa. It may be responsible for iatrogenic or spontaneous osteoarhritis.

EXEGESIS

We report two new cases of septic arthritis induced by P. acnes: a case of iatrogenic spondylodiscitis and a case of spontaneous septic arthritis of the lumbar facet joints. The two patients were immunocompetent, without acne.

CONCLUSION

Except for patients with criteria of the SAPHO syndrome (synovitis-acne-pustulosis-hyperostosis-osteomyelitis), osteoarthritis caused by P. acnes is increasingly described. The number of these infections is probably underestimated because of the technical problems involved in isolating P. acnes in the laboratory.