Candidal Prosthetic Hip Infection in a Patient with Previous Candidal Sepsis - A Case Report.

A 60 year-old woman with hip dysplasia battled with duodenal cancer that was complicated with Candida tropicalis sepsis. Two years later, the patient underwent a total hip arthroplasty (THA). She complained of a persisting low-grade fever and local heat on the THA scar. Arthrocentesis of the hip was performed and the Candida tropicalis was detected. Debridement and polyethylene liner/modular head exchange were performed 28 days after the primary THA. Fluconazole was administrated for one year. The patient reported no symptoms five years later. It was found that periprosthetic infection could be prevented by implant preservation surgery.

Influence of retrieved hip- and knee-prosthesis biomaterials on microbial detection by sonication.

Microorganisms' ability to adhere and form a biofilm differs among biomaterials; however, clinical data are conflicting. Microbial adherence and biofilm formation on different biomaterials of explanted joint prosthesis components were investigated. Consecutive patients with explanted joint prosthesis were prospectively included. The bacterial load dislodged from retrieved prosthetic components was evaluated qualitatively and quantitatively in sonication-fluid cultures. For comparison between groups, one-way ANOVA and Wilcoxon signed-rank test were used. A total of 112 components originating from 58 knee and 54 hip prostheses were retrieved from 40 patients. Components were made of titanium alloy in 42 cases, cobalt-chromium alloy in 38 and polyethylene in 32. Bacteria in sonication-fluid cultures grew in all polyethylene components (100 %), followed by titanium alloy (79 %) and cobalt-chromium components (71 %). Larger bacterial counts were found on polyethylene than on titanium (p < 0.013) or cobalt-chromium alloy (p = 0.028). Coagulase-negative Staphylococcus aureus and Streptococcus species were most commonly isolated. In conclusion, polyethylene showed larger biofilm burden than metal alloys, indicating their higher microbial adhesion affinity in vivo. Sonication of polyethylene liners, rather than the whole prosthesis, was sufficient for diagnosis of prosthetic joint infection. Moreover, bacterial counts were larger after sonication of polyethylene liners than of metal alloys, suggesting intrinsic differences in the ability for biofilm formation on various biomaterials. Polyethylene liners allowed the diagnosis of prosthetic joint infections (PJIs) in all investigated cases, suggesting that sonication of polyethylene liners rather than of the complete prosthesis was sufficient for pathogen detection in PJIs.

Does the use of a closed-suction drain reduce the effectiveness of an antibiotic-loaded spacer in two-stage exchange Arthroplasty for Periprosthetic hip infection? A prospective, randomized, controlled study.

BACKGROUND: There is a concern regarding the use of a closed-suction drain (CSD) in two-stage exchange arthroplasty for periprosthetic joint infection as it may decrease the antibiotic concentrations in the joint fluids. The purpose of this study was to identify whether the use of a CSD could reduce local antibiotic concentrations following spacer implantation. METHODS: A prospective, randomized, controlled trial was conducted at our institution between January 2018 and November 2018. We enrolled 32 patients undergoing two-stage exchange arthroplasty for periprosthetic hip infection with an interim cement spacer containing 4-g vancomycin and 2-g meropenem per 40-g methyl-methacrylate cement polymer. Patients were randomized and evenly divided into the study group (non-CSD) and control group (CSD group) by sealed envelopes. Drainage samples of joint fluids (n = 160) were collected every 24 h for the first five days following spacer implantation. The antibiotic concentrations of drainage samples were measured by high-performance liquid chromatography, and the bioactivities of the drainage samples against methicillin-sensitive and methicillin-resistant Staphylococcus aureus (MSSA and MRSA) and E. coli were assessed. RESULTS: There was no significant difference in the decrease of vancomycin (study group vs. control group: 163.20 ± 77.05 vs. 162.39 ± 36.31; p = 0.917) and meropenem concentration (123.78 ± 21.04 vs. 117.27 ± 19.38; P = 0.548) between the two groups during the first five days following spacer implantation. All joint drainage samples in each group exhibited antibacterial activity against MSSA, MRSA and E. coli. CONCLUSIONS: The use of CSD following the implantation of an antibiotic-loaded cement spacer does not reduce the effectiveness of such a spacer in two-stage exchange arthroplasty. (Chinese Clinical Trial Registry, ChiCTR-INR-17014162. Registered 26 December 2017.).

Two-stage cementless hip revision for peri-prosthetic infection with an antibacterial hydrogel coating: results of a comparative series.

PURPOSE: The aim of this study was to investigate the hypothesis that a two-stage exchange procedure, performed with an antibiotic-loaded, fast-resorbable hydrogel coating, may provide better infection cure rate than a two-stage procedure without the coating, in patients affected by peri-prosthetic hip infection. METHODS: In this case-control study, 27 patients, treated with a two-stage procedure, using cementless implants coated with an antibiotic-loaded hydrogel (DAC®, "Defensive Antibacterial Coating"), were compared with 27 matched controls, treated with a two-stage cementless revision procedure, without the coating. RESULTS: At a mean follow-up of 2.7 (minimum 2.1-maximum 3.5) years, no evidence of infection, implant loosening, or adverse events were observed in the DAC-treated group, compared to four cases of infection recurrence in the control group. CONCLUSIONS: Although in a relatively limited series of patients our data show that cementless two-stage hip revision, performed with an antibacterial hydrogel coating, may provide better infection control than two-stage without the coating, with reduced hospitalization time, these findings warrant further studies in the possible applications of antibacterial coating technologies to treat implant-related infections.

Cementless One-Stage Revision in Chronic Periprosthetic Hip Joint Infection. Ninety-One Percent Infection Free Survival in 56 Patients at Minimum 2-Year Follow-Up.

BACKGROUND: Cementless 1-stage revision in chronic periprosthetic hip joint infections is limited evaluated. The purpose of this study was to evaluate a specific treatment protocol in this patient group. METHODS: The study was performed as a multicenter, proof-of-concept, observational study with prospective data collection. Patients were treated with a cementless 1-stage revision according to the CORIHA protocol between 2009 and 2014. Fifty-six patients, McPherson type III-A/B-1/2, were enrolled with a mean follow-up time from the CORIHA procedure of 4 years (minimum of 2 years). The primary outcome was re-revision performed due to infection and was evaluated by competing risk analysis, with death and aseptic revision as competing events. All-cause mortality was evaluated by Kaplan-Meier survival analysis. Oxford Hip Score (OHS) was used as disease-specific patient-reported outcome measure. RESULTS: The cumulative incidence of re-revision due to infection was 8.9% (confidence interval [CI] 3.2%-18.1%). The 1-year and 5-year survival incidence was 96% (CI 86%-99%) and 89% (CI 75%-95%). OHS at baseline was 19.9 (CI 17.3-22.6) and at 24-month follow-up 35.1 (CI 31.7-38.5). The mean change in OHS from baseline to 24-month follow-up was 11.8 points (CI 7.3; 16.3). Three patients had aseptic revision performed: two suffered periprosthetic fractures and one had stem subsidence. Failure analysis of the 5 reinfections did not detect a clear pattern as to the cause of failure. CONCLUSION: We found that cementless 1-stage revision in chronic periprosthetic hip joint infections has low reinfection rates in selected patients and may be applicable as a first-line treatment.

Sonication of antibiotic spacers predicts failure during two-stage revision for prosthetic knee and hip infections.

BACKGROUND: Periprosthetic joint infection is a leading cause of failure after two-stage reimplantation. One cause of relapse may be persistent subclinical infection. Difficulty exists in detecting biofilm-forming infections. Sonication disrupts biofilm and has led to higher rates of positive intraoperative cultures. QUESTIONS/PURPOSES: Our aims in this study were to determine (1) if sonication results were predictive of failure, including reinfection, at 2-year followup; and (2) whether sonication of antibiotic spacers at the time of reimplantation improves sensitivity of intraoperative cultures. METHODS: We prospectively followed 36 consecutive patients undergoing two-stage reimplantation for periprosthetic hip or knee infection. Minimum followup was 19 months (mean, 29.9 months; range, 19­38 months). Results of intraoperative cultures and sonicated antibiotic spacers were analyzed. RESULTS: Positive sonication results were predictive of failure as defined by reinfection at 2-year followup. Among the 18 patients who had positive sonication results, reinfection developed in nine patients (50%) compared with two of 18 patients (11%) with negative sonication results (odds ratio, 8.0; 95% CI, 1.2­69.0). Sonication of antibiotic spacers improved the sensitivity of intraoperative cultures from 45% to 82%. [corrected]. CONCLUSIONS: Sonication of antibiotic spacers appears to be useful in predicting failure attributable to recurrent infection after two-stage reimplantation. For patients with positive sonication cultures during reimplantation, more aggressive antimicrobial treatment may be indicated after reimplantation. LEVEL OF EVIDENCE: Level III, diagnostic study. See the Instructions for Authors for a complete description of levels of evidence.

Successful clinical use of daptomycin-impregnated bone cement in two-stage revision hip surgery for prosthetic joint infection.

OBJECTIVE: To describe the safe and successful use of daptomycin-impregnated polymethyl methacrylate (PMMA) bone cement in the treatment of a case of recurrent prosthetic joint infection in a patient with multiple antibiotic allergies and past colonization with multiply antibiotic-resistant organisms. CASE SUMMARY: A 79-year-old female had a history of chronic recurrent left prosthetic hip infection. The patient had confirmed allergies to multiple antibiotics and a past history of colonization with methicillin-resistant Staphylococcus aureus. At first-stage revision surgery, the infected prosthesis was removed and samples were sent for microbiologic culture. A spacer device was fashioned, with incorporation of daptomycin and gentamicin into the PMMA bone cement at a concentration of 5% w/w for each antibiotic. Systemic daptomycin and gentamicin were administered postoperatively for 14 days. Propionibacterium acnes was isolated from deep-tissue specimens. The patient made excellent postoperative progress and was discharged after 2 weeks. Second-stage revision surgery was performed at 6 months, with no signs of persistent infection. She remained well, pain free, and mobilizing independently 2 years later. DISCUSSION: Daptomycin, a cyclic lipopeptide antibiotic, is approved for systemic treatment of endocarditis and skin and soft tissue infections. In vitro data demonstrate acceptable drug elution from and tensile strength of daptomycin-impregnated PMMA bone cement; however, clinical data are lacking. In our patient's case, the cement formulation was well tolerated, with no adverse effects detected, and demonstrated adequate mechanical strength in vivo. Infection with P. acnes, an unusual pathogen, was successfully treated. Further clinical studies are required to assess the efficacy of daptomycin-impregnated cement in infection with more typical pathogens, such as S. aureus. CONCLUSIONS: Daptomycin impregnation of PMMA bone cement may be an option in cases in which patient or pathogen factors preclude use of routinely incorporated agents.

Successful treatment of Candida albicans-infected total hip prosthesis with staged procedure using an antifungal-loaded cement spacer.

We present a rare case of an immunocompetent host who developed a Candida albicans-infected total hip prosthesis. The infection could not be eradicated with debridement and extensive antifungal therapy. Our patient first underwent a resection of the proximal femur and local treatment with gentamicin-loaded cement beads. In a second procedure, a handmade cement spacer impregnated with voriconazole, amphotericin B, and vancomycin was placed. After 3 months of additional systemic antibiotic therapy, the patient remained afebrile, and a tumor prosthesis was placed. Six years postoperatively, she is doing well, walking with a small limp and no signs of recurrent infection. This is the first report on elution of voriconazole and amphotericin B from bone cement delivered at clinically significant concentrations for at least 72 hours.

Comparison of one-stage revision with antibiotic cement versus two-stage revision results for infected total hip arthroplasty.

Eighty three patients of infected total hip arthroplasty (THA) treated by implant removal and staged revision were retrospectively analyzed. Clinical characteristics and treatment outcomes were compared between three groups: 17 one-stage revisions (one-stage group), 44 two-stage revisions with second stage reimplantation (two-stage reimplanted group), and 22 planned two-stage but no reimplantation (two-stage non-reimplanted group). The rate of infection control was 82% (14/17) in the one-stage group, 75% (33/44) in the two-stage reimplanted group, and 68% (15/22) in the two-stage non-reimplanted group (P=0.60). The mean of latest Harris hip score was 77, 60, and 58 (P=0.14), and the UCLA activity score was 4.0, 4.2, and 3.6 (P=0.74) for each group, respectively. Results of this study suggest that one-stage revision arthroplasty can be a treatment option in selected cases of infected THA with a satisfactory infection control rate and functional outcomes comparable to those of two-stage revision.

Characterisation of in vivo release of gentamicin from polymethyl methacrylate cement using a novel method.

PURPOSE: The purpose of this study was to investigate the in vivo elution kinetics of gentamicin from bone cement by assessing antibiotic levels in the urine. METHODS: Urinary samples of 35 patients who had undergone primary total hip arthroplasty were collected post-operatively. Gentamicin concentrations were analysed using the fluorescence polarisation immunoassay technique. RESULTS: The mean duration of urinary gentamicin release in all cases was 43 days (range 13-95). There was still detectable gentamicin at the final collection in 20% (7/35) of cases, and in these cases, the mean gentamicin release was 71 days. CONCLUSIONS: From the assessment of urinary gentamicin, we were able to demonstrate the biphasic gentamicin elution from bone cement. In addition, there were detectable concentrations of the antibiotic from the urinary samples for prolonged periods of up to two to six months. Our study indicates that the assessment of urinary antibiotics can offer a non-invasive method of monitoring the in vivo release kinetics of antibiotics from bone cement.

Good results in postoperative and hematogenous deep infections of 89 stable total hip and knee replacements with retention of prosthesis and local antibiotics.

BACKGROUND: Deep postoperative and hematogenous prosthesis infections may be treated with retention of the prosthesis, if the prosthesis is stable. How long the infection may be present to preclude a good result is unclear. PATIENTS AND METHODS: We retrospectively studied 89 deep-infected stable prostheses from 69 total hip replacements and 20 total knee replacements. There were 83 early or delayed postoperative infections and 6 hematogenous. In the postoperative infections, treatment had started 12 days to 2 years after implantation. In the hematogenous infections, symptoms had been present for 6 to 9 days. The patients had been treated with debridement, prosthesis retention, systemic antibiotics, and local antibiotics: gentamicin-PMMA beads or gentamicin collagen fleeces. The minimum follow-up time was 1.5 years. We investigated how the result of the treatment had been influenced by the length of the period the infection was present, and by other variables such as host characteristics, infection stage, and type of bacteria. RESULTS: In postoperative infections, the risk of failure increased with a longer postoperative interval: from 0.2 (95% CI: 0.1-0.3) if the treatment had started ≥ 4 weeks postoperatively to 0.5 (CI: 0.2-0.8) if it had started at ≥ 8 weeks. The relative risk for success was 0.6 (CI: 0.3-0.95) if the treatment had started ≥ 8 weeks. In the hematogenous group, 5 of 6 infections had been treated successfully. INTERPRETATION: A longer delay before the start of the treatment caused an increased failure rate, but this must be weighed against the advantage of keeping the prosthesis. We consider a failure rate of < 50% to be acceptable, and we therefore advocate keeping the prosthesis for up to 8 weeks postoperatively, and in hematogenous infections with a short duration of symptoms.

Fungal periprosthetic hip and knee joint infections clinical experience with a 2-stage treatment protocol.

Fungal periprosthetic joint infections are a rare entity in orthopedic surgery, and there exist no guidelines according to which these infections can be successfully managed. Between 2004 and 2009, 7 patients with fungal periprosthetic joint infections (4 total hip arthroplasties and 3 total knee arthroplasties) have been treated with a 2-stage protocol and implantation of antibiotic-loaded cement spacers. Most of the infection was caused by Candida species. Systemic antifungal agents were administered for 6 weeks in 6 cases and 6 months in 1 case. The mean spacer implantation time was 12 weeks. At a mean follow-up of 28 months (5-70 months), no persistence of infection or reinfection could be observed. A 2-stage treatment protocol with implantation of an antibiotic-loaded cement spacer is an efficient option in the treatment of fungal periprosthetic infections.

The preoperative prediction of success following irrigation and debridement with polyethylene exchange for hip and knee prosthetic joint infections.

Although the criterion standard for the treatment of prosthetic joint infections (PJIs) is 2-stage revision with interim placement of an antibiotic-loaded spacer, irrigation and debridement with polyethylene exchange offer advantages such as fewer surgeries, reduced potential for intraoperative complications, and lower direct costs. The purpose of this study was to develop a tool to preoperatively predict the probability of successful infection eradication following irrigation and debridement with polyethylene exchange for hip or knee PJIs. A total of 10,411 surgical cases were retrospectively reviewed, and data were collected from 309 charts. Overall, 149 (48.2%) cases failed to eradicate the infection following irrigation and debridement with polyethylene exchange. Univariate analysis identified multiple variables independently associated with reinfection including duration of symptoms, preoperative inflammatory markers, and infecting organism. Logistic regression was used to generate a model (bootstrap-corrected concordance index of 0.645) to predict successful eradication of the infection, which was the basis for a nomogram. Using commonly obtained preoperative variables, the nomogram can be used to predict the probability of infection-free survival at 1, 2, 3, 4, and 5 years. Preoperative knowledge of the probability that a treatment strategy will eradicate a patient's PJI may improve risk assessment.

Identification of oral bacterial DNA in synovial fluid of patients with arthritis with native and failed prosthetic joints.

OBJECTIVE: We examined the presence of bacterial DNA in synovial fluids of native or clinically aseptically failed prosthetic joints from patients having periodontal disease and arthritis to determine whether there is bacterial spread from the oral cavity to the joints. METHODS: A total of 36 subjects were enrolled in the study. Among these, 11 were diagnosed with rheumatoid arthritis (RA) and 25 were diagnosed with osteoarthritis (OA). Eight patients with OA and 1 patient with RA had failed prostheses. Synovial fluid was aspirated from the affected hip or knee joint. Pooled subgingival plaque samples were collected, followed by clinical periodontal examination. Bacterial DNA was extracted from the collected synovial fluid and dental plaque samples were followed by polymerase chain reactions and DNA sequence analysis of the 16S-23S rRNA genes. RESULTS: Of the 36 patients, bacterial DNA was detected in the synovial fluid samples from 5 patients (13.9%): 2 with RA (1 native and 1 failed prosthetic joints) and 3 with OA (1 native and 2 failed prosthetic joints). Of these 5 patients, 2 were diagnosed with periodontitis and had identical bacterial clones (Fusobacterium nucleatum and Serratia proteamaculans, respectively) detected in both the synovial fluid and the dental plaque samples. Fusobacterium nucleatum was the most prevalent, detected in 4 of the 5 positive samples. No cultures were done and no patients were treated with antibiotics or developed clinical infection. CONCLUSIONS: The present findings of bacterial DNA in the synovial fluid suggest the possibility of organisms translocating from the periodontal tissue to the synovium. We suggest that patients with arthritis or failed prosthetic joints be examined for the presence of periodontal diseases and be treated accordingly.

Two-stage exchange for infected resurfacing arthroplasty: use of a novel cement spacer technique.

Infection after total hip arthroplasty is a devastating complication. A 2-stage reimplantation with antibiotic-impregnated interval spacer is typically recommended. We present a case of infected resurfacing hip arthroplasty treated with a novel cement spacer technique. The aim was to avoid the introduction of the infection into the femoral medullary canal with the use of a conventional stemmed antibiotic cement spacer. Reimplantation was accomplished routinely, and the patient remains infection-free at 9 months.

Acyclic acetabular roof reconstruction for severe superior segmental acetabular bone loss in 2-stage surgery for infected hip arthroplasty.

Ensuring the stability of a cemented PROSTALAC cup (Depuy, Warsaw, Ind) in the presence of severe superior acetabular segmental deficiency is critical to the success of the first-stage surgery. We present an illustrative case and the surgical technique required to achieve this.

A two-stage retention débridement protocol for acute periprosthetic joint infections.

BACKGROUND: Due to the historically poor infection control rates with débridement and component retention for acute periprosthetic infections we developed a new approach for treating acute periprosthetic total joint infections: initial débridement with prosthesis retention and placement of antibiotic-impregnated cement beads followed by a second débridement within 7 days, at which time the beads are removed and new modular parts inserted. Intravenous antibiotics were used for 6 weeks followed by oral antibiotics. Depending on the clinical situation, antibiotics are discontinued or in selected patients continued indefinitely. QUESTIONS/PURPOSES: We determined the ability of this two-stage débridement to control infection. METHODS: We retrospectively reviewed the charts of 20 patients who underwent this technique; 2 had postoperative and 18 had hematogenous infections. The primary outcome measure was the infection control. The minimum followup was 1 year (mean, 3.5 years; range, 1.2-7.5 years). RESULTS: Two of the 20 patients had persistent infection. There were no failures in the acute postoperative group (0 of 2) and two of 18 in the acute hematogenous group. Of the 18 patients without evidence of persistent infection, 10 were no longer on antibiotics at the most recent followup and eight were treated with long-term antibiotics due to compromised host status. CONCLUSIONS: The control of infection in 18 of 20 patients using this technique compares favorably with historical success rates, which range from 24% to 100%. Further research is required to analyze the individual contribution of débridement technique, the use of serial débridements, local depot antibiotics, and combination antibiotic therapy on short-term infection control rates and the long-term persistent control of periprosthetic infection. LEVEL OF EVIDENCE: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of level of evidence.

Two-stage reconstruction of infected hip joints.

Two-stage reconstruction using an antibiotic-loaded cement spacer is the preferred treatment of deep infection after total hip arthroplasty (THA). We evaluated the results of this technique for the treatment of primary hip infections. Nine consecutive patients with infected hip joints were treated using this technique. The average duration of follow-up was 42 months. Debridement and insertion of an antibiotic-loaded cement spacer was performed in the first stage. After eradication of infection, it was converted to THA in the second stage. Of the 9 hips, 8 were successfully converted to THA after an average of 23 weeks. One patient required spacer reinsertion, and another experienced reinfection after THA. Average Harris hip score improved from 38.37 before surgery to 57.62 between the 2 stages to 97.83 at final follow-up. Two-stage reconstruction using an antibiotic-loaded cement spacer was found to give satisfactory results for the treatment of hip infections with various etiologies.

Incorporation of large amounts of gentamicin sulphate into acrylic bone cement: effect on handling and mechanical properties, antibiotic release, and biofilm formation.

Bacterial infection remains a significant complication following total joint replacement. If infection is suspected when revision surgery is being performed, a large dose of antibiotic, usually gentamicin sulphate, is often blended with the acrylic bone cement powder in an attempt to reduce the risk of recurrent infection. In this in-vitro study the effect of small and large doses of gentamicin sulphate on the handling and mechanical properties of the cement, gentamicin release from the cement, and in-vitro biofilm formation by clinical Staphylococcus spp. isolates on the cement was determined. An increase in gentamicin loading of 1, 2, 3, or 4 g, in a cement powder mass of 40 g, resulted in a significant decrease in the compressive and four-point bending strength, but a significant increase in the amount of gentamicin released over a 72h period. When overt infection was modelled, using Staphylococcus spp. clinical isolates at an inoculum of 1 x 10(7) colony-forming units/ml, an increase in the amount of gentamicin (1, 2, 3, or 4 g) added to 40 g of poly(methyl methacrylate) cement resulted in an initial decrease in bacterial colonization but this beneficial effect was no longer apparent by 72 h, with the bacterial strains forming biofilms on the cements despite the release of high levels of gentamicin. The findings suggest that orthopaedic surgeons should carefully consider the clinical consequences of blending large doses (1 g or more per 40 g of poly(methyl methacrylate)) of gentamicin into Palacos R bone cement for use in revision surgery as the increased gentamicin loading does not prevent bacterial biofilm formation and the effect on the mechanical properties could be important to the longevity of the prosthetic joint.

Analysis of postoperative and hematogenous prosthetic joint-infection microbiological patterns in a large cohort.

OBJECTIVES: This study was undertaken to analyze prosthetic joint infection (PJI)-causing microorganisms and compare their distribution patterns according to PJI classification. METHODS: Cohort study from a single referral center for bone-and-joint infections from January 2004 to December 2015. RESULTS: Nine hundred and twenty-six patients, who developed 997 PJIs, involving the hip (62%), knee (35%) and/or shoulder (1%), were included. PJIs were classified as early postoperative (19%), late chronic (30%), hematogenous (35%) and undetermined (16%). Pathogens most frequently isolated from early-postoperative PJIs were staphylococci (57%), with 25% each Staphylococcus aureus or Staphylococcus epidermidis; 21% were polymicrobial and 10% Gram-negative rods. For late-chronic PJIs, the most frequent microbes were staphylococci (61%), predominantly S. epidermidis (35%); anaerobic bacteria were isolated from 15%; 11% were polymicrobial. Hematogenous PJIs were 99% monomicrobial. Although S. aureus was the most frequently isolated species (28%), streptococci were isolated slightly more often than staphylococci (39% vs. 36%). Among streptococci, group B streptococci were the most frequent (15%). The portal of entry was identified for 52% of hematogenous PJIs: 15% cutaneous, 11% dental, 9% gastrointestinal, 6% urinary, and 11% miscellaneous. CONCLUSION: Although a wide variety of microorganisms was isolated from PJIs, specific microbiological patterns were observed according to infection classification.