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Background: The cystic fibrosis (CF) pathogen, Mycobacterium abscessus complex, covers three subspecies: M. abscessus, M. massiliense, and M. bolletii. There are no clinical outcome data concerning M. bolletii. Our aim was to characterize M. bolletii lung infections in patients with CF.Methods: We included patients with M. bolletii lung infection recorded between 1994 and 2012 in France. Data were collected from the CF registry, medical records, and questionnaires submitted to the CF primary physician. Strains were typed by multilocus sequence typing analysis.Results: Fifteen cases were identified in nine CF centers. Nine patients (60%) presented with nontuberculous mycobacterial pulmonary disease. Follow-up of 13 patients showed a trend to more rapid decline in FEV1 in the first year of colonization (-9.4%; SD 19.3) in comparison with noninfected control subjects (-2.3%; SD 12.1) (P = .16). Twelve patients were treated, and 11 received oral macrolides. Treatment-induced eradication occurred in five patients (41.7%). Four patients died (26.7%), including one patient with fatal nontuberculous mycobacterial pulmonary disease. Inducible macrolide resistance was demonstrated in all strains. Patients always harbored unique strains.Conclusions: Our study reports the largest study cohort of CF patients infected with M. bolletii. M. bolletii infection affects both children and young adults, is most often symptomatic, and may be fatal. Macrolide-based therapies have poor effectiveness. There is no evidence of patient-to-patient transmission. [ABSTRACT FROM AUTHOR]

Objective: Tuberculous prosthetic joint infection (PJI) is uncommon and often diagnosed late. The objective here is to describe the management of tuberculous PJI at an osteoarticular infection referral center.Methods: A single-center retrospective study of patients managed between 1987 and 2016 was performed.Results: We identified 9 patients with a median age of 80 years. The hip was involved in all 9 patients. A known history of tuberculosis was noted in 2 patients and tuberculosis was present at other sites in 4 patients (lung, n = 3; urinary tract and scrotum, n = 1; and spine, n = 1). The diagnosis was established by routine intra-operative microbiological sampling, during (n = 4) or at a distance from (n = 5) hip arthroplasty. In the 8 patients with available follow-up data, mean antibiotic therapy duration was 16 months (range, 12-18 months). None of the 4 patients in whom the infection was diagnosed during arthroplasty required surgical revision because of the infection. Of the other 5 patients, 3 were managed by exchange arthroplasty and 1 by excision of the hip without subsequent prosthesis implantation; the remaining patient did not undergo revision surgery. The infection was eradicated in all 9 patients, after 15 months to 10 years.Conclusion: Tuberculous PJI is uncommon. The prognosis is good with prolonged antibiotic therapy, although the optimal duration remains unclear. The surgical strategy should be discussed on a case-by-case basis. The prosthesis can be retained if the tuberculous infection is an unexpected finding during arthroplasty. [ABSTRACT FROM AUTHOR]

Background: Preoperative synovial fluid culture is pivotal in the early diagnosis of prosthetic joint infection (PJI) but may yield false-positive and false-negative results. We evaluated the predictive value of synovial fluid culture results combined with the measurement of serum anti-staphylococcal antibodies (SASA)., Questions/purposes: (1) For hip and knee PJI, does combining positive SASA results with preoperative synovial culture results improve the positive predictive value (PPV) of preoperative synovial fluid culture alone? (2) Does combining preoperative synovial fluid culture results with a positive cell count and differential result increase the PPV of preoperative synovial fluid culture alone? (3) What proportion of isolated organisms exhibit concordance in antibiotic susceptibility: preoperative aspiration versus intraoperative isolates?, Methods: A prospective study was conducted at two French reference centers that manage bone and joint infections and included 481 adult patients who had a revision or resection arthroplasty between June 25, 2012 and June 23, 2014. Exclusion criteria including no serum sample available for immunoassay, the lack of microbiological documentation, and the absence of preoperative aspiration reduced the patient number to 353. Seven patients with an undetermined SASA result were excluded from the analysis. We also excluded patients with PJI involving more than one Staphylococcus species (polystaphylococcal infection) and those in whom more than one Staphylococcus species was recovered from the preoperative synovial fluid culture (polystaphylococcal synovial fluid culture). In total, 340 patients were included in the analysis (no infection, 67% [226 of 340]; staphylococcal infection, 21% [71 of 340]; other infection, 13% [43 of 340]). The preoperative synovial fluid analysis included a cell count and differential and bacterial culture. SASAs were measured using a multiplex immunoassay. The diagnosis of PJI was determined using the Infectious Diseases Society of America (IDSA) criteria [] and intraoperative tissue culture at the time of revision surgery was used as the gold standard (at least one positive intraoperative sample for a "virulent" organism (such as S. aureus) or two positive samples for a "non-virulent" (for example S. epidermidis)., Results: SASA increased the PPV compared with synovial fluid culture alone (92% [95% CI 82 to 97] versus 79% [95% CI 68 to 87]; p = 0.04); when stratified by site, an increase in PPV was seen in hip infections (100% [95% CI 89 to 100] versus 77% [95% CI 63 to 88]; p = 0.01) but not in knee infections (84% [95% CI 66 to 95] versus 80% [95% CI 64 to 91]; p = 0.75). A positive cell count and differential result increased the PPV of staphylococcal synovial fluid cultures compared with synovial fluid culture alone (86% [95% CI 70 to 95] versus 79% [95% CI 68 to 87]; p = 0.36); when stratified by site, no difference in hip and knee infections was observed (86% [95% CI 67 to 96] versus 77% [95% CI 63 to 88]; p = 0.42) and 86% [95% CI 70 to 95] versus 80% [95% CI 64 to 91]; p = 0.74)., Conclusion: SASA measurement improves the predictive value of synovial fluid cultures of the hip for all staphylococcal organisms, including coagulase-negative staphylococci, but the PPV of SASA plus synovial fluid culture it is not superior to the PPV of synovial fluid cell count/differential plus synovial culture for the knee., Level of Evidence: Level III, diagnostic study.

Objective: Prosthetic joint infection (PJI) is a serious complication of joint replacement surgery. The major pharmacological and surgical treatments required by PJI increase the risk of peri-operative complications in elderly patients. The increase in life expectancy combined with procedural advances make these treatments possible even in the oldest patients. Here, our objective was to compare the characteristics and outcomes of curative PJI treatment in patients < 80 years vs. ≥ 80 years., Methods: A prospective single-center design was used to compare the characteristics and outcomes of curative treatment for hip or knee PJI in patients < 80 years and ≥ 80 years admitted in 2004-2014., Results: Of 765 patients admitted for PJI, 590 were < 80 years and 124 were ≥ 80 years. Medical history and comorbidities were similar in the two groups. The older group had a significantly higher proportion of patients with American Society of Anesthesiologists Scores ≥ 3 and with streptococcal infection (20% vs. 13%, P < 0.05). After complete surgical excision and prolonged antibiotic therapy, the only event whose frequency differed significantly between the two groups was PJI-related death, which was more common in the older patients (6.5% vs. 0.8%, P < 0.05). The 2-year survival rate after one-stage exchange arthroplasty was > 90% in the  ≥80 year group., Conclusion: Patients aged 80 years or older are eligible for the same curative pharmacological and surgical PJI treatments used in their younger counterparts. Before surgery, the risk/benefit ratio of the major surgical procedure required to treat PJI must be assessed on a case-by-case basis., (Copyright © 2019. Published by Elsevier Masson SAS.)

Background: Cutibacterium spp. (formerly Propionibacterium) are slow-growing cutaneous anaerobic commensals, rarely reported in prosthetic joint infections (PJIs). We describe epidemiological, clinical, biological, and radiological characteristics of 15 Cutibacterium avidum PJIs, their treatments, and outcomes., Methods: This study is an observational, monocenter study (January 2004 to April 2017), with comparison of C avidum vs Cutibacterium acnes (n = 40) PJI characteristics., Results: Among 1179 PJIs treated during the study period, 15 (1%) PJIs were due to C avidum (14 classified as late chronic and 1 as early postoperative). They involved only obese patients with hip arthroplasties (median age 65 years, body mass index 35 kg/m 2 ). Twelve patients' PJIs developed after primary hip arthroplasty. Thirteen patients' last clean operation had used an anterior approach. Fourteen preoperative joint aspirate cultures yielded C avidum. The 14 chronic PJIs were treated with 1-stage exchange arthroplasty, the acute case with excision synovectomy. Antibiotic therapy was administered for 12 [6-13] weeks, intravenously for 4 [2-6] weeks. The most used first-line agents were intravenous clindamycin (n = 8) or cefazolin (n = 6). After median follow-up of 27 [3-136] months, 1 relapse occurred. Compared to C acnes PJI patients, those with C avidum PJIs were significantly younger, had higher body mass indices, had only hip involvement, and had more frequent anterior surgical approach. C acnes PJIs were more frequent after revision arthroplasty., Conclusion: C avidum is a rare PJI agent occurring in a particular subpopulation. Joint aspiration is the key diagnostic tool. Our results suggest that PJI risk factors include obesity, primary hip arthroplasty, and anterior surgical approach. Efforts to prevent these infections in high-risk patients should be developed., (Copyright © 2018 Elsevier Inc. All rights reserved.)

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., (Copyright © 2018 The British Infection Association. Published by Elsevier Ltd. All rights reserved.)

We developed and evaluated a multiplex antibody detection-based immunoassay for the diagnosis of prosthetic joint infections (PJIs). Sixteen protein antigens from three Staphylococcusspecies (Staphylococcus aureus,Staphylococcus epidermidis, and Staphylococcus lugdunensis) (8 antigens),Streptococcus agalactiae(4 antigens), and Propionibacterium acnes(4 antigens) were selected by comparative immune proteomics using serum samples from PJI cases versus controls. A bead-based multiplex immunoassay that measured serum IgG against purified, recombinant forms of each of the 16 antigens was developed. We conducted a prospective study to evaluate the performance of the assay. A PJI was defined by the presence of a sinus tract and/or positive intraoperative sample cultures (at least one sample yielding a virulent organism or at least two samples yielding the same organism). A total of 455 consecutive patients undergoing revision or resection arthroplasty (hip, 66.3%; knee, 29.7%; shoulder, 4%) at two French reference centers for the management of PJI were included: 176 patients (38.7%) were infected and 279 (61.3%) were not. About 60% of the infections involved at least one of the species targeted by the assay. The sensitivity/specificity values were 72.3%/80.7% for targeted staphylococci, 75%/92.6% forS. agalactiae, and 38.5%/84.8% forP. acnes The assay was more sensitive for infections occurring >3 months after arthroplasty and for patients with an elevated C-reactive protein (CRP) or erythrocyte sedimentation rate (ESR). However, it detected 64.3% and 58.3% of targeted staphylococcal infections associated with normal CRP and ESR values, respectively. This new multiplex immunoassay approach is a novel noninvasive tool to evaluate patients suspected of having PJIs and provides information complementary to that from inflammatory marker values., (Copyright © 2016 Marmor et al.)

Background: Mycobacterium massiliense is closely related to Mycobacterium abscessus and is also a frequent cause of mycobacterial lung disease in patients with cystic fibrosis (CF). There has been no previous investigation of possible differences between M. massiliense and M. abscessus infections in the setting of CF., Methods: We studied a prospective cohort of 16 M. massiliense and 27 M. abscessus lung infection cases with CF, with a mean follow-up of 6 years., Results: M. massiliense cases were younger than M. abscessus cases (mean age: 12.8 vs 17.1 years; p=0.02) at the time of the first mycobacterial isolation and also had lower body mass index values (mean: 16.4 vs 19.3 kg/m(2), p=0.002). All M. massiliense cases, except one, had negative BMI Z-score values at the time of the first mycobacterial isolation (11/12 vs 16/23 M. abscessus cases, p=0.04). Clarithromycin-based combination therapies led to mycobacterial eradication in 100% of M. massiliense cases but only in 27% of M. abscessus cases (p=0.009)., Conclusion: Our data show a particular link between M. massiliense and malnutrition specifically in CF patients. Unlike M. abscessus, the bacteriological response of M. massiliense to combination antibiotic therapies containing clarithromycin was excellent. Distinguishing between M. massiliense and M. abscessus has major clinical implications for CF patients., (Copyright © 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.)

Mycobacterium abscessus, Mycobacterium bolletii, and Mycobacterium massiliense (Mycobacterium abscessus sensu lato) are closely related species that currently are identified by the sequencing of the rpoB gene. However, recent studies show that rpoB sequencing alone is insufficient to discriminate between these species, and some authors have questioned their current taxonomic classification. We studied here a large collection of M. abscessus (sensu lato) strains by partial rpoB sequencing (752 bp) and multilocus sequence analysis (MLSA). The final MLSA scheme developed was based on the partial sequences of eight housekeeping genes: argH, cya, glpK, gnd, murC, pgm, pta, and purH. The strains studied included the three type strains (M. abscessus CIP 104536(T), M. massiliense CIP 108297(T), and M. bolletii CIP 108541(T)) and 120 isolates recovered between 1997 and 2007 in France, Germany, Switzerland, and Brazil. The rpoB phylogenetic tree confirmed the existence of three main clusters, each comprising the type strain of one species. However, divergence values between the M. massiliense and M. bolletii clusters all were below 3% and between the M. abscessus and M. massiliense clusters were from 2.66 to 3.59%. The tree produced using the concatenated MLSA gene sequences (4,071 bp) also showed three main clusters, each comprising the type strain of one species. The M. abscessus cluster had a bootstrap value of 100% and was mostly compact. Bootstrap values for the M. massiliense and M. bolletii branches were much lower (71 and 61%, respectively), with the M. massiliense cluster having a fuzzy aspect. Mean (range) divergence values were 2.17% (1.13 to 2.58%) between the M. abscessus and M. massiliense clusters, 2.37% (1.5 to 2.85%) between the M. abscessus and M. bolletii clusters, and 2.28% (0.86 to 2.68%) between the M. massiliense and M. bolletii clusters. Adding the rpoB sequence to the MLSA-concatenated sequence (total sequence, 4,823 bp) had little effect on the clustering of strains. We found 10/120 (8.3%) isolates for which the concatenated MLSA gene sequence and rpoB sequence were discordant (e.g., M. massiliense MLSA sequence and M. abscessus rpoB sequence), suggesting the intergroup lateral transfers of rpoB. In conclusion, our study strongly supports the recent proposal that M. abscessus, M. massiliense, and M. bolletii should constitute a single species. Our findings also indicate that there has been a horizontal transfer of rpoB sequences between these subgroups, precluding the use of rpoB sequencing alone for the accurate identification of the two proposed M. abscessus subspecies.

Three types of multidrug-resistant Escherichia coli isolates, called GEN S, GEN R, and AMG S, according to their three different aminoglycoside resistance patterns, were responsible for urinary tract colonization or infection in 87, 12, and 13 new patients, respectively, in a French 650-bed geriatric hospital over a 13-month period. The three E. coli types belonged to the same clone and phylogenetic group (group B2) and had identical transferable plasmid contents (a 120-kb plasmid), beta-lactam and fluoroquinolone resistance genotypes (bla(TEM-1B), bla(CTX-M-15), and double mutations in both the gyrA and the parC genes), and virulence factor genotypes (aer, fyuA, and irp2). They disseminated in the geriatric hospital, where the antibiotics prescribed most often were fluoroquinolones and ceftriaxone, but not in the affiliated acute-care hospital, where isolation precautions were applied to the transferred patients. Thus, E. coli isolates, both CTX-M-type beta-lactamase producers and fluoroquinolone-resistant isolates, might present a new challenge for French health care settings.