Anemia before reimplantation surgery - An overlooked modifiable risk factor of septic revision knee arthroplasty failure

Introduction: Preoperative anemia in patients undergoing a two-stage septic revision arthroplasty may be a factor of reinfection, even in the presence of aggressive antimicrobial therapy. Patient Blood Management (PBM) in such patients is challenging. We evaluate the impact of anemia existing before re-implantation on a failure rate after two-stage septic total knee arthroplasty (rTKA), and explore feasibility of a PBM strategy implementation in these patients. Materials and methods: A retrospective study of patients from January 2010 to January 2015 in a French regional referral center was performed. Patients undergoing a two-stage rTKA for infection after successful primary TKA were identified and followed up to 31.12.2018. The primary outcome (failure) was defined as surgical site infection after re-implantation requiring new surgery. The secondary outcomes were time to failure, the time between explantation/reimplantation, transfusion rate during the second stage. Preoperative anemia was defined as Hb level < 12 g/L before the re-implantation. Results: 69 patients were identified; 17 (24%) developed reinfection of rTKA in 105 [11.4–156] days. In these patients pre-implantation anemia was more frequent (n = 13(76.5%) in failed vs. n = 21(40%) in non-failed, p = 0.0110). During the explantation stage, there were no significant group differences in age, sex, comorbidity, type of spacer and antimicrobial therapy, iron supplementation, or transfusion rate. The median time between explantation/reimplantation surgery was 51 [43–71.5] days, indifferent between the two groups. Intraoperative transfusion during reimplantation was required in 12 (17%) patients, more frequent in failed patients. None of the patients had contraindications for the PBM strategy except the cell-saver use. Conclusion: In two-stage septic rTKA preoperative anemia was almost two times more frequent and associated with an elevated rate of septic failure. The time-frame between explantation and-re-implantation is sufficient to implement a PBM strategy for all anemic patients. Before-after studies would be of interest to determine the best PBM strategy to prevent anemia-associated septic failure in such a condition.

Phage Therapy as Adjuvant to Conservative Surgery and Antibiotics to Salvage Patients With Relapsing S. aureus Prosthetic Knee Infection

Objectives: To report the management of three consecutive patients with relapsing Staphylococcus aureus prosthetic knee infection (PKI) for whom explantation was not feasible who received a phage therapy during a “Debridement Antibiotics and Implant Retention” (DAIR) procedure followed by suppressive antimicrobial therapy.

Methods: Each case was discussed individually in our reference center and with the French National Agency (ANSM). The lytic activity of three phages targeting S. aureus, which was produced with a controlled and reproducible process, was assessed before surgery (phagogram). A hospital pharmacist extemporaneously assembled the phage cocktail (1 ml of 1 × 10¹⁰ PFU/ml for each phage) as “magistral” preparation (final dilution 1 × 10⁹ PFU/ml), which was administered by the surgeon directly into the joint, after the DAIR procedure and joint closure (PhagoDAIR procedure).

Results: Three elderly patients were treated with the PhagoDAIR procedure. Phagograms revealed a high susceptibility to at least two of the three phages. During surgery, all patients had poor local conditions including pus in contact to the implant. After a prolonged follow-up, mild discharge of synovial fluid persisted in two patients, for whom a subsequent DAIR was performed showing only mild synovial inflammation without bacterial persistence or super-infection. The outcome was finally favorable with a significant and impressive clinical improvement of the function.

Conclusions: The PhagoDAIR procedure has the potential to be used as salvage for patients with relapsing S. aureus PKI, in combination with suppressive antibiotics to avoid considerable loss of function. This report provides preliminary data supporting the setup of a prospective multicentric clinical trial.

Pseudomonas aeruginosa Implant-Associated Bone and Joint Infections: Experience in a Regional Reference Center in France

Background:P. aeruginosa implant-associated bone and joint infections (BJI) is considered to be one of the most difficult to treat BJI. The data focusing specifically on this pathogen are sparse, and it seems difficult to extrapolate the results obtained with Enterobacteriaceae.

Methods: We performed a retrospective observation study of all P. aeruginosa implant-associated BJI diagnosed at our institution from 2011 to 2018. We defined failure as any type of relapse, including persistence of the same P. aeruginosa, superinfection by another organism(s) or any other cause of relapse such as the need for a subsequent surgery. Nonparametric statistical methods were used to compare the study groups and Kaplan-Meier curves and multivariate Cox analysis and were used to detect determinants associated with treatment failure.

Results: A total of 90 patients (62% men, median age 60 years IQR 47–72) including 30 (33%) prosthetic-joint infections and 60 (66%) other implant-associated BJIs were studied. Most of them were acute (62%). During the prolonged follow-up, (median 20 months; IQR 9–37), 23 patients (26%) experienced treatment failure. Optimal surgical treatment (DAIR for acute forms, explantation, 1-stage or 2-stage exchange for others) was significantly associated with a higher success rate in the univariate analysis (p = 0.003). Sixty-four (71%) patients received effective initial treatment against P. aeruginosa administered and 81 of them (90%) did for at least 3 weeks: both these parameters correlated with a higher success rate. In the multivariate Cox-analysis optimal surgical treatment, IV effective treatment of at least 3 weeks and treatment with ciprofloxacin for at least 3 months proved to be independently associated to a better outcome in patients with P. aeruginosa implant-associated BJI.

Conclusion:P. aeruginosa implant-associated BJI is one of the most difficult-to-treat BJI, with a strong impact on the prognosis of the surgical strategy. An effective initial IV antibiotic treatment for at least 3 weeks seems to be required, followed by oral ciprofloxacin for a total duration of 3 months.

Computerized registry as a potential tool for surveillance and management of complex bone and joint infections in France: French registry of complex bone and joint infections

Aims

The French registry for complex bone and joint infections (C-BJIs) was created in 2012 in order to facilitate a homogeneous management of patients presented for multidisciplinary advice in referral centres for C-BJI, to monitor their activity and to produce epidemiological data. We aimed here to present the genesis and characteristics of this national registry and provide the analysis of its data quality.

Methods

A centralized online secured database gathering the electronic case report forms (eCRFs) was filled for every patient presented in multidisciplinary meetings (MM) among the 24 French referral centres. Metrics of this registry were described between 2012 and 2016. Data quality was assessed by comparing essential items from the registry with a controlled dataset extracted from medical charts of a random sample of patients from each centre. Internal completeness and consistency were calculated.

Results

Between 2012 and 2016, 30,607 presentations in MM were recorded corresponding to 17,748 individual patients (mean age 62.1 years (SD 18.4); 10,961 (61.8%) males). BJI was considered as complex for 63% of cases (n = 19,355), and 13,376 (44%) had prosthetic joint infections (PJIs). The controlled dataset, available for 19 centres, included 283 patients. Global consistency and completeness were estimated at 88.2% and 88.9%, respectively, considering missing items in the eCRFs as negative results.

Conclusion

This national registry is one of the largest prospective databases on BJI and its acceptable data quality parameters allow further use for epidemiological purposes.Cite this article: Bone Joint Res 2020;9(9):635-644.

Patterns of Hepatitis C Virus Transmission in Human Immunodeficiency Virus (HIV)-infected and HIV-negative Men Who Have Sex With Men

BACKGROUND

Sexually transmitted acute hepatitis C virus (HCV) infections (AHIs) have been mainly described in human immunodeficiency virus (HIV)-infected men who have sex with men (MSM). Cases in HIV-negative MSM are scarce. We describe the epidemic of AHI in HIV-infected and HIV-negative MSM in Lyon, France.

METHODS

All cases of AHI diagnosed in MSM in Lyon University Hospital from 2014 to 2017 were included. AHI incidence was determined in HIV-infected and in preexposure prophylaxis (PrEP)-using MSM. Transmission clusters were identified by construction of phylogenetic trees based on HCV NS5B (genotype 1a/4d) or NS5A (genotype 3a) Sanger sequencing.

RESULTS

From 2014 to 2017, 108 AHIs (80 first infections, 28 reinfections) were reported in 96 MSM (HIV-infected, 72; HIV-negative, 24). AHI incidence rose from 1.1/100 person-years (95 confidence interval [CI], 0.7-1.7) in 2014 to 2.4/100 person-years (95 CI, 1.1-2.6) in 2017 in HIV-infected MSM (P = .05) and from 0.3/100 person-years (95 CI, 0.06-1.0) in 2016 to 3.4/100 person-years (95 CI, 2.0-5.5) in 2017 in PrEP users (P < .001). Eleven clusters were identified. All clusters included HIV-infected MSM; 6 also included HIV-negative MSM. All clusters started with ≥1 HIV-infected MSM. Risk factor distribution varied among clusters.

CONCLUSIONS

AHI incidence increased in both HIV-infected and HIV-negative MSM. Cluster analysis suggests initial transmission from HIV-infected to HIV-negative MSM through chemsex and traumatic sexual practices, leading to mixed patterns of transmission regardless of HIV status and no overlap with the general population.

Subcutaneous suppressive antibiotic therapy for bone and joint infections: safety and outcome in a cohort of 10 patients

BACKGROUND

Optimal treatment of prosthetic joint infection and chronic osteomyelitis consists of surgical removal of biofilm-embedded bacteria, followed by a 6-12 week course of antimicrobial therapy. However, when optimal surgery is not feasible, oral prolonged suppressive antibiotic therapy (PSAT) is recommended to prevent prosthesis loosening and/or relapse of infection. Since 2010, we have used infection salvage therapy using off-label subcutaneous (sc) injection of a β-lactam as PSAT for patients in whom oral PSAT is not possible.

METHODS

A single-centre prospective cohort study (2010-18) reporting treatment modalities, efficacy and safety in all patients receiving sc PSAT. NCT03403608.

RESULTS

The 10 included patients (median age 79 years) had polymicrobial (n = 5) or MDR bacterial (n = 4) prosthetic joint infection (knee, n = 4; hip, n = 3) or chronic osteomyelitis (n = 3). After initial intensive therapy, seven patients received ertapenem, three patients received ceftriaxone and one patient received ceftazidime by sc injection (one patient received 8 days of ceftriaxone before receiving ertapenem). In one patient, sc PSAT failed with recurrent signs of infection under treatment. In three patients, sc PSAT had to be discontinued due to side effects; in only one of these was the sc route implicated (skin necrosis following direct sc injection and not gravity infusion). Median treatment duration was 433 days. In six patients, sc PSAT was successful with favourable outcome at the time of writing. Interestingly, three patients with MDR bacterial carriage at baseline lost this under PSAT during follow-up.

CONCLUSIONS

As salvage therapy, sc PSAT delivered by gravity infusion is a safe and interesting alternative when an optimal surgical strategy is not feasible and no oral treatment is available.

The Potential Innovative Use of Bacteriophages Within the DAC® Hydrogel to Treat Patients With Knee Megaprosthesis Infection Requiring "Debridement Antibiotics and Implant Retention" and Soft Tissue Coverage as Salvage Therapy

Infection is the most dramatic complication in patients with knee megaprosthesis. Its management is more complex in comparison with patients with primary arthroplasty, with a high risk of relapse. Lytic bacteriophages are considered to have a high potential in patients with prosthetic joint infection as it has been demonstrated that they have a synergistic anti-biofilm activity with antibiotics. The Defensive Antibacterial Coating (DAC®) hydrogel is a hydrogel available in the market that has been designed to prevent the adherence of bacteria on a prosthetic joint and to have the ability to transport and release anti-bacterial substances such as antibiotics. We report here the case of a patient with a catastrophic relapsing Staphylococcus aureus knee megaprosthesis infection without prosthesis loosening. We firstly perform phage susceptibility testing of the patient's strain to select an active cocktail, under the supervision of the French health authority. Then, we performed, as salvage therapy, a debridement and implant retention procedure with application of a selected cocktail of bacteriophages that was prepared extemporaneously within the DAC® hydrogel. A free flap for soft tissue coverage was required and empirical antibiotic treatment was started immediately after the surgery. Unfortunately, at 5 days after the surgery, while the local aspect of the surgical site was favorable, the patient developed myocardial infarction which required emergency stenting and dual antiplatelet therapy that were rapidly associated with bleeding at the surgical site, leading to a new prosthesis exposition. As a consequence, a transfemoral amputation was finally performed several months later. We also evaluated in vitro the impact of DAC® hydrogel on bacteriophage activity and showed that the selected phages were released very rapidly from the DAC® hydrogel, and then their titers were stable for at least 6 h. This case demonstrated the feasibility of the use of bacteriophages within a hydrogel to treat patients for knee megaprosthesis infection during a debridement procedure. The implementation requires identification of the pathogen before the debridement in order to perform phage susceptibility testing of the patient's strain and to identify a hospital pharmacist who will accept to do the preparation and to take the responsibility of the magistral preparation.

Plasma Cell Infiltration on Histopathological Samples of Chronic Bone and Joint Infections due to Cutibacterium acnes: A series of 21 Cases

Introduction: Histopathological definition of bone and joint infection (BJI) is based on Mirra's criterion (≥ 5 polymorphonuclears (PMNs) per field in 5 high power fields (HPFs)). However, this definition does not seem appropriate for chronic BJIs caused by slow-growing germs such as Cutibacterium acnes (C. acnes). The aim of this study was to confirm that Mirra's criterion is not adequate for diagnosis of BJIs due to C. acnes. The second objective was to determine if plasma cell infiltration could be useful for the diagnosis of chronic BJIs due to C. acnes. Methods: We retrospectively selected 25 consecutive patients from 2009 to 2013 with chronic BJIs due to C. acnes. Histological analysis was performed on the 21 cases with at least two C. acnes positive cultures. In addition of Mirra's criterion, the number of plasma cells (≥5 plasma cells/5 HPFs, defined as "CRIOAc Lyon's criterion") was implemented in the histopathological analysis. Patients were defined as infected, if at least one of the two criteria were present. Results: According to Mirra's and CRIOAc Lyon's criteria, positive histopathology was observed in 12 (57.1%) and 15 (71.4%) cases respectively. Considering the 9 cases with negative Mirra's criterion, high plasma cell infiltration (≥5 plasma cells per field/5 HPFs) was observed in 5 cases (55.6%), and low plasma cells infiltration (2-5 plasma cells per field/5 HPFs) was observed in 4 other cases (44.4%). Conclusions: Adding CRIOAc Lyon's criterion to Mirra's criterion might restore some histopathological diagnosis of chronic BJIs due to C. acnes when a chronic BJI is clinically suspected.

Medical innovations to maintain the function in patients with chronic PJI for whom explantation is not desirable: a pathophysiology-, multidisciplinary-, and experience-based approach

INTRODUCTION

PJI is the most dramatic complication after joint arthroplasty. In patients with chronic infection, prosthesis exchange is in theory the rule. However, this surgical approach is sometimes not desirable especially in elderly patients with multiple comorbidities, as it could be associated with a dramatic loss of function, reduction of the bone stock, fracture, or peroperative death. We propose here to report different approaches that can help to maintain the function in such patients based on a pathophysiology-, multidisciplinary-, and an experience-based approach.

METHODS

We describe the different points that are needed to treat such patients: (i) the multidisciplinary care management; (ii) understanding the mechanism of bacterial persistence; (iii) optimization of the conservative surgical approach; (iv) use of suppressive antimicrobial therapy (SAT); (v) implementation of innovative agents that could be used locally to target the biofilm.

RESULTS

In France, a nation-wide network called CRIOAc has been created and funded by the French Health ministry to manage complex bone and joint infection. Based on the understanding of the complex pathophysiology of PJI, it seems to be feasible to propose conservative surgical treatment such as "debridement antibiotics and implant retention" (with or without soft-tissue coverage) followed by SAT to control the disease progression. Finally, there is a rational for the use of particular agents that have the ability to target the bacteria embedded in biofilm such as bacteriophages and phage lysins.

DISCUSSION

This multistep approach is probably a key determinant to propose innovative management in patients with complex PJI, to improve the outcome.

CONCLUSION

Conservative treatment has a high potential in patients with chronic PJI for whom explantation is not desirable. The next step will be to evaluate such practices in nation-wide clinical trials.

Genetic polymorphisms of ABCB1 (P-glycoprotein) as a covariate influencing daptomycin pharmacokinetics: a population analysis in patients with bone and joint infection

BACKGROUND

Daptomycin has been recognized as a therapeutic option for the treatment of bone and joint infection (BJI). Gene polymorphism of ABCB1, the gene encoding P-glycoprotein (P-gp), may influence daptomycin pharmacokinetics (PK).

OBJECTIVES

We aimed to examine population PK of daptomycin and its determinants, including genetic factors, in patients with BJI.

PATIENTS AND METHODS

We analysed data from patients who received daptomycin for BJI between 2012 and 2016 in our regional reference centre and who had measured daptomycin concentrations and P-gp genotyping. A population approach was used to analyse PK data. In covariate analysis, we examined the influence of three single nucleotide variations (SNVs) of ABCB1 (3435C > T, 2677G > T/A and 1236C > T) and that of the corresponding haplotype on daptomycin PK parameters. Simulations performed with the final model examined the influence of covariates on the probability to achieve pharmacodynamic (PD) targets.

RESULTS

Data from 81 patients were analysed. Daptomycin body CL (CLDAP) correlated with CLCR and was 23% greater in males than in females. Daptomycin central V (V1) was allometrically scaled to body weight and was 25% lower in patients with homozygous CGC ABCB1 haplotype than in patients with any other genotype. Simulations performed with the model showed that sex and P-gp haplotype may influence the PTA for high MIC values and that a dosage of 10 mg/kg/24 h would optimize efficacy.

CONCLUSIONS

Daptomycin dosages higher than currently recommended should be evaluated in patients with BJI. Gender and P-gp gene polymorphism should be further examined as determinants of dosage requirements.

Integrase strand transfer inhibitors and neuropsychiatric adverse events in a large prospective cohort

OBJECTIVES

To analyse the frequency and causes of treatment discontinuation in patients who were treated with an integrase strand transfer inhibitor (INSTI), with a focus on neuropsychiatric adverse events (NPAEs).

METHODS

Patients in 18 HIV reference centres in France were prospectively included in the Dat'AIDS cohort. Data were collected from all patients starting an INSTI-containing regimen between 1 January 2006 and 31 December 2016. All causes of INSTI-containing regimen discontinuations were analysed, and patients' characteristics related to discontinuation due to NPAEs were sought.

RESULTS

INSTIs were prescribed to 21315 patients: 6274 received dolutegravir, 3421 received elvitegravir boosted by cobicistat, and 11620 received raltegravir. Discontinuation was observed in 12.5%, 20.2% and 50.9% of the dolutegravir-, elvitegravir- and raltegravir-treated patients, respectively (P < 0.001). Discontinuation for NPAEs occurred in 2.7%, 1.3% and 1.7% of the dolutegravir-, elvitegravir-, and raltegravir-treated patients, respectively (P < 0.001). In the multivariate analysis, discontinuation for NPAEs was related to dolutegravir versus elvitegravir (HR = 2.27; 95% CI 1.63-3.17; P < 0.0001) and versus raltegravir (HR = 2.46; 95% CI 2.00-3.40; P < 0.0001), but neither gender (HR for women = 1.19; 95% CI 0.97-1.46; P = 0.09) nor age (P = 0.12) was related. The association with abacavir was not retained in the final model.

CONCLUSIONS

Although discontinuation for side effects was less frequent with dolutegravir than with boosted elvitegravir, discontinuation for NPAEs, although rare (2.7%), was more frequent with dolutegravir. No patient characteristic was found to be associated with these side effects in this very large population.

Evaluation of the ability of linezolid and tedizolid to eradicate intraosteoblastic and biofilm-embedded Staphylococcus aureus in the bone and joint infection setting

OBJECTIVES

Prolonged use of linezolid for bone and joint infection (BJI) is limited by its long-term toxicity. The better safety profile of tedizolid, a recently developed oxazolidinone, could offer an alternative. However, its efficacy against biofilm-embedded and intracellular Staphylococcus aureus, the two main bacterial reservoirs associated with BJI chronicity, is unknown.

METHODS

Using three S. aureus strains (6850 and two clinical BJI isolates), linezolid and tedizolid were compared regarding their ability: (i) to target the S. aureus intracellular reservoir in an in vitro model of osteoblast infection, using three concentrations increasing from the bone concentration reached with standard therapeutic doses (Cbone = 2.5 × MIC; Cplasm = 10 × MIC; Cmax = 40 × MIC); (ii) to eradicate mature biofilm [minimal biofilm eradication concentration (MBEC)]; and (iii) to prevent biofilm formation [biofilm MIC (bMIC) and confocal microscopy].

RESULTS

Linezolid and tedizolid weakly reduced the intracellular inoculum of S. aureus in a strain-dependent manner despite the similar MICs for the tested strains, but improved cell viability even in the absence of an intracellular bactericidal effect. Conversely, linezolid and tedizolid were ineffective in eradicating mature biofilm formed in vitro, with MBEC >2000 and >675 mg/L, respectively. bMICs of tedizolid were 4-fold lower than those of linezolid for all strains.

CONCLUSIONS

Linezolid and tedizolid alone are not optimal candidates to target bacterial phenotypes associated with chronic forms of BJI. Despite weak intracellular activity, they both reduce infection-related cytotoxicity, suggesting a role in modulating intracellular expression of staphylococcal virulence factors. Although inactive against biofilm-embedded S. aureus, both-but particularly tedizolid-are able to prevent biofilm formation.

Efficacy and Safety of Revaccination against Tetanus, Diphtheria, Haemophilus influenzae Type b and Hepatitis B Virus in a Prospective Cohort of Adult Recipients of Allogeneic Hematopoietic Stem Cell Transplantation

Data on immunogenicity and safety of the recommended revaccination schedule against diphtheria, tetanus, poliomyelitis, pertussis, Haemophilus influenzae type b (Hib), and hepatitis B in adult allogeneic hematopoietic stem cell transplantation (allo-HSCT) recipients are limited. This prospective single-center cohort study (April 2014 to March 2018) included adult allo-HSCT recipients referred to a dedicated vaccinology consultation and vaccinated with the pediatric combined diphtheria, tetanus, acellular pertussis, hepatitis B virus, inactivated poliovirus, and Haemophilus influenzae type b (DTaP(±HB)-IPV-Hib) vaccine (3 doses 1 month apart, booster dose 1 year later). The proportion of responders to tetanus, diphtheria, Hib, and hepatitis B vaccine and geometric mean concentrations (GMCs) of antibodies were assessed before and up to 24 months after vaccination. A total of 106 patients were vaccinated at a median (interquartile range) time of 12.4 (10 to 18.4) months post-transplant. At 5.3 (4.8 to 6.6) and 23.1 (21.1 to 25.1) months after vaccine initiation, high and sustained rates of protective antibody titers were achieved for tetanus (97.8% [95% confidence interval (95% CI), 92.4% to 99.7%], n = 91/93 and 100% [95% CI, 92% to 100%], n = 44/44), diphtheria (94.6% [95% CI, 87.9% to 98.2%], n = 88/93 and 90.9% [95% CI, 78.3% to 97.5%], n = 40/44), Hib (96.6% [95% CI, 90.4% to 99.3%], n = 85/88 and 93% [95% CI, 80.9% to 98.5%], n = 40/43), and hepatitis B (83.5% [95% CI, 73.5% to 90.9%], n = 66/79 and 81.1% [95% CI, 64.8% to 92%], n = 30/37). Underlying disease, stem cell source, chronic graft-versus-host-disease, and extracorporeal photopheresis differentially influenced GMCs of tetanus, diphtheria, and hepatitis B antibodies after 3 doses but not in the long term (24 months). Six (5.7%) patients experienced mild side effects. The pediatric DTaP(±HB)-IPV-Hib vaccine was safe and effective in eliciting a sustained protective humoral response in adult allo-HSCT recipients. Hepatitis B revaccination might be optimized by using higher antigen doses.

Hematogenous osteomyelitis in childhood can relapse many years later into adulthood: A retrospective multicentric cohort study in France

To describe the epidemiological, clinical, laboratory, and radiological features and the management of adult patients who experienced a relapse between 2003 and 2015 of an acute hematogenous osteomyelitis acquired in childhood.A retrospective multicentric cohort study was conducted in 5 centers in France.Thirty-seven patients were included. The median age was 40 years (28-56), and 26 (70%) were male. The first site of infection was the distal femur (n = 23, 62%). The median time between the osteomyelitis in childhood and the relapse in adulthood was 26 years (13-45). Thirty-four (92%) patients reported inflammatory local clinical manifestations, 17 (46%) draining fistula, 10 (27%) fever. Most patients had intramedullary gadolinium deposition (with or without abscess) on magnetic resonance imaging. Most relapses were monomicrobial infections (82%). Staphylococcus aureus was the most commonly found microorganism (82%), expressing a small colony variant phenotype in 3 cases. Most patients (97%) had a surgical treatment, and the median duration of antibiotics for the relapse was 12 weeks. All patients had a favorable outcome, no patient died and no further relapse occurred. We count 2 femoral fractures on osteotomy site.Osteomyelitis in childhood can relapse later in adulthood, especially in patients with lack of care during the initial episode. Osteotomy and prolonged antimicrobial therapy are required for clinical remission.

Kaposi sarcoma among people living with HIV in the French DAT'AIDS cohort between 2010 and 2015

Background

Although antiretroviral therapy (ART) has reduced the risk of Kaposi sarcoma (KS), KS cases still occur in HIV‐infected people.

Objective

To describe all KS cases observed between 2010 and 2015 in a country with high ART coverage.

Methods

Retrospective study using longitudinal data from 44 642 patients in the French Dat’AIDS multicenter cohort. Patients’ characteristics were described at KS diagnosis according to ART exposure and to HIV‐plasma viral load (HIV‐pVL) (≤50 or >50) copies/mL.

Results

Among the 209 KS cases diagnosed during the study period, 33.2% occurred in ART naïve patients, 17.3% in ART‐experienced patients and 49.5% in patients on ART, of whom 23% for more than 6 months. Among these patients, 24 (11.5%) had HIV‐pVL ≤50 cp/mL, and 16 (66%) were treated with a boosted‐PI‐based regimen. The distribution of KS localization did not differ by ART status nor by year of diagnosis.

Limitations

Data on human herpesvirus 8, treatment modalities for KS and response rate were not collected.

Conclusion

Half of KS cases observed in the study period occurred in patients not on ART, reflecting the persistence of late HIV diagnosis. Factors associated with KS in patients on ART with HIV‐pVL ≤50 cp/mL remain to be explored.

Incidence and Clearance of Anal Human Papillomavirus (HPV)-16 and HPV-18 Infection, and Their Determinants, Among Human Immunodeficiency Virus-Infected Men Who Have Sex With Men in France

BACKGROUND

Prospective data on the natural history of anal human papillomavirus (HPV) infection are scarce in human immunodeficiency virus (HIV)-infected men who have sex with men (MSM).

METHODS

We analyzed incidence and clearance of HPV-16 and HPV-18 in a French cohort of HIV-infected MSM, aged ≥35 years, followed-up annually (n = 438, 2014-2018).

RESULTS

Human papillomavirus-16 and HPV-18 incidence were similar (~10% incident infections at 24 months). Human papillomavirus-16 incidence was higher among high-grade versus no lesion at baseline (adjusted incidence rate ratio = 3.0; 95% confidence interval, 1.07-8.18). Human papillomavirus-16 cleared significantly slower than HPV-18 (32% versus 54% by 24 months).

CONCLUSIONS

In conclusion, anal HPV-16 is more persistent than HPV-18, and its incidence correlates with a prior detection of high-grade lesions.

Antibiofilm and intraosteoblastic activities of rifamycins against Staphylococcus aureus: promising in vitro profile of rifabutin

Background

Targeting biofilm-embedded and intraosteoblastic Staphylococcus aureus, rifampicin gained a pivotal role in bone and joint infection (BJI) treatment. Two other rifamycins, rifabutin and rifapentine, may represent better-tolerated alternatives, but their activity against bacterial reservoirs associated with BJI chronicity has never been evaluated.

Objectives

To evaluate the activities of rifampicin, rifabutin and rifapentine in osteoblast infection models.

Methods

Using three S. aureus isolates, rifamycins were compared regarding: (i) their intracellular activity in ‘acute’ (24 h) and ‘chronic’ (7 days) osteoblast infection models at 0.1× MIC, 1× MIC, 10× MIC and 100× MIC, while impacting infection-induced cytotoxicity (MTT assay), intracellular phenol-soluble modulin (PSM) secretion (RT–PCR), resistance selection and small colony variant (SCV) emergence; and (ii) their minimal biofilm eradication concentration (MBEC) and their MIC to prevent biofilm formation (bMIC).

Results

At 0.1× MIC, only rifabutin significantly reduced intracellular inoculum and PSM secretion. All rifamycins allowed a 50% reduction of intraosteoblastic inoculum at higher concentrations, with no difference between acute and chronic infection models, while reducing infection-induced cytotoxicity and PSM secretion. Dose-dependent emergence of intracellular SCVs was observed for all molecules. No intracellular emergence of resistance was detected. bMICs were equivalent for all molecules, but MBEC90s of rifapentine and rifabutin were 10- to 100-fold lower than those of rifampicin, respectively.

Conclusions

All rifamycins are efficient in reducing the S. aureus intraosteoblastic reservoir while limiting infection-induced cytotoxicity, with a higher activity of rifabutin at low concentrations. All molecules prevent biofilm formation, but only rifapentine and rifabutin consistently reduce formed biofilm-embedded bacteria for all isolates. The activity of rifabutin at lower doses highlights its therapeutic potential.

Duration of rifampin therapy is a key determinant of improved outcomes in early-onset acute prosthetic joint infection due to Staphylococcus treated with a debridement, antibiotics and implant retention (DAIR): a retrospective multicenter study in France

Introduction: In patients undergoing a « debridement, antibiotics, and implant retention » (DAIR) procedure for acute staphylococcal prosthetic joint infection (PJI), post-operative treatment with rifampin has been associated with a higher probability of success.(1,2) However, it is not known whether it is the total dose, delay of introduction or length of therapy with rifampin that is most strongly associated with the observed improved outcomes.

Methods: A multicentric, retrospective cohort study of patients with acute staphylococcal hip and knee PJI treated with DAIR between January 2011 and December 2016. Failure of the DAIR procedure was defined as persistent infection, need for another surgery or death. We fitted logistic and Cox regression multivariate models to identify predictors of DAIR failure. We compared Kaplan-Meier estimates of failure probability in different levels of the 3 variables of interest - total dose, delay of introduction or length of therapy with rifampin - with the log-rank test.

Results: 79 patients included (median age 71 years [63.5-81]; 55 men [70%]), including 54 (68%) DAIR successes and 25 (32%) DAIR failures. Patients observed for a median of 435 days [IQR 107.5-834]. Median ASA score significantly lower in DAIR successes than in DAIR failures (2 vs. 3, respectively p = 0.011). Bacterial cultures revealed 65 (82.3%) S. aureus and 16 (20.3%) coagulase negative staphylococci, with 2 patients being infected simultaneously with S. aureus and CNS. Among S. aureus isolates, 7 (10.8%) resistant to methicillin; 2 (3.1 %) resistant to rifampin. Median duration of antimicrobial therapy was 85 days [IQR 28.5-97.8]. Fifty-eight patients (73.4%) received rifampin at a median dose of 14.6 mg/kg/day |IQR 13-16.7], started at a median delay of 8.5 days [IQR, 4-7.5] after debridement surgery. Twenty-one patients (26.6%) developed a drug-related adverse event, leading to rifampin interruption in 6 of them (7.6% of total cohort). Determinants of DAIR failure were rifampin use (HR 0.17, IC [0.06, 0.45], p-value <0.001), association of rifampin with a fluoroquinolone (HR 0.19, IC [0.07, 0.53], p-value = 0.002) and duration of rifampin therapy (HR 0.97, IC [0.95, 1], p-value = 0.022). We did not observe a significant difference between DAIR successes and failures in rifampin use, dose and delay of introduction. In a multivariate Cox model, only duration of rifampin therapy was significantly associated with DAIR failure. Kaplan Meier estimate of DAIR failure probability was significantly higher in patients receiving less than 14 days of rifampin in comparison with those receiving more than 14 days of rifampin (p = 0.0017).

Conclusion: Duration of rifampin therapy is a key determinant of improved outcomes in early-onset acute prosthetic joint infection due to Staphylococcus treated with DAIR.

Staphylococcus aureus Bloodstream Infection in Patients With Prosthetic Joints in the Prospective VIRSTA Cohort Study: Frequency and Time of Occurrence of Periprosthetic Joint Infection

Among 143 patients of the VIRSTA cohort study with Staphylococcus aureus bacteremia and an arthroplasty implanted for more than a year, S. aureus periprosthetic joint infection was observed in 19%. Signs of infection (pain and swelling) were always present, in median 1 day (range, 0–21 days) after onset of bacteremia.

Staphylococcus aureus has both a high potential for metastatic infection and a high affinity for foreign material. Possible prosthesis infection is of clinical concern in all patients with preexisting prosthetic materials experiencing S. aureus bloodstream infection (SAB). Prosthetic joints are especially prone to infection during the course of bacteremia, with a risk of infection much higher with S. aureus than with other microorganisms, 20% vs 7%, in a recent prospective study [1]. As early intervention with debridement in prosthetic joint infection (PJI) is paramount to retain the implant and to prevent infection relapse; eliminating PJI after SAB is important. However, additional data are needed to better describe the clinical characteristics of PJI after SAB in particular time lapses and whether systematic imaging of the prosthesis could be necessary after SAB. We described the frequency and clinical presentation of PJIs observed among patients with prosthetic joints implanted for >1 year before bacteremia and enrolled in the VIRSTA study, a multicenter prospective cohort study of patients with SAB.