The humoral response of mRNA COVID-19 vaccine in hematological diseases: The HEMVACO study.

OBJECTIVES: The HEMVACO study evaluated the humoral response after mRNA anti-SARS-CoV-2 vaccination in an hematological cohort. METHODS: HEMVACO was a prospective, multicentric study registered in ClinicalTrials.gov, number NCT04852796. Patients received two or three doses of BNT162b2 vaccine or mRNA-1273 vaccine. The SARS-CoV-2 TrimericS IgG titers were measured 1, 3, 6 and 12 months after the second dose. RESULTS: Only 16 patients (11.6%) were naive of hematological treatment and 77 patients (55.8%) were on active treatment for hemopathy. Among the 138 analyzed patients, positive antibody titer at 1 month was obtained in 68.1% of patients with mean serology at 850±883 BAU/ml. Risk factors for vaccine failure were anti-CD20 therapy (OR=111[14.3-873]; P<0.001), hypogammaglobulinemia under 8g/L (OR=2.49[1.05-5.92]; P=0.032) and lymphopenia under 1.5G/L (OR=2.47[1.18-5.17]; P=0.015). Anti-CD20 therapy induced no anti-SARS-CoV-2 seroconversion (96%). Seventy-eight patients (56.5%) received a third dose and could reach the SARS-CoV-2 TrimericS IgG titer of high-risk patients (P=0.54). The median titer at 379 BAU/ml distinguished two groups of vaccine response (99±121 BAU/ml versus 1,109±678 BAU/ml). CONCLUSION: Vaccination should be performed before anti-CD20 therapy if the hemopathy treatment can be delayed. Administration of the third vaccine dose was interesting for patients with suboptimal response, defined by a 379 BAU/ml titer in our study.

Elizabethkingia anophelis outbreak in France.

OBJECTIVE: We report an outbreak of Elizabethkingia anophelis infections in France. To the best of our knowledge, this is the first outbreak described in Europe. METHODS: Each E. anophelis-positive microbiological sample was considered a case. All patients were hospitalized in an infectious diseases unit. Clinical, environmental, and microbiological investigations (MALDI-TOF mass spectrometry, PCR, E-test) were performed for each case. RESULTS: Twenty cases were reported from September 2020 to September 2021, mainly community-acquired infections, responsible for nine deaths. The phylogenetic analysis showed a clonal origin and excluded nosocomial transmission. Despite the analysis of multiple environmental specimens, no source of contamination was identified. All strains were highly resistant to cefotaxime, ceftazidime, and imipenem. CONCLUSIONS: Clinicians and microbiologists should be aware of this multidrug-resistant bacterium, capable of causing severe infections. Most strains showed the lowest minimum inhibitory concentration values for cotrimoxazole and ciprofloxacin, making them the best choice for empirical antibiotic therapy.

Switching from abacavir/lamivudine plus nevirapine to abacavir/lamivudine/dolutegravir in virologically controlled HIV-infected adults (SWAD study).

INTRODUCTION: The metabolic pathways of dolutegravir suggest a potential predator effect of nevirapine on dolutegravir pharmacokinetics and switching from a nevirapine- to a dolutegravir-containing regimen could lead to a lower and suboptimal exposure to dolutegravir several weeks after the switch in case of persistent inducer effect. PATIENTS AND METHOD: Prospective, pilot, single-arm, open-label, non-comparative, bicentric study to evaluate the pharmacokinetics, virologic outcomes, safety, and patient satisfaction of switching from abacavir/lamivudine and nevirapine to a single tablet of abacavir/lamivudine/dolutegravir. The primary endpoint was the maintenance of virologic suppression (HIV-1 RNA<50 copies/mL) at week 12. Secondary endpoints were virologic suppression at week 48, safety and tolerability, patient satisfaction, and pharmacokinetic interaction between nevirapine and dolutegravir. Fifty-three adults on stable abacavir/lamivudine and nevirapine regimen for a median duration of 6years and virologically suppressed for 9.6years were included. RESULTS: Dolutegravir reached steady state by week 4/week 12 when expected by day 5/day 10. All subjects maintained plasma HIV-RNA˂50 copies/mL at week 12 and week 48. Abacavir/lamivudine/dolutegravir was well-tolerated, with two cases of serious adverse events deemed unrelated to study drugs (coronary syndrome in both cases), and one discontinuation for renal impairment at week 24 with a slight improvement after dolutegravir discontinuation. Level of treatment satisfaction remained high after the switch. CONCLUSION: The transient predator effect of nevirapine on dolutegravir had no clinical consequences after switching from nevirapine to dolutegravir, neither on safety nor maintenance of virologic suppression. It also had no consequences on patient satisfaction.

Bacteriological relevance of linezolid vs. vancomycin in postoperative empirical treatment of osteoarticular infections: a retrospective single-center study.

BACKGROUND: In 2015, our center replaced vancomycin with linezolid for the postoperative empirical treatment of osteoarticular infections (OAI). OBJECTIVES: To assess the bacteriological relevance of linezolid for orthopedic postoperative probabilistic antibiotic therapy. METHODS: Analysis of an observational cohort of patients empirically treated with a combination of linezolid and piperacillin/tazobactam during the immediate postoperative stage for an OAI between July 1st 2015 and July 1st 2016, in a French reference center. RESULTS: Seventy-seven of 126 patients who received a probabilistic postoperative combination of linezolid with piperacillin/tazobactam had microbiological proof of infection. Sixty-six of 77 OAI involved material, including an osteosynthesis in 45 cases (68%) and prosthesis in 21 cases (32%). Infection was due to Gram-positive bacteria in 62 cases (80.5%), mostly S. aureus (n=32, 41.6%), and S. epidermidis (n=14, 18.2%) accounting for 74.2% of Gram-positive bacteria. Among 14 OAI due to S. epidermidis, 11 (78.6%) were due to methicillin-resistant strains. All the S. aureus and S. epidermidis strains were susceptible to linezolid (MICs ≤ 4 mg/L), except in one patient previously treated with linezolid who was infected with a linezolid-resistant S. epidermidis strain (MIC > 256 mg/L). CONCLUSION: Linezolid can be used empirically in postoperative antibiotic therapy of OAI before obtaining definitive microbial results. Although linezolid resistance is rare in this population, previous oxazolidinone treatment should be documented before initiation of probabilistic postoperative treatment to highlight potential linezolid resistance.