Dalbavancin as suppressive therapy for implant-related infections: a case series with therapeutic drug monitoring and review of the literature.

Implant-related infections may need suppressive antibiotic therapy (SAT). We describe a SAT strategy using dalbavancin with therapeutic drug monitoring (TDM). This is a retrospective bicentric study of patients with implant-related infection who received dalbavancin SAT between January 2021 and September 2023. Fifteen patients were included. Median number of injections was 4 (IQR: 2-7). Median time between two reinjections was 57 days (IQR 28-82). Dalbavancin plasma concentrations were above 4 mg/L for 97.9% of dosages (93/95) and above 8 mg/L for 85% (81/95). These results support the use of dalbavancin SAT for implant-related infections.

Rifabutin versus rifampicin bactericidal and antibiofilm activities against clinical strains of Staphylococcus spp. isolated from bone and joint infections.

BACKGROUND: Staphylococci account for approximately 60% of periprosthetic joint infections (PJIs). Rifampicin (RMP) combination therapy is generally considered to be the treatment of choice for staphylococcal PJIs but carries an important risk of adverse events and drug-drug interactions. Rifabutin (RFB) shares many of the properties of rifampicin but causes fewer adverse events. OBJECTIVES: To compare the minimal inhibitory concentration (MIC), the minimum bactericidal concentrations (MBC), and the minimum biofilm eradication concentrations (MBEC) of rifabutin and rifampicin for staphylococcal clinical strains isolated from PJIs. METHODS: 132 clinical strains of rifampicin-susceptible staphylococci [51 Staphylococcus aureus (SA), 48 Staphylococcus epidermidis (SE) and 33 other coagulase-negative staphylococci (CoNS)] were studied. The MBC and the MBEC were determined using the MBEC® Assay for rifabutin and rifampicin and were compared. RESULTS: When compared with the rifampicin MIC median value, the rifabutin MIC median value was significantly higher for SA (P < 0.05), but there was no statistically significant difference for SE (P = 0.25) and CoNS (P = 0.29). The rifabutin MBC median value was significantly higher than that of rifampicin for SA (P = 0.003) and was lower for SE (P = 0.003) and CoNS (P = 0.03). Rifabutin MBEC median value was statistically lower than that of rifampicin for all strains tested. CONCLUSIONS: Using the determination of MBEC values, our study suggests that rifabutin is more effective than rifampicin against clinical strains of Staphylococcus spp. obtained from PJIs. Using MBECs instead of MICs seems to be of interest when considering biofilms. In vivo higher efficacy of rifabutin when compared with rifampicin needs to be confirmed.

Features of cryptococcosis among 652 HIV-seronegative individuals in France: a cross-sectional observational study (2005-2020).

OBJECTIVES: We aimed to describe features and outcomes of cryptococcosis among HIV-seronegative individuals in a large surveillance network for cryptococcosis in France. METHODS: We included incident cases of cryptococcosis in HIV-seronegative individuals from 2005 to 2020. We compared patient characteristics, disease presentations, cryptococcal antigen results, and induction antifungal treatments according to underlying disease. We examined factors associated with 90-day mortality. Among patients with disseminated infections, we investigated whether receipt of flucytosine and polyene combination was associated with lower mortality. RESULTS: Among 652 individuals, 209 (32.1%) had malignancy, 130 (19.9%) were solid-organ transplant recipients, 204 (31.3%) had other immunocompromising conditions, and 109 (16.7%) had no reported underlying factor. The commonest presentations were disseminated infections (63.3%, 413/652) and isolated pulmonary infections (25.3%, 165/652). Solid-organ transplant patients were most likely to have disseminated infections and a positive serum cryptococcal antigen result. Patients with malignancy were older and less likely to receive a flucytosine-containing regimen for disseminated infections than others (58.7%, 78/133 vs. 73.2%, 194/265; p 0.029). The crude 90-day case-fatality ratio was 27.2% (95% CI, 23.5%-31.1%). Age ≥60 years (aOR: 2.75 [1.78-4.26]; p < 0.001), meningitis/fungaemia (aOR: 4.79 [1.80-12.7]; p 0.002), and malignancy (aOR: 2.4 [1.14-5.07]; p 0.02) were associated with higher 90-day mortality. Receipt of flucytosine and polyene combination was associated with lower 90-day mortality (aOR: 0.40 [0.23-0.71]; p 0.002) in multivariable analysis and inverse probability of treatment weighted analysis (aOR: 0.45 [0.25-0.80]; p 0.006). DISCUSSION: HIV-seronegative individuals with cryptococcosis comprise a wide range of underlying conditions with different presentations and outcomes, requiring a tailored approach to diagnosis and management.

Cryptococcus neoformans Infections Differ Among Human Immunodeficiency Virus (HIV)-Seropositive and HIV-Seronegative Individuals: Results From a Nationwide Surveillance Program in France.

Among 1107 cryptococcosis cases from the French surveillance network (2005-2020), the proportion of HIV-seronegative individuals has recently surpassed that of HIV-seropositive individuals. We observed marked differences in patient characteristics, disease presentations, cryptococcal antigen results, infecting species, and mortality according to HIV serostatus.