Impact of Low-Level-Viremia on HIV-1 Drug-Resistance Evolution among Antiretroviral Treated-Patients

to determine the emergence and evolution of DRAM during LLV in HIV-1-infected patients while receiving antiretroviral therapy (ART).Retrospective analysis of patients presenting a LLV episode defined as pVL between 40 and 500 c/mL on at least 3 occasions during a 6-month period or longer while on the same ART. Resistance genotypic testing was performed at the onset and at the end of LLV period. Emerging DRAM was defined during LLV if never detected on baseline genotype or before.48 patients including 4 naive and 44 pretreated (median 9 years) presented a LLV episode with a median duration of 11 months. Current ART included 2NRTI (94%), ritonavir-boosted PI (94%), NNRTI (23%), and/or raltegravir (19%). Median pVL during LLV was 134 c/mL. Successful resistance testing at both onset and end of the LLV episode were obtained for 37 patients (77%), among who 11 (30%) acquired at least 1 DRAM during the LLV period: for NRTI in 6, for NNRTI in 1, for PI in 4, and for raltegravir in 2. During the LLV period, number of drugs with genotypic resistance increased from a median of 4.5 to 6 drugs. Duration and pVL level of LLV episode, duration of previous ART, current and nadir CD4 count, number of baseline DRAM and GSS were not identified as predictive factors of resistance acquisition during LLV, probably due to limited number of patients.Persistent LLV episodes below 500 c/ml while receiving ART is associated with emerging DRAM for all drug classes and a decreasing in further therapeutic options, suggesting to earlier consider resistance monitoring and ART optimization in this setting

Serratia marcescens outbreak in the intensive care unit during the COVID-19 pandemic: A paradoxical risk?

International audienc

Evaluation of βLACTA™ test, a rapid test detecting resistance to third-generation cephalosporins in clinical strains of Enterobacteriaceae.

Since decades, third-generation cephalosporins (3GC) are major drugs to treat infections due to Enterobacteriaceae; growing resistance to these antibiotics makes important to rapidly detect such resistance. βLACTA™ test is a chromogenic test developed for detecting within 15 minutes 3GC-resistant isolates from cultures on solid media. A multi-center prospective study conducted in 5 French and Belgian hospitals evaluated the performances of this test on clinical isolates. Based on antibiotic susceptibility testing, strains resistant or intermediate to cefotaxime or ceftazidime were classified as 3GC-resistant and molecular characterization of this resistance was performed. The rate of 3GC-resistance was globally 13.9% (332/2387), 9.4% in Escherichia coli (132/1403), 25.6% in Klebsiella pneumoniae (84/328), 30.3% in species naturally producing inducible AmpC beta-lactamases (109/360), and 5.6% in Klebsiella oxytoca and Citrobacter koseri (7/124). The overall sensitivity and specificity of βLACTA™ test were 87.7% and 99.6% respectively, were 96 and 100% for E. coli and K. pneumoniae and were 67.4% and 99.6% for species naturally producing inducible AmpC beta-lactamase. False negative results were mainly related to 3GC-resistant strains producing AmpC beta-lactamase. Interestingly, the test was positive for all 3GC-resistant extended-spectrum beta-lactamase producing isolates (n=241). Positive predictive value was 97% and would remain ≥ 96% for prevalence of 3GC-resistance ranging between 10 and 30%. Negative predictive value was 99% for E. coli and K. pneumoniae and 89% for the species producing inducible AmpC beta-lactamase.In conclusion βLACTA™ test was found to be easy to use and efficient to predict resistance to third-generation cephalosporins, particularly in extended-spectrum beta-lactamase producing strains