In vitro activity of ceftazidime/avibactam, cefiderocol, meropenem/vaborbactam and imipenem/relebactam against clinical strains of the Stenotrophomonas maltophilia complex.

BACKGROUND: Infections caused by Stenotrophomonas maltophilia and related species are increasing worldwide. Unfortunately, treatment options are limited, whereas the antimicrobial resistance is increasing. METHODS: We included clinical isolates identified as S. maltophilia by VITEK 2 Compact. Ceftazidime/avibactam, meropenem/vaborbactam, imipenem/relebactam, cefiderocol, quinolones, and tetracycline family members were evaluated by broth microdilution method and compared with first-line treatment drugs. Minimum inhibitory concentrations (MICs) were reported for all antibiotics. We sequenced the Whole Genome of cefiderocol resistant strains (CRSs) and annotated their genes associated with cefiderocol resistance (GACR). Presumptive phylogenetic identification employing the 16S marker was performed. RESULTS: One hundred and one clinical strains were evaluated, sulfamethoxazole and trimethoprim, levofloxacin and minocycline showed susceptibilities of 99.01%, 95.04% and 100% respectively. Ceftazidime was the antibiotic with the highest percentage of resistance in all samples (77.22%). Five strains were resistant to cefiderocol exhibiting MIC values ≥ 2 µg/mL (4.95%). The ß-lactamase inhibitors meropenem/vaborbactam and imipenem/relebactam, failed to inhibit S. maltophilia, preserving both MIC50 and MIC90 ≥64 µg/mL. Ceftazidime/avibactam restored the activity of ceftazidime decreasing the MIC range. Tigecycline had the lowest MIC range, MIC50 and MIC90. Phylogeny based on 16S rRNA allowed to identify to cefiderocol resistant strains as putative species clustered into Stenotrophomonas maltophilia complex (Smc). In these strains, we detected GARCs such as Mutiple Drug Resistance (MDR) efflux pumps, L1-type ß-lactamases, iron transporters and type-1 fimbriae. CONCLUSION: Antimicrobial resistance to first-line treatment is low. The in vitro activity of new ß-lactamase inhibitors against S. maltophilia is poor, but avibactam may be a potential option. Cefiderocol could be considered as a potential new option for multidrug resistant infections. Tetracyclines had the best in vitro activity of all antibiotics evaluated.

Chronic Kidney Disease Risk Profile in Renal Donors in Aguascalientes, Mexico: A Retrospective Cohort Study.

BACKGROUND: In the last decade, kidney donation has been recognized as a risk factor for end-stage renal disease (ESRD). ESRD risk calculators have been recently perfected in North American populations. In Mexico, the rates of overweight, obesity, and diabetes mellitus (DM) are among the highest worldwide; nevertheless, most kidney transplants are obtained from living donors. This study aims to describe the risk profile for chronic kidney disease (CKD) development in kidney donors in a highly active transplant center in Central Mexico. METHODS: We conducted a retrospective, observational, descriptive cohort study of kidney donors followed at the Hospital Centenario Miguel Hidalgo (CHMH). We used the pretransplant CKD risk calculator at 15 years and over a lifetime (www.transplantmodels.com/esrdrisk). Aside from the calculator of kidney failure risk, we also used the calculator for postdonation CKD risk (www.transplantmodels.com/donesrd/). Factors associated with a glomerular filtration rate (GFR) <60 mL/min were evaluated by univariate and multivariate analysis. RESULTS: The study included 543 donors. The average follow-up period was 1.7 years (±2.7) with a median of 0.7 years (interquartile range, 0.2-2.1). The average predicted risk for ESRD development at 15 years was 0.08% (±0.1); 25.6% had a risk >0.1%, and only 1 patient had a risk >1%. The lifetime ESRD risk was 0.62% (±0.5); 15% had a risk >1%, and the greatest risk was 3.5%. The median of patients at risk of developing postdonation ESRD was 1 in 10,000 donors (0.6-1.5) at 5 years, 5.7 in 10,000 donors (3.5-8.8) at 10 years, 15 in 10,000 donors (9.1-23.2) at 15 years, and 31 in 10,000 donors (18.9-47.7) at 20 years. During the follow-up period, 52 patients developed a GFR of <60 mL/min. Both risk estimation formulas were significantly associated with a GFR of <60 mL/min. Among the individual factors, the GFR (hazard ratio 0.96, 95% confidence interval 0.94-0.97, P < .001) and the urinary albumin to creatinine ratio (hazard ratio 1.009, 95% confidence interval 1.005-1.01, P < .001) remained statistically significant. CONCLUSION: The risk of ESRD in kidney donors in Aguascalientes, Mexico, is similar to that described in the United States. Risk calculators are an indispensable decision-making tool to better understand kidney donors in our milieu.