Whole-genome analysis uncovers loss of blaZ associated with carriage isolates belonging to methicillin-resistant Staphylococcus aureus (MRSA) clone ST5-VI in Cape Verde.

OBJECTIVES: Surveillance studies for Staphylococcus aureus carriage are a primary tool to survey the prevalence of methicillin-resistant S. aureus (MRSA) in the general population, patients and healthcare workers. We have previously reported S. aureus carriage in various African countries, including Cape Verde. METHODS: Whole-genome sequences of 106 S. aureus isolates from Cape Verde were determined. RESULTS: Staphylococcus aureus carriage isolates in Cape Verde show high genetic variability, with the detection of 27 sequence types (STs) and three primary genetic clusters associated with ST152, ST15 and ST5. One transmission event with less than eight core-genome single nucleotide polymorphisms (cgSNP) differences was detected among the ST5-VI MRSA lineage. Genetic analysis confirmed the phenotypic resistance and allowed the identification of six independent events of plasmid or transposon loss associated with the deletion of blaZ in nine isolates. In the four ST5 MRSA isolates, loss of the blaZ plasmid coincided with the acquisition of SCCmec type VI and an unusual penicillin phenotype with a minimum inhibitory concentration (MIC) at the breakpoint, indicating an adaptation trend in this endemic lineage. Similar events of blaZ plasmid loss, with concomitant acquisition SCCmec elements, were detected among ST5 isolates from different geographical origins. CONCLUSION: Overall, the genome data allowed to place isolates in a phylogenetic context and to identify different blaZ gene deletions associated with plasmid or transposon loss. Genomic analysis unveiled adaptation and evolution trends, namely among emerging MRSA lineages in the country, which deserve additional consideration in the design of future infection control protocols.

A five-year retrospective study shows increasing rates of antimicrobial drug resistance in Cabo Verde for both Staphylococcus aureus and Escherichia coli.

OBJECTIVES: Data on baseline drug resistance important in informing future antimicrobial stewardship programs. So far, no data on the antimicrobial drug resistance of clinical isolates available for the African archipelago of Cabo Verde. METHODS: We performed a retrospective analysis over years (2013-17) of the drug susceptibility profiles of clinical isolates in the two main hospitals of Cabo Verde. For Escherichia coli and Staphylococcus aureus, representing 47% and 26% of all clinical isolates, the antimicrobial drug resistance profile was reported for six representative drugs. RESULTS: For E. coli we detected an increase in resistance to ampicillin, amoxicillin/clavulanic acid, ceftriaxone, ciprofloxacin and trimethoprim-and for S. aureus to methicillin, erythromycin and trimethoprim-sulfamethoxazole. This increase in both the most commonly isolated bacterial pathogens is alarm as it might compromise empirical treatment in a setting with limited access to laboratory testing. CONCLUSIONS: When compared to the published low resistance rates in carriage isolates, the more alarming situation in clinical isolates for S. aureus might encourage antimicrobial stewardship programs to reduce in hospital settings, possibly as part of the Cabo Verdean national plan against antimicrobial drug resistance.

Effects of high-fat diet on plasma lipids, adiposity, and inflammatory markers in ovariectomized C57BL/6 mice.

OBJECTIVE: We hypothesized that a high-fat (HF) diet aggravates ovariectomy-related complications. To test this hypothesis, ovariectomized (OVX) mice were fed a HF diet, and we investigated the lipid metabolism, adipose tissue remodeling, adipokines, and inflammatory cytokines. METHODS: To investigate the situation in a mouse model of ovariectomy, OVX and SHAM C57BL/6 mice fed a HF diet (60% fat) or standard chow (SC, 10% fat) were monitored for 18 wk. We evaluated daily food intake and weekly body weight. Mice were killed at 30 wk of age. Blood samples and adipose tissue were collected for biochemical, histologic, and molecular analysis. RESULTS: OVX groups showed atrophied uterus compared to the SHAM groups, ensuring the success of surgically induced menopause. Despite lower food intake, OVX-HF mice gained about 52% more weight and had heavier total body fats, especially in relation to ovarian fat pad (372%)-a visceral fat which is associated with increased pathogenicity in obesity, and showed larger adipocytes (30%) when compared to OVX-SC mice. Biochemical analysis showed that the OVX-HF mice had increased levels of serum total cholesterol (51%), greater serum triglycerides (158%), lower serum adiponectin (40%), and higher plasma leptin (323%) than OVX-SC mice. The obese group (OVX-HF) also had higher IL-6 levels than both SHAM-HF (241%) and OVX-SC mice (870%). CONCLUSION: OVX C57BL/6 mice fed HF diet had greater adipose fat pad, larger adipocytes, and increased inflammatory markers, reinforcing the idea that a HF diet aggravates the complications of ovariectomy-associated inflammation.