Evaluation of two commercial broth microdilution systems for dalbavancin susceptibility testing of methicillin-resistant Staphylococcus aureus and other resistant Gram-positive cocci.

OBJECTIVES: This study aims to evaluate two commercial broth microdilution (BMD) systems, E1-185-100 (Merlin) and FDANDPF (ThermoFisher), for dalbavancin susceptibility testing in comparison with reference BMD assay. METHODS: Study collection was composed of 200 non-replicate multidrug-resistant Gram-positive cocci of clinical origin, including 180 methicillin-resistant Staphylococcus aureus, 10 vancomycin-resistant enterococci, seven linezolid-resistant Staphylococcus epidermidis, and three methicillin-resistant coagulase-negative staphylococci. S. aureus ATCC 29213 and Enterococcus faecalis ATCC 29212 reference strains were also included as controls. Testing was performed according to the ISO 20776-1 standard, starting from the same bacterial inoculum, and results were compared according to the ISO 20776-2 standard. RESULTS: Reference BMD showed that 92.6% (187/202) of the strains were susceptible to dalbavancin, whereas few staphylococci and all VanA-producing enterococci showed a resistant phenotype. In comparison with the reference method, Category Agreement and Essential Agreement were 98% (198/202; 95% CI, 95.4-99.3%) and 98% (198/202; 95% CI, 95.4-99.3%) for both Merlin and ThermoFisher panels. A few false susceptibilities were observed, for both commercial systems, with dalbavancin-resistant staphylococci. BIAS values of 11% and 3% were calculated for the Merlin and ThermoFisher systems, respectively. DISCUSSION: This study, reporting the first evaluation of the two commercially available BMD assays for dalbavancin susceptibility testing, revealed an overall good correlation with reference BMD, although with some underestimation tendency of MIC values by both commercial systems. Further studies involving a higher number of resistant isolates will be necessary to better evaluate this issue.

Evaluation of antibiofilm activity of cefiderocol alone and in combination with imipenem against Pseudomonas aeruginosa.

OBJECTIVES: The main aim of this study was to evaluate the antibiofilm activity of cefiderocol alone and in combination with imipenem vs. sessile cells of Pseudomonas aeruginosa, assessing a potential synergistic bactericidal effect. METHODS: Ten P. aeruginosa clinical isolates from infected implants and bloodstream were included in the study. Cefiderocol was tested alone and in combination with imipenem on 24-h-old P. aeruginosa biofilm formed on porous glass beads. For each antibiotic formulation, minimum bactericidal biofilm concentration (MBBC), defined as the lowest concentration that determined a reduction of at least 3 log10 CFU/mL compared with the untreated control, was evaluated. Scanning electron microscopy (SEM) was used to investigate the biofilm of P. aeruginosa treated with cefiderocol, imipenem, or their combination. RESULTS: Cefiderocol and imipenem were tested alone on P. aeruginosa biofilm and a reasonable reduction in the number of viable cells was observed, especially at high drug concentrations tested. The synergistic effect of cefiderocol in combination with imipenem was evaluated for five selected isolates. Cotreatment with the two drugs led to a remarkable reduction of cell viability by resulting in synergistic bactericidal activity in all tested strains and in synergistic eradicating activity in only one isolate. SEM analysis revealed that, in cefiderocol-treated biofilm, bacterial cells became more elongated than in the untreated control, forming filaments in which bacterial division seems to be inhibited. CONCLUSIONS: Cefiderocol exhibited an encouraging antibiofilm activity against tested strains, representing a valid option for the treatment of P. aeruginosa biofilm-associated infections, especially when administered in combination with imipenem.

Changes in the maternal serum concentration of proearly placenta insulin-like growth factor peptides in normal vs abnormal pregnancy.

OBJECTIVE: The objective of the study was to evaluate maternal serum pro-early placenta insulin like (proEPIL) levels during normal and pathologic pregnancy by using a newly developed enzyme-linked immunosorbent assay, based on a monoclonal antibody designated EPIL15 and directed to the pro-EPIL C-chain 98-108 region. STUDY DESIGN: In a group of healthy pregnant women (n = 22), proEPIL peptide serum levels were measured longitudinally throughout gestation (8-12, 20-24, and 30-34 weeks). Serum proEPIL levels were measured in women with preterm labor (n = 24), intrauterine growth restriction (n = 27), and preeclampsia (n = 12). RESULTS: In healthy pregnant women, a significant rise of serum pro-EPIL levels (mean +/- SEM) was observed during the third trimester of gestation (30.97 +/- 2.978 ng/mL; P < .01), with the highest serum levels at 30-34 weeks' gestation (P < .001). Serum proEPIL levels were found elevated in women with intrauterine growth restriction (107.4 +/- 12.99 ng/mL), preeclampsia (104.8 +/- 36.20 ng/mL), or preterm labor (183.8 +/- 36.42 ng/mL) in comparison with levels observed in healthy pregnant women (P < .001). CONCLUSION: These results showed that proEPIL secretion increases in the last trimester during normal pregnancy and is highly secreted in women with pathologic conditions.

Use of a progestogen only preparation containing desogestrel in the treatment of recurrent pelvic pain after conservative surgery for endometriosis.

OBJECTIVE: To assess the effect of a new progestin progestogen only pill (desogestrel) versus an oral contraceptive in the treatment of recurrent endometriosis. STUDY DESIGN: A randomized prospective clinical study. A group of women with endometriosis (n=40) who showed recurrent dysmenorrhea and/or pelvic pain after conservative surgery, and did not desire a pregnancy. Continuous treatment for 6 months with desogestrel (75 microg/d) (n=20) versus a combined oral contraceptive (ethinyl estradiol 20 microg plus desogestrel 150 microg) (n=20) was performed. RESULTS: A significant improvement of both pelvic pain and dysmenorrhea was observed following each type of treatment (P<0.001). The use of desogestrel progestogen only pill was associated with a breakthrough bleeding in 20% patients, while a significant body weight increase was observed in 15% after oral contraceptive. CONCLUSIONS: Both desogestrel and an oral estro-progestinic were effective, safe and low cost therapy of pain symptoms after endoscopic surgery for endometriosis, the former showing an impact on breakthrough bleeding, the later an incidence on body weight increase.