In vitro efficacy of daptomycin and teicoplanin combined with ethanol, clarithromycin or gentamicin as catheter lock solutions.

BACKGROUND: Despite widespread use, optimum choice of antimicrobial agents, concentrations, combinations and exposure times have not been determined for antibiotic lock technique (ALT). Our objective was to evaluate the efficacy of different antibiotic combinations using an in vitro model of catheter-related infection. Daptomycin (DAP) 5 mg/mL, teicoplanin (TEC) 5 mg/mL, both alone and combined with gentamicin (GM) 2.5 mg/mL, clarythromycin (CLA) 5 mg/mL or ethanol 35 % were evaluated against four clinical strains of methicillin resistant coagulase negative staphylococci. Lock solutions were renewed every 24 h. RESULTS: After 72 h catheters were reincubated with culture media to investigate bacterial regrowth. All antibiotic combinations resulted in significant reductions (p < 0.05) of Log(10) cfu/mL at 72 h for both organisms compared with controls. DAP resulted in significant reductions of Log(10) for all organism versus TEC (p = 0.001). Only DAP reached the limit of detection at 72 h, however did not prevent regrowth after 24 h of ALT removal. DAP + Ethanol and TEC + ethanol eradicated biofilm at 72 h, but only DAP + ethanol (against all strains) and DAP + CLA (against two strains) prevented regrowth at 24 h after ALT removal. CONCLUSIONS: Based on these data, ALT with DAP + ethanol and DAP + CLA should be explored in clinical trials.

Multicentre evaluation of glycated haemoglobin (HbA1c) of Roche Diagnostics in Andalusia.

BACKGROUND: A Spanish multicentre evaluation of the third generation of Roche Diagnostics immunoturbidimetric inhibition method (TINIA) is presented for quantification of haemoglobin A1c (HbA1c) in whole blood. METHODS: The analytical performance of the TINIA test was evaluated and blood sample results were compared with two other widely used analysers, Bio-Rad Variant II and Adams Arkray HA-8160, based on HPLC. RESULTS: Within- and between-batch imprecision (coefficients of variation (CVs)) for HbA1c levels of 5, 6, 7 and 8% were 0.77, 1.23, 1.35 and 1.26% and 2.38, 1.51, 1.76 and 2.16%, respectively. For low (5.4% A1c) and high (10.1% A1c) quality control samples, the within and between-batch %CV were: 1.26; 1.43 and 2; 1.71 respectively. The test met the expected performance in most aspects, except for linearity, that is under the reported range, and HbF interferences, detected for levels over 7.5%. There was a good concordance between the results of TINIA and Variant-IIt in the whole range and with HA-8160 only up to levels of 9%. Between-batch imprecision suggests more frequent calibrations than reported by the provider to maintain variability within the limits established by clinical practice guidelines. CONCLUSIONS: The assay meets the necessary quality standards for routine use, as long as we keep the analytical variability within narrow limits. The results may be interchangeable with the tested HPLC systems, but HbF interference is not detected and it happens at lower levels than reported.