New methods for quantification of amoxicillin and clindamycin in human plasma using HPLC with UV detection

OBJECTIVES: We aimed to develop simple and rapid HPLC methods for determination of amoxicillin and clindamycin in human plasma. METHODS: Plasma samples were pretreated by direct deproteinization with acetonitrile and the analytical separation took place on a reverse phase Poroshell 120 EC-C18 column (2.7 μm, 2.1 × 100 mm) with a gradient of acetonitrile. UV detection at 229 nm for amoxicillin and 204 nm for clindamycin was used for determination of the antibiotics in plasma. RESULTS: The calibration curves were linear over the concentration ranges of 1–100 mg/L for amoxicillin and 1–15 mg/L for clindamycin with a correlation coefficient of ≥0.98. Intra-assay precisions were all ≤15% and the accuracies were within ±15%. The limit of quantification (LOQ) was found to be 0.5 mg/L for amoxicillin and 1 mg/L for clindamycin with inter-assay imprecision coefficient of variances (CVs) of 18.7% and 15.6%, respectively. The present HPLC methods were successfully applied on spike-in samples and on plasma samples collected 4–6 and 3.5–5.5 h after oral antibiotic administration of 500 mg of amoxicillin and 600 mg of clindamycin, respectively. CONCLUSIONS: We have developed HPLC methods with UV detection for quantification of amoxicillin and clindamycin in human plasma. The methods are fast, simple and suitable for use in routine settings and clinical studies

Temporal changes in cardiovascular disease and infections in dialysis across a 22-year period:a nationwide study

Abstract Background Cardiovascular diseases (CVD) and infections are recognized as serious complications in patients with end stage kidney disease. However, little is known about the change over time in incidence of these complications. This study aimed to investigate temporal changes in CVD and infective diseases across more than two decades in chronic dialysis patients. Methods All patients that initiated peritoneal dialysis (PD) or hemodialysis (HD) between 1996 and 2017 were identified and followed until outcome (CVD, pneumonia, infective endocarditis (IE) or sepsis), recovery of kidney function, end of dialysis treatment, death or end of study (December 31st, 2017). The calendar time was divided into 5 periods with period 1 (1996–2000) being the reference period. Adjusted rate ratios were assessed using Poisson regression. Results In 4285 patients with PD (63.7% males) the median age increased across the calendar periods from 65 [57–73] in 1996–2000 to 69 [55–76] in 2014–2017, (p <  0.0001). In 9952 patients with HD (69.2% males), the overall median age was 71 [61–78] without any changes over time. Among PD, an overall non-significant decreasing trend in rate ratios (RR) of CVD was found, (p = 0,071). RR of pneumonia increased significantly throughout the calendar with an almost two-fold increase of the RR in 2014–2017 (RR 1.71; 95% CI 1.46–2.0), (p <  0.001), as compared to the reference period. The RR of IE decreased significantly until 2009 (RR 0.43; 95% CI 0.21–0.87), followed by a return to the reference level in 2010–2013 (RR 0.87; 95% CI 0.47–1.60 and 2014–2017 (RR 1.1; 95% CI 0.59–2.04). A highly significant (p <  0.001) increase in sepsis was revealed across the calendar periods with an almost 5-fold increase in 2014–2017 (RR 4.69 95% CI 3.69–5.96). In HD, the RR of CVD decreased significantly (p <  0.001) from 2006 to 2017 (RR 0.85; 95% CI 0.79–0.92). Compared to the reference period, the RR for pneumonia was high during all calendar periods (p <  0.05). The RR of IE was initially unchanged (p = 0.4) but increased in 2010–2013 (RR 2.02; 95% CI 1.43–2.85) and 2014–2017 (RR 3.39; 95% CI 2.42–4.75). No significant changes in sepsis were seen. Conclusion Across the two last decades the RR of CVD has shown a decreasing trend in HD and PD patients, while RR of pneumonia increased significantly, both in PD and in HD. Temporal trends of IE in HD, and particularly of sepsis in PD were upwards across the last decades

Proposal for the use of echocardiography in bloodstream infections due to different streptococcal species

BACKGROUND: Infective endocarditis (IE) is diagnosed in 7–8% of streptococcal bloodstream infections (BSIs), yet it is unclear when to perform transthoracic (TTE) and transoesophageal echocardiography (TOE) according to different streptococcal species. The aim of this sub-study was to propose a flowchart for the use of echocardiography in streptococcal BSIs. METHODS: In a population-based setup, we investigated all patients admitted with streptococcal BSIs and crosslinked data with nationwide registries to identify comorbidities and concomitant hospitalization with IE. Streptococcal species were divided in four groups based on the crude risk of being diagnosed with IE (low-risk  30%). Based on number of positive blood culture (BC) bottles and IE risk factors (prosthetic valve, previous IE, native valve disease, and cardiac device), we further stratified cases according to probability of concomitant IE diagnosis to create a flowchart suggesting TTE plus TOE (IE > 10%), TTE (IE 3–10%), or “wait & see” (IE < 3%). RESULTS: We included 6393 cases with streptococcal BSIs (mean age 68.1 years [SD 16.2], 52.8% men). BSIs with low-risk streptococci (S. pneumoniae, S. pyogenes, S. intermedius) are not initially recommended echocardiography, unless they have ≥3 positive BC bottles and an IE risk factor. Moderate-risk streptococci (S. agalactiae, S. anginosus, S. constellatus, S. dysgalactiae, S. salivarius, S. thermophilus) are guided to “wait & see” strategy if they neither have a risk factor nor ≥3 positive BC bottles, while a TTE is recommended if they have either ≥3 positive BC bottles or a risk factor. Further, a TTE and TOE are recommended if they present with both. High-risk streptococci (S. mitis/oralis, S. parasanguinis, G. adiacens) are directed to a TTE if they neither have a risk factor nor ≥3 positive BC bottles, but to TTE and TOE if they have either ≥3 positive BC bottles or a risk factor. Very high-risk streptococci (S. gordonii, S. gallolyticus, S. mutans, S. sanguinis) are guided directly to TTE and TOE due to a high baseline IE prevalence. CONCLUSION: In addition to the clinical picture, this flowchart based on streptococcal species, number of positive blood culture bottles, and risk factors, can help guide the use of echocardiography in streptococcal bloodstream infections. Since echocardiography results are not available the findings should be confirmed prospectively with the use of systematic echocardiography. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12879-021-06391-2

Hemodynamic monitoring by intracardiac impedance measured by cardiac resynchronization defibrillators:Evaluation in a controlled clinical setting (BIO.Detect HF II study)

Background: In patients with cardiac resynchronization therapy defibrillators (CRT-Ds), intracardiac impedance measured by dedicated CRT-D software may be used to monitor hemodynamic changes. We investigated the relationship of hemodynamic parameters assessed by intracardiac impedance and by echocardiography in a controlled clinical setting. Methods: The study enrolled 68 patients (mean age, 66 ± 9 years; 74% males) at 12 investigational sites. The patients had an indication for CRT-D implantation, New York Heart Association class II/III symptoms, left ventricular ejection fraction 15%–35%, and a QRS duration ≥150 ms. Two months after a CRT-D implantation, hemodynamic changes were provoked by overdrive pacing. Intracardiac impedance was recorded at rest and at four pacing rates ranging from 10 to 40 beats/min above the resting rate. In parallel, echocardiography measurements were performed. We hypothesized that a mean intra-individual correlation coefficient (rmean) between stroke impedance (difference between end-systolic and end-diastolic intracardiac impedance) measured by CRT-D and the aortic velocity time integral (i.e., stroke volume) determined by echocardiography would be significantly larger than 0.65. Results: The hypothesis was evaluated in 40 patients with complete data sets. The rmean was 0.797, with a lower confidence interval bound of 0.709. The study hypothesis was met (p = 0.007). A stepwise reduction of stroke impedance and stroke volume was observed with increasing heart rate. Conclusions: Intracardiac impedance measured by implanted CRT-Ds correlated well with the aortic velocity time integral (stroke volume) determined by echocardiography. The impedance measurements bear potential and are readily available technically, not requiring implantation of additional material beyond standard CRT-D system