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Objectives Blood culture is one of the most important tests performed in clinical microbiology laboratories. However, blood culture contamination remains a problematic cause of diagnostic errors for laboratory diagnosis and patient management. This aim of this study was to determine blood culture contamination rates and tendency at Westchester Medical Center (WMC), a tertiary teaching hospital in suburban New York City. Methods All blood culture tests at WMC received from January 2017 to December 2018, as well as some historical data from 2007 to 2014, were retrospectively retrieved. Blood culture contamination rates were determined according to the laboratory’s predefined criteria. Results From 2007 to 2014, a total of 209,750 blood cultures were performed with an average contamination rate of 1.6% (ranging from 0.4% to 3.5% monthly). The total numbers of blood cultures performed in 2017 and 2018 were 27,863 and 28,047, respectively. The overall positive rate of blood culture was 6.8% in 2017 and 7.6% in 2018. The contamination rate of blood culture was 0.6% in 2017 and 0.9% in 2018 with very few variations among different months of the year, which was significantly lower than that of the national benchmark (~2.5%) on blood culture contamination. The majority of contaminants were Staphylococcus epidermidis, accounting for 87% of source contamination, followed by Corynebacterium species (5.5%), Bacillus species and Micrococcus species (3.5% each), and Propionibacterium species (0.5%). Conclusion Adherence to current guideline on appropriate blood collection techniques and monthly monitoring and timely feedback to phlebotomists should be continued to keep a low contamination rate for blood culture, which is not only from the perspective of individual patient care but also from the standpoint of hospital epidemiology and public health.

Objectives: Renal cell carcinoma (RCC) is a heterogeneous neoplasm with different morphology and molecular changes. Recently, a study investigated panmetabolomic profiles and metabolic genes of more than 600 clear cell RCC (ccRCC) tumors showed the rate-limiting gluconeogenic enzyme fructose-1,6-bisphosphatase 1 (FBP-1) was inhibited in almost 100% of ccRCCs. Here, we …

To study the comparative value of the levels of cardiac troponin I (cTnI), creatine kinase-MB isoenzyme (CK-MB), and myoglobin in the detection of acute ischemic myocardial injury, we serially measured plasma concentrations of these cardiac proteins in 12 pigs with myocardial ischemia subtending severe coronary artery stenoses and in 5 pigs with a sham operation performed, but without coronary artery stenosis. In the stenosis group, flow in the left anterior descending (LAD) artery was reduced by 36% and maintained for 24 hours (n = 3), 7 days (n = 6), or 4 weeks (n = 3). Flow in the coronary artery was measured by a flowmeter, and regional left ventricular dysfunction was monitored by echocardiography. Myocardial infarction was identified with triphenyltetrazolium chloride staining. All pigs with stenosis of the LAD had significant ultrastructural abnormalities consisting of loss of myofibrils and an increase in mitochondria and glycogen deposition. Cardiac proteins were released in all pigs with stenosis of the LAD artery during the development of myocardial ischemia; the levels of cTnI, CK-MB, and myoglobin increased significantly relative to the baseline. The sensitivity and specificity for cTnI were higher than for CK-MB or myoglobin. Results of this study show that cTnI is the better marker for the detection of acute ischemic myocardial injury. Increased levels of cTnI can be found in reversible and irreversible myocardial ischemic injury in this model.