Accuracy of a real-time continuous glucose monitoring system in children with septic shock: A pilot study.

AIMS: The aim of this prospective, observational study was to determine the accuracy of a real-time continuous glucose monitoring system (CGMS) in children with septic shock. SUBJECTS AND METHODS: Children aged 30 days to 18 years admitted to the Pediatric Intensive Care Unit with septic shock were included. A real-time CGMS sensor was used to obtain interstitial glucose readings. CGMS readings were compared statistically with simultaneous laboratory blood glucose (BG). RESULTS: Nineteen children were included, and 235 pairs of BG-CGMS readings were obtained. BG and CGMS had a correlation coefficient of 0.61 (P < 0.001) and a median relative absolute difference of 17.29%. On Clarke's error grid analysis, 222 (94.5%) readings were in the clinically acceptable zones (A and B). When BG was < 70, 70-180, and > 180 mg/dL, 44%, 100%, and 76.9% readings were in zones A and B, respectively (P < 0.001). The accuracy of CGMS was not affected by the presence of edema, acidosis, vasopressors, steroids, or renal replacement therapy. On receiver operating characteristics curve analysis, a CGMS reading <97 mg/dL predicted hypoglycemia (sensitivity 85.2%, specificity 75%, area under the curve [AUC] =0.85). A reading > 141 mg/dL predicted hyperglycemia (sensitivity 84.6%, specificity 89.6%, AUC = 0.87). CONCLUSION: CGMS provides a fairly, accurate estimate of BG in children with septic shock. It is unaffected by a variety of clinical variables. The accuracy over extremes of blood sugar may be a concern. We recommend larger studies to evaluate its use for the early detection of hypoglycemia and hyperglycemia.

CD200-CD200R signaling suppresses anti-tumor responses independently of CD200 expression on the tumor.

Expression of CD200, the gene encoding the ligand for the inhibitory immune receptor CD200R, is an independent prognostic factor for various forms of leukemia predicting worse overall survival of the patients. The enhanced expression of CD200 on the tumors implies that anti-tumor responses can be enhanced by blockage of the CD200-CD200R interaction. Indeed, antibody-mediated blockade of the CD200-CD200R inhibitory axis is currently evaluated in clinical tests to boost immune responses against CD200-expressing tumors. Here, we show that mice lacking CD200, the exclusive ligand for CD200R, are resistant to chemical skin carcinogenesis. Importantly, CD200R controls tumor outgrowth independently of CD200 expression by the tumor cells themselves. Furthermore, Cd200(-/-) mice do not become tolerant to intranasally administered antigens, suggesting that tumor rejection is normally suppressed through CD200-induced immune tolerance. Decreased tumor outgrowth is accompanied by increased expression of the proinflammatory cytokines interleukin (IL)-1ß and IL-6 by the lymph node (LN) dendritic cells. During carcinogenesis, skin-draining LNs of Cd200(-/-) mice contain increased numbers of IL-17-producing FoxP3(+) cells, which preferentially home to the tumors. Thus, the CD200-CD200R axis induces tolerance to external and tumor antigens and influences the T-regulatory/Th17 cell ratio. We demonstrate for the first time that the absence of CD200R signaling inhibits outgrowth of an endogenous tumor irrespective of CD200 expression by the tumor cells. This important paradigm shift leads to a much broader applicability of CD200-blockade in the treatment of tumors.

Comparison of bedside and laboratory blood glucose estimations in critically ill children with shock.

OBJECTIVES: Bedside glucometers are often used for frequent glucose measurements on capillary blood in critically ill children. However, there are concerns that capillary blood glucose estimations may not be accurate in children with shock and peripheral edema. The objective of this study was to compare simultaneously obtained laboratory values of arterial or central venous blood glucose with capillary blood glucose estimation using a glucometer in children with shock. DESIGN: Prospective observational study. SETTING: Tertiary pediatric intensive care unit in a children's hospital in Chennai. PATIENTS: All children admitted between July 2007 and September 2008 with shock as defined by the American College of Critical Care Medicine criteria were eligible for inclusion. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Three hundred thirty-seven sets of simultaneous measurements were obtained from 52 children (age range, 3 months to 18 yrs; average Pediatric Risk of Mortality III score 9.6). The mean blood glucose measurement using capillary blood on a bedside glucometer was 135 ± 67 mg/dL (7.5 ± 3.7 mmol/L). The mean laboratory glucose was 130 ± 67 mg/dL (7.2 ± 3.7 mmol/L). The correlation coefficient between the measurements was 0.94. There were no differences between those with and without peripheral edema. Using Bland-Altman plots, the mean difference between capillary samples vs. laboratory glucose was 6 mg/dL (0.3 mmol/L). The spread was wider at the higher ends of blood glucose values. CONCLUSION: Capillary blood glucose estimation in children with shock was similar to the laboratory measurement in the midranges of glucose values.