Parker D R, Bargiota A, Cowan F J, Corrall R J
University of Bristol Department of Medicine, Bristol Royal Infirmary, UK.
Clin Endocrinol (Oxf). 1997 Dec;47(6):679-83. doi: 10.1046/j.1365-2265.1997.3061130.x.
The assay of dried blood spots on filter paper to determine blood glucose concentration has been used to detect hypoglycaemia in out patients. We assessed the accuracy of this approach in assaying blood glucose concentrations in the hypoglycaemic range.
Volunteers were rendered hypoglycaemic by intravenous infusion of insulin. The glucose concentration in simultaneously taken blood samples was measured either fresh or after drying on filter paper.
Twenty-four healthy young volunteers and 9 patients with insulin-dependent diabetes were studied.
Plasma glucose concentrations were measured using a standard auto analyser glucose oxidase method. Whole blood taken simultaneously was placed on prepared filter paper and allowed to dry; glucose concentration was then measured using a well-established technique. A correction factor was applied to convert the glucose concentration of plasma to that of whole blood. The relationship between glucose concentrations measured by the two methods was determined by regression coefficient.
In the unequivocally hypoglycaemic range (plasma < or = 2.5 mmol/l), corrected dried blood spot glucose concentrations significantly correlated with standard plasma glucose concentrations (r = 0.81; P < 0.001). The dried blood spot method had a sensitivity of 91%. In the range designated probable hypoglycaemia (plasma < or = 3.3 mmol/l), there was also significant correlation (r = 0.90; P < 0.001) and the sensitivity was 96%. The specificity of the dried blood spot method was 100% in both ranges.
Measurement of glucose concentrations in dried blood spots is specific and sensitive in the hypoglycaemic range. The present study indicates that hypoglycaemia may be excluded or confirmed respectively when levels in excess of 3.7 or below 2.8 mmol/l are found in uncorrected dried blood spot analysis.
采用检测滤纸上干血斑血糖浓度的方法来检测门诊患者的低血糖情况。我们评估了该方法在检测低血糖范围内血糖浓度时的准确性。
通过静脉输注胰岛素使志愿者出现低血糖。对同时采集的血样，一部分新鲜测定血糖浓度，另一部分在滤纸上干燥后测定。
研究了24名健康年轻志愿者和9名胰岛素依赖型糖尿病患者。
采用标准自动分析仪葡萄糖氧化酶法测量血浆葡萄糖浓度。将同时采集的全血置于制备好的滤纸上使其干燥，然后采用成熟技术测量葡萄糖浓度。应用校正因子将血浆葡萄糖浓度换算为全血葡萄糖浓度。通过回归系数确定两种方法测得的葡萄糖浓度之间的关系。
在明确的低血糖范围（血浆≤2.5 mmol/L）内，校正后的干血斑葡萄糖浓度与标准血浆葡萄糖浓度显著相关（r = 0.81；P < 0.001）。干血斑法的灵敏度为91%。在界定为可能低血糖的范围（血浆≤3.3 mmol/L）内，也存在显著相关性（r = 0.90；P < 0.001），灵敏度为96%。干血斑法在两个范围内的特异性均为100%。
在低血糖范围内，测量干血斑中的葡萄糖浓度具有特异性和敏感性。本研究表明，在未校正的干血斑分析中，当发现血糖水平超过3.7 mmol/L或低于2.8 mmol/L时，可分别排除或确诊低血糖。
