ABSTRACT
BACKGROUND: Reference intervals are important for interpretation of clinical laboratory tests. The platelet (PLT) indices such as the mean platelet volume (MPV) and platelet distribution width (PDW) are newer hematological parameters, which have been recently reported as clinically valuable biomarkers. However, there are not many studies that have estimated the reference intervals for these parameters in healthy Chinese Han adults. OBJECTIVE: The objectives of this study were to establish reference values of PLT indices [including PLT count, MPV, PDW, platelet-large cell ratio (P-LCR), and plateletcrit (Pct)] for healthy Chinese Han adults. We also aimed to determine the region-based differences of PLT indices in China. METHODS: A total of 4,642 volunteers with a mean age of 43 were recruited from six regions of China. PLT indices were performed on Sysmex XE-2100 hematology analyzers, whose traceability was well verified. RESULTS: There were significant region-based differences for all PLT indices. Reference people in Chengdu had the lowest mean PLT count and Pct, but the highest MPV, PDW, and P-LCR among the six regions. Therefore, we derived the reference intervals in Chinese Han population excluding Chengdu reference people for PLT indices as PLT count: (127-341) × 10(9)/l; MPV: (9.20-13.30) fl; PDW: 9.90-19.00%; P-LCR: 18.10-52.00%; Pct: 16.00-41.00%. CONCLUSIONS: Region-specific reference intervals are essential as there were statistically significant region-related differences in the PLT parameters. The reference intervals established in this study differed from the existing reference values. Chengdu region may need proper specific reference ranges, which apply to their people, for all PLT parameters.
Subject(s)
Blood Platelets/metabolism , Adult , Age Factors , Aged , Asian People/ethnology , Blood Platelets/cytology , Demography , Female , Hematologic Tests , Humans , Male , Mean Platelet Volume , Middle Aged , Platelet Count/methods , Platelet Count/standards , Reference Values , Reproducibility of Results , Young AdultABSTRACT
Objective To assess the applicability of the Modification of Diet in Renal Disease (MDRD)formula to kidney function impaired Chinese diabetic patients.Methods Glomerular filtration rates(GFRs)in 463 Chinese diabetic patients(219 female,244 male,aged 14 to 88)were estimated by measuring ~(99m)Tc-DTPA clearance and with equations based on serum creatinine(Scr)and cystatin C(Cys C)concentrations.GFRs derived from various equations were compared with the ~(99m)Tc-DTPA clearance GFRs and their relative accuracies were assessed with ROC analysis.All the Scr measurements were performed with both the Roche enzymatic assay and the Beckman LX20 kinetic alkaline picrate assay,and Cys C with immunonephelometric and immunoturbidimetric assays.Results The reciprocals of Cys C and Scr were linearly correlated with ~(99m)Tc-DTPA clearance GFRs(r=0.830 and 0.690,repectively).The correlation of GFR with Scr could be expressed by an adjusted MDRD equation:GFR [ ml?(min?1.73 m~2)~(-1)]=175?(Scr)~(-1.154)?(age)~(-0.203)?0.742(female)?0.827,where 0.827 was a coefficient for Chinese.The adjusted equation showed a better accuracy than the MDRD equation(areas under the ROC curve 0.818 vs 0.644).The adjusted equation was also more accurate than equations obtained in previous Chinese studies.GFRs were also estimated by using Cys(in mg/L)with the following equation:GFR [ ml?(min?1.73 m~2)~(-1)] = 63.24?(Cys C)~(-0.3378).The accuracy of the Cys equation was similar to the Scr equation,or better in patients aged 60 and above.The Roche enzymatic results which were traceable to the isotope dilution mass spectrometry(IDMS)methods were significantly lower than Beckman LX20 results,but the results were closely correlated with each other(Y = 0.94X-0.02).When non-traceable Scr results were used,the coefficient needed to be adjusted.Conclusions GFRs can be estimated with equations based on either Scr or Cys C.GFR estimation should use standardized Scr results and take into account ethnic effects.
