Lawrie Denise, Payne Helen, Nieuwoudt Martin, Glencross Deborah Kim
Department of Molecular Medicine and Haematology, National Health Laboratory Service and Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
S Afr Med J. 2015 Sep 21;105(7):589-95. doi: 10.7196/SAMJnew.7914.
The paediatric full blood count and lymphocyte subset reference intervals used by the National Health Laboratory Service (NHLS), South Africa (SA), are taken from two international reference interval publications. Differences in reference intervals suggest that international data sets may not be appropriate for use in SA.
To study immunohaematological values of a group of clinically healthy children from an informal settlement in Cape Town, SA, to assess whether international paediatric reference intervals used by the NHLS are appropriate.
A cross-sectional study of 207 female and 174 male HIV-uninfected children living in an informal settlement in Cape Town was performed. Full blood counts, automated differential counts and lymphocyte subset analysis were done using internationally accepted technologies. Data were categorised by age and reference intervals compiled using medians and 95% confidence intervals (CIs). Gender comparisons were calculated by non-parametric tests.
Although median and 95% CI values differed slightly, physiological trends for red cell, platelet, white blood cell differential and lymphocyte subsets were similar to international reference intervals currently in use at the NHLS. Benign ethnic neutropenia was not a significant finding, and gender-specific intervals were not necessary until 12 years of age. Lower overall median values for haemoglobin and haematocrit, and higher median values for mean cell volume and red cell distribution width, were noted. Assessment of haemoglobin, red cell distribution width and calculated Mentzer ratios suggested underlying iron deficiency in 14.2% of participants.
Paediatric immunohaematological reference intervals observed in this study are similar to, and support continued use of, international paediatric reference intervals. Underlying iron and related nutritional deficiencies may be contributing to lower haemoglobin levels noted in local children. A larger nationwide study, including all ethnic groups, is recommended.
南非国家卫生实验室服务局（NHLS）所采用的儿科全血细胞计数和淋巴细胞亚群参考区间取自两份国际参考区间出版物。参考区间的差异表明国际数据集可能不适用于南非。
研究南非开普敦一个非正式定居点的一组临床健康儿童的免疫血液学值，以评估NHLS使用的国际儿科参考区间是否合适。
对居住在开普敦一个非正式定居点的207名未感染艾滋病毒的女童和174名男童进行了横断面研究。使用国际公认的技术进行全血细胞计数、自动分类计数和淋巴细胞亚群分析。数据按年龄分类，并使用中位数和95%置信区间（CI）编制参考区间。通过非参数检验进行性别比较。
尽管中位数和95%CI值略有不同，但红细胞、血小板、白细胞分类和淋巴细胞亚群的生理趋势与NHLS目前使用的国际参考区间相似。良性种族性中性粒细胞减少症并非显著发现，在12岁之前无需设定特定性别的区间。血红蛋白和血细胞比容的总体中位数较低，平均红细胞体积和红细胞分布宽度的中位数较高。对血红蛋白、红细胞分布宽度和计算得出的门泽尔比率的评估表明，14.2%的参与者存在潜在的缺铁情况。
本研究中观察到的儿科免疫血液学参考区间与国际儿科参考区间相似，并支持继续使用。潜在的铁及相关营养缺乏可能导致当地儿童血红蛋白水平较低。建议开展一项更大规模的全国性研究，纳入所有种族群体。
