Evaluation of a Portable Haemoglobin Metre Performance in Children with Sickle Cell Disease and Implications for Healthcare in Resource-poor Settings.

BACKGROUND

Sub-Saharan Africa has the largest burden and worst outcome of sickle cell disease (SCD). This gloomy outlook has been attributed to the lack of use of simple and cost-effective measures for diagnosis and treatment of the disease. Although haematology analysers are the gold standard for accurate measurement of haemoglobin (Hb) concentration, they are often out of reach of most health facilities in resource-poor settings, thus creating a care gap. We conducted this study to examine the agreement between a point-of-care device and haematology analyser for determining the Hb concentration in children with SCD and its usefulness in resource-poor settings.

METHODS

Ethylenediaminetetraacetic acid blood samples collected from participants were processed to estimate their Hb concentration using two devices (Sysmex KX21N haematology analyser and portable mission Hb device). The agreement between the two sets of measurements was assessed by the Bland and Altman method.

RESULTS

The intraclass and concordance correlation coefficients were 0.854 and 0.936, respectively. Sensitivity and specificity were 84.2% and 98.6%, respectively. The positive and negative predictive values were 94.1% and 96.0%, respectively. The Bland and Altman's limit of agreement was -2.3 to 1.6 and the mean difference was -0.34 with non-significant variability between the two measurements (p  =  0.949).

CONCLUSION

Hb concentration determined by the portable testing system is comparable with that determined by the haematology analyser. We recommend its use as a point-of-care device for determining Hb concentration of SCD children in resource-poor settings where haematology analysers are not available.