Pattern of Blood Specimen Rejection at a Nigerian Public Clinical Laboratory

Abstract

Obtaining appropriate blood specimen is central towards provision of reliable results in a clinical laboratory. To ensure that blood specimen collected for analysis reflect the physiologic or pathologic processes they represent, potential sources of pre-analytic errors should be identified and avoided. Our study aimed at determining the pattern of blood specimen rejection in a public clinical laboratory with a view of identifying inadequacies that should be improved upon. The sample rejection register at the Haematology laboratory of Usmanu Danfodiyo University Teaching Hospital Sokoto, Northwest Nigeria was accessed for a two-year period data on number of specimens rejected, reasons for rejection, types of tests for which rejections were made and affected clinical units; and the retrieved data were analysed using Microsoft Excel 2010. Of the 53,955 specimens received during the study period, 122 were rejected giving an overall specimen rejection rate of 0.23%. Incomplete specimen labelling and clotted specimens were the commonest reasons for specimen rejection having accounted for 59.8% (73) and 30.3% (37) of the rejections respectively. Coagulation Screening Tests and Packed Cell Volume had the highest rejection rates of 52.5% (64) and 18.0% (22) respectively. The Accident and Emergency (A&E) and Emergency Paediatric Unit (EPU) recorded the highest rates of sample rejection with 31.1% (37) and 11.8% (14) rejection rates respectively. We concluded that the reasons for blood specimen rejection in our public clinical laboratory could be avoided via the use of appropriate and properly labelled specimen containers and avoidance of faults in specimen collection, storage and transportation to the laboratory.