Effects of Delayed Processing in the Specimens Referred to the Testing Laboratory from the Remote Clinics: Impact Analysis of Cost and Patient Care

Background: Responding to the shortcomings in healthcare funding with an ever increasing demand. The National Health Laboratory Services (NHLS) in South Africa implemented a rationalised consolidation of laboratory services, which resulted in the remote clinics referring specimens to the centralised testing laboratory in the city. Clinics serving chronic disease patients were the most affected due to their high patient numbers, and the impact of test results issued had on medical decisions. This study investigated the impact of logistical delays and also the cost of repeat testing and their effects on patient care.

Methods: A prospective pilot study was performed with thirty-one patients recruited from a local clinic which was 14km away from the referral laboratory with the requests of: serum potassium (K+), Alanine Aminotransferase (ALT), and creatinine (CRT). Three specimens were taken from each patient for the study. The first specimen served as a control (no delay in serum separation). The remaining two samples were intentionally delayed for 24 and 48 hours before separation. All specimens were batched and analysed together to avoid inter-run variation. The results of the control and delayed samples were then compared for their critical differences, i.e. the impact on the patient’s management and the estimation of the cost of repeat testing.

Results: Falsely high levels of serum K+ and CRT as well as falsely low ALT levels were noted in both the 24 and 48 hour delayed samples. Significant increases were seen in 96% of the K+ results, 32.25% of the CRT results at 48 hours. A decrease of ALT levels was seen in 3.3%, which were beyond the reference change values (RCV) of each analyte, which could affect clinical decisions.  

Conclusion: The delay in serum separation leads to erroneous results in serum K+, ALT and CRT levels with the following possible consequences:   1) repeat testing or the withdrawal of a fresh sample and retesting;   2) additional tests to confirm the abnormal test;   3) wrong medical decision/s; and         4) a delay in medical decision/s.   The findings revealed the hidden cost incurred by the laboratory, the clinic and the patient, as well as highlighting the impact on overall patient care.