Common causes of EID sample rejection in Zimbabwe and how to mitigate them

Abstract

Early infant diagnosis (EID) of HIV provides an opportunity for early HIV detection and access to appropriate Antiretroviral treatment (ART). Dried Blood Spot (DBS) samples are used for EID of exposed infants, born to HIV-positive mothers. However, DBS rejection rates in Zimbabwe have been exceeding the target of less than 2% per month set by the National Microbiology Reference Laboratory (NMRL), in Harare. The aim of this study was to determine the DBS sample rejection rate, the reasons for rejection and the possible associations between rejection and level of health facility where the samples were collected. This is an analytical cross-sectional study using routine DBS sample data from the NMRL in Harare, Zimbabwe, between January and December 2017.A total of 34 950 DBS samples were received at the NMRL. Of these, 1291(4%) were rejected. Reasons for rejection were insufficient specimen volume (72%), missing request form (11%), missing sample (6%), cross-contamination (6%), mismatch of information (4%) and clotted sample (1%). Samples collected from clinics/rural health facilities were five times more likely to be rejected compared to those from a central hospital. Rejection rates were above the set target of <2%. The reasons for rejection were ‘pre-analytical’ errors including labelling errors, missing or inconsistent data, and insufficient blood collected. Samples collected at primary healthcare facilities had higher rejection rates.

Determining the rate and reasons for specimen rejection among specimens referred for HIV viral load determination through referral linkage to Debre Tabor Comprehensive Specialized Hospital, north-central, Ethiopia,2023: Retrospective study

“…The second type of preanalytical error in this study was referring to an uncentrifuged specimen, which accounted for 20.4 % of the total errors. This finding is nearly identical to the result of a study done in Nepal, which found that 20 % of specimens were rejected due to not being centrifuged on a timely base [ 16 ]. This result, however, is lower than the study conducted at the Amhara Public Health Institute in Bahir Dar, Ethiopia, at 46.9 % [ 9 ].…”

“…Of the total specimens collected the overall specimen rejection rate found in the current study is similar to the overall specimen rejection rates obtained from studies done at the University of Gondar Hospital, Northwest Ethiopia, 3.8 % [ 15 ]; in Zimbabwe, 4 % [ 16 ], and Nepal, 5.5 % [ 17 ]. However, the overall sample rejection at the pre-analytical phase in the current study is higher than the studies conducted at Amhara Public Health Institute in Bahir Dar, Ethiopia, 0.5 % [ 9 ]; St. Paul's Hospital Millennium Medical College in Addis Ababa, Ethiopia, 1.4 % [ 1 ]; Delhi, 1.52 % [ 18 ]; Cantonal Hospital Zenica, 1.7 % [ 19 ]; and Makkah, Saudi Arabia, 1.3 % [ 20 ].…”

“…This result is higher than the study conducted at Chatrapati Shivaji Hospital, 0.09 % [ 24 ]. However, this finding is lower than the result of the study done at the Amhara Public Health Institute in Bahir Dar, Ethiopia, which found that 19.8 % [ 9 ]; Oromia, Ethiopia, 11 % [ 25 ]; Nepal, 20 % [ 16 ]; Turkey, 17.89 % [ 26 ]; India, 18.92 % [ 4 ]; and Bosnia and Herzegovina, 48.50 % [ 19 ] samples were rejected due to hemolysis. This could be due to a lack of standard operating procedures for preventing, detecting, analyzing, and reporting hemolysis.…”

Instructions for COVID-19 self-tests

“…Common user errors with self-test kits include errors in positioning the sampling devices for the test, carrying out the steps in the right order, following the test times correctly, errors in interpreting the results (Seidahmed et al 2008), and users failing to refer to the instructions altogether (Weinhold et al 2018). Other common errors are errors in transferring a set volume of test sample (Incardona et al 2018), and collecting insufficient sample volume, which results in blood spot samples being rejected (Govender et al 2016, Chiku et al 2019. The clarity of user instructions for self-administered tests becomes even more crucial when we consider that tests need to work across cultures and with patients of varying reading ability.…”