Tuberculosis Laboratory Diagnosis Quality Assurance among Public Health Facilities in West Amhara Region, Ethiopia

Abstract

IntroductionReliable smear microscopy is an important component of Directly Observed Treatment Scheme (DOTS) strategy for TB control program in countries with limited resources. Despite external quality assessment is established in Ethiopia, there is lower TB detection rate (48%) in Amhara region compared to the World Health Organization (WHO) estimate (70%). This highlights the quality of smear microscopy needs to be evaluated. Therefore, the aim of this study was to assess the quality of sputum smear microscopy performance among health center laboratories in West Amhara region, Ethiopia.Materials and MethodsA cross sectional study was conducted from July 08, 2013 to July 07, 2014. Data were collected from 201 public health center laboratories using a structured questionnaire. Slides were collected based on Lot Quality Assurance Sampling (LQAS) method and rechecked blindly by trained laboratory technologists. The data were entered into EPI info V.7 and smear quality indicators and AFB results were analyzed by SPSS version 20.ResultsAmong 201 laboratories enrolled in this study, 47 (23.4%) laboratories had major errors. Forty one (20.4%) laboratories had a total of 67 false negative and 29 (14.4%) laboratories had a total of 68 false positive results. Specimen quality, smear thickness and evenness were found poor in 134 (66.7%), 133 (66.2%) and 126 (62.7%) laboratories, respectively. Unavailability of microscope lens cleaning solution (AOR: 2.90; 95% CI: 1.25–6.75; P: 0.013) and dirty smears (AOR: 2.65; 95% CI: 1.14–6.18; P: 0.024) were correlated with false negative results whereas no previous EQA participation (AOR: 3.43; 95% CI: 1. 39-8.45; P: 0.007) was associated with false positive results.ConclusionThe performance of health facilities for sputum smear microscopy was relatively poor in West Amhara region. Hence, strengthening the EQA program and technical support on sputum smear microscopy are recommended to ensure quality tuberculosis diagnostic service.

External Quality Assessment of Laboratories Performance in AFB Microscopy in Tigray Region, North Ethiopia 2016

“…This is different from study conducted in Amhara region, Ethiopia which was 83.1% [7]. This difference may be due to geographical difference.…”

“…This finding is higher compared to the 2.9% of diagnostic centers with low SPR (< 5%) and low ANSV (< 301 slides) reported in New Delhi [12]. In contrast it is lower than study conducted in Ethiopia which was 39.8% [7].…”

“…In our finding false positive results was reported in 4.7% laboratories. This is lower than study conducted in Ethiopia Amhara region which was 14.4% [7]. But higher than studies conducted inTanzania, India and Iraq that reported no false positive result [8][9][10].…”

“…This is relatively high compared to other studies conducted in Ethiopia, Amahara region which was 77% [7]. This difference may due method difference because we used three methods (blind rechecking, proficiency testing and onsite evaluation) but they used only blind rechecking.…”

External quality assessment in resource–limited countries

“…They also noted the discrepancy between microscopy centres and district supervisors was higher (4.7%) than with the reference laboratory (1%), suggesting lack of training and motivation at district level ( 45 ). Shiferaw et al noted false negative results during rechecking were associated with unavailability of microscope lens cleaning solution and dirty smears, and false positive results with no previous EQA experience ( 46 ). Shargie et al suggested disagreements during rechecking between regional and national reference readers are likely due to low-positivity of discordant slides ( 47 ).…”