Implementation of the laboratory quality management system (ISO 15189): Experience from Bugando Medical Centre Clinical Laboratory – Mwanza, Tanzania

Background: Use of laboratory evidence-based patient health care in Tanzania remains a complex problem, as with many other countries in sub-Saharan Africa. As at 2010, 39 African countries, including Tanzania, had no clinical laboratories that met the minimum requirements for international laboratory standards (International Organization for Standardization [ISO] 15189).   Objective: The aim of this article is to share experience from Bugando Medical Centre laboratory’s milestones in reaching ISO 15189 accreditation.   Methods: Mentors to address the laboratory management and technical requirements performed a gap analysis using the Southern African Development Community Accreditation system checklist. Several non-conformances were detected. System and technical procedures were developed, approved and communicated. Quality indicators were established to measure laboratory improvement and to identify issues which require immediate and preventive actions.   Results: The departments’ external quality assessment performance increased after ISO 15189 implementation (e.g. Parasitology from 45% to 100%, Molecular Biology from no records to 100%, Biochemistry 50% to 95%, Tuberculosis Microscopy 60% to 100%, and Microbiology from 48.1% to 100%). There was a reduction in complaints, from eight to two per week. Rejected samples were reduced from 7.2% to 1.2%. Turn-around time was not recorded before implementation but reached 92% (1644/1786) of the defined targets, and the proportion of contamination in blood cultures decreased from 16% to 4%.   Conclusion: Our experience suggests that the implementation of a quality management system is possible in resource-limited countries like Tanzania. Mentorship is necessary and should be done by professional laboratory mentors trained in quality management systems. Financial resources and motivated staff are key to achieving ISO 15189 accreditation

Evaluation of simple rapid HIV assays and development of national rapid HIV test algorithms in Dar es Salaam, Tanzania

BACKGROUND: Suitable algorithms based on a combination of two or more simple rapid HIV assays have been shown to have a diagnostic accuracy comparable to double enzyme-linked immunosorbent assay (ELISA) or double ELISA with Western Blot strategies. The aims of this study were to evaluate the performance of five simple rapid HIV assays using whole blood samples from HIV-infected patients, pregnant women, voluntary counseling and testing attendees and blood donors, and to formulate an alternative confirmatory strategy based on rapid HIV testing algorithms suitable for use in Tanzania. METHODS: Five rapid HIV assays: Determine HIV-1/2 (Inverness Medical), SD Bioline HIV 1/2 3.0 (Standard Diagnostics Inc.), First Response HIV Card 1-2.0 (PMC Medical India Pvt Ltd), HIV1/2 Stat-Pak Dipstick (Chembio Diagnostic System, Inc) and Uni-Gold HIV-1/2 (Trinity Biotech) were evaluated between June and September 2006 using 1433 whole blood samples from hospital patients, pregnant women, voluntary counseling and testing attendees and blood donors. All samples that were reactive on all or any of the five rapid assays and 10% of non-reactive samples were tested on a confirmatory Inno-Lia HIV I/II immunoblot assay (Immunogenetics). RESULTS: Three hundred and ninety samples were confirmed HIV-1 antibody positive, while 1043 were HIV negative. The sensitivity at initial testing of Determine, SD Bioline and Uni-Gold was 100% (95% CI; 99.1-100) while First Response and Stat-Pak had sensitivity of 99.5% (95% CI; 98.2-99.9) and 97.7% (95% CI; 95.7-98.9), respectively, which increased to 100% (95% CI; 99.1-100) on repeat testing. The initial specificity of the Uni-Gold assay was 100% (95% CI; 99.6-100) while specificities were 99.6% (95% CI; 99-99.9), 99.4% (95% CI; 98.8-99.7), 99.6% (95% CI; 99-99.9) and 99.8% (95% CI; 99.3-99.9) for Determine, SD Bioline, First Response and Stat-Pak assays, respectively. There was no any sample which was concordantly false positive in Uni-Gold, Determine and SD Bioline assays. CONCLUSION: An alternative confirmatory HIV testing strategy based on initial testing on either SD Bioline or Determine assays followed by testing of reactive samples on the Determine or SD Bioline gave 100% sensitivity (95% CI; 99.1-100) and 100% specificity (95% CI; 96-99.1) with Uni-Gold as tiebreaker for discordant results

Introducing a multi-site program for early diagnosis of HIV infection among HIV-exposed infants in Tanzania

<p>Abstract</p> <p>Background</p> <p>In Tanzania, less than a third of HIV infected children estimated to be in need of antiretroviral therapy (ART) are receiving it. In this setting where other infections and malnutrition mimic signs and symptoms of AIDS, early diagnosis of HIV among HIV-exposed infants without specialized virologic testing can be a complex process. We aimed to introduce an Early Infant Diagnosis (EID) pilot program using HIV DNA Polymerase Chain Reaction (PCR) testing with the intent of making EID nationally available based on lessons learned in the first 6 months of implementation.</p> <p>Methods</p> <p>In September 2006, a molecular biology laboratory at Bugando Medical Center was established in order to perform HIV DNA PCR testing using Dried Blood Spots (DBS). Ninety- six health workers from 4 health facilities were trained in the identification and care of HIV-exposed infants, HIV testing algorithms and collection of DBS samples. Paper-based tracking systems for monitoring the program that fed into a simple electronic database were introduced at the sites and in the laboratory. Time from birth to first HIV DNA PCR testing and to receipt of test results were assessed using Kaplan-Meier curves.</p> <p>Results</p> <p>From October 2006 to March 2007, 510 HIV-exposed infants were identified from the 4 health facilities. Of these, 441(87%) infants had an HIV DNA PCR test at a median age of 4 months (IQR 1 to 8 months) and 75(17%) were PCR positive. Parents/guardians for a total of 242(55%) HIV-exposed infants returned to receive PCR test results, including 51/75 (68%) of those PCR positive, 187/361 (52%) of the PCR negative, and 4/5 (80%) of those with indeterminate PCR results. The median time between blood draw for PCR testing and receipt of test results by the parent or guardian was 5 weeks (range <1 week to 14 weeks) among children who tested PCR positive and 10 weeks (range <1 week to 21 weeks) for those that tested PCR negative.</p> <p>Conclusions</p> <p>The EID pilot program successfully introduced systems for identification of HIV-exposed infants. There was a high response as hundreds of HIV-exposed infants were registered and tested in a 6 month period. Challenges included the large proportion of parents not returning for PCR test results. Experience from the pilot phase has informed the national roll-out of the EID program currently underway in Tanzania.</p

Evaluation of simple rapid HIV assays and development of national rapid HIV test algorithms in Dar es Salaam, Tanzania

Abstract Background Suitable algorithms based on a combination of two or more simple rapid HIV assays have been shown to have a diagnostic accuracy comparable to double enzyme-linked immunosorbent assay (ELISA) or double ELISA with Western Blot strategies. The aims of this study were to evaluate the performance of five simple rapid HIV assays using whole blood samples from HIV-infected patients, pregnant women, voluntary counseling and testing attendees and blood donors, and to formulate an alternative confirmatory strategy based on rapid HIV testing algorithms suitable for use in Tanzania. Methods Five rapid HIV assays: Determine™ HIV-1/2 (Inverness Medical), SD Bioline HIV 1/2 3.0 (Standard Diagnostics Inc.), First Response HIV Card 1–2.0 (PMC Medical India Pvt Ltd), HIV1/2 Stat-Pak Dipstick (Chembio Diagnostic System, Inc) and Uni-Gold™ HIV-1/2 (Trinity Biotech) were evaluated between June and September 2006 using 1433 whole blood samples from hospital patients, pregnant women, voluntary counseling and testing attendees and blood donors. All samples that were reactive on all or any of the five rapid assays and 10% of non-reactive samples were tested on a confirmatory Inno-Lia HIV I/II immunoblot assay (Immunogenetics). Results Three hundred and ninety samples were confirmed HIV-1 antibody positive, while 1043 were HIV negative. The sensitivity at initial testing of Determine, SD Bioline and Uni-Gold™ was 100% (95% CI; 99.1–100) while First Response and Stat-Pak had sensitivity of 99.5% (95% CI; 98.2–99.9) and 97.7% (95% CI; 95.7–98.9), respectively, which increased to 100% (95% CI; 99.1–100) on repeat testing. The initial specificity of the Uni-Gold™ assay was 100% (95% CI; 99.6–100) while specificities were 99.6% (95% CI; 99–99.9), 99.4% (95% CI; 98.8–99.7), 99.6% (95% CI; 99–99.9) and 99.8% (95% CI; 99.3–99.9) for Determine, SD Bioline, First Response and Stat-Pak assays, respectively. There was no any sample which was concordantly false positive in Uni-Gold™, Determine and SD Bioline assays. Conclusion An alternative confirmatory HIV testing strategy based on initial testing on either SD Bioline or Determine assays followed by testing of reactive samples on the Determine or SD Bioline gave 100% sensitivity (95% CI; 99.1–100) and 100% specificity (95% CI; 96–99.1) with Uni-Gold™ as tiebreaker for discordant results.</p

Progress in the prevention of mother to child transmission of HIV in three regions of Tanzania: a retrospective analysis.

Mother to child transmission (MTCT) of HIV-1 remains an important problem in sub-Saharan Africa where most new pediatric HIV-1 infections occur. Early infant diagnosis of HIV-1 using dried blood spot (DBS) PCR among exposed infants provides an opportunity to assess current MTCT rates.We conducted a retrospective data analysis on mother-infant pairs from all PMTCT programs in three regions of northern Tanzania to determine MTCT rates from 2008-2010. Records of 3,016 mother-infant pairs were assessed to determine early transmission among HIV-exposed infants in the first 75 days of life.Of 2,266 evaluable infants in our cohort, 143 had a positive DBS PCR result at ≤ 75 days of life, for an overall transmission rate of 6.3%. Transmission decreased substantially over the period of study as more effective regimens became available. Transmission rates were tightly correlated to maternal regimen: 14.9% (9.5, 20.3) of infants became infected when women received no therapy; 8.8% (6.9, 10.7) and 3.6% (2.4, 4.8) became infected when women received single-dose nevirapine (sdNVP) or combination prophylaxis, respectively; the lowest MTCT rates occurred when women were on HAART, with 2.1% transmission (0.3, 3.9). Treatment regimens changed dramatically over the study period, with an increase in combination prophylaxis and a decrease in the use of sdNVP. Uptake of DBS PCR more than tripled over the period of study for the three regions surveyed.Our study demonstrates significant reductions in MTCT of HIV-1 in three regions of Tanzania coincident with increased use of more effective PMTCT interventions. The changes we demonstrate for the period of 2008-2010 occurred prior to major changes in WHO PMTCT guidelines

Maternal Antiretroviral Regimen by Year, Arusha, Kilimanjaro, Tanga Regions.

<p>Maternal Antiretroviral Regimen by Year, Arusha, Kilimanjaro, Tanga Regions.</p

Population Flowchart.

<p>Population Flowchart.</p

Changes in Early Infant Diagnosis Scale-Up and Percent HIV DNA PCR Positive over Study Period, January 2008– September 2010.

<p>Changes in Early Infant Diagnosis Scale-Up and Percent HIV DNA PCR Positive over Study Period, January 2008– September 2010.</p