Against all odds: diagnosing tuberculosis in South Africa

An Investigation of Risk Factors Associated with Tuberculosis Transmission in South Africa Using Logistic Regression Model

Background: South Africa has a high burden of tuberculosis (TB) disease and is currently not meeting the national and international reduction outcome targets. The TB prevalence rate of South Africa in 2015 was estimated at approximately 690 per 100,000 population per year, with an incidence rate of about 834 per 100,000 population. This study examines risk factors associated with development of TB in South Africa. Materials and Methods: This study utilised readily available open access secondary data of 2019 South African Health and Demographic Survey from Statistics South Africa (StatsSA) website, which was collected from self-reported information relating to TB in the household questionnaire. The factors analysed were of demographic, socio-economic and health nature. Bivariate and binary logistics analyses were carried out from which appropriate inferences were drawn on the association of TB with demographic, socio-economic and health factors. Results: In multivariate analysis the study revealed that age, personal weight, smoke, alcohol, asthma, province of residence, race and usually coughing were significantly associated with an increased risk of having TB. Conclusions and Recommendations: The results strongly suggest that young and older people coming from black and coloured ethic groups, who are asthmatic and cough frequently, and/or smoking and consuming alcohol are at high risk of developing TB. In addition, those who are overweight appear to have an increased risk of TB transmission, with the Western Cape, Eastern Cape, Northern Cape, Free State, North West and Gauteng being the hardest hit provinces. Hence, the study recommends that these factors must be taken into account in the planning and development of TB policies in order to work successfully towards the achievement of sustainable development goal of reducing TB by 80% before 2030.

TB testing in HIV-positive patients prior to antiretroviral treatment

BACKGROUND: TB diagnosis in patients with HIV is challenging due to the lower sensitivities across tests. Molecular tests are preferred and the Xpert^® MTB/RIF assay has limitations in lower-income settings. We evaluated the performance of loop-mediated isothermal amplification (LAMP) and the lipoarabinomannan (LAM) test in HIV-positive, ART-naïve clinic patients.METHODS: A total of 783 eligible patients were enrolled; three spot sputum samples of 646 patients were tested using TB-LAMP, Xpert, smear microscopy and culture, while 649 patients had TB-LAM testing. Sensitivity, specificity, and negative and positive predictive values were estimated with 95% confidence intervals.RESULTS: Sensitivities for smear microscopy, TB-LAMP and Xpert were respectively 50%, 63% and 74% compared to culture, with specificities of respectively 99.2%, 98.5% and 97.5%. An additional eight were positive on TB-LAM alone. Seventy TB patients (9%) were detected using standard-of-care testing, an additional 27 (3%) were detected using study testing. Treatment was initiated in 57/70 (81%) clinic patients, but only in 56% (57/97) of all those with positive TB tests; 4/8 multidrug-resistant samples were detected using Xpert.CONCLUSION: TB diagnostics continue to miss cases in this high-burden setting. TB-LAMP was more sensitive than smear microscopy, and if followed by culture and drug susceptibility testing as required, can diagnose TB in HIV-positive patients. TB-LAM is a useful add-in test and both tests at the point-of-care would maximise yield.

Therapeutic turnaround times for common laboratory tests in a tertiary hospital in Kenya

METHODS

We evaluated therapeutic TAT for a tertiary hospital in Western Kenya, using a time-motion study focusing specifically on common hematology and biochemistry orders. The aim was to determine significant bottlenecks in diagnostic testing processes at the institution.

RESULTS

A total of 356 (155 hematology and 201 biochemistry) laboratory tests were fully tracked from the time of ordering to availability of results to care providers. The total therapeutic TAT for all tests was 21.5 ± 0.249 hours (95% CI). The therapeutic TAT for hematology was 20.3 ± 0.331 hours (95% CI) while that for biochemistry tests was 22.2 ± 0.346 hours (95% CI). Printing, sorting and dispatch of the printed results emerged as the most significant bottlenecks, accounting for up to 8 hours of delay (Hematology-8.3 ± 1.29 hours (95% CI), Biochemistry-8.5 ± 1.18 hours (95% CI)). Time of test orders affected TAT, with orders made early in the morning and those in the afternoon experiencing the most delays in TAT.

CONCLUSION

Significant inefficiencies exist at multiple steps in the turnaround times for routine laboratory tests at a large referral hospital within an LMIC setting. Multiple opportunities exist to improve TAT and streamline processes around diagnostic testing in this and other similar settings.

Impact of Point-of-Care Xpert MTB/RIF on Tuberculosis Treatment Initiation. A Cluster-randomized Trial

RATIONALE

Point-of-care (POC) diagnostics have the potential to reduce pretreatment loss to follow-up and delays to initiation of appropriate tuberculosis (TB) treatment.

OBJECTIVES

To evaluate the effect of a POC diagnostic strategy on initiation of appropriate TB treatment.

METHODS

We conducted a cluster-randomized trial of adults with cough who were HIV positive and/or at high risk of drug-resistant TB. Two-week time blocks were randomized to two strategies: (1) Xpert MTB/RIF test (Cepheid, Sunnyvale, CA) performed at a district hospital laboratory or (2) POC Xpert MTB/RIF test performed at a primary health care clinic. All participants provided two sputum specimens: one for the Xpert test and the other for culture as a reference standard. The primary outcome was the proportion of participants with culture-positive pulmonary tuberculosis (PTB) initiated on appropriate TB treatment within 30 days.

MEASUREMENTS AND MAIN RESULTS

Between August 22, 2011, and March 1, 2013, 36 two-week blocks were randomized, and 1,297 individuals were enrolled (646 in the laboratory arm, 651 in the POC arm), 159 (12.4%) of whom had culture-positive PTB. The proportions of participants with culture-positive PTB initiated on appropriate TB treatment within 30 days were 76.5% in the laboratory arm and 79.5% in the POC arm (odds ratio, 1.13; 95% confidence interval, 0.51-2.53; P = 0.76; risk difference, 3.1%; 95% confidence interval, -16.2 to 10.1). The median time to initiation of appropriate treatment was 7 days (laboratory) versus 1 day (POC).

CONCLUSIONS

POC positioning of the Xpert test led to more rapid initiation of appropriate TB treatment. Achieving one-stop diagnosis and treatment for all people with TB will require simpler, more sensitive diagnostics and broader strengthening of health systems. Clinical trial registered with www.isrctn.com (ISRCTN 18642314) and www.sanctr.gov.za (DOH-27-0711-3568).

Making HIV testing work at the point of care in South Africa: a qualitative study of diagnostic practices

Background

Point of care testing promises to reduce delays in diagnosing and initiating treatment for infectious diseases such as Human Immuno-deficiency Virus (HIV). In South Africa, decentralized HIV testing with rapid tests offers important lessons for point of care testing programs. Yet, little is known about the strategies of providers and clients to make HIV testing successful in settings short of equipment, human resources and space. We aimed at examining these strategies.

Methods

This paper is based on a larger qualitative study of diagnostic practices across major diseases and actors in homes, clinics, communities, hospitals and laboratories in South Africa. We conducted 101 semi-structured interviews and 7 focus group discussions with doctors, nurses, community health workers, patients, laboratory technicians, policymakers, hospital managers and manufacturers between September 2012 and June 2013 in Durban, Cape Town and Eastern Cape. The topics explored included diagnostic processes and challenges, understanding of diagnosis, and visions of ideal tests. For this paper, the data on HIV testing processes in clinics, communities and hospitals was used.

Results

Strategies to make HIV testing work at point of care involve overcoming constraints in equipment, spaces, human resources and workload and actively managing diagnostic processes. We grouped these strategies into subthemes: maintaining relationships, adapting testing guidelines and practices to stock-outs, to physical space, and to different clients, turning the test into a tool to reach another aim and turning the testing process into a tool to enhance adherence. These adaptive strategies are locally negotiated solutions, often ad-hoc, depending on personal commitment, relationships, human resources, physical space and referral systems. In the process, testing is redefined and repurposed. Not all of these repurposing acts are successful in ensuring a timely diagnosis. Some lead to disruptions, unnecessary testing or delays with at times unclear implications for quality of diagnosis.

Conclusion

Tests shape relationships, professional roles and practices of users at point of care. At the same time, testing processes are dynamic and test results and processes take on new meanings for clients and providers. These insights are crucial for understanding the contexts within which diagnostic devices and policies need to function.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-017-2353-6) contains supplementary material, which is available to authorized users.

Assessing Perceived Challenges to Laboratory Testing at a Malawian Referral Hospital

Adequate laboratory infrastructure in sub-Saharan Africa is vital for tackling the burden of infectious diseases such as human immunodeficiency virus and acquired immune deficiency syndrome, malaria, and tuberculosis, yet laboratories are ill-integrated into the diagnostic and care delivery process in low-resource settings. Although much of the literature focuses on disease-specific challenges around laboratory testing, we sought to identify horizontal challenges to the laboratory testing process through interviews with clinicians involved in the diagnostic process. Based on 22 interviews with physicians, nurses, clinical officers, medical students, and laboratory technicians, technologists and supervisors, we identified 12 distinct challenges in the areas of staff, materials, workflow, and the blood bank. These challenges underscore the informational challenges that compound more visible resource shortages in the laboratory testing process, which lend themselves to horizontal strengthening efforts around the diagnostic process.

A Survey on Use of Rapid Tests and Tuberculosis Diagnostic Practices by Primary Health Care Providers in South Africa: Implications for the Development of New Point-of-Care Tests

BACKGROUND

Effective infectious disease control requires early diagnosis and treatment initiation. Point-of-care testing offers rapid turn-around-times, facilitating same day clinical management decisions. To maximize the benefits of such POC testing programs, we need to understand how rapid tests are used in everyday clinical practice.

METHODS

In this cross-sectional survey study, 400 primary healthcare providers in two cities in South Africa were interviewed on their use of rapid tests in general, and tuberculosis diagnostic practices, between September 2012 and June 2013. Public healthcare facilities were selected using probability-sampling techniques and private healthcare providers were randomly selected from the Health Professional Council of South Africa list. To ascertain differences between the two healthcare sectors 2-sample z-tests were used to compare sample proportions.

RESULTS

The numbers of providers interviewed were equally distributed between the public (n = 200) and private sector (n = 200). The most frequently reported tests in the private sector include blood pressure (99.5%), glucose finger prick (89.5%) and urine dipstick (38.5%); and in the public sector were pregnancy (100%), urine dipstick (100%), blood pressure (100%), glucose finger prick (99%) and HIV rapid test (98%). The majority of TB testing occurs in the public sector, where significantly more providers prefer Xpert MTB/RIF assay, the designated clinical TB diagnostic tool by the national TB program, as compared to the private sector (87% versus 71%, p-value >0.0001). Challenges with regard to TB diagnosis included the long laboratory turn-around-time, difficulty in obtaining sputum samples and lost results. All providers indicated that a new POC test for TB should be rapid and cheap, have good sensitivity and specificity, ease of sample acquisition, detect drug-resistance and work in HIV-infected persons.

CONCLUSION/SIGNIFICANCE

The existing centralized laboratory services, poor quality assurance, and lack of staff capacity deter the use of more rapid tests at POC. Further research into the practices and choices of these providers is necessary to aid the development of new POC tests.

Informatics solutions for bridging the gap between clinical and laboratory services in a low-resource setting

Background

There has been little formal analysis of laboratory systems in resource-limited settings, despite widespread consensus around the importance of a strong laboratory infrastructure.

Objectives

This study details the informational challenges faced by the laboratory at Kamuzu Central Hospital, a tertiary health facility in Malawi; and proposes ways in which informatics can bolster the efficiency and role of low-resource laboratory systems.

Methods

We evaluated previously-collected data on three different aspects of laboratory use. A four-week quality audit of laboratory test orders quantified challenges associated with collecting viable specimens for testing. Data on tests run by the laboratory over a one-year period described the magnitude of the demand for laboratory services. Descriptive information about the laboratory workflow identified informational process breakdowns in the pre-analytical and post-analytical phases and was paired with a 24-hour sample of laboratory data on results reporting.

Results

The laboratory conducted 242 242 tests over a 12-month period. The four-week quality audit identified 54% of samples as untestable. Prohibitive paperwork errors were identified in 16% of samples. Laboratory service workflows indicated a potential process breakdown in sample transport and results reporting resulting from the lack of assignment of these tasks to any specific employee cadre. The study of result reporting time showed a mean of almost six hours, with significant variation.

Conclusions

This analysis identified challenges in each phase of laboratory testing. Informatics could improve the management of this information by streamlining test ordering and the communication of test orders to the laboratory and results back to the ordering physician.