Improving diagnosis through integrated testing
“Integration and optimization are at the cutting edge of where diagnostic innovation is going to be in the next few years. The question is, how do we get there?”— Trevor Peter, Senior Scientific Director of Diagnostics Services for the Clinton Health Access Initiative, Inc. (CHAI)
Access to diagnostic services is critical for providing patients with lifesaving treatment and care. Despite significant investments in national laboratory systems across sub-Saharan Africa, there is considerable unmet need for testing services that accurately diagnose patients and monitor their response to therapy in a timely manner.
In December 2018, over 1,200 policymakers, program managers, researchers, and scientists attended the African Society for Laboratory Medicine (ASLM) conference in Abuja, Nigeria, to discuss new and better ways to deliver testing and diagnosis to patients across Africa. At the conference, and with support from Unitaid, CHAI convened a satellite discussion with partners, including ASLM, UNICEF, and the Elizabeth Glaser Pediatric AIDS Foundation (EGPAF), to share evidence in support of the scale up of integrated disease testing to increase patient access to diagnostic services.
The need for diagnostic services
According to UNAIDS, in 2017, only 53 percent of HIV-exposed infants received an early infant diagnosis (EID) test to diagnose the disease and link them to treatment by the recommended eight weeks. In addition, only 40 percent of people living with HIV received viral load (VL) testing, which is an important measurement of the level of HIV present in blood that helps determine whether treatment is working effectively and reduces the risk of disease transmission. Similar diagnostic gaps exist in tuberculosis (TB) care, with only 66 percent of TB cases diagnosed in 2017. Even with improved knowledge of the public health threat posed by drug-resistant TB, only 25 percent of the global multi-drug resistant TB cases were found in 2017.
Although several diagnostic platforms are capable of running tests for a variety of infectious diseases, such as TB and HIV, many laboratories have separate infrastructure systems for each disease and do not integrate testing onto one device. As a result, existing devices are underutilized, leading to wastage and inefficiency, increased costs, and missed opportunities to improve access to testing services for patients.
“There are over 10,000 [diagnostic] devices in the field and, as we expand viral load and early infant diagnosis test[ing] in many countries, we also want to make sure that [existing] devices are being utilized,” said Lara Vojnov, Diagnostics Advisor at the World Health Organization, at the ASLM conference.
To determine whether conducting multiple types of tests using a single laboratory device is operationally feasible in lower-resource settings, CHAI supported the Ministry of Health and Child Care (MOHCC) in Zimbabwe and the Ministry of Health and Population (MOHP) in Malawi to conduct pilot studies of integrated HIV/TB testing on Cepheid’s GeneXpert platform, which has traditionally been used for TB testing alone. The studies aimed to show that integrated testing is a feasible and economical way to provide quality diagnostic services when leveraging existing diagnostic infrastructure.
The Cepheid GeneXpert platform offers a unique opportunity for point-of-care (POC) testing because it is able to decentralize testing services to lower levels of facilities, such as district hospitals and large health centers. There is already a large fleet of devices installed across low- and middle-income countries and, of the approximately 9,400 GeneXpert devices procured across high-burden disease countries in 2017, only around 25 percent of their capacity was utilized. If integrated testing on this platform is feasible, the excess capacity could be used to rapidly – and economically – increase access to POC testing for patients in underserved areas, allowing them to receive the benefits of on-site testing without requiring substantial investment in new diagnostic infrastructure.
Finding solutions in Malawi
Alongside partners, CHAI presented preliminary results of the Malawi study at the ASLM conference, which showed that despite the addition of two new test types (EID and VL), the quality of TB testing services was not compromised. Not only did the addition of the two new test types not slow down the availability of test results, patients actually received results faster. An additional analysis of the potential cost savings associated with introducing integrated testing at a national level showed a 13 percent lower cost-per-test compared to the traditional testing model, which was primarily due to the ability to share device costs and improved staff mentorship and capacity.
To build evidence on whether or not integrated POC testing is actually beneficial and feasible, CHAI supported the MOHP in Malawi to add EID and VL monitoring tests for HIV on the existing GeneXpert platforms that were being used for TB diagnosis. The pilot measured result turnaround time, testing volumes, error rates, treatment initiation rates for HIV-positive infants, and clinical action for people with high VL to assess the impact of POC testing, as well as cost savings before and after the introduction of integrated testing at 10 district hospitals.
“While it has only been six months so far, the pilot has helped to show us which solutions can help us make progress,” said James Kandulu, Deputy Director, Health Support Technical Services at the Malawi MOH. “We are not stopping here and, as long as we have disease, we will continue to work to eliminate it.”
Prioritizing patients in Zimbabwe
Similarly, in Zimbabwe, CHAI worked with the MOHCC to launch an HIV/TB integration pilot at four facilities. The preliminary results show that the device was used more frequently, but not overrun by increased volumes, and that TB testing services were similarly not negatively impacted by the addition EID and VL tests for HIV. The average wait time for results decreased significantly from an average of 14 days to one, which allows HIV-positive infants to access treatment faster, as demonstrated by the 83 percent to 100 percent increase in the number of HIV-positive infants initiated on treatment across the pilot facilities.
“The reason that this data is important is because it translates to impact on patients,” said Raiva Simbi, Deputy Director at the MOHCC in Zimbabwe. “If we can integrate testing at a large scale, patients can get integrated care at the same facility and go back home and get care there, too.”
Broadening integrated testing
The pilots in Malawi and Zimbabwe show that, with appropriate planning, integrated TB/HIV testing on the GeneXpert is operationally feasible, does not compromise current TB services, and improves timeliness and rates of clinical action for HIV patients compared to centralized laboratory testing.
The results of these pilots will be used to inform national scale-up plans in Malawi and Zimbabwe, and also in other CHAI-supported countries introducing integrated testing, including Ethiopia, Tanzania, Kenya, Cameroon, and the Democratic Republic of Congo. CHAI is also working to identify opportunities to integrate testing for other disease areas, such as HPV and HCV, and on other POC devices.
“We want to continue to inspire a patient-centered approach, which is not about the disease, but is about bringing services to the patients,” said Smiljka de Lussigny, Program Manager at Unitaid, during her opening remarks at the ASLM satellite session. “Integration is one way that we can start doing that and truly make a difference in the lives of each and every patient.”
To learn more about CHAI’s work in diagnostics and its session at the ALSM conference, visit http://aslm2018.org/implementing-multi-disease-testing-at-the-near-point-of-care/