Inpatient Point-of-Care HIV Early Infant Diagnosis in Mozambique to Improve Case Identification and Linkage to Antiretroviral Therapy.

INTRODUCTION: Novel approaches to case identification and linkage to antiretroviral therapy (ART) are needed to close gaps in early infant diagnosis (EID) of HIV. Point-of-care (POC) EID is a recent innovation that eliminates the long turnaround times of conventional EID that limit patient management in the inpatient setting. The initial deployment of POC EID in Mozambique focused primarily on outpatient clinics; however, 2 high-volume tier-4 pediatric referral hospitals were also included. METHODS: To assess the impact of inpatient POC EID, a retrospective review of testing and care data from Hospital Central de Beira (HCB) and Hospital Central de Maputo (HCM) was performed for the period September 2017 to July 2018, with comparison to the 8-month pre-POC period when dried blood spots were used for conventional EID. RESULTS: Monthly testing volume increased from 8.5 tests pre-POC to 17.6 tests with POC (P<.001). Among 511 children with POC testing, the median age was 5 months, there was ongoing breastfeeding in 326 (63.8%), and 136 (26.6%) of mothers and 146 (28.6%) of infants had not received ART or antiretroviral prophylaxis, respectively. POC tests were positive in 152 (29.7%) infants, and 52 (37.5%) had a previous negative DNA polymerase chain reaction through the conventional outpatient EID program. Linkage to ART for infants with HIV-positive tests improved 64% during the POC period (P=.002). Inpatient mortality for infected infants during the POC period was 28.2%. Excluding these deaths, 61.2% of eligible infants initiated ART as inpatients, but only 29.8% of those discharged without ART were confirmed to have initiated as outpatients. CONCLUSIONS: Inpatient wards are a high-yield site for EID and ART initiation that have historically been overlooked in programming for prevention of mother-to-child transmission. POC platforms represent a transformative opportunity to increase inpatient testing, make definitive diagnoses, and improve timely linkage to ART. Scale-up plans should prioritize pediatric wards.

Performance of a True Point-of-Care Assay for HIV-1/2 Viral Load Measurement at Antenatal and Postpartum Services.

BACKGROUND: Timely viral load (VL) results during pregnancy and the postpartum period are crucial for HIV disease management and for preventing mother-to-child transmission. Point-of-care (POC) VL testing could reduce turnaround times and streamline patient management. We evaluated the diagnostic performance of the novel m-PIMA HIV-1/2 VL assay (Abbott, Chicago, IL) in Mozambique. SETTING: The study was conducted in prenatal and postpartum consultation rooms in 2 primary health care clinics. Sample collection and testing on m-PIMA were performed by trained nurses. METHODS: HIV-infected pregnant and postpartum women on antiretroviral treatment (ART) or ART naive were tested using both on-site m-PIMA POC and referral laboratory-based real-time VL assays. Linear regression analysis and Bland-Altman plots were used to calculate the agreement between both. FINDINGS: Correlation between venous blood plasma POC and plasma laboratory-based VL was strong (r2 = 0.850, P < 0.01), with good agreement between the methods [overall bias 0.202 log copies/mL (95% CI: 0.366 to 0.772 log copies/mL)]. Using the threshold of 1000 copies/mL, which is used to determine ART failure, the sensitivity and specificity of the POC VL assay were 95.0% (95% CI: 91.6% to 97.3%) and 96.5% (95% CI: 94.2% to 98.0%), respectively. The correlation coefficient between the venous and capillary sample types was 0.983 (r2 = 0.966). CONCLUSIONS: On-site, nurse-performed POC VL testing is feasible and accurate in resource-limited primary health care settings. The operational challenge of plasma separation within clinics for POC testing was successfully overcome using minicentrifuges. The use of capillary blood could simplify the execution of the assay in a clinical environment.

Viral load assay performs comparably to early infant diagnosis assay to diagnose infants with HIV in Mozambique: a prospective observational study

Introduction: Viral load testing is essential to manage HIV disease, especially in infants and children. Early infant diagnosis (EID) is performed using nucleic-acid testing in children under 18 months. Resource-limited health systems face severe challenges to scale-up both viral load and EID to unprecedented levels. Streamlining laboratory systems would be beneficial to improve access to quality testing and to increase efficiency of antiretroviral treatment programmes. We evaluated the performance of viral load testing to serve as an EID assay in children younger than 18 months. Methods: This study was an observational, prospective study, including children between one and 18 months of age who were born to HIV-positive mothers in 134 health facilities in Maputo City and Maputo Province, Mozambique. Dried blood spot specimens from heel or toe pricks were collected between January and April 2018, processed using SPEX buffer for both assays, and tested for routine EID and viral load testing using the Roche CAP/CTM HIV-1 Qualitative v2 and Roche CAP/ CTM HIV-1 Quantitative v2 assays respectively. The sensitivity, specificity and positive and negative predictive values were estimated using the EID results as the reference standard. Results: A total of 1021 infants were included in the study, of which 47% were female. Over 95% of mothers and children were on antiretroviral treatment or received antiretroviral prophylaxis respectively. The sensitivity and specificity of using the viral load assay to detect infection were 100% (95% CI: 96.2 to 100%) and 99.9% (95% CI: 99.4 to 100%). The positive and negative predictive values were 99.0% (95% CI: 94.3 to 100%) and 100% (95% CI: 99.6 to 100%). The McNemar's test was 1.000 and Cohen's kappa was 0.994. Conclusions: The comparable performance suggests that viral load assays can be used as an infant diagnostic assay. Infants with either low levels of viraemia or high cycle threshold values should be repeat tested to ensure the result is truly positive prior to treatment initiation, regardless of assay used. Viral load assays could replace traditional EID testing, substantially streamlining molecular laboratory services for children and lowering costs, with the additional advantage of providing baseline viral load results for antiretroviral treatment management.

Proportions of CD4 test results indicating advanced HIV disease remain consistently high at primary health care facilities across four high HIV burden countries.

BACKGROUND: Globally, nearly 22 million HIV-infected patients are currently accessing antiretroviral treatment; however, almost one million people living with HIV died of AIDS-related illnesses in 2018. Advanced HIV disease remains a significant issue to curb HIV-related mortality. METHODS: We analyzed 864,389 CD4 testing records collected by 1,016 Alere Pima Analyzers implemented at a variety of facilities, including peripheral facilities, between January 2012 and December 2016 across four countries in sub-Saharan Africa. Routinely collected data and programmatic records were used to analyze the median CD4 counts and proportions of patients with advanced HIV disease by country, facility type, and year. RESULTS: Median CD4 counts were between 409-444 cells/ul each year since 2012 with a median in 2016 of 444 cells/ul (n = 319,829). The proportion of test results returning CD4 counts above 500 cells/ul has increased slowly each year with 41.8% (95% CI: 41.6-41.9%) of tests having a CD4 count above 500 cells/ul in 2016. Median CD4 counts were similar across facility types. The proportion of test results indicating advanced HIV disease has remained fairly consistent: 19.4% (95% CI: 18.8-20.1%) in 2012 compared to 16.1% (95% CI: 16.0-16.3%) in 2016. The proportion of test results indicating advanced HIV disease annually ranged from 14.5% in Uganda to 29.8% in Cameroon. 6.9% (95% CI: 6.8-7.0%) of test results showed very advanced HIV disease (CD4<100 cells/ul) in 2016. CONCLUSIONS: The proportion of CD4 test results indicating advanced disease was relatively high and consistent across four high HIV burden countries.

Viral load assay performs comparably to early infant diagnosis assay to diagnose infants with HIV in Mozambique: a prospective observational study.

INTRODUCTION: Viral load testing is essential to manage HIV disease, especially in infants and children. Early infant diagnosis is performed using nucleic-acid testing in children under 18 months. Resource-limited health systems face severe challenges to scale-up both viral load and early infant diagnosis to unprecedented levels. Streamlining laboratory systems would be beneficial to improve access to quality testing and to increase efficiency of antiretroviral treatment programmes. We evaluated the performance of viral load testing to serve as an early infant diagnosis assay in children younger than 18 months. METHODS: This study was an observational, prospective study, including children between one and 18 months of age who were born to HIV-positive mothers in 134 health facilities in Maputo City and Maputo Province, Mozambique. Dried blood spot specimens from heel or toe pricks were collected between January and April 2018, processed using SPEX buffer for both assays, and tested for routine EID and VL testing using the Roche CAP/CTM HIV-1 Qualitative v2 and Roche CAP/CTM HIV-1 Quantitative v2 assays respectively. The sensitivity, specificity and positive and negative predictive values were estimated using the EID results as the reference standard. RESULTS: A total of 1021 infants were included in the study, of which 47% were female. Over 95% of mothers and children were on antiretroviral treatment or received antiretroviral prophylaxis respectively. The sensitivity and specificity of using the viral load assay to detect infection were 100% (95% CI: 96.2 to 100%) and 99.9% (95% CI: 99.4 to 100%). The positive and negative predictive values were 99.0% (95% CI: 94.3 to 100%) and 100% (95% CI: 99.6 to 100%). The McNemar's test was 1.000 and Cohen's kappa was 0.994. CONCLUSIONS: The comparable performance suggests that viral load assays can be used as an infant diagnostic assay. Infants with either low levels of viraemia or high cycle threshold values should be repeat tested to ensure the result is truly positive prior to treatment initiation, regardless of assay used. Viral load assays could replace traditional early infant diagnosis testing, substantially streamlining molecular laboratory services for children and lowering costs, with the additional advantage of providing baseline viral load results for antiretroviral treatment management.

Point-of-care CD4 technology invalid result rates in public health care settings across five countries.

BACKGROUND: Since 2010, point-of-care (POC) CD4 testing platforms have been introduced in both urban and rural settings to expand access to testing by bringing diagnostic services closer to patients. We conducted an analysis of routinely collected CD4 testing data to determine the invalid result rates associated with POC CD4 testing. METHODS: We analyzed 981,152 CD4 testing records collected from Alere Pima Analyzers between January 2011 and December 2016 across five countries in sub-Saharan Africa. Routinely collected data and programmatic records were used to determine the rate of invalid test results per month, by facility type, and by operator based on cumulative usage during the study period. In addition, frequency of invalid test types and utilization of control beads were assessed. RESULTS: Across the five countries, 75,530 invalid messages were returned, resulting in an overall invalid result rate of 7.7%. The invalid result rate by country ranged from 6.6% to 11.2%. Invalid result rates were consistent across facility types. Invalid result rates were inversely correlated with operator usage: low volume operators (<50 tests over study period) experienced an invalid result rate of 10.2%, while high volume operators (>500 tests over study period) experienced an invalid result rate of 5.5%. Two invalid result types (exposure position control and reagent control) accounted for nearly 50% of invalid results. Routine data showed that control beads were run on 88.3% of days that the device was used. CONCLUSIONS: Our analysis found that the rate of invalid results was consistent across all types of health facilities, indicating that decentralization of POC CD4 testing to lower level health facilities did not exhibit high invalid result rates or increase cartridge wastage. Additionally, invalid result rates were inversely correlated to operator usage, with high-volume operators experiencing lower invalid result rates than low-volume operators. POC CD4 testing can, therefore, be performed in decentralized national testing programs; however, adequate training, quality assurance, routine monitoring, and ongoing mentorship should also be implemented for success.

Performance of point-of-care birth HIV testing in primary health care clinics: An observational cohort study.

BACKGROUND: Failure to timely diagnose HIV in infants is a major barrier for scaling-up paediatric antiretroviral treatment (ART). WHO recommends birth testing for earlier diagnosis and to improve test coverage, but current diagnosis takes 2-3 weeks to complete, thereby limiting the ability of care givers to provide follow-on care, especially in low-resource settings. We evaluated the benefit of implementing rapid diagnosis of HIV at birth in primary health care maternity wards in Mozambique. METHODS AND FINDINGS: Infants born to HIV-infected mothers delivering consecutively at eight primary health care clinics were tested within 24 hours of delivery using on-site POC (Alere q HIV1/2 Detect) and standard laboratory (Roche COBAS AmpliPrep/TaqMan HIV-1 qualitative assay v2.0) testing. Infants were also tested at 4-6 weeks of age with both assays. Of 2,350 HIV-exposed infants enrolled in this implementation research study, 33 tested HIV-positive at birth on both assays. Sensitivity and specificity of POC testing compared with laboratory testing at birth were 100% (95% CI 89·4-100·0) and 100% (95% CI 99·8-100·0), respectively. At 4-6 weeks of age, 61 infants were identified as HIV-positive; of these 29 (47·5%) had a positive test at birth. Testing at both birth and 4-6 weeks identified 71 HIV-positive infants compared with 61 infants by testing at 4-6 weeks alone, a 16% increase. Two infants tested positive at birth but tested HIV-negative during follow-up. CONCLUSIONS: Adding POC birth testing to the 4-6 week screen may increase access to HIV diagnosis and expedite ART initiation in primary health care settings within low resource settings. Guidance on appropriate confirmatory HIV testing algorithms for birth testing is needed.

Effect of point-of-care early infant diagnosis on antiretroviral therapy initiation and retention of patients.

OBJECTIVE: We measured the effect of point-of-care (POC) early infant HIV testing on antiretroviral therapy initiation rates and retention in care among infants in Mozambique. DESIGN: A cluster-randomized trial was conducted in 16 primary healthcare centres providing either on-site POC arm (n = 8) or referred laboratory [standard-of-care (SOC) arm; n = 8] infant HIV testing. METHODS: The primary outcomes were the proportion of HIV-positive infants initiating antiretroviral therapy within 60 days of sample collection, and the proportion of HIV-positive infants who initiated antiretroviral therapy that were retained in care at 90 days of follow-up. RESULTS: The proportion of HIV-positive infants initiating antiretroviral therapy within 60 days of sample collection was 89.7% (157 of 175) for the POC arm and 12.8% (13 of 102) for the SOC arm [relative risk (RR)(adj) 7.34; P < 0.001]. The proportion of HIV-positive infants who initiated antiretroviral therapy that were retained in care at 90 days of follow-up was 61.6% (101 of 164) for the POC arm and 42.9% (21 of 49) for the SOC arm [RR(adj) 1.40; P < 0.027]. The median time from sample collection to antiretroviral therapy initiation was less than 1 day (interquartile range: 0-1) for the POC arm and 127 days (44-154; P < 0.001) for the SOC arm. CONCLUSION: POC infant HIV testing enabled clinics to more rapidly diagnose and provide treatment to HIV-infected infants. This reduced opportunities for pretreatment loss to follow-up and enabled a larger proportion of infants to receive test results and initiate antiretroviral therapy. The benefits of faster HIV diagnosis and antiretroviral treatment may also improve early retention in care.

Point-Of-Care p24 Infant Testing for HIV May Increase Patient Identification despite Low Sensitivity.

The long delay in returning test results during early infant diagnosis of HIV (EID) often causes loss-to-follow-up prior to antiretroviral treatment (ART) initiation in resource-limited settings. A point-of-care (POC) test may help overcome these challenges. We evaluated the performance of the LYNX p24 Antigen POC test in Mozambique. 879 HIV-exposed infants under 18 months of age were enrolled consecutively at three primary healthcare clinics (PHC). Lancet heel-drawn blood was tested on-site by nurses using a prototype POC test for HIV Gag p24 antigen detection. Results of POC testing were compared to laboratory-based nucleic acid testing on dried blood spots. A comparison of the effect of sensitivity and timely test results return on successful diagnosis by POC and laboratory-based platforms was also calculated. The sensitivity and specificity of the LYNX p24 Ag test were 71.9%; (95% confidence interval [CI]: 58.5-83.0%) and 99.6% (95% CI: 98.9-99.9%), respectively. The predictive value of positive and negative tests were 93.2% (95% CI: 81.3-98.6%) and 97.9% (95% CI: 96.8-98.8%), respectively. Overall agreement was high (Cohen Kappa = 0.80; 95% CI: 0.71-0.89). Despite its lower sensitivity, the POC test had the potential to provide test results to up to 81% more patients compared to the laboratory-based test. This prototype POC p24 assay was feasible for use in PHCs but demonstrated low sensitivity for HIV detection. POC EID technologies that perform below standard recommendations may still be valuable diagnostic tools in settings with inefficient EID networks.

Performance Evaluation of the MyT4 Technology for Determining ART Eligibility.

BACKGROUND: In resource-limited countries, CD4 T-cell (CD4) testing continues to be used for determining antiretroviral therapy (ART) initiation eligibility and opportunistic infection monitoring. To support expanded access to CD4 testing, simple and robust technologies are necessary. We conducted this study to evaluate the performance of a new Point-of-Care (POC) CD4 technology, the MyT4, compared to conventional laboratory CD4 testing. METHODS: EDTA venous blood from 200 HIV-positive patients was tested in the laboratory using the MyT4 and BD FACSCalibur™. RESULTS: The MyT4 had an r2 of 0.82 and a mean bias of 12.3 cells/µl. The MyT4 had total misclassifications of 14.7% and 8.8% when analyzed using ART eligibility thresholds of 350 and 500 cells/µl, respectively. CONCLUSIONS: We conclude that the MyT4 performed well in classifying patients using the current ART initiation eligibility thresholds in Mozambique when compared to the conventional CD4 technology.