Quantification of antiretroviral drugs in dried blood spot samples by means of liquid chromatography/tandem mass spectrometry

Heavy alcohol use and the HIV care continuum in Kenya: a population-based study

Heavy alcohol use (HAU) can destabilize engagement along the HIV care continuum. Population-based studies assessing associations of HAU with HIV treatment outcomes are lacking, especially in sub-Saharan Africa. We leveraged data from the Kenya Population-based HIV Impact Assessment to identify associations of self-reported HAU, assessed using two items measuring the frequency and quantity of past-year alcohol consumption, with serum biomarkers for HIV serostatus unawareness, antiretroviral therapy (ART) non-use, and HIV viremia (≥1000 RNA copies/mL). Overall and sex-stratified survey-weighted logistic regression with jackknife variance estimation modeled adjusted odds ratios (adjOR) of HIV treatment indicators by HAU. Overall, 1491 persons living with HIV aged 15-64 years (68.4% female) were included. The prevalence of HAU was 8.9% (95% confidence interval [95%CI]: 6.8-11.0%) and was significantly more pronounced in males than females (19.6% vs. 4.0%, p < 0.001). In multivariable analysis, HAU was significantly (p < 0.001) associated with HIV serostatus unawareness (adjOR = 3.65, 95%CI: 2.14-6.23), ART non-use (adjOR = 3.81, 95%CI: 2.25-6.43), and HIV viremia (adjOR = 3.13, 95%CI: 1.85-5.32). Incorporating sex-specific alcohol use screening into HIV testing and treatment services in populations where HAU is prevalent could optimize clinical outcomes along the HIV care continuum.

The state of the pediatric HIV epidemic in Lesotho

OBJECTIVE

Lesotho does not have reliable data on HIV prevalence in children, relying on estimates generated from program data. The 2016 Lesotho Population-based HIV Impact Assessment (LePHIA) aimed to determine HIV prevalence among children 0-14 years to assess the effectiveness of the prevention of mother-to-child transmission (PMTCT) program and guide future policy.

METHODS

A nationally representative sample of children under 15 years underwent household-based, two-stage HIV testing from November 2016-May 2017. Children <18 months with a reactive screening test were tested for HIV infection using total nucleic acid (TNA) PCR. Parents (61.1%) or legal guardians (38.9%) provided information on children's clinical history. Children aged 10-14 years also answered a questionnaire on knowledge and behaviors.

RESULTS

HIV prevalence was 2.1% [95% confidence interval (CI): 1.5-2.6]. Prevalence in 10-14 year olds (3.2%; 95% CI: 2.1, 4.2) was significantly greater compared to 0-4 year olds (1.0%; 95% CI: 0.5, 1.6). HIV prevalence in girls and boys was 2.6% (95% CI: 1.8-3.3) and 1.5% (95% CI: 1.0-2.1), respectively. Based on reported status and/or the presence of detectable antiretrovirals, 81.1% (95% CI: 71.7-90.4) of HIV-positive children were aware of their status, 98.2% (95% CI: 90.7-100.0) of those aware were on antiretroviral therapy (ART) and 73.9% (95% CI: 62.1-85.8) of those on ART were virally suppressed.

CONCLUSIONS

Despite the roll-out of Option B+ in Lesotho in 2013, pediatric HIV prevalence remains high. Further research is required to understand the greater prevalence among girls, barriers to PMTCT, and how to better achieve viral suppression in children with HIV.

Factors associated with viral suppression among adults living with HIV on antiretroviral therapy in Nigeria: Analysis of a population-based survey, 2018

OBJECTIVE

Viral load suppression (VLS) is critical in reducing morbidity and mortality associated with HIV as well as minimizing the likelihood of HIV transmission to uninfected persons. The objective of this study was to identify factors associated with VLS among people living with HIV (PLWH) on antiretroviral (ARV) therapy to inform HIV programme strategies in Nigeria.

METHODS

Adult participants, aged 15-64 years, from the 2018 Nigeria HIV/AIDS Indicator and Impact Survey (NAIIS), who self-reported to be a PLWH or had detectable ARVs, were analysed to examine factors associated with VLS defined as HIV RNA <1000 copies/mL. NAIIS measured HIV prevalence, viral load, ARV and hepatitis B in PLWH. Logistic regression models were used and reported weighted prevalence.

RESULTS

Of 1322 participants, 949 (68.25%) were women and 1287 (96.82%) had detectable ARVs. The median age was 39.31 [interquartile range (IQR): 31.47-47.63] years. Prevalence of VLS was 80.88%. Compared with participants with detectable ARVs, those with undetectable ARVs in their blood specimens had lower odds of VLS [adjusted odds ratio (aOR) = 0.24, 95% confidence interval (CI): 0.08-0.64). Coinfection with hepatitis B and nonnucleoside reverse transcriptase inhibitor metabolites were also associated with lower odds of VLS. Older people (45-54 vs 15-24 years) had increased odds of VLS (aOR = 2.81, 95% CI: 1.14-6.90).

CONCLUSION

Young people and those with undetectable ARVs had lower odds of virological suppression. Targeted interventions focusing on young people and adherence to medication are needed to achieve the UNAIDS 95-95-95 goals for HIV epidemic control.

Point of Care CD4 Testing in National Household Surveys - Results and Quality Indicators from Eleven Population-Based HIV Impact Assessment (PHIA) Surveys

Population-based HIV Impact Assessments (PHIAs) are national household (HH) surveys that provide HIV diagnosis and CD4 testing with an immediate return of results. Accurate CD4 results improve HIV-positive participants' clinical care and inform the effectiveness of HIV programs. Here, we present CD4 results from the PHIA surveys that were conducted in 11 countries in sub-Saharan Africa between 2015 and 2018. All of the HIV-positive participants and 2 to 5% of the HIV-negative participants were offered Pima CD4 (Abbott, IL, USA) point-of-care (POC) tests. The quality of the CD4 test was ensured by conducting instrument verification, comprehensive training, quality control, a review of testing errors and an analysis of unweighted CD4 data by HIV status, age, gender, and antiretroviral (ARV) treatment status. Overall, CD4 testing was completed for 23,085 (99.5%) of the 23,209 HIV-positive and 7,329 (2.7%) of the 270,741 negative participants in 11 surveys. The instrument error rate was 11.3% (range, 4.4% to 15.7%). The median CD4 values among HIV-positive and HIV-negative participants (aged 15+) were 468 cells/mm3 (interquartile range [IQR], 307 to 654) and 811 cells/mm3 (IQR, 647 to 1,013), respectively. Among the HIV-positive participants (aged 15+), those with detectable ARVs had higher CD4 values (508 cells/mm3) than those with undetectable ARVs (385.5 cells/mm3). Among the HIV-positive participants (aged 15+), 11.4% (2,528/22,253) had a CD4 value of less than 200 cells/mm3, and approximately half of them (1,225/2,528 = 48.5%) had detectable ARVs, whereas 51.5% (1,303/2,528) had no detectable ARVs (P < 0.0001). We successfully implemented high quality POC CD4 testing using Pima instruments. Our data come from nationally representative surveys in 11 countries and provide unique insights regarding the CD4 distribution among HIV-positive individuals as well as the baseline CD4 values among HIV-negative individuals. IMPORTANCE The manuscript describes CD4 levels among HIV-positive individuals and baseline CD4 levels among HIV-negative individuals from 11 sub-Saharan countries, thereby highlighting the importance of CD4 markers in the context of the HIV epidemic. Despite increased ARV access in each country, advanced HIV disease (CD4 < 200 cells/mm3) persists among approximately 11% of HIV-positive individuals. Therefore, it is important that our findings are shared with the scientific community to assist with similar implementations of point-of-care testing and to conduct a review of HIV programmatic gaps.

Estimation of HIV-1 Incidence Using a Testing History-Based Method; Analysis From the Population-Based HIV Impact Assessment Survey Data in 12 African Countries

BACKGROUND

Estimating HIV incidence is essential to monitoring progress in sub-Saharan African nations toward global epidemic control. One method for incidence estimation is to test nationally representative samples using laboratory-based incidence assays. An alternative method based on reported HIV testing history and the proportion of undiagnosed infections has recently been described.

METHODS

We applied an HIV incidence estimation method which uses history of testing to nationally representative cross-sectional survey data from 12 sub-Saharan African nations with varying country-specific HIV prevalence. We compared these estimates with those derived from laboratory-based incidence assays. Participants were tested for HIV using the national rapid test algorithm and asked about prior HIV testing, date and result of their most recent test, and date of antiretroviral therapy initiation.

RESULTS

The testing history-based method consistently produced results that are comparable and strongly correlated with estimates produced using a laboratory-based HIV incidence assay (ρ = 0.85). The testing history-based method produced incidence estimates that were more precise compared with the biomarker-based method. The testing history-based method identified sex-, age-, and geographic location-specific differences in incidence that were not detected using the biomarker-based method.

CONCLUSIONS

The testing history-based method estimates are more precise and can produce age-specific and sex-specific incidence estimates that are informative for programmatic decisions. The method also allows for comparisons of the HIV transmission rate and other components of HIV incidence among and within countries. The testing history-based method is a useful tool for estimating and validating HIV incidence from cross-sectional survey data.

HIV Incidence, Recent HIV Infection, and Associated Factors, Kenya, 2007-2018

Nationally representative surveys provide an opportunity to assess trends in recent human immunodeficiency virus (HIV) infection based on assays for recent HIV infection. We assessed HIV incidence in Kenya in 2018 and trends in recent HIV infection among adolescents and adults in Kenya using nationally representative household surveys conducted in 2007, 2012, and 2018. To assess trends, we defined a recent HIV infection testing algorithm (RITA) that classified as recently infected (<12 months) those HIV-positive participants that were recent on the HIV-1 limiting antigen (LAg)-avidity assay without evidence of antiretroviral use. We assessed factors associated with recent and long-term (≥12 months) HIV infection versus no infection using a multinomial logit model while accounting for complex survey design. Of 1,523 HIV-positive participants in 2018, 11 were classified as recent. Annual HIV incidence was 0.14% in 2018 [95% confidence interval (CI) 0.057-0.23], representing 35,900 (95% CI 16,300-55,600) new infections per year in Kenya among persons aged 15-64 years. The percentage of HIV infections that were determined to be recent was similar in 2007 and 2012 but fell significantly from 2012 to 2018 [adjusted odds ratio (aOR) = 0.31, p < .001]. Compared to no HIV infection, being aged 25-34 versus 35-64 years (aOR = 4.2, 95% CI 1.4-13), having more lifetime sex partners (aOR = 5.2, 95% CI 1.6-17 for 2-3 partners and aOR = 8.6, 95% CI 2.8-26 for ≥4 partners vs. 0-1 partners), and never having tested for HIV (aOR = 4.1, 95% CI 1.5-11) were independently associated with recent HIV infection. Although HIV remains a public health priority in Kenya, HIV incidence estimates and trends in recent HIV infection support a significant decrease in new HIV infections from 2012 to 2018, a period of rapid expansion in HIV diagnosis, prevention, and treatment.

Prevalence of HIV drug resistance in Nigeria: results from a cross-sectional, population-based survey of Nigerian adults with unsuppressed viral load

BACKGROUND

HIV drug resistance (HIVDR) surveillance is an important tool to monitor threats to progress towards epidemic control. The characterization of HIVDR in Nigeria at the national level is needed to inform both clinical decisions and population-level HIV policy strategies. This study uses data obtained from the Nigeria HIV/AIDS Indicator and Impact Survey (NAIIS) to describe the prevalence and distribution of HIVDR in Nigeria.

METHODS

NAIIS was a cross-sectional, population-based survey of households throughout Nigeria in 2018. NAIIS was designed to provide estimates of HIV prevalence and related health indicators from a nationally representative sample. The study population included participants aged 15-64 years who tested positive for HIV, had a viral load at least 1000 copies/ml, and had available HIV drug resistance genotypes. HIV isolates were genotyped to detect drug resistance mutations. Individual characteristics of study participants associated with HIVDR were identified using a weighted multivariable logistic regression model.

RESULTS

Of 1355 respondents with available HIV genotypes, 293 (19%) had evidence of drug-resistant mutations (DRMs) that conferred resistance to at least one antiretroviral drug. The majority of DRMs observed conferred resistance to NNRTIs (17.6%) and NRTIs (11.2%). HIVDR was associated with being ART-experienced, longer duration on ART, and lower CD4+ count but not sociodemographic characteristics.

CONCLUSION

The population level DRM prevalence in Nigeria was consistent with what would be expected in a mature HIV treatment landscape. The continued roll out of dolutegravir-anchored regimens should mitigate the impact of NNRTI resistance on population viral load suppression and progress towards epidemic control.

Development of the dried blood spot preparation protocol for comprehensive evaluation of the hematocrit effect

The application of dried blood spots (DBS) has gradually increased in different fields because of its several advantages. The hematocrit (Hct) effect is one major analytical challenge that may affect the quantification accuracy of DBS samples and should be investigated when developing a novel DBS method. However, previous studies usually overlooked the Hct-related distribution bias when evaluating the Hct effect. This study aimed to propose an effective DBS preparation protocol for the comprehensive evaluation of the Hct effect. We selected voriconazole and posaconazole as the demonstration drugs. Fifteen microliters of the blood samples were spotted on DBS cards followed by whole spot extraction. An LC-MS/MS method was first developed to quantify voriconazole and posaconazole in DBS samples. The quantitation accuracy for both azole drugs was within 93.5%-111.7%, except for the accuracies of posaconazole at the LLOQ, which were less than 119%. The intra- and interday precision were below 11%. The validated LC-MS/MS method was used to develop the DBS preparation protocol for evaluating the Hct effect. Three critical parameters that may affect the observed Hct effect were investigated. The results showed that using the solid-state of the target analytes, spiking the target analytes before preparing different Hct levels, and allowing enough equilibrium time after spiking target analytes can provide a more holistic Hct effect evaluation. The validity of the proposed new protocol was verified by conversion factors obtained from 71 paired DBS and plasma samples. Conversion factors calculated by clinical samples were consistent with the Hct effect evaluated by manually prepared DBS samples. This new DBS preparation protocol eliminated the common pitfalls in studying the Hct effect and offered a comprehensive strategy to assess the Hct effect for further DBS studies.

Individual and household factors associated with non-disclosure of positive HIV status in a population-based HIV serosurvey

OBJECTIVES

Non-disclosure of positive HIV status in population-based surveys causes underestimation of national HIV diagnosis and biases inferences about engagement in the care continuum. This study investigated individual and household factors associated with HIV non-disclosure to survey interviewers in Nigeria.

DESIGN

Secondary analysis of a cross sectional population-based household HIV survey.

METHODS

We analyzed data from adults aged 15-64 years who tested positive for HIV and had antiretroviral drugs (ARVs) in their blood from a nationally representative HIV sero-survey conducted in Nigeria in 2018. We considered ARV use as a proxy for knowledge of HIV diagnosis; thus, respondents who self-reported to be unaware of their HIV status were classified as non-disclosers. We estimated the associations between non-disclosure and various sociodemographic, clinical, and household characteristics using weighted logistic regression.

RESULTS

Among 1266 respondents living with HIV who were taking ARVs, 503 (40%) did not disclose their HIV status to interviewers. In multivariable statistical analyses, the adjusted odds of non-disclosure were highest among respondents aged 15-24 years, those with less than a primary school education, and those who were the only person living with HIV in their household.

CONCLUSIONS

Non-disclosure of positive HIV status to survey personnel is common among adults who are receiving treatment in Nigeria. These findings highlight the importance of validating self-reported HIV status in surveys using biomarkers of ARV use. Meanwhile, it is crucial to improve disclosure by strengthening interview procedures and tailoring strategies towards groups that are disproportionately likely to underreport HIV diagnoses.

Toward elimination of mother-to-child transmission of HIV in Malawi: Findings from the Malawi Population-based HIV Impact Assessment (2015–2016)

Background

Malawi spearheaded the development and implementation of Option B+ for prevention of mother-to-child transmission of HIV (PMTCT), providing life-long ART for all HIV-positive pregnant and breastfeeding women. We used data from the 2015–2016 Malawi Population-based HIV Impact Assessment (MPHIA) to estimate progress toward 90-90-90 targets (90% of those with HIV know their HIV-positive status; of these, 90% are receiving ART; and of these, 90% have viral load suppression [VLS]) for HIV-positive women reporting a live birth in the previous 3 years.

Methods

MPHIA was a nationally representative household survey; consenting eligible women aged 15–64 years were interviewed on pregnancies and outcomes, including HIV status during their most recent pregnancy, PMTCT uptake, and early infant diagnosis (EID) testing. Descriptive analyses were weighted to account for the complex survey design. Viral load (VL) results were categorized by VLS (<1,000 copies/mL) and undetectable VL (target not detected/below the limit of detection).

Results

Of the 3,153 women included in our analysis, 371 (10.1%, 95% confidence interval [CI]: 8.8%–11.3%) tested HIV positive in the survey. Most HIV-positive women (84.2%, 95% CI: 79.9%–88.6%) reported knowing their HIV-positive status; of these, 94.9% (95% CI: 91.7%–98.2%) were receiving ART; and of these, 91.2% (95% CI: 87.4%–95.0%) had VLS. Among the 371 HIV-positive women, 76.0% (95% CI: 70.4%–81.7%) had VLS and 66.5% (95% CI: 59.8%–73.2%) had undetectable VL. Among 262 HIV-exposed children, 50.8% (95% CI: 42.8%–58.8%) received EID testing within 2 months of birth, whereas 17.9% (95% CI: 11.9%–23.8%) did not receive EID testing. Of 190 HIV-exposed children with a reported HIV test result, 2.1% (95% CI: 0.0%–4.6%) had positive results.

Conclusions

MPHIA data demonstrate high PMTCT uptake at a population level. However, our results identify some gaps in VLS in postpartum women and EID testing.

Evaluation of accuracy and performance of self-reported HIV and antiretroviral therapy status in the Nigeria AIDS Indicator and Impact Survey (2018)

Background

Data on awareness of HIV status among people living with HIV (PLHIV) are critical to estimating progress toward epidemic control. To ascertain the accuracy of self-reported HIV status and antiretroviral drug (ARV) use in the Nigeria HIV/AIDS Indicator and Impact Survey (NAIIS), we compared self-reported HIV status with HIV rapid diagnostic test (RDT) results and self-reported ARV use with detectable blood ARV levels.

Methods

On the basis of responses and test results, participants were categorized by HIV status and ARV use. Self-reported HIV status and ARV use performance characteristics were determined by estimating sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Proportions and other analyses were weighted to account for complex survey design.

Results

During NAIIS, 186,405 participants consented for interview out of which 58,646 reported knowing their HIV status. Of the 959 (weighted, 1.5%) who self-reported being HIV-positive, 849 (92.1%) tested HIV positive and 64 (7.9%) tested HIV negative via RDT and polymerase chain reaction test for discordant positive results. Of the 849 who tested HIV positive, 743 (89.8%) reported using ARV and 72 (10.2%) reported not using ARV. Of 57,687 who self-reported being HIV negative, 686 (1.2%) tested HIV positive via RDT, with ARV biomarkers detected among 195 (25.1%). ARV was detected among 94.5% of those who self-reported using ARV and among 42.0% of those who self-reported not using ARV. Overall, self-reported HIV status had sensitivity of 52.7% (95% confidence interval [CI]: 49.4%–56.0%) with specificity of 99.9% (95% CI: 99.8%–99.9%). Self-reported ARV use had sensitivity of 95.2% (95% CI: 93.6%–96.7%) and specificity of 54.5% (95% CI: 48.8%–70.7%).

Conclusions

Self-reported HIV status and ARV use screening tests were found to be low-validity measures during NAIIS. Laboratory tests to confirm self-reported information may be necessary to determine accurate HIV and clinical status for HIV studies in Nigeria.

Analytical Techniques for the Analysis of Lopinavir and Ritonavir in Pharmaceutical Dosage Form and Biological Matrices: A Review

Background:

Lopinavir and Ritonavir are the protease inhibitor type of anti-retroviral drugs. Both are used for the treatment of HIV/AIDS. This paper reviews many analytical methods for the analysis of LPV and RTV in pharmaceutical formulations (tablet, capsule, syrup, and bulk) and biological fluids (human plasma, serum, cerebrospinal fluid, rat plasma, and human hair).

Objective:

The study aims to summarize various ana¬lytical techniques, such as Chromatography, Spectrophotometry; and also hyphenated techniques, such as LC-MS/MS, UPLC-MS for analysis of Lopinavir and Ritonavir.

Method:

The review deals with com¬prehensive details about the type of various analytical techniques, such as spectroscopy (UV), chromatography (RP-HPLC, HPTLC, UPLC), and hyphenated techniques, i.e., LC-MS/MS, UPLC-MS for the analysis of lopinavir and ritonavir. These techniques are either explored for the quantification, de¬tection of metabolite or for stability studies of the LPV & RTV.

Conclusion:

The present studies revealed that the HPLC technique along with the spectro-scopic, have been most widely used for the analysis. Out of the developed methods, hyphenated UPLC-MS and LC-MS are very sensitive and helps in the easy estimation of drugs compared to that of the other techniques. This review may provide comprehensive details to the researchers working in the area of analytical research of LPV & RTV.

Opportunities for Closing the Gap in HIV Diagnosis, Treatment, and Viral Load Suppression in Children in Malawi: Results From a 2015-2016 Population-based HIV Impact Assessment Survey

BACKGROUND

Control of the pediatric HIV epidemic is hampered by gaps in diagnosis and linkage to effective treatment. The 2015-2016 Malawi Population-based HIV impact assessment data were analyzed to identify gaps in pediatric HIV diagnosis, treatment, and viral load suppression.

METHODS

In half of the surveyed households, children ages ≥18 months to <15 years were tested using the national HIV rapid test algorithm. Children ≤18 months reactive by the initial rapid test underwent HIV total nucleic acid polymerase chain reaction confirmatory testing. Blood from HIV-positive children was tested for viral load (VL) and presence of antiretroviral drugs. HIV diagnosis and antiretroviral treatment (ART) use were defined using guardian-reporting or antiretroviral detection.

RESULTS

Of the 6166 children tested, 99 were HIV-positive for a prevalence of 1.5% (95% confidence intervals [CI]: 1.1-1.9) and 8.0% (95% CI: 5.6-10.5) among HIV-exposed children. The prevalence of 1.5% was extrapolated to a national estimate of 119,501 (95% CI: 89,028-149,974) children living with HIV (CLHIV), of whom, 30.7% (95% CI: 20.3-41.1) were previously undiagnosed. Of the 69.3% diagnosed CLHIV, 86.1% (95% CI: 76.8-95.6) were on ART and 57.9% (95% CI: 41.4-74.4) of those on ART had suppressed VL (<1000 HIV RNA copies/mL). Among all CLHIV, irrespective of HIV diagnosis or ART use, 57.7% (95% CI: 45.0-70.5) had unsuppressed VL.

CONCLUSIONS

Critical gaps in HIV diagnosis in children persist in Malawi. The large proportion of CLHIV with unsuppressed VL reflects gaps in diagnosis and need for more effective first- and second-line ART regimens and adherence interventions.

Progress Toward the 90-90-90 HIV Targets in Zimbabwe and Identifying Those Left Behind

OBJECTIVE

We present findings from the nationally representative Zimbabwe Population-based HIV Impact Assessment that characterize Zimbabwe's progress toward the Joint United Nations Programme on HIV/AIDS 90-90-90 targets.

DESIGN

We conducted a cross-sectional household survey.

METHODS

Consenting adults and children in the household were eligible to participate in Zimbabwe Population-based HIV Impact Assessment (October 2015-August 2016). Participants completed face-to-face interviews and provided blood for HIV, CD4, viral load, and syphilis testing. Viral load suppression (VLS) was defined as HIV RNA <1000 copies/mL. HIV-positive specimens were tested for the presence of selected antiretroviral drugs. Data were weighted. Analysis was restricted to HIV-positive adults aged 15-64 years.

RESULTS

We enrolled 11,098 men and 14,033 women aged 15-64 years. HIV prevalence was 14.1%. Of those living with HIV, 76.8% (95% confidence interval [CI]: 74.9 to 78.7) were aware of their HIV status or had detectable antiretroviral levels. Of these, 88.4% (95% CI: 87.1 to 89.7) were receiving antiretroviral therapy (ART), and of these people, 85.3% (95% CI: 83.4 to 87.1) had VLS. Male sex age 15-34 years and having 1 or more sexual partners were associated with being unaware of one's HIV-positive status. Age <50 years and not taking cotrimoxazole were associated with being less likely to be being both aware and taking ART. Male sex, age <50 years, and taking cotrimoxazole were associated with being on ART but not having VLS.

CONCLUSIONS

Zimbabwe has made great strides toward epidemic control. Focusing resources on case finding, particularly among men, people aged <35 years, and sexually active individuals can help Zimbabwe attain 90-90-90 targets.

A simplified method for bortezomib determination using dried blood spots in combination with liquid chromatography/tandem mass spectrometry

Bortezomib, a proteinase inhibitor currently used to treat multiple myeloma and mantle cell lymphoma, has a high incidence of adverse reactions and large inter-individual differences in plasma concentrations. A simple, validated LC-MS/MS method for the quantitative analysis of bortezomib in dried blood spot (DBS) samples was developed to provide support for determining the effective concentration range of bortezomib for clinical use. Fifty (i50) μL of spiked blood were added onto Whatman protein saver cards to prepare the DBS samples. Circular cards of 6 mm diameter were punched, extracted by methanol containing the internal standard (apatinib), and injected into the LC-MS/MS system. The method validation included selectivity, linearity, accuracy and precision, stability, matrix effect, recovery and hematocrit. The calibration curve showed correlation coefficient values higher than 0.999 in the range of 0.2 - 20.0 ng/mL for bortezomib. The acceptance criteria of accuracy (relative error < 12.5%) and precision (coefficient of variation < 10.7%) were met in all cases. The matrix effect was<13.2%, and the recovery was between 87.3 and 100.2%. DBS samples were shown to be stable when stored in cold conditions or at room temperature. Different hematocrit values did not significantly affect the accuracy of the measured concentrations. And there are no significant differences between bortezomib concentrations in DBS samples and plasma samples. This new method was successfully used for clinical concentration determinations of bortezomib and can be applied in future therapeutic drug monitoring and pharmacokinetic studies of bortezomib especially in pediatric patients.

Factors associated with unawareness of HIV-positive status in urban Ethiopia: Evidence from the Ethiopia population-based HIV impact assessment 2017-2018

Background

The HIV epidemic in Ethiopia is concentrated in urban areas. Ethiopia conducted a Population-based HIV Impact Assessment (EPHIA) in urban areas between October 2017 and April 2018 to measure the status of the country’s response to the epidemic.

Methods

We conducted field data collection and HIV testing in randomly selected households using the national, rapid testing algorithm with laboratory confirmation of seropositive samples using a supplemental assay. In addition to self-report on HIV diagnosis and treatment, all HIV-positive participants were screened for a set of HIV antiretroviral (ARV) drugs indicative of the first- and second-line regimens. We calculated weighted frequencies and 95% confidence intervals to assess regional variation in participants’ level of unawareness of their HIV-positive status (adjusted for ARV status).

Results

We interviewed 20,170 survey participants 15–64 years of age, of which 19,136 (95%) were tested for HIV, 614 (3.2%) tested positive, and 119 (21%) of HIV-positive persons were unaware of their HIV status. Progress towards the UNAIDS first 90 target (90% of people living with HIV would be aware of their HIV status by 2020) substantially differed by administrative region of the country. In the bivariate analysis using log binomial regression, three regions (Oromia, Addis Ababa, and Harari), male gender, and young age (15–24 years) were significantly associated with awareness of HIV positive status. In multivariate analysis, the same variables were associated with awareness of HIV-positive status.

Conclusion

One-fifth of the HIV-positive urban population were unaware of their HIV-positive status. The number of unaware HIV-positive individuals has a different distribution than the HIV prevalence. National and regional planning and monitoring activities could address this potentially substantial source of undetected HIV infection by increasing HIV testing among young people, men and individuals who do not use condoms.

HIV-1 Recent Infection Testing Algorithm With Antiretroviral Drug Detection to Improve Accuracy of Incidence Estimates

BACKGROUND

HIV-1 incidence calculation currently includes recency classification by HIV-1 incidence assay and unsuppressed viral load (VL ≥ 1000 copies/mL) in a recent infection testing algorithm (RITA). However, persons with recent classification not virally suppressed and taking antiretroviral (ARV) medication may be misclassified.

SETTING

We used data from 13 African household surveys to describe the impact of an ARV-adjusted RITA on HIV-1 incidence estimates.

METHODS

HIV-seropositive samples were tested for recency using the HIV-1 Limiting Antigen (LAg)-Avidity enzyme immunoassay, HIV-1 viral load, ARVs used in each country, and ARV drug resistance. LAg-recent result was defined as normalized optical density values ≤1.5. We compared HIV-1 incidence estimates using 2 RITA: RITA1: LAg-recent + VL ≥ 1000 copies/mL and RITA2: RITA1 + undetectable ARV. We explored RITA2 with self-reported ARV use and with clinical history.

RESULTS

Overall, 357 adult HIV-positive participants were classified as having recent infection with RITA1. RITA2 reclassified 55 (15.4%) persons with detectable ARV as having long-term infection. Those with detectable ARV were significantly more likely to be aware of their HIV-positive status (84% vs. 10%) and had higher levels of drug resistance (74% vs. 26%) than those without detectable ARV. RITA2 incidence was lower than RITA1 incidence (range, 0%-30% decrease), resulting in decreased estimated new infections from 390,000 to 341,000 across the 13 countries. Incidence estimates were similar using detectable or self-reported ARV (R2 > 0.995).

CONCLUSIONS

Including ARV in RITA2 improved the accuracy of HIV-1 incidence estimates by removing participants with likely long-term HIV infection.

Multiresponse Optimization of HPLC Method: Simultaneous Estimation of Protease Inhibitors and NNRTI in Human Plasma

Multiresponse optimization approach to develop a simple isocratic, highly sensitive and accurate HPLC method for the simultaneous determination of Efavirenz, Atazanavir, Lopinavir and Ritonavir in human blood plasma along with carvedilol as an internal standard. Optimized the factors (ACN, buffer concentration and flow rate) effecting and interacting with the responses (k1, Rs2,1, Rs3,2 and tR5) applying Central Composite Design a chemometric tool. All the mathematical models as well as response surfaces were defined and derived for the separation using this strategy. Chromatography was performed on Thermo Hypersil C18 column using mobile phase comprising of ACN: 10 mM KH2PO4 (51.2:48.8) with 1 mL min-1 flow rate and detection wavelength was fixed at 210 nm. The analysis time was within 9 min. The method developed was validated by following "Bioanalytical method validation" [USFDA-CDER, 2001]. The developed method can be applied for bioavailability and pharmacokinetic studies.

The Value of Assessing Self-Reported and Biological Indicators of Outcomes in Evaluating HIV Programs

PURPOSE OF REVIEW

In this manuscript, we present recent findings concerning concordance and discrepancy between biological measures and self-reports of these three outcomes of HIV programs: HIV status, adherence to antiretroviral medications (ARVs) and use of and adherence to pre-exposure prophylaxis medication (PrEP), and condom use/unprotected sex.

RECENT FINDINGS

Recent studies suggest that three successive rapid HIV tests (for those whose first test in positive) might be reasonably inexpensive and valid biological data to collect to combine with self-reports of HIV status, dried blood spots sufficiently affordable to combine with self-reports of adherence to ARVs and use of or adherence to PrEP, and that the discrepancy between self-reports of condom use and biomarkers of unprotected sex may be relatively small in high-income countries. Additional work on assessment of incorrect condom usage and breakage, standardized self-report measures of condom use, and more private data collection methodologies in low-income settings might reduce the recent observed discrepancies even further. Concordance between self-reports of HIV and biomarkers indicating HIV positive status has varied considerably, with much lower rates in low-income countries, where the stigma of HIV is still very high. Recommendation is for combining self-report data with the results of three successive rapid tests for those testing positive. For adherence, again agreement between self-reports and a variety of more objective and/or biological measures is only moderate. Dried blood spots (DBS) may be sufficiently inexpensive in low-resource settings that this may be the best biological method to combine with self-reports. In publications over the last 8 years, the discrepancy between self-reports of condom use and biomarkers for unprotected sex may be even lower than 20% after controlling for other features of the study, particularly in high-income countries. Our results suggest that more careful assessment of incorrect condom use and breakage as reasons other than intentional misreporting should be investigated more carefully and that more private data collection methods such as audio, computer-assisted self-interviewing (ACASI) might be employed more often in low-resource settings to reduce this discrepancy in those settings further. In addition, further analysis of the discrepancy between self-reports of condom use and biomarkers should be conducted of published studies using the correct calculation methods to be more certain of these findings.

Human Immunodeficiency Virus Infection in Adolescents and Mode of Transmission in Southern Africa: A Multinational Analysis of Population-Based Survey Data

Background

Adolescents aged 10–19 years living with human immunodeficiency virus (HIV) (ALHIV), both perinatally infected adolescents (APHIV) and behaviorally infected adolescents (ABHIV), are a growing population with distinct care needs. We characterized the epidemiology of HIV in adolescents included in Population-based HIV Impact Assessments (2015–2017) in Zimbabwe, Malawi, Zambia, Eswatini, and Lesotho.

Methods

Adolescents were tested for HIV using national rapid testing algorithms. Viral load (VL) suppression (VLS) was defined as VL <1000 copies/mL, and undetectable VL (UVL) as VL <50 copies/mL. Recent infection (within 6 months) was measured using a limiting antigen avidity assay, excluding adolescents with VLS or with detectable antiretrovirals (ARVs) in blood. To determine the most likely mode of infection, we used a risk algorithm incorporating recency, maternal HIV and vital status, history of sexual activity, and age at diagnosis.

Results

HIV prevalence ranged from 1.6% in Zambia to 4.8% in Eswatini. Of 707 ALHIV, 60.9% (95% confidence interval, 55.3%–66.6%) had HIV previously diagnosed, and 47.1% (41.9%–52.3%) had VLS. Our algorithm estimated that 72.6% of ALHIV (485 of 707) were APHIV, with HIV diagnosed previously in 69.5% of APHIV and 39.4% of ABHIV, and with 65.3% of APHIV and 33.5% of ABHIV receiving ARV treatment. Only 67.2% of APHIV and 60.5% of ABHIV receiving ARVs had UVL.

Conclusions

These findings suggest that two-thirds of ALHIV were perinatally infected, with many unaware of their status. The low prevalence of VLS and UVL in those receiving treatment raises concerns around treatment effectiveness. Expansion of opportunities for HIV diagnoses and the optimization of treatment are imperative.

Emerging trends in paper spray mass spectrometry: Microsampling, storage, direct analysis, and applications

Recent advancements in the sensitivity of chemical instrumentation have led to increased interest in the use of microsamples for translational and biomedical research. Paper substrates are by far the most widely used media for biofluid collection, and mass spectrometry is the preferred method of analysis of the resultant dried blood spot (DBS) samples. Although there have been a variety of review papers published on DBS, there has been no attempt to unify the century old DBS methodology with modern applications utilizing modified paper and paper-based microfluidics for sampling, storage, processing, and analysis. This critical review will discuss how mass spectrometry has expanded the utility of paper substrates from sample collection and storage, to direct complex mixture analysis to on-surface reaction monitoring.

Hyphenated mass spectrometry techniques for assessing medication adherence: advantages, challenges, clinical applications and future perspectives

Nonadherence to prescribed pharmacotherapy is an understated public health problem globally and is costing many patients their chance to return to good health and healthcare systems billions. Clinicians need an accurate assessment of adherence to medications to aid the clinical decision-making process in the event of poor patient progress and to maximise the patient health outcomes from the drug therapies prescribed. An overview of indirect and direct methods used to measure medication adherence is presented, highlighting the potential for accurate measuring of drugs in biological samples using hyphenated mass spectrometry (MS) techniques to provide healthcare professionals with a reliable evidence base for clinical decision making. In this review we summarise published applications of hyphenated MS techniques for a diverse range of clinical areas demonstrating the rise in the use of such direct methods for assessing medication adherence. Although liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods using plasma, serum and urine samples are the most popular, in recent years increased attention has been given to liquid chromatography high-resolution mass spectrometry (LC-HRMS) methods and alternative biosample matrices including hair, saliva and blood microsamples. The advantages and challenges of using hyphenated MS techniques to address this healthcare problem are also discussed alongside future perspectives.

Dried Blood Spot in Laboratory: Directions and Prospects

Over the past few years, dried blood spot (DBS) technology has become a convenient tool in both qualitative and quantitative biological analysis. DBS technology consists of a membrane carrier (MC) on the surface of which a biomaterial sample becomes absorbed. Modern analytical, immunological or genomic methods can be employed for analysis after drying the sample. DBS has been described as the most appropriate method for biomaterial sampling due to specific associated inherent advantages, including the small volumes of biomaterials required, the absence of a need for special conditions for samples’ storage and transportation, improved stability of analytes and reduced risk of infection resulting from contaminated samples. This review illustrates information on the current state of DBS technology, which can be useful and helpful for biomedical researchers. The prospects of using this technology to assess the metabolomic profile, assessment, diagnosis of communicable diseases are demonstrated.

Use of viral load to improve survey estimates of known HIV-positive status and antiretroviral treatment coverage

OBJECTIVE

To compare alternative methods of adjusting self-reported knowledge of HIV-positive status and antiretroviral (ARV) therapy use based on undetectable viral load (UVL) and ARV detection in blood.

DESIGN

Post hoc analysis of nationally representative household survey to compare alternative biomarker-based adjustments to population HIV indicators.

METHODS

We reclassified HIV-positive participants aged 15-64 years in the 2012 Kenya AIDS Indicator Survey (KAIS) who were unaware of their HIV-positive status by self-report as aware and on antiretroviral treatment if either ARVs were detected or viral load was undetectable (<550 copies/ml) on dried blood spots. We compared self-report to adjustments for ARV measurement, UVL, or both.

RESULTS

Treatment coverage among all HIV-positive respondents increased from 31.8% for self-report to 42.5% [95% confidence interval (CI) 37.4-47.8] based on ARV detection alone, to 42.8% (95% CI 37.9-47.8) when ARV-adjusted, 46.2% (95% CI 41.3-51.1) when UVL-adjusted and 48.8% (95% CI 43.9-53.8) when adjusted for either ARV or UVL. Awareness of positive status increased from 46.9% for self-report to 56.2% (95% CI 50.7-61.6) when ARV-adjusted, 57.5% (95% CI 51.9-63.0) when UVL-adjusted, and 59.8% (95% CI 54.2-65.1) when adjusted for either ARV or UVL.

CONCLUSION

Undetectable viral load, which is routinely measured in surveys, may be a useful adjunct or alternative to ARV detection for adjusting survey estimates of knowledge of HIV status and antiretroviral treatment coverage.

Antiretroviral Concentration in Hair as a Measure for Antiretroviral Medication Adherence: A Systematic Review of Global Literature

This review aims to validate hair antiretroviral concentration (HAC) as a measure for antiretroviral medication adherence. This review included 31 studies that analyzed a total of 11 ARV drugs in four different drug classes. The associations between HAC and non-pharmacokinetic measures were generally lower than the association between HAC and other pharmacokinetic measures: the correlation coefficients (r) ranged from - 0.20 to 0.38 for self-report or pill counts and 0.20 to 0.85 for electronic drug monitoring; HAC and other pharmacokinetic measures were positively correlated with the correlation coefficients (r) ranging from 0.20 to 0.72, 0.34 to 0.86, 0.50 to 0.85 for antiretroviral concentration in plasma, peripheral blood mononuclear cells, and dried blood spots, respectively. HAC was one of the strongest independent predictors of virologic responses. HAC of tenofovir was significantly associated with renal toxicity in large sample studies. This review suggests that HAC is a valid biomarker of antiretroviral medication adherence.

Using dried blood spots to facilitate therapeutic drug monitoring of antiretroviral drugs in resource-poor regions

Objectives

We evaluated whether dried blood spots (DBS) are suitable to monitor combined ART when samples are collected in rural Tanzania and transported over a long distance to a specialized bioanalytical laboratory.

Methods

Plasma and DBS samples were collected in Tanzania from study patients treated with nevirapine, efavirenz or lopinavir. In addition, plasma, whole blood and DBS samples were obtained from a cohort of HIV patients at the site of the bioanalytical laboratory in Switzerland. DBS samples were analysed using a fully automated LC-MS/MS method.

Results

Comparison of DBS versus plasma concentrations of samples obtained from the bridging study in Switzerland indicated an acceptable bias only for nevirapine (18.4%), whereas for efavirenz and lopinavir a pronounced difference of -47.4% and -48.1% was found, respectively. Adjusting the DBS concentrations by the haematocrit and the fraction of drug bound to plasma proteins removed this bias [efavirenz +9.4% (-6.9% to +25.7%), lopinavir +2.2% (-20.0% to +24.2%)]. Storage and transportation of samples from Tanzania to Switzerland did not affect the good agreement between plasma and DBS for nevirapine [-2.9% (-34.7% to +29.0%)] and efavirenz [-9.6% (-42.9% to +23.8%)]. For lopinavir, however, adjusted DBS concentrations remained considerably below [-32.8% (-70.4% to +4.8%)] corresponding plasma concentrations due to decay of lopinavir in DBS obtained under field conditions.

Conclusions

Our field study shows that the DBS technique is a suitable tool for therapeutic drug monitoring in resource-poor regions; however, sample stability remains an issue for certain analytes and therefore needs special consideration.

ART Denial: Results of a Home-Based Study to Validate Self-reported Antiretroviral Use in Rural South Africa

There is increasing interest in home based testing and treatment of HIV to expand access to treatment in sub-Saharan Africa. Such programs rely on self-reported HIV history and use of antiretroviral therapy (ART). However, the accuracy of self-reported ART use in community settings is not well described. In this study, we compared self-reported ART (SR-ART) use in a home based survey against biological exposure to ART (BE-ART), in a population study of older adults in South Africa. Health and Aging in Africa: a Longitudinal Study of an INDEPTH community in South Africa (HAALSI) is a cohort of adults aged 40 +. The baseline home-based interview included self-reported HIV status and ART use. All participants also underwent biological testing for HIV antibodies, viral load and exposure to emtricitabine (FTC) or lamivudine (3TC), which are included in all first-line and second-line ART regimens in the public-sector South African HIV program. We calculated the performance characteristics for SR-ART compared to BE-ART and fit multivariable logistic regression models to identify correlates of invalid SR-ART responses. Of 4560 HAALSI participants with a valid HIV test result available, 1048 (23%) were HIV-positive and 734 [70% of people living with HIV (PLWH)] were biologically validated ART users (BE-ART). The sensitivity of SR-ART use was 64% (95% CI 61-68%) and the specificity was 94% (95% CI 91-96%); the positive predictive value (PPV) was 96% (95% CI 94-98%) and negative predictive value (NPV) was 52% (95% CI 48-56%). We found no sociodemographic predictors of accurate SR-ART use. Over one in three individuals with detectable ART in their blood denied current ART use during a home-based interview. These results demonstrate ongoing stigma related to HIV and its treatment, and have important implications for community health worker programs, clinical programs, and research studies planning community-based ART initiation in the region.

Adherence Measurements in HIV: New Advancements in Pharmacologic Methods and Real-Time Monitoring

PURPOSE OF REVIEW

In this review, we present new developments in antiretroviral adherence, focusing on pharmacological measures and real-time adherence monitoring. In addition, new strategies on how to incorporate these new measures into research and clinical care are proposed.

RECENT FINDINGS

Antiretroviral drug concentrations in hair and dried blood spots are two novel pharmacological measures of cumulative drug adherence and exposure that have been recently evaluated in HIV treatment and pre-exposure prophylaxis. Real-time adherence monitoring using electronic devices has also proven highly informative, feasible, and well accepted, offering the possibility for an immediate intervention when non-adherence is detected. Both approaches offer considerable advantages over traditional adherence measures in predicting efficacy. New methods to objectively monitor adherence in real-time and over long time periods have been developed. Further research is required to better understand how these measures can optimize adherence and, ultimately, improve clinical outcomes in HIV treatment and prevention.

Solvent Front Position Extraction with Semi-Automatic Device as a Powerful Sample Preparation Procedure Prior to Quantitative Instrumental Analysis

The new prototype device is applied to the Solvent Front Position Extraction (SFPE) sample preparation procedure. The mobile phase is deposited onto the chromatographic plate adsorbent layer by the pipette, which is moved, according to programmed movement path, by a 3D printer mechanism. The application of the prototype device to SFPE procedure leads to the increased repeatability of the results and significant reduction of the analysis time in comparison to the classical procedure of chromatogram development. Additionally, the new equipment allows use procedures that are not possible to run using the classic chromatogram development. In this paper, the results of manual and semi-automatic sample preparation with SFPE are compared and the possible application of this prototype device is discussed.

Mechanism-based pharmacokinetic (MBPK) models describe the complex plasma kinetics of three antiretrovirals delivered by a long-acting anti-HIV drug combination nanoparticle formulation

Existing oral antiretroviral (ARV) agents have been shown in human studies to exhibit limited lymph node penetration and lymphatic drug insufficiency. As lymph nodes are a reservoir of HIV, it is critical to deliver and sustain effective levels of ARV combinations in these tissues. To overcome lymph node drug insufficiency of oral combination ARV therapy (cART), we developed and reported a long-acting and lymphocyte-targeting injectable that contains three ARVs-hydrophobic lopinavir (LPV) and ritonavir (RTV), and hydrophilic tenofovir (TFV)-stabilized by lipid excipients in a nanosuspension. A single subcutaneous (SC) injection of this first-generation formulation of drug combination nanoparticles (DcNPs), named TLC-ART101, provided persistent ARV levels in macaque lymph node mononuclear cells (LNMCs) for at least 1 week, and in peripheral blood mononuclear cells (PBMCs) and plasma for at least 2 weeks, demonstrating long-acting pharmacokinetics for all three drugs. In addition, the lymphocyte-targeting properties of this formulation were demonstrated by the consistently higher intracellular drug concentrations in LNMCs and PBMCs versus those in plasma. To provide insights into the complex mechanisms of absorption and disposition of TLC-ART101, we constructed novel mechanism-based pharmacokinetic (MBPK) models. Based upon plasma PK data obtained after single administration of TLC-ART101 (DcNPs) and a solution formulation of free triple-ARVs, the models feature uptake from the SC injection site that respectively routes free and nanoparticle-associated ARVs via the blood vasculature and lymphatics, and their eventual distribution into and clearance from the systemic circulation. The models provided simultaneous description of the complex long-acting plasma and lymphatic PK profiles for all three ARVs in TLC-ART101. The long-acting PK characteristics of the three drugs in TLC-ART101 were likely due to a combination of mechanisms including: (1) DcNPs undergoing preferential lymphatic uptake from the subcutaneous space, (2) retention in nodes during lymphatic first-pass, (3) subsequent slow release of ARVs into blood circulation, and (4) limited extravasation of DcNP-associated ARVs that resulted in longer persistence in the circulation.

Development and validation of an assay to analyze atazanavir in human hair via liquid chromatography/tandem mass spectrometry

RATIONALE

Assays to quantify antiretrovirals in hair samples are increasingly used to monitor adherence and exposure in both HIV prevention and treatment studies. Atazanavir (ATV) is a protease inhibitor used in combination antiretroviral therapy (ART). We developed and validated a liquid chromatography/tandem mass spectrometry (LC/MS/MS)-based method to quantify ATV in human hair, per the NIH Division of AIDS Clinical Pharmacology Quality Assurance (CPQA) program and the FDA bioanalytical method validation guidelines.

METHODS

ATV was extracted from hair using optimized methods and the extracts were injected onto a BDS C-18 column (5 μm, 4.6 × 100 mm), followed by isocratic elution via a mobile phase composed of 55% acetonitrile, 45% water, 0.15% acetic acid, and 4 mM ammonium acetate, at a flow rate of 0.8 mL/min prior to analysis by MS/MS. Levels were quantified using positive electrospray ionization by multiple reaction monitoring (MRM) for the transitions MH⁺ m/z 705.3 to m/z 168.0 and MH⁺ m/z 710.2 to m/z 168.0 for ATV and ATV-d5 (internal standard), respectively.

RESULTS

Our assay demonstrated a linear standard curve (r = 0.99) over the concentration range of 0.0500 ng ATV/mg hair to 20.0 ng/mg hair. The inter- and intraday accuracy of ATV quality control (QC) samples was -1.33 to 4.00% and precision (% coefficient of variation (%CV)) was 1.75 to 6.31%. The %CV for ATV levels in hair samples from highly adherent patients (incurred samples) was less than 10%. No significant endogenous peaks or crosstalk were observed in the specificity test with other HIV drugs. The overall extraction efficiency of ATV from incurred hair samples was greater than 95%.

CONCLUSIONS

This highly sensitive, highly specific and validated assay can be considered for therapeutic drug monitoring for HIV-infected patients on ATV-based ART.

The ART Advantage: Health Care Utilization for Diabetes and Hypertension in Rural South Africa

BACKGROUND

The prevalence of diabetes and hypertension has increased in HIV-positive populations, but there is limited understanding of the role that antiretroviral therapy (ART) programs play in the delivery of services for these conditions. The aim of this study is to assess the relationship between ART use and utilization of health care services for diabetes and hypertension.

METHODS

Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa is a cohort of 5059 adults. The baseline study collects biomarker-based data on HIV, ART, diabetes, and hypertension and self-reported data on health care utilization. We calculated differences in care utilization for diabetes and hypertension by HIV and ART status and used multivariable logistic regressions to estimate the relationship between ART use and utilization of services for these conditions, controlling for age, sex, body mass index, education, and household wealth quintile.

RESULTS

Mean age, body mass index, hypertension, and diabetes prevalence were lower in the HIV-positive population (all P < 0.001). Multivariable logistic regression showed that ART use was significantly associated with greater odds of blood pressure measurement [adjusted odds ratio (aOR) 1.27, 95% confidence interval (CI): 1.04 to 1.55] and blood sugar measurement (aOR 1.26, 95% CI: 1.05 to 1.51), counseling regarding exercise (aOR 1.57, 95% CI: 1.11 to 2.22), awareness of hypertension diagnosis (aOR 1.52, 95% CI: 1.12 to 2.05), and treatment for hypertension (aOR 1.63, 95% CI: 1.21 to 2.19).

CONCLUSIONS

HIV-positive patients who use ART are more likely to have received health care services for diabetes and hypertension. This apparent ART advantage suggests that ART programs may be a vehicle for strengthening health systems for chronic care.

Automated high throughput analysis of antiretroviral drugs in dried blood spots

For therapeutic drug monitoring in remote settings, dried blood spots (DBS) are particularly advantageous, as blood sample collection and handling is uncomplicated. The aim of this study was to develop and validate an automated extraction method for the analysis of nevirapine, efavirenz and lopinavir in DBS samples. Automated extraction was performed with methanol : water (70 : 30 v/v), using a DBS-MS 500 autosampler coupled to a liquid chromatography tandem mass spectrometry system. The autosampler used digital images of each DBS to position the extraction head, sprayed 10 μl of internal standard onto each DBS and extracted a 4-mm disc (Ø) from the centre of each spot by unilateral flow using 25-μl extraction solvent. The analytes were baseline separated on a pentafluorophenyl column and analysed by using electrospray ionization with multiple reaction monitoring in positive polarity mode for nevirapine and lopinavir and in negative mode for efavirenz. The method was linear between 10 and 10 000 ng/ml for all analytes. Automated sample extraction resulted in consistent recoveries (nevirapine: 70 ± 6%, efavirenz: 63 ± 11% and lopinavir: 60 ± 10%) and matrix effects between different donors and concentration levels. Intra-day and inter-day accuracy and precision deviations were ≤15%. Manual and automated extractions of DBS samples collected within the framework of an adherence assessment study in rural Tanzania showed good agreements with deviations of less than 10%. Our study highlights that therapeutic drug monitoring samples obtained in the resource-constrained setting of rural Africa can be reliably determined by automated extraction of DBS. Overall, automatization improved method sensitivity and facilitates analysis of large sample numbers. Copyright © 2017 John Wiley & Sons, Ltd.

Undisclosed HIV infection and antiretroviral therapy use in the Kenya AIDS indicator survey 2012: relevance to national targets for HIV diagnosis and treatment

OBJECTIVES

This analysis assessed the impact of undisclosed HIV infection and antiretroviral therapy (ART) on national estimates of diagnosed HIV and ART coverage in Kenya.

METHODS

HIV-positive dried blood spot samples from Kenya's second AIDS Indicator Survey were tested for an antiretroviral biomarker by liquid chromatography-tandem mass spectrometry. Weighted estimates of diagnosed HIV and ART coverage based on self-report were compared with those corrected for undisclosed HIV infection and ART use based on antiretroviral test results. Multivariate analysis determined factors associated with undisclosed HIV infection and ART use among persons on ART.

RESULTS

The antiretroviral biomarker was detected in 42.5% [confidence interval (CI) 37.4-47.7] of HIV-infected persons. Antiretroviral drugs were present in 90.7% (CI 86.1-95.2) of HIV-infected persons reporting HIV-positive status and receiving ART, 66.7% (CI 59.9-73.4) reporting HIV-positive status irrespective of ART use, 21.0% (CI 13.4-28.6) reporting HIV-negative status, and 19.3% (CI 9.0-29.5) reporting no previous HIV test. After correcting for undisclosed HIV infection and ART use, diagnosed HIV increased from 46.9 to 57.2% and ART coverage increased from 31.8 to 42.8%. Undisclosed HIV infection while on ART was associated with being aged 25-39 years and not visiting a health provider in the past year, while younger age and higher wealth were associated with undisclosed ART use.

CONCLUSION

Substantial levels of undisclosed HIV infection and ART use among persons on ART were observed, resulting in diagnosed HIV underestimated by approximately 112000 persons and ART coverage by approximately 131000 persons. Supplementing self-reported ART status with objective measures of ART use in national population-based serosurveys can improve monitoring of HIV diagnosis and treatment targets in countries.

Providing Safe and Effective Preventative Antiretroviral Prophylaxis to HIV-exposed Newborns via a Novel Drug Delivery System in Tanzania

BACKGROUND

In developing countries, antiretroviral therapy provides life-saving treatment to HIV-positive women and their children before, during and after birth. However, supply chain challenges such as long distances, medication shortages and nonfacility deliveries often compromise consistent access to prophylactic treatment for at-risk infants. A proposed intervention to address these challenges, often referred to as the "Pratt Pouch," allows for liquid-formulation medications, such as nevirapine (NVP), to be repackaged into single-dose pouches. These pouches are distributed antenatally.

METHODS

HIV-positive women at Kilimanjaro Christian Medical Centre in Moshi, Tanzania received 14 pouches each containing a single dose of NVP for prevention of mother-to-child transmission. Women were trained on how to open the pouch and dispense the medication to their infants after delivery. All participating women were asked to return to Kilimanjaro Christian Medical Centre 7-14 days after delivery, where infant blood spots were collected to assess NVP levels.

RESULTS

All enrolled women (21/21) administered NVP to their infants within 24 hours of birth. All enrolled infants (22/22) had NVP blood concentrations over 100 ng/mL and exhibited no health concerns attributable to over or under dosing.

CONCLUSIONS

The Pratt Pouch intervention provides a clinically appropriate solution for addressing liquid-formulation antiretroviral access challenges in developing countries.

Innovations in health and demographic surveillance systems to establish the causal impacts of HIV policies

PURPOSE OF REVIEW

Health and demographic surveillance systems (HDSS), in conjunction with HIV treatment cohorts, have made important contributions to our understanding of the impact of HIV treatment and treatment-related interventions in sub-Saharan Africa. The purpose of this review is to describe and discuss innovations in data collection and data linkage that will create new opportunities to establish the impacts of HIV treatment, as well as policies affecting the treatment cascade, on population health and economic and social outcomes.

RECENT FINDINGS

Novel approaches to routine collection of biomarkers, behavioural data, spatial data, social network information, migration events and mobile phone records can significantly strengthen the potential of HDSS to generate exposure and outcome data for causal analysis of HIV treatment impact and policies affecting the HIV treatment cascade. Additionally, by linking HDSS data to health service administration, education and welfare service records, researchers can substantially broaden opportunities to establish how HIV treatment affects health and economic outcomes when delivered through public sector health systems and at scale.

SUMMARY

As the HIV treatment scaleup in sub-Saharan Africa enters its second decade, it is becoming increasingly important to understand the long-term causal impacts of large-scale HIV treatment and related policies on broader population health outcomes, such as noncommunicable diseases, as well as on economic and social outcomes, such as family welfare and children's educational attainment. By collecting novel data and linking existing data to public sector records, HDSS can create near-unique opportunities to contribute to this research agenda.

Cocaine and metabolite concentrations in DBS and venous blood after controlled intravenous cocaine administration

BACKGROUND

DBS are an increasingly common clinical matrix.

METHODS & RESULTS

Sensitive and specific methods for DBS and venous blood cocaine and metabolite detection by LC-HRMS and 2D GC-MS, respectively, were validated to examine correlation between concentrations following controlled intravenous cocaine administration. Linear ranges from 1 to 200 µg/l were achieved, with acceptable bias and imprecision. Authentic matched specimens' (392 DBS, 97 venous blood) cocaine and benzoylecgonine concentrations were qualitatively similar, but DBS had much greater variability (21.4-105.9 %CV) and were lower than in blood.

CONCLUSION

DBS offer advantages for monitoring cocaine intake; however, differences between capillary and venous blood and DBS concentration variability must be addressed.

The use of mass spectrometry to analyze dried blood spots

Dried blood spots (DBS) typically consist in the deposition of small volumes of capillary blood onto dedicated paper cards. Comparatively to whole blood or plasma samples, their benefits rely in the fact that sample collection is easier and that logistic aspects related to sample storage and shipment can be relatively limited, respectively, without the need of a refrigerator or dry ice. Originally, this approach has been developed in the sixties to support the analysis of phenylalanine for the detection of phenylketonuria in newborns using bacterial inhibition test. In the nineties tandem mass spectrometry was established as the detection technique for phenylalanine and tyrosine. DBS became rapidly recognized for their clinical value: they were widely implemented in pediatric settings with mass spectrometric detection, and were closely associated to the debut of newborn screening (NBS) programs, as a part of public health policies. Since then, sample collection on paper cards has been explored with various analytical techniques in other areas more or less successfully regarding large-scale applications. Moreover, in the last 5 years a regain of interest for DBS was observed and originated from the bioanalytical community to support drug development (e.g., PK studies) or therapeutic drug monitoring mainly. Those recent applications were essentially driven by improved sensitivity of triple quadrupole mass spectrometers. This review presents an overall view of all instrumental and methodological developments for DBS analysis with mass spectrometric detection, with and without separation techniques. A general introduction to DBS will describe their advantages and historical aspects of their emergence. A second section will focus on blood collection, with a strong emphasis on specific parameters that can impact quantitative analysis, including chromatographic effects, hematocrit effects, blood effects, and analyte stability. A third part of the review is dedicated to sample preparation and will consider off-line and on-line extractions; in particular, instrumental designs that have been developed so far for DBS extraction will be detailed. Flow injection analysis and applications will be discussed in section IV. The application of surface analysis mass spectrometry (DESI, paper spray, DART, APTDCI, MALDI, LDTD-APCI, and ICP) to DBS is described in section V, while applications based on separation techniques (e.g., liquid or gas chromatography) are presented in section VI. To conclude this review, the current status of DBS analysis is summarized, and future perspectives are provided.

Analysis of ochratoxin A in dried blood spots - Correlation between venous and finger-prick blood, the influence of hematocrit and spotted volume

We report the improvement of a method for the detection of ochratoxin A (OTA) and its thermal degradation product 2'R-ochratoxin A in dried blood spots (DBS) by high performance liquid chromatographic (HPLC) tandem mass spectrometry (MS/MS). The DBS technique was advanced for the analysis of these two compounds in DBS with unknown amounts of blood as well as varying hematocrit values. Furthermore the comparability of venous vs. capillary blood was investigated. Human whole blood samples were spotted, dried, and extracted with a solvent consisting of acetone, acetonitrile and water for analysis by HPLC-MS/MS. Quantification was carried out by stable isotope labelled internal standards. Blood samples of volunteers (n=50) were used to further optimize and simplify the procedure. Ochratoxin A and 2'R-ochratoxin A concentrations found in the entire spots (approx. 100 μL blood) were compared with punched DBS discs of 8.8mm size containing approximately 20 μL blood. As a result the amounts of both toxins in a punched 8.8mm disc correlate well with the entire DBS. Also the use of capillary blood from finger-pricks versus venous blood was evaluated. The analyte levels correlate as well indicating that the less invasive finger-prick sampling gives also reliable results. The influence of hematocrit was investigated in a range of 25-55% according to the hematocrit in the used real blood samples (34-46% hematocrit). However no significant hematocrit effect was observed for the utilized real blood samples. Moreover different blood volumes were spotted and punched as a minimal spot size is usually recommended for accurate analysis. In this experiment finger-prick samples typically consist of about 90 μL blood. Therefore spots of 75, 100 and 125 μL blood were prepared and analyzed. Similar to the hematocrit effect, no considerable influence was observed.

Frontally eluted components procedure with thin layer chromatography as a mode of sample preparation for high performance liquid chromatography quantitation of acetaminophen in biological matrix

A new concept of using thin-layer chromatography to sample preparation for the quantitative determination of solute/s followed by instrumental techniques is presented Thin-layer chromatography (TLC) is used to completely separate acetaminophen and its internal standard from other components (matrix) and to form a single spot/zone containing them at the solvent front position (after the final stage of the thin-layer chromatogram development). The location of the analytes and internal standard in the solvent front zone allows their easy extraction followed by quantitation by HPLC. The exctraction procedure of the solute/s and internal standard can proceed from whole solute frontal zone or its part without lowering in accuracy of quantitative analysis.

A validated method for quantification of efavirenz in dried blood spots using high-performance liquid chromatography-mass spectrometry

BACKGROUND

Efavirenz (EFV) is one of the preferred components of first-line antiretroviral treatment. EFV is characterized by a long plasma half-life (40-55 hours) with large interpatient variability, which raises the potential for individualization of therapy. Analyses of EFV levels in plasma require specialized facilities (cold storage/transport) which, in resource-limited settings, can be problematic; dried blood spots (DBS)-EFV measurements thus provide a cheap easy alternative for therapeutic drug monitoring. Our aim was to develop and validate a liquid chromatography-mass spectrometry method to quantify EFV in DBS collected as part of clinical trials in resource-limited settings.

METHODS

DBS for standards, quality control samples, and patient samples were excised and then extracted with ethyl acetate/n-hexane (50/50 vol/vol) after addition of internal standard hexobarbital, and 1 mol/L K2CO3. The extract was evaporated to dryness, the residue reconstituted in mobile phase and analyzed directly by liquid chromatography-mass spectrometry. Gradient elution was on a reverse-phase C18 column using 1 mmol/L ammonium acetate in water and acetonitrile. Quantification was by selected reaction monitoring in negative ionization mode. DBS samples were obtained at several time points over 24 hours from HIV+ patients on either 400 or 600 mg EFV in combination with emtricitabine/tenofovir.

RESULTS

The internal standard and EFV eluted at 2.68 and 3.54 minutes, respectively in a 5-minute run time. Matrix effects were minimal (-5.4%). Calibration curves were validated over a concentration range of 25-5000 ng/mL. Intra-assay and interassay variations ranged between 6.7% and 8.7% for imprecision and 100.3% and 104.2% for accuracy. Mean recovery was >64%. The DBS data showed a strong positive correlation with a validated plasma EFV assay (R = 0.9764, P < 0.001). EFV concentrations from DBS were approximately 42% lower than the paired plasma values, and the ratio of blood/plasma did not change over the dosing interval.

CONCLUSIONS

The validated assay is now routinely applied to clinical samples measuring DBS EFV for pharmacokinetic analysis. The methodology is robust, accurate, and sensitive.

Development and Validation of an Enzymatic Method for Total Cholesterol Analysis Using Whole Blood Spot

BACKGROUND

High serum cholesterol represents a risk factor for cardiovascular disease. This study aims to quantify total cholesterol in dried blood spot (DBS) by direct enzymatic method.

METHODS

Three hundred seventeen blood samples with serum cholesterol level ranging from 81 to 337 mg/dl were collected. DBS were manually prepared, cholesterol was extracted using methanol and analyzed by a manual enzymatic method. DBS cholesterol method was validated for imprecision and extraction efficacy. DBS cholesterol values were correlated (training test) with serum values measured by automated enzymatic method (reference method). The obtained correlation was used for predicting serum cholesterol from DBS analysis of a new sample group (validation test, n = 58).

RESULTS

Within-day and between-day coefficient of variation (CV%) were lower than 7.69 and 6.32, respectively. Residual cholesterol in DBS after extraction was 16%. DBS cholesterol and serum cholesterol showed a linear correlation (slope = 0.5217; r = 0.9139) and a bias of -28%. Furthermore, DBS cholesterol values of validation test (n = 58), converted using the training test correlation, were not statistically different compared to the corresponding plasma values (P = 0.9487), and the comparison by Passing and Bablok showed a linear regression with a slope of 1.068 (r = 0.611) and a bias of -0.22%.

CONCLUSIONS

The results show that this enzymatic method is suitable to analyze cholesterol in DBS and it could be automated and used for population screening of total blood cholesterol.

LC-HRMS determination of piperine on rat dried blood spots: A pharmacokinetic study

A liquid chromatography-high resolution mass spectrometry (LC-HRMS) method was developed and validated for the determination of piperine (PPR) on dried blood spots (DBS). DBS samples were prepared by spiking the whole blood with analyte to produce 30 µL of blood spots on specimen collection cards. Chromatographic separation was achieved on an Atlantis dC₁₈ column using acetonitrile and water (0.1% formic acid) (85:15, v/v) as mobile phase in an isocratic mode of elution at a flow rate of 0.75 mL/min. MS detection was carried out in electrospray positive ion mode for the target ions and monitored at m/z 286.1465 for PPR and 272.1303 for the internal standard (IS). The developed method exhibited a linear dynamic range over 0.01-2000 ng/mL for PPR on DBS. The overall extraction recovery of PPR from DBS was 92.5%. Influence of hematocrit and spot volume on DBS was also evaluated and found to be well within the acceptable limits. The method was successfully applied to pharmacokinetic studies of PPR in rats.

Validation and clinical application of a method to quantify nevirapine in dried blood spots and dried breast-milk spots

OBJECTIVES

The validation and clinical application of an LC-MS/MS method for the quantification of nevirapine in dried blood spots (DBS) and dried breast-milk spots (DBMS) are presented.

METHODS

DBS and DBMS were prepared from 50 and 30 μL of nevirapine-spiked whole blood and human breast milk, respectively. Chromatographic separation was achieved on a reverse-phase C18 column with 0.1% formic acid in water/acetonitrile using a solvent gradient programme at a flow rate of 400 μL/min, and detection was by a TSQ Quantum Access triple quadrupole mass spectrometer. The clinical application was evaluated in HIV-positive nursing mothers and their breastfed infants.

RESULTS

The assay was validated over the concentration range 50-10,000 ng/mL. Accuracy ranged from 93.3% to 113.4% and precision ranged from 1.9% to 12.0%. The mean (percentage coefficient of variation) recovery of nevirapine from DBS and DBMS was ≥ 70.7% (≤ 8.2) and the matrix effect was ≤ 1.04 (≤ 6.1). Nevirapine was stable in DBS and DBMS for ≥ 15 months at room temperature and -80°C. Mean (SD) AUC0-12, Cmax and Cmin in maternal plasma versus breast milk were 57,808 ng · h/mL (24,315) versus 55,817 ng · h/mL (22,368), 6140 ng/mL (2605) versus 5231 ng/mL (2215) and 4334 ng/mL (1880) versus 4342 ng/mL (2245), respectively. The milk-to-plasma concentration ratio over the dosing interval was 0.94 (0.15). Infant plasma concentrations 2 and 8 h after maternal dosing were 580.6 ng/mL (464.7-1607) and 584.1 ng/mL (381.5-1570), respectively.

CONCLUSIONS

These methods further extend opportunities for conducting clinical pharmacokinetic studies in nursing mother-infant pairs, especially in resource-limited settings.