Point-of-care HIV maternal viral load and early infant diagnosis testing around time of delivery at tertiary obstetric units in South Africa: a prospective study of coverage, results return and turn-around times

INTRODUCTION

Maternal viral load monitoring (mVL) and early infant diagnosis (EID) are necessary to achieve elimination of mother-to-child transmission of HIV. Point-of-care testing can achieve better outcomes compared to centralized laboratory testing (CLT). We describe the first implementation of point-of-care (POC) mVL and EID testing around delivery at four high volume tertiary obstetric units (TOUs) in Gauteng, South Africa.

METHODS

Prospective study of pregnant women living with HIV (WLHIV) and their infants. During the period 1 June 2018 to 31 March 2019, routine staff collected blood specimens from women and their infants around delivery. Specimen collection occurred throughout the week while dedicated POC operators, conducted testing during working hours on weekdays. Descriptive statistics and multivariable Poisson regression with robust error variance were used to describe outcomes and associated factors. Outcomes determined were (i) coverage of mVL and EID testing defined as a proportion of live births to WLHIV admitted at each facility (ii) results returned prior to discharge (iii) turn-around time (TAT) and iv) performance of POC testing compared to CLT.

RESULTS

In total, 8147 live births to pregnant WLHIV were recorded in the implementation period. Of these, 2912 mVL and 5074 EID specimens were included in the analysis, with 131 (4.5%) mVL and 715 (14.1%) EID specimens having initial invalid/error results. Overall coverage of POC mVL and EID testing was 35.6% (range 20.9% to 60.1%) and 61.9% (range 47.0% to 88.0%) respectively. Proportions of POC tested mothers and infants with results returned prior to discharge were 74.3% (range 39.0% to 95.7%) and 73.0% (range 50.0 to 97.9%). Return of results was independently associated with TOU, after-hours specimen collection, having an initial invalid or error result and period of implementation. Overall TAT for specimens collected from mother-infant pairs where both had POC testing, during weekdays was longer for EID compared to mVL testing (median 3.3 hours vs. 2.9 hours, p-value sign test <0.001). POC results were comparable to those from laboratory testing.

CONCLUSION

Accurate and timely POC mVL and EID testing around delivery was implemented with variable success across TOUs. Further scale up would need to address health system factors at facility level and high analytical error rates.

Characterizing the double-sided cascade of care for adolescents living with HIV transitioning to adulthood across Southern Africa

INTRODUCTION

As adolescents and young people living with HIV (AYLH) age, they face a "transition cascade," a series of steps associated with transitions in their care as they become responsible for their own healthcare. In high-income countries, this usually includes transfer from predominantly paediatric/adolescent to adult clinics. In sub-Saharan Africa, paediatric HIV care is mostly provided in decentralized, non-specialist primary care clinics, where "transition" may not necessarily include transfer of care but entails becoming more autonomous for one's HIV care. Using different age thresholds as proxies for when "transition" to autonomy might occur, we evaluated pre- and post-transition outcomes among AYLH.

METHODS

We included AYLH aged <16 years at enrolment, receiving antiretroviral therapy (ART) within International epidemiology Databases to Evaluate AIDS Southern Africa (IeDEA-SA) sites (2004 to 2017) with no history of transferring care. Using the ages of 16, 18, 20 and 22 years as proxies for "transition to autonomy," we compared the outcomes: no gap in care (≥2 clinic visits) and viral suppression (HIV-RNA <400 copies/mL) in the 12 months before and after each age threshold. Using log-binomial regression, we examined factors associated with no gap in care (retention) in the 12 months post-transition.

RESULTS

A total of 5516 AYLH from 16 sites were included at "transition" age 16 (transition-16y), 3864 at 18 (transition-18y), 1463 at 20 (transition-20y) and 440 at 22 years (transition-22y). At transition-18y, in the 12 months pre- and post-transition, 83% versus 74% of AYLH had no gap in care (difference 9.3 (95% confidence interval (CI) 7.8 to 10.9)); while 65% versus 62% were virally suppressed (difference 2.7 (-1.0 to 6.5%)). The strongest predictor of being retained post-transition was having no gap in the preceding year, across all transition age thresholds (transition-16y: adjusted risk ratio (aRR) 1.72; 95% CI (1.60 to 1.86); transition-18y: aRR 1.76 (1.61 to 1.92); transition-20y: aRR 1.75 (1.53 to 2.01); transition-22y: aRR 1.47; (1.21 to 1.78)).

CONCLUSIONS

AYLH with gaps in care need targeted support to prevent non-retention as they take on greater responsibility for their healthcare. Interventions to increase virologic suppression rates are necessary for all AYLH ageing to adulthood.

Concordant upregulation of type II-TGF-beta-receptor, the cyclin-dependent kinases inhibitor P27Kip1 and cyclin E in human atherosclerotic tissue: implications for lesion cellularity

Atherosclerosis is a 'response-to-injury' process associated with chronic inflammation, tissue repair and a considerable cell turnover. These growth-related processes are controlled by the 'cell cycle clock' which is composed of cyclin-dependent kinases (Cdks), their activating subunits, the cyclins, and by inhibitors of Cdks (Ckis). P27 is a Cki which associates with cyclin A-Cdk2, cyclin D-Cdk4 and with cyclin E (CE)-Cdk2 complexes thereby abrogating their catalytic activity leading to potent inhibition of late G1 to S-phase transition. Furthermore, TGF-beta1 mRNA and immunoreactivity are locally increased in atherosclerotic lesions. Since TGF-beta1 growth suppressive function in the late G1 phase may be mediated by p27, blocking the catalytic activity of CE-Cdk2 complexes, via the stimulation of TGF-beta-RI and TGF-beta-RII, we investigated the topographical association between TGF-beta-RI, TGF-beta-RII, P27Kip1 and CE by immunohistochemistry in coronary artery segments without atherosclerosis and carotid atheromatous plaques of 11 patients undergoing carotid endarterectomy. P27-immunoreactivity was present in 11/11 atherosclerotic (92.7 +/- 3.3% of the cells) and 5/5 control (80.9 +/- 3.7% of the cells; P < 0.002 versus control) specimens and localized to nuclei of macrophages (CD68-positive), vascular smooth muscle cells (alpha-actin positive), T-lymphocytes (CD3-positive) as well as to the nuclei of endothelial cells. In the atherosclerotic tissue, TGF-beta-RI and TGF-beta-RII-immunoreactivity was present in 11/11 specimens and localized to inflammatory cells and to cells with VSMC-like-morphology. TGF-beta-RI-immunoreactivity was present in 87.4 +/- 5.3% (controls 75.3 +/- 7.48%; n.s.) and TGF-beta-RII-immunoreactivity was present in 83.7 +/- 6.8% (controls 39.5 +/- 7.3%; P < 0.002) of the cells. Double immunolabeling, and investigation of serial sections revealed co-expression of TGF-beta-RI and TGF-beta-RII in virtually all cells positive for P27. In the atherosclerotic specimens, CE-immunoreactivity was present in all specimens in macrophages (CD68-positive), vascular smooth muscle cells (alpha-actin positive) and in endothelial cells in 12.58 +/- 13.58% of the nuclei whereas in the controls CE staining was restricted to 0.19 +/- 0.43% of the cells (P < 0.001). Importantly, as shown by immunofluorescent double-labeling, we found cells expressing P27 that were simultaneously positive for CE. In summary, the present study provides evidence that TGF-beta1 present in human atherosclerotic tissue may mediate its growth suppressive activity also by p27, blocking the activity of CE-Cdk2 complexes. Quantitative analysis revealed that TGF-beta-RII, p27 and CE are concordantly upregulated in the atherosclerotic tissue with chronic inflammation, supporting the view that TGF-beta1, p27 and CE may play an important role in the processes associated with chronic inflammation and cell turnover in advanced human atherosclerotic plaques. Taken together, these results provide a possible link between the chronic inflammation associated with advanced atherosclerosis, the effects of extracellular growth factors and cell cycle control.