Decentralization of viral load testing to improve HIV care and treatment cascade in rural Tanzania: observational study from the Kilombero and Ulanga Antiretroviral Cohort

INTRODUCTION

Monitoring HIV viral load (HVL) in people living with HIV (PLHIV) on antiretroviral therapy (ART) is recommended by the World Health Organization. Implementation of HVL testing programs have been affected by logistic and organizational challenges. Here we describe the HVL monitoring cascade in a rural setting in Tanzania and compare turnaround times (TAT) between an on-site and a referral laboratory.

METHODS

In a nested study of the prospective Kilombero and Ulanga Antiretroviral Cohort (KIULARCO) we included PLHIV aged ≥ 15 years, on ART for ≥ 6 months after implementation of routine HVL monitoring in 2017. We assessed proportions of PLHIV with a blood sample taken for HVL, whose results came back, and who were virally suppressed (HVL < 1000 copies/mL) or unsuppressed (HVL ≥ 1000 copies/mL). We described the proportion of PLHIV with unsuppressed HVL and adequate measures taken as per national guidelines and outcomes among those with low-level viremia (LLV; 100-999 copies/mL). We compare TAT between on-site and referral laboratories by Wilcoxon rank sum tests.

RESULTS

From 2017 to 2020, among 4,454 PLHIV, 4,238 (95%) had a blood sample taken and 4,177 (99%) of those had a result. Of those, 3,683 (88%) were virally suppressed. In the 494 (12%) unsuppressed PLHIV, 425 (86%) had a follow-up HVL (102 (24%) within 4 months and 158 (37%) had virologic failure. Of these, 103 (65%) were already on second-line ART and 32/55 (58%) switched from first- to second-line ART after a median of 7.7 months (IQR 4.7-12.7). In the 371 (9%) PLHIV with LLV, 327 (88%) had a follow-up HVL. Of these, 267 (82%) resuppressed to < 100 copies/ml, 41 (13%) had persistent LLV and 19 (6%) had unsuppressed HVL. The median TAT for return of HVL results was 21 days (IQR 13-39) at the on-site versus 59 days (IQR 27-99) at the referral laboratory (p < 0.001) with PLHIV receiving the HVL results after a median of 91 days (IQR 36-94; similar for both laboratories).

CONCLUSION

Robust HVL monitoring is achievable in remote resource-limited settings. More focus is needed on care models for PLHIV with high viral loads to timely address results from routine HVL monitoring.

High failure rates of protease inhibitor-based antiretroviral treatment in rural Tanzania - A prospective cohort study

Background

Poor adherence to antiretroviral drugs and viral resistance are the main drivers of treatment failure in HIV-infected patients. In sub-Saharan Africa, avoidance of treatment failure on second-line protease inhibitor therapy is critical as treatment options are limited.

Methods

In the prospective observational study of the Kilombero & Ulanga Antiretroviral Cohort in rural Tanzania, we assessed virologic failure (viral load ≥1,000 copies/mL) and drug resistance mutations in bio-banked plasma samples 6–12 months after initiation of a protease inhibitor-based treatment regimen. Additionally, viral load was measured before start of protease inhibitor, a second time between 1–5 years after start, and at suspected treatment failure in patients with available bio-banked samples. We performed resistance testing if viral load was ≥1000 copies/ml. Risk factors for virologic failure were analyzed using logistic regression.

Results

In total, 252 patients were included; of those 56% were female and 21% children. Virologic failure occurred 6–12 months after the start of a protease inhibitor in 26/199 (13.1%) of adults and 7/53 of children (13.2%). The prevalence of virologic failure did not change over time. Nucleoside reverse transcriptase inhibitors drug resistance mutation testing performed at 6–12 months showed a positive signal in only 9/16 adults. No cases of resistance mutations for protease inhibitors were seen at this time. In samples taken between 1–5 years protease inhibitor resistance was demonstrated in 2/7 adults. In adult samples before protease inhibitor start, resistance to nucleoside reverse transcriptase inhibitors was detected in 30/41, and to non-nucleoside reverse-transcriptase inhibitors in 35/41 patients. In 15/16 pediatric samples, resistance to both drug classes but not for protease inhibitors was present.

Conclusion

Our study confirms high early failure rates in adults and children treated with protease inhibitors, even in the absence of protease inhibitors resistance mutations, suggesting an urgent need for adherence support in this setting.

Short-course amphotericin B in addition to sertraline and fluconazole for treatment of HIV-associated cryptococcal meningitis in rural Tanzania

BACKGROUND

Cryptococcal meningitis accounts for 15% of all AIDS mortality globally. Most cases in low- and middle-income countries are treated with fluconazole monotherapy, which is associated with a high mortality. New available therapies are needed. Short-course amphotericin B has been shown to be a safe and efficient therapeutic option. Sertraline has in vitro fungicidal activity against Cryptococcus and bi-directional synergy with fluconazole.

METHODS

We conducted an open-label clinical trial to assess the safety and efficacy of sertraline 400 mg/day and fluconazole 1200 mg/day (n = 28) vs sertraline, fluconazole and additional 5 days of amphotericin B deoxycholate 0.7-1 mg/kg (n = 18) for cryptococcal meningitis.

RESULTS

Two-week survival was 64% (18/28) without amphotericin and 89% (16/18) with amphotericin, and 10-week survival was 21% (6/28) vs 61% (11/18), respectively (P = .012). The cerebrospinal fluid (CSF) Cryptococcus clearance rate was 0.264 log₁₀ colony-forming units (CFU)/mL of CSF/day (95% CI: 0.112-0.416) without amphotericin and 0.473 log₁₀ CFU/mL/day (95% CI: 0.344-0.60) with short-course amphotericin (P = .03). Sertraline was discontinued in one participant due to side effects. Four participants receiving amphotericin B experienced hypokalemia <2.4 mEq/L.

CONCLUSIONS

Short-course amphotericin substantially increased CSF clearance and 10-week survival. Adjunctive sertraline improved 2-week CSF fungal clearance but did not improve 10-week mortality compared with published data using fluconazole 1200 mg/day monotherapy (early fungicidal activity 0.15 log₁₀ CFU/mL/day).

Safety and tolerance of lymph node biopsies from chronic HIV-1 volunteers in rural Tanzania

Objective

HIV-1 rapidly establishes a persistent infection that can be contained under life-long antiretroviral therapy (ART) but not cured. One major viral reservoir is the peripheral lymph node (LN) follicles. Studying the impact of novel HIV-1 treatment and vaccination approaches on cells residing in germinal centers is essential for rapid progress towards HIV-1 prevention and cure.

Results

We enrolled 9 asymptomatic adult volunteers with a newly diagnosed HIV-1 infection and CD4 T cell counts ≥ 350/ml. The patients underwent venous blood collection and inguinal lymph node excision surgery in parallel. Mononuclear cells were extracted from blood and tissues simultaneously. Participants were followed up regularly for 2 weeks until complete healing of the surgical wounds. All participants completed the lymph node excision surgery without clinical complications. Among the 9 volunteers, one elite controller was identified. The number of mononuclear cells recovered from lymph nodes ranged from 68 to 206 million and correlated positively with lymph node size. This is the first study to show that lymph node biopsy is a safe procedure and can be undertaken with local experts in rural settings. It provides a foundation for detailed immune response investigations during future clinical trials.