Tuberculosis diagnosis cascade in Blantyre, Malawi: a prospective cohort study

Missed opportunities for TB diagnostic testing among people living with HIV in Zimbabwe: Cross-sectional analysis of the Zimbabwe Population-based HIV Impact Assessment (ZIMPHIA) survey 2015-16

Background

Using data from the Zimbabwe Population-based HIV Impact Assessment survey 2015-2016, we examined the TB care cascade and factors associated with not receiving TB diagnostic testing among adult PLHIV with TB symptoms.

Methods

Statistical Analysis was limited to PLHIV aged 15 years and older in HIV care. Weighted logistic regression with not receiving TB testing as outcome was adjusted for covariates with crude odd ratios (ORs) with p < 0.25. All analyses accounted for multistage survey design.

Results

Among 3507 adult PLHIV in HIV care, 2288 (59.7 %, 95 % CI:58.1-61.3) were female and 2425 (63.6 %, 95 % CI:61.1-66.1) lived in rural areas. 1197(48.7 %, 95 % CI:46.5-51.0) reported being screened for TB symptoms at their last HIV care visit. In the previous 12 months, 639 (26.0 %, 95 % CI:23.9-28.1) reported having symptoms and of those, 239 (37.8 %, 95 % CI:33.3-42.2) received TB testing. Of PLHIV tested for TB, 36 (49.5 %, 95 % CI:35.0-63.1) were diagnosed with TB; 32 (90.3 %, 95 % CI:78.9-100) of those diagnosed with TB received treatment. Never having used IPT was associated with not receiving TB testing.

Conclusion

The results suggest suboptimal utilization of TB screening and diagnostic testing among PLHIV. New approaches are needed to reach opportunities missed in the HIV/TB integrated services.

Impact of active case-finding for tuberculosis on case-notifications in Blantyre, Malawi: A community-based cluster-randomised trial (SCALE)

Active case-finding (ACF) for tuberculosis can help find the "missing millions" with undiagnosed tuberculosis. In a cluster-randomised trial, we investigated impact of ACF on case-notifications in Blantyre, Malawi, where ACF has been intensively implemented following 2014 estimates of ~1,000 per 100,000 adults with undiagnosed TB. Following a pre-intervention prevalence survey (May 2019 to March 2020), constrained randomisation allocated neighbourhoods to either door-to-door ACF (sputum microscopy for reported cough >2 weeks) or standard-of-care (SOC). Implementation was interrupted by COVID-19. Cluster-level bacteriologically-confirmed case-notification rate (CNR) ratio within 91 days of ACF was our redefined primary outcome; comparison between arms used Poisson regression with random effects. Secondary outcomes were 91-day CNR ratios comparing all tuberculosis registrations and all non-ACF registrations. Interrupted time series (ITS) analysis of CNRs in the SOC arm examined prevalence survey impact. (ISRCTN11400592). 72 clusters served by 10 study-supported tuberculosis registration centres were randomised to ACF (261,244 adults, 58,944 person-years follow-up) or SOC (256,713 adults, 52,805 person-years). Of 1,192 ACF participants, 13 (1.09%) were smear-positive. Within 91 days, 113 (42 bacteriologically-confirmed) and 108 (33 bacteriologically-confirmed) tuberculosis patients were identified as ACF or SOC cluster residents, respectively. There was no difference by arm, with adjusted 91-day CNR ratios 1.12 (95% CI: 0.61-2.07) for bacteriologically-confirmed tuberculosis; 0.93 (95% CI: 0.68-1.28) for all tuberculosis registrations; and 0.86 (95%CI: 0.63-1.16) for non-ACF (routinely) diagnosed. Of 7,905 ACF and 7,992 SOC pre-intervention survey participants, 12 (0.15%) and 17 (0.21%), respectively, had culture/Xpert-confirmed tuberculosis. ITS analysis showed no survey impact on SOC CNRs. Despite residual undiagnosed tuberculosis of 150 per 100,000 population, there was no increase in tuberculosis notifications from this previously successful approach targeting symptomatic disease, likely due to previous TB ACF and rapid declines in TB burden. In such settings, future ACF should focus on targeted outreach and demand creation, alongside optimised facility-based screening. Trial Registration: ISRCTN11400592.

Understanding reasons for suboptimal tuberculosis screening in a low-resource setting: A mixed-methods study in the Kingdom of Lesotho

Lesotho has one of the highest tuberculosis (TB) incidence rates in the world, estimated at 654/100,000 population. However, TB detection remains low, with only 51% of people with TB being diagnosed and treated. The aim of this study was to evaluate implementation of TB screening and identify drivers of suboptimal TB screening in Lesotho. We used a convergent mixed methods study design. We collected data on the number of health facility visits and the number of clients screened for TB during March-August, 2019 from one district hospital and one health center. We conducted interviews and focus group discussions with patients and health workers to elucidate the mechanisms associated with suboptimal screening. Out of an estimated 70,393 visitors to the two health facilities, only 22% of hospital visitors and 48% of health center visitors were asked about TB symptoms. Only 2% of those screened at each facility said that they had TB symptoms, comprising a total of 510 people. Lack of training on tuberculosis screening, overall staff shortages, barriers faced by patients in accessing care, and health care worker mistrust of tuberculosis screening procedures were identified as drivers of suboptimal TB screening. TB screening could be improved by ensuring the availability of well-trained, incentivized, and dedicated screeners at health facilities, and by providing TB screening services in community settings.