Operating Characteristics of a Tuberculosis Screening Tool for People Living with HIV in Out-Patient HIV Care and Treatment Services, Rwanda

Tuberculosis preventive treatment opportunities at antiretroviral therapy initiation and follow-up visits

Setting

Twenty-two clinics providing HIV care and treatment in Botswana where tuberculosis (TB) and HIV comorbidity is as high as 49%.

Objectives

To assess eligibility of TB preventive treatment (TPT) at antiretroviral therapy (ART) initiation and at four follow-up visits (FUVs), and to describe the TB prevalence and associated factors at baseline and yield of TB diagnoses at each FUV.

Design

A prospective study of routinely collected data on people living with HIV (PLHIV) enrolled into care for the Xpert^® MTB/RIF Package Rollout Evaluation Study between 2012 and 2015.

Results

Of 6041 PLHIV initiating ART, eligibility for TPT was 69% (4177/6041) at baseline and 93% (5408/5815); 95% (5234/5514); 96% (4869/5079); and 97% (3925/4055) at FUV1, FUV2, FUV3, and FUV4, respectively. TB prevalence at baseline was 11% and 2%, 3%, 3% and 6% at each subsequent FUV. At baseline, independent risk factors for prevalent TB were CD4 <200 cells/mm³ (aOR = 1.4, P = 0.030); anemia (aOR = 2.39, P < 0.001); cough (aOR = 11.21, P < 0.001); fever (aOR = 2.15, P = 0.001); and weight loss (aOR = 2.60, P = 0.002).

Conclusion

Eligibility for TPT initiation is higher at visits post-ART initiation, while most cases of active TB were identified at ART initiation. Missed opportunities for TB further compromises TB control effort among PLHIV in Botswana.

Brief Report: Yield and Efficiency of Intensified Tuberculosis Case-Finding Algorithms in 2 High-Risk HIV Subgroups in Uganda

BACKGROUND

Tuberculosis (TB) risk varies among different HIV subgroups, potentially impacting intensified case finding (ICF) performance. We evaluated the performance of the current ICF algorithm [symptom screening, followed by Xpert MTB/RIF (Xpert) testing] in 2 HIV subgroups and evaluated whether ICF performance could be improved if TB screening was based on C-reactive protein (CRP) concentrations.

METHODS

We enrolled consecutive adults with CD4 counts ≤350 cells/µL initiating antiretroviral therapy and performed symptom screening, CRP testing using a low-cost point-of-care (POC) assay, and collected sputum for Xpert testing. We compared the yield and efficiency of the current ICF algorithm to POC CRP-based ICF among patients new to HIV care and patients engaged in care.

RESULTS

Of 1794 patients, 126/1315 (10%) new patients and 21/479 (4%) engaged patients had Xpert-positive TB. The current ICF algorithm detected ≥98% of all TB cases in both subgroups but required ≥85% of all patients to undergo Xpert testing. POC CRP-based ICF halved the proportion of patients in both subgroups requiring Xpert testing relative to the current ICF algorithm and had lower yield among patients engaged in care [81% vs. 100%, difference -19% (95% confidence interval: -41 to 3)]. Among patients new to care, POC CRP-based ICF had similar yield as the current ICF algorithm [93% vs. 98%, difference -6% (95% confidence interval: -11 to 0)].

CONCLUSIONS

Among patients new to care, POC CRP-based screening can improve ICF efficiency without compromising ICF yield, whereas symptom-based screening may be necessary to maximize ICF yield among patients engaged in care.

Realizing the "40 by 2022" Commitment from the United Nations High-Level Meeting on the Fight to End Tuberculosis: What Will It Take to Meet Rapid Diagnostic Testing Needs?

Existing rapid diagnostics offer faster and more sensitive diagnosis of tuberculosis (TB) and simultaneous detection of multidrug-resistant TB. A 5-fold increase in investment in these tools is needed to meet the needs of the TB community and the United Nations’ ambitious 40 million by 2022 diagnosis and treatment target.

The potential gains from full adoption of World Health Organization (WHO)-recommended rapid diagnostics (WRDs) for tuberculosis (TB) are significant, but there is no current analysis of the additional investment needed to reach this goal. We sought to estimate the necessary investment in instruments, tests, and money, using Xpert MTB/RIF (Xpert), which detects Mycobacterium tuberculosis (MTB) and tests for resistance to rifampicin (RIF), as an example. An existing calculator for TB diagnostic needs was adapted to estimate the Xpert needs for a group of 24 countries with high TB burdens. This analysis assumed that countries will achieve the case-finding commitments agreed to at the recent United Nations High-Level Meeting on the Fight to End Tuberculosis, and that countries would adopt the WHO-recommended algorithm in which all people with signs and symptoms of TB receive an Xpert test. When compared to the current investments in these countries, this baseline model revealed that countries would require a 4-fold increase in the number of Xpert modules and a 6-fold increase in the number of Xpert test cartridges per year to meet their full testing needs. The incremental cost of the additional instruments for these countries would total approximately US$474 million, plus an incremental cost each year of cartridges of approximately $586 million, or a 5-fold increase over current investments. A sensitivity analysis revealed a variety of possible changes under alternative scenarios, but most of these changes either do not meet the global goals, are unrealistic, or would result in even greater investment needs. These findings suggest that a major investment is needed in WRD capacity to implement the recommended diagnostic algorithm for TB and reach the case-finding commitments by 2022.