Subclinical tuberculosis and adverse infant outcomes in pregnant women with HIV

Subclinical tuberculosis: a meta-analysis of prevalence and scoping review of definitions, prevalence and clinical characteristics

BACKGROUND

This scoping review aimed to characterise definitions used to describe subclinical tuberculosis (TB), estimate the prevalence in different populations and describe the clinical characteristics and treatment outcomes in the scientific literature.

METHODS

A systematic literature search was conducted using PubMed. We included studies published in English between January 1990 and August 2022 that defined "subclinical" or "asymptomatic" pulmonary TB disease, regardless of age, HIV status and comorbidities. We estimated the weighted pooled proportions of subclinical TB using a random-effects model by World Health Organization reported TB incidence, populations and settings. We also pooled the proportion of subclinical TB according to definitions described in published prevalence surveys.

RESULTS

We identified 29 prevalence surveys and 71 other studies. Prevalence survey data (2002-2022) using "absence of cough of any duration" criteria reported higher subclinical TB prevalence than those using the stricter "completely asymptomatic" threshold. Prevalence estimates overlap in studies using other symptoms and cough duration. Subclinical TB in studies was commonly defined as asymptomatic TB disease. Higher prevalence was reported in high TB burden areas, community settings and immunocompetent populations. People with subclinical TB showed less extensive radiographic abnormalities, higher treatment success rates and lower mortality, although studies were few.

CONCLUSION

A substantial proportion of TB is subclinical. However, prevalence estimates were highly heterogeneous between settings. Most published studies incompletely characterised the phenotype of people with subclinical TB. Standardised definitions and diagnostic criteria are needed to characterise this phenotype. Further research is required to enhance case finding, screening, diagnostics and treatment options for subclinical TB.

The clinical presentation and detection of tuberculosis during pregnancy and in the postpartum period in low- and middle-income countries: A systematic review and meta-analysis

For women infected with Mycobacterium tuberculosis, pregnancy is associated with an increased risk of developing or worsening TB disease. TB in pregnancy increases the risk of adverse maternal and neonatal outcomes, however the detection of TB in pregnancy is challenging. We aimed to identify and summarise the findings of studies regarding the clinical presentation and diagnosis of TB during pregnancy and the postpartum period (within 6 months of birth) in low-and middle-income countries (LMICs). A systematic review was conducted searching Ovid MEDLINE, Embase, CINAHL and Global Index Medicus databases. We included any primary research study of women diagnosed with TB during pregnancy or the postpartum period in LMICs that described the clinical presentation or method of diagnosis. Meta-analysis was used to determine pooled prevalence of TB clinical features and health outcomes, as well as detection method yield. Eighty-seven studies of 2,965 women from 27 countries were included. 70.4% of women were from South Africa or India and 44.7% were known to be HIV positive. For 1,833 women where TB type was reported, pulmonary TB was most common (79.6%). Most studies did not report the prevalence of presenting clinical features. Where reported, the most common were sputum production (73%) and cough (68%). Having a recent TB contact was found in 45% of women. Only six studies screened for TB using diagnostic testing for asymptomatic antenatal women and included mainly HIV-positive women ‒ 58% of women with bacteriologically confirmed TB did not report symptoms and only two were in HIV-negative women. Chest X-ray had the highest screening yield; 60% abnormal results of 3036 women tested. Screening pregnant women for TB-related symptoms and risk factors is important but detection yields are limited. Chest radiography and bacteriological detection methods can improve this, but procedures for optimal utilisation remain uncertain in this at-risk population. Trial registration: Prospero registration number: CRD42020202493.

Tuberculosis in pregnancy

Due to COVID-19 pandemic, the latest progress of the End Tuberculosis (TB) Strategy was far from optimal and services for TB needs to be quickly restored. Pregnancy is a unique opportunity to screen and manage TB, and it is an essential step in TB eradication. Early diagnosis and treatment for active disease can reduce maternal and neonatal morbidities and mortality. The more widespread utilization of newer rapid molecular assays with drug-susceptibility testing has significantly shortened the diagnostic process for active TB disease. First-line anti-TB drugs are proven to be safe in pregnancy. Management of latent TB infection (LTBI) during pregnancy is controversial, but puerperium is a period of increased susceptibility to progress to active disease. Extrapulmonary TB (EPTB), multidrug-resistant TB (MDR-TB) and HIV co-infection remain significant issues surrounding TB management during pregnancy and often require input from a multidisciplinary team including TB experts.

Examining family planning and adverse pregnancy outcomes for women with active tuberculosis disease: a systematic review

OBJECTIVES

(1) Summarise and evaluate the current evidence of tuberculosis (TB)-associated pregnancy outcomes, (2) evaluate the state of the science of family planning during TB treatment and (3) provide recommendations to move forward to improve care and outcomes during TB disease.

DESIGN

Systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines.

DATA SOURCES

PubMed, Embase, CINAHL, Cochrane, Web of Science and Scopus were searched from September 2009 to November 2021.

ELIGIBILITY CRITERIA

Studies were included if they assessed pregnant women with active TB, drug-resistant TB (DR-TB) or TB/HIV coinfection and examined pregnancy, maternal, fetal/birth and TB or TB/HIV coinfection outcomes. Studies were also included if they examined family planning services among women initiating TB treatment.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data using PRISMA guidelines and conducted quality assessment using the Joanna-Briggs Institute Critical Appraisal Tools. The level of evidence was reported using the Johns Hopkins Evidence-Based Practice guidelines.

RESULTS

69 studies were included in this review. Case reports, case series, case controls, cohort studies, secondary data analyses and a service delivery improvement project conducted in 26 countries made up the totality of the evidence. Most studies reported pregnancy complications for mothers (anaemia, postpartum haemorrhage, deaths) and fetuses or newborns (low birth weight, premature birth, and spontaneous or induced abortions). Few studies discussed the value of offering family planning to prevent adverse pregnancy outcomes. One study examined the effect of a provider training on contraceptive use with reported increased contraceptive use.

CONCLUSIONS

Integrating family planning services within a TB treatment programme is essential to reduce adverse TB-associated maternal-child outcomes. Despite well-established adverse pregnancy outcomes, little attention has been paid to family planning to prevent poor pregnancy outcomes for women with TB/DR-TB. Recommendations for clinicians, TB programmes and researchers are provided and reflect evidence presented in this review.