TB and Malnutrition: Unmasking the Deadly Duo in HIV-Positive Children
"A South African study sheds light on the challenges of diagnosing and treating tuberculosis in children with HIV and severe acute malnutrition."
Tuberculosis (TB), human immunodeficiency virus (HIV), and severe acute malnutrition (SAM) form a deadly trio, especially for children in sub-Saharan Africa. While researchers are working hard to understand how these conditions interact, the combined impact has long been recognized. The convergence of TB, HIV, and SAM creates a perfect storm, making diagnosis and treatment incredibly challenging.
A staggering 650,000 cases of pediatric TB occur annually in the 22 highest-burden countries, resulting in an estimated 140,000 deaths each year. Globally, over 2.6 million children are living with HIV, with 90% of these residing in sub-Saharan Africa. In 2014 alone, HIV was responsible for 150,000 childhood deaths. SAM, encompassing conditions like marasmus and kwashiorkor, accounts for up to 10% of all global mortality in children under five, with marasmus responsible for over 500,000 deaths annually. In South Africa, more than 36,000 cases of childhood TB occur yearly, with about a quarter of these cases believed to be HIV-coinfected.
Recognizing the critical challenges posed by the intersection of HIV, SAM, and TB, researchers conducted a study to investigate the diagnostic difficulties and incidence of TB in HIV-infected children with SAM. The study emphasizes the importance of integrating rigorous TB investigations into the programmatic management of HIV and SAM to improve outcomes for these vulnerable children.
Milestones in HIV and TB
HIV/AIDS cases were first reported in the United States in 1981, and subsequent milestones have shaped the response to the epidemic. Tuberculosis is an ancient disease caused by Mycobacterium tuberculosis and continues to affect people worldwide, causing ill-health for 10 million people each year. HIV infection is a major risk factor for TB, which UNAIDS identifies as the leading cause of illness and death among people living with HIV; TB can be cured.
Unveiling the Challenges: Diagnosing TB in Malnourished, HIV-Positive Children
A recent study published in the International Journal of Tuberculosis and Lung Disease explored the incidence and diagnostic challenges of TB in HIV-infected children also suffering from severe acute malnutrition (SAM). This post-hoc analysis was conducted using data from a randomized controlled trial that enrolled antiretroviral therapy-naive, HIV-infected children with SAM in Durban, South Africa.
- Setting: The research was based at an academic tertiary referral hospital in Durban, South Africa.
- Objective: The primary goal was to determine the incidence and challenges in diagnosing TB in children infected with HIV and SAM.
- Design: The study analyzed data from a randomized controlled trial involving HIV-infected children with SAM who had not yet started antiretroviral therapy.
Evolving Pediatric TB Diagnosis
Recent pediatric TB research in sub-Saharan Africa has examined diagnostic methods in children, including those affected by HIV and malnutrition. In a Ugandan cross-sectional study of children with severe acute malnutrition, GeneXpert was performed for all participants, while TB-LAM was used for HIV-positive children with CD4 counts below 200; chest X-rays were used for children with cough and difficulty breathing. Research on urine lateral-flow LAM reported that results above Grade 1 may help identify severely malnourished children eligible for rapid TB treatment, whereas low-intensity Grade 1 results may not be useful for that purpose.
Comparing Risk and Diagnosis
The sources describe a growing concern about infectious-disease morbidity and mortality among children who are HIV-exposed but uninfected, particularly in settings where tuberculosis is common. Diagnosing TB in HIV-infected children is difficult because disease may be pauci-bacillary and obtaining suitable specimens from young children can be challenging. A TB diagnosis therefore relies on exposure history, clinical assessment, and all available evidence, while WHO recommends nucleic acid amplification tests and a four-drug intensive-phase regimen that includes ethambutol.
Moving Forward: Integrating TB Care into HIV and SAM Programs
The study underscores that TB is a common comorbidity in HIV-infected children with SAM. While microbiological confirmation of TB diagnosis is achievable, the high rate of empirical treatment suggests that current diagnostic methods may be insufficient or lead to false negatives. To improve outcomes, rigorous microbiological TB investigations should be integrated into the routine management of HIV and SAM in resource-limited settings. Further research is needed to develop more reliable diagnostic strategies for this vulnerable population, ultimately reducing the burden of this deadly combination of diseases.
Persistent Clinical Challenges
Mycobacterium tuberculosis co-infection remains a significant global problem for children living with HIV. One review reports that TB accounts for one in three deaths related to HIV disease worldwide, although rates have changed over time. HIV can alter the performance of TB screening and diagnostic tests and can complicate prevention and treatment through drug-drug interactions; post-tuberculosis lung disease in children is also described as underappreciated.
Improving Childhood TB Care
The STEP-TB project developed a method for more precisely estimating annual childhood TB cases, doubling the previous estimate to 1 million cases. For the first time, estimates of illness and death among children co-infected with HIV and TB were included. The project helped countries update treatment policies and practices and promoted demand for child-friendly TB treatment.