Why do children under 5 years old who come into contact with tuberculosis (TB) need to be treated?

From the Guidelines

Children below 5 years old who have been exposed to tuberculosis (TB) need to be treated because their immune systems are not fully developed, making them more vulnerable to developing severe forms of TB disease, including life-threatening TB meningitis and disseminated TB. Treatment typically involves isoniazid preventive therapy (IPT) at a dose of 10 mg/kg daily (maximum 300 mg) for 6-9 months, as recommended by the American Thoracic Society and the Centers for Disease Control and Prevention 1. For children exposed to drug-resistant TB, alternative regimens may include rifampin for 4 months or a combination of isoniazid and rifapentine once weekly for 12 weeks under direct observation. Before starting treatment, active TB disease must be ruled out through clinical evaluation, chest X-ray, and sometimes other tests, as emphasized in the guidelines for controlling tuberculosis in the United States 1. Young children progress from TB infection to disease more rapidly than adults, often within weeks to months rather than years, and may not show typical symptoms, making preventive treatment crucial, as highlighted in the study on targeted tuberculin testing and treatment of latent tuberculosis infection 1. Regular follow-up appointments are essential to monitor for medication side effects and ensure the treatment is effective. This preventive approach significantly reduces the risk of these vulnerable children developing active TB disease. Key considerations in the management of TB exposure in children include:

• Prompt identification and evaluation of exposed children
• Initiation of preventive therapy for those at high risk of progression to active disease
• Close monitoring for signs of active TB and potential side effects of treatment
• Education of families and caregivers on the importance of adherence to treatment and follow-up appointments, as recommended by the guidelines for controlling tuberculosis in the United States 1. By prioritizing the treatment of children below 5 years old who have been exposed to TB, we can significantly reduce the risk of morbidity and mortality associated with this disease, and improve their overall quality of life.

From the FDA Drug Label

Candidates for preventive therapy who have HIV infection should have a minimum of 12 months of therapy. 2. Close contacts of persons with newly diagnosed infectious tuberculosis (≥ 5 mm) In addition, tuberculin-negative (< 5mm) children and adolescents who have been close contacts of infectious persons within the past 3 months are candidates for preventive therapy until a repeat tuberculin skin test is done 12 weeks after contact with the infectious source. All infants and children younger than 4 years of age with a > 10 mm skin test are included in this category. Children who are less than 4 years old are candidates for isoniazid preventive therapy if they have > 10 mm induration from a PPD Mantoux tuberculin skin test

Kids below 5 years old who contact with TB need to be treated because they are at a higher risk of developing active tuberculosis due to their age and potential exposure to infectious individuals. Preventive therapy is recommended for:

• Close contacts of persons with newly diagnosed infectious tuberculosis
• Children under 4 years old with a > 10 mm skin test
• Children under 4 years old who are close contacts of infectious persons, even if they are tuberculin-negative, until a repeat skin test is done 12 weeks after contact 2

From the Research

Why Kids Below 5 Years Old Who Contact with TB Need to be Treated

• Children under 5 years old are at high risk of progressing from tuberculosis infection to tuberculosis disease after exposure to Mycobacterium tuberculosis, with accompanying high risks of morbidity and mortality 3.
• This age group is more susceptible to tuberculosis due to their immature immune system, making them more likely to develop disseminated forms of tuberculosis 3.
• The risk of progression from infection to disease is higher in young children, making it essential to treat them promptly to prevent severe consequences 3.
• Treatment of latent tuberculosis infection (LTBI) in children is crucial to prevent the progression to active tuberculosis disease, and several effective and safe regimens are available for children, including rifamycin-based regimens and daily isoniazid 4.
• The use of interferon-gamma release assays (IGRAs) and tuberculin skin tests (TSTs) can help identify children with LTBI, allowing for early treatment and prevention of active disease 4.