What is primary Complex? Discuss the clinical manifestation and diagnostic approach for tuberculosis in children

Primary complex, also known as primary tuberculosis infection, refers to the initial infection with Mycobacterium tuberculosis (M. tuberculosis) in the body.

Get the full solved assignment PDF of MME-303/As-9 of 2024 session now.

In children, primary complex typically occurs following exposure to an individual with active pulmonary tuberculosis. Here’s a discussion on the clinical manifestation and diagnostic approach for tuberculosis in children:

Clinical Manifestations of Tuberculosis in Children:

1. Primary Tuberculosis:

• Asymptomatic Infection: Many children with primary tuberculosis remain asymptomatic, with the infection localized in the lungs (primary pulmonary tuberculosis) or lymph nodes (primary lymph node tuberculosis).
• Mild Symptoms: Some children may experience mild symptoms, such as low-grade fever, cough, fatigue, and loss of appetite.

1. Complications of Primary Tuberculosis:

• Progression to Active Disease: In some cases, primary tuberculosis can progress to active disease, particularly in children with weakened immune systems or underlying health conditions.
• Extrapulmonary Involvement: Primary tuberculosis can also lead to extrapulmonary manifestations, such as tuberculous meningitis, miliary tuberculosis, or disseminated tuberculosis affecting multiple organs.

1. Post-primary Tuberculosis (Reactivation TB):

• Symptoms: Older children and adolescents may develop symptoms of post-primary tuberculosis (reactivation TB), including persistent cough, hemoptysis, chest pain, weight loss, night sweats, and fatigue.
• Pulmonary and Extrapulmonary Involvement: Post-primary tuberculosis commonly involves the lungs but can also affect other organs, such as the lymph nodes, bones, joints, kidneys, or central nervous system.

Diagnostic Approach for Tuberculosis in Children:

1. Clinical Evaluation:

• Medical History: Inquire about symptoms, exposure to individuals with tuberculosis, travel history, and previous tuberculosis screening or treatment.
• Physical Examination: Perform a thorough physical examination, including assessment of respiratory symptoms, lymphadenopathy, growth parameters, and signs of extrapulmonary involvement.

1. Tuberculin Skin Test (TST):

• Mantoux Test: Administer a tuberculin skin test (Mantoux test) by intradermal injection of purified protein derivative (PPD) tuberculin. Interpret the induration reaction measured 48-72 hours later. A positive reaction indicates exposure to tuberculosis but does not differentiate between active infection and latent infection.

1. Interferon-Gamma Release Assays (IGRAs):

• Blood Test: Perform interferon-gamma release assays (IGRAs), such as the QuantiFERON-TB Gold In-Tube (QFT-GIT) or T-SPOT.TB test, to detect immune response to M. tuberculosis antigens. IGRAs may be preferred over TST in children who have received Bacillus Calmette-Guérin (BCG) vaccination or have difficulty returning for TST reading.

1. Chest X-ray:

• Imaging Study: Obtain a chest X-ray to evaluate for pulmonary abnormalities suggestive of tuberculosis, such as parenchymal infiltrates, hilar lymphadenopathy, or cavitations.
• Considerations: Chest X-ray findings may vary widely in children with tuberculosis, ranging from normal to extensive lung involvement.

1. Microbiological Tests:

• Sputum Examination: Collect sputum samples for acid-fast bacilli (AFB) smear microscopy and mycobacterial culture. However, obtaining sputum samples can be challenging in young children, particularly those unable to expectorate effectively.
• Gastric Aspirates: Perform gastric aspirates or induced sputum in young children unable to produce sputum spontaneously.

1. Other Investigations (if indicated):

• Biopsy: Consider lymph node biopsy or other tissue sampling for histopathological examination and mycobacterial culture in cases of suspected extrapulmonary tuberculosis.
• Laboratory Tests: Perform complete blood count (CBC), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), liver function tests, and renal function tests to assess for systemic inflammation or organ dysfunction.

Treatment of Tuberculosis in Children:

1. Antitubercular Therapy (ATT):

• Drug Regimen: Initiate multidrug antitubercular therapy consisting of isoniazid (INH), rifampicin (RIF), pyrazinamide (PZA), and ethambutol (EMB) for the initial intensive phase, followed by INH and RIF for the continuation phase.
• Duration: Administer antitubercular therapy for a total duration of 6-9 months, depending on the child’s age, severity of disease, and treatment response.

1. Directly Observed Therapy (DOT):

• Supervised Treatment: Ensure adherence to antitubercular therapy through directly observed therapy (DOT), where healthcare providers or trained observers directly observe and document medication intake by the child.

1. Monitoring and Follow-Up:

• Clinical Evaluation: Monitor the child’s clinical response to treatment, including resolution of symptoms, improvement in radiological findings, and normalization of laboratory parameters.
• Regular Follow-Up: Schedule regular follow-up visits to assess treatment adherence, monitor for adverse effects, and adjust treatment as needed.

1. Contact Screening and Prophylaxis:

• Contact Investigation: Perform contact screening of household contacts and close contacts of the index case to identify individuals at risk of tuberculosis exposure or infection.
• Prophylactic Treatment: Consider administering isoniazid preventive therapy (IPT) to high-risk contacts, such as young children <5 years of age or individuals with HIV infection, to prevent progression to active tuberculosis.

Summary:

Tuberculosis in children presents with diverse clinical manifestations, ranging from asymptomatic infection to severe disease with extrapulmonary involvement. The diagnostic approach includes a combination of clinical evaluation, tuberculin skin testing, interferon-gamma release assays, chest X-ray, microbiological tests, and other investigations as indicated. Treatment involves multidrug antitubercular therapy administered under directly observed therapy, with close monitoring of treatment response and adherence. Contact screening and prophylactic treatment may be necessary to prevent tuberculosis transmission and progression in high-risk individuals. Early diagnosis and prompt initiation of treatment are critical for successful management and prevention of tuberculosis-related morbidity and mortality in children.