Tuberculosis (TB) in children, caused by Mycobacterium tuberculosis, accounts for an estimated 11% of global TB cases—about 1 million children annually with 200,000 deaths, the majority in low- and middle-income countries. Pediatric TB differs from adult disease in several key respects: paucibacillary disease (low organism burden, harder to confirm microbiologically), more rapid progression from infection to disease, higher rates of extrapulmonary involvement (25-30% versus 15% in adults), greater susceptibility to disseminated forms (TB meningitis, miliary TB) particularly in infants and young children, and higher rates of severe disease and death without treatment.
Clinical presentations: pulmonary TB (most common, with primary complex of Ghon focus and hilar lymphadenopathy on chest X-ray, persistent cough >2-3 weeks, weight loss/failure to thrive, fever, night sweats); TB meningitis (most feared form, presents with subacute fever, irritability, lethargy progressing to seizures, cranial nerve palsies, decreased consciousness; CSF lymphocytic pleocytosis with elevated protein and low glucose; brain imaging shows basal meningeal enhancement, hydrocephalus, infarcts; mortality 20-30%, neurologic sequelae 50% if delayed diagnosis); miliary TB (hematogenous dissemination with multi-organ involvement, classic miliary chest imaging); TB lymphadenitis (most common extrapulmonary form, cervical scrofula); abdominal TB (peritoneal, intestinal, mesenteric lymphadenopathy); bone and joint TB (Pott disease, dactylitis); congenital TB (rare, transplacental or intrapartum transmission).
Diagnosis: thorough contact history (exposure to active TB case is critical), tuberculin skin test (TST positive ≥10 mm, or ≥5 mm in immunocompromised) or interferon-gamma release assay (IGRA, more specific in BCG-vaccinated, but lower sensitivity in young children), chest X-ray and possibly CT (lymphadenopathy, parenchymal disease, miliary pattern), Xpert MTB/RIF (rapid PCR with rifampin resistance, lower sensitivity than adults due to paucibacillary disease, requires gastric aspirate or induced sputum or stool in young children), mycobacterial culture (gold standard, takes 4-8 weeks), histology of biopsy specimens. Treatment: pulmonary TB and uncomplicated extrapulmonary—6-month regimen (2 months isoniazid+rifampin+pyrazinamide+ethambutol intensive phase; 4 months isoniazid+rifampin continuation); TB meningitis—12 months including ethambutol replaced by streptomycin or levofloxacin and corticosteroids; disseminated TB—9-12 months; multidrug-resistant TB—longer (9-20 months) with second-line drugs (bedaquiline, linezolid, levofloxacin/moxifloxacin, clofazimine). Preventive therapy: isoniazid 6-9 months for TB-exposed contacts (especially under 5), rifapentine+isoniazid weekly 3 months (3HP, ages ≥2). BCG vaccination prevents severe pediatric forms (miliary, meningitis) but not adult pulmonary disease.