What is the recommended treatment for a 16-year-old with tuberculosis (TB)?

Treatment of Tuberculosis in a 16-Year-Old

Standard First-Line Treatment Regimen

For a 16-year-old with drug-susceptible tuberculosis, treat with a 6-month regimen consisting of rifampin, isoniazid, pyrazinamide, and ethambutol for the first 2 months (intensive phase), followed by rifampin and isoniazid for 4 months (continuation phase). 1, 2

Intensive Phase (First 2 Months)

• Administer four drugs daily: 1, 3

  • Isoniazid: 10-15 mg/kg/day (maximum 300 mg daily) 1, 2
  • Rifampin: 10-20 mg/kg/day (maximum 600 mg daily) 1, 2
  • Pyrazinamide: 15-30 mg/kg/day (maximum 2 g daily) 1, 2
  • Ethambutol: 15-25 mg/kg/day (maximum 2.5 g daily) 1, 4

• Include ethambutol in the initial regimen until drug susceptibility results confirm the organism is fully susceptible to isoniazid and rifampin 1, 3

Continuation Phase (Months 3-6)

• Continue two drugs daily: 1, 3
  • Isoniazid: 10-15 mg/kg/day (maximum 300 mg daily) 1
  • Rifampin: 10-20 mg/kg/day (maximum 600 mg daily) 1

Critical Treatment Modifications Based on Disease Site

For TB Meningitis or CNS Involvement

• Extend total treatment duration to 12 months (not 6 months) with the same four-drug intensive phase for 2 months, followed by rifampin and isoniazid for 10 additional months 1
• Add adjunctive corticosteroids for moderate to severe TB meningitis 1

For Disseminated/Miliary TB

• Use the standard 6-month regimen unless CNS involvement is documented, in which case extend to 12 months 1
• Perform lumbar puncture in all cases of miliary TB to rule out meningeal involvement, as this determines whether 6-month or 12-month therapy is needed 4

Drug-Resistant TB Considerations

If Isoniazid-Resistant TB

• Treat with rifampin, pyrazinamide, and ethambutol for 6-12 months, adding a fluoroquinolone (levofloxacin 7.5-10 mg/kg/day or moxifloxacin 7.5-10 mg/kg/day) for extensive disease 1, 5

If Rifampin-Resistant TB

• Treat with isoniazid, pyrazinamide, ethambutol, and a fluoroquinolone for 12-15 months, with an injectable agent added for the first few months in cases of extensive disease 1

If Multidrug-Resistant (MDR) TB

• For adolescents aged 16 years, bedaquiline should be included in longer MDR-TB regimens (strong recommendation for patients ≥18 years, conditional recommendation for ages 6-17 years) 5
• Linezolid should be included in the treatment of MDR/RR-TB patients on longer regimens 5
• A fluoroquinolone (levofloxacin or moxifloxacin) should be included 5
• Do not use kanamycin or capreomycin in MDR-TB treatment 5
• Treatment typically lasts 18-24 months 1

Essential Monitoring and Safety Considerations

Baseline and Ongoing Monitoring

• Obtain baseline visual acuity testing using Snellen chart before starting ethambutol 4
• Perform monthly questioning about visual disturbances (blurred vision, scotomata, decreased red-green color discrimination) at each visit 4
• Recalculate drug dosages as the adolescent gains weight during treatment 1

Supplemental Medications

• Provide pyridoxine (vitamin B6) supplementation for malnourished adolescents or those with HIV infection to prevent isoniazid-induced peripheral neuropathy 1

Treatment Delivery and Adherence

• Directly observed therapy (DOT) is strongly recommended to ensure adherence throughout the entire treatment course 1, 6, 3
• All doses should be administered under direct observation, particularly during the intensive phase 7

Common Pitfalls to Avoid

• Do not stop ethambutol prematurely before drug susceptibility results confirm full susceptibility, even in adolescents where visual monitoring is feasible 1, 3
• Do not use a 6-month regimen for TB meningitis or CNS disease—these require 12 months of treatment 1
• Do not treat with fewer than four drugs initially if there is any possibility of drug resistance (>4% primary isoniazid resistance in the community, previous TB treatment, or exposure to a drug-resistant case) 3
• Do not use pyrazinamide beyond the initial 2-month intensive phase in standard drug-susceptible TB 2