What is the recommended treatment for Tuberculosis (TB) lymphadenitis?

Treatment of Tuberculous Lymphadenitis

The recommended treatment for tuberculous lymphadenitis is a 6-month regimen consisting of isoniazid, rifampin, pyrazinamide, and ethambutol for the initial 2 months, followed by isoniazid and rifampin for an additional 4 months (2HRZE/4HR). 1

First-Line Treatment Regimen

• The standard treatment for tuberculous lymphadenitis follows the same principles as pulmonary tuberculosis, with a 6-month regimen consisting of four drugs initially, followed by two drugs for the continuation phase 1
• Standard adult dosing includes:
  • Isoniazid: 5 mg/kg (up to 300 mg) daily 1, 2
  • Rifampin: 10 mg/kg (450 mg if <50 kg, 600 mg if >50 kg) daily 1, 3
  • Pyrazinamide: 35 mg/kg (1.5 g if <50 kg, 2.0 g if >50 kg) daily 1, 4
  • Ethambutol: 15 mg/kg daily 1

Treatment Considerations

• Ethambutol may be omitted in patients with a low risk of isoniazid resistance (isoniazid resistance rate <4%) and in previously untreated patients who are HIV-negative 1, 3
• Drug susceptibility testing should be performed on initially isolated organisms to guide therapy if resistance is detected 2
• Directly observed therapy (DOT) is recommended to ensure treatment adherence, particularly for intermittent regimens 1, 2
• If pyrazinamide cannot be included in the initial regimen, treatment duration should be extended to 9 months total 3, 5

Special Populations

HIV Co-infection

• For HIV-infected patients with tuberculous lymphadenitis, the same 6-month regimen is recommended, but clinical and bacteriologic response must be carefully assessed 1, 6
• If there is evidence of a slow or suboptimal response in HIV-infected patients, therapy should be prolonged on a case-by-case basis 6
• Pyridoxine (vitamin B6, 25-50 mg daily) should be administered to all HIV-infected patients receiving isoniazid to prevent neurological side effects 3

Children

• For children, dosing should be weight-based, with isoniazid at 10-15 mg/kg (up to 300 mg) daily 1, 2
• The same 6-month regimen is recommended for children with tuberculous lymphadenitis 1, 6

Management of Drug Resistance

• For isoniazid-resistant tuberculous lymphadenitis, the American Thoracic Society recommends adding a later-generation fluoroquinolone to a 6-month regimen of daily rifampin, ethambutol, and pyrazinamide 1
• For multidrug-resistant TB (MDR-TB), which includes resistance to at least isoniazid and rifampin, treatment must be individualized based on susceptibility studies 7, 6
• The American Thoracic Society recommends at least five drugs in the intensive phase and four drugs in the continuation phase for MDR-TB treatment 7

Monitoring and Follow-up

• Patients should be monitored monthly for treatment response and adverse effects 1
• Nodes can appear afresh or enlarge during treatment but usually resolve without additional intervention 5
• Approximately 10% of patients may be left with residual nodes at the end of chemotherapy, which does not necessarily indicate treatment failure or require additional intervention 5

Common Pitfalls and Caveats

• Shorter rifamycin-based regimens (3-4 months) that are now preferred for latent TB infection should not be confused with the 6-month regimen required for active tuberculous lymphadenitis 1
• Rifampin interacts with many medications, including oral contraceptives, anticoagulants, and antiretroviral drugs, requiring careful medication review and potential dose adjustments 3
• Surgical procedures should be reserved for the relief of discomfort caused by enlarged nodes or tense, fluctuant nodes, rather than as primary treatment 5
• Nodes that enlarge or appear after completion of therapy do not necessarily indicate relapse and often resolve spontaneously 5