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

Treatment of TB Ileitis

TB ileitis should be treated with the same standard 6-month regimen used for pulmonary tuberculosis: 2 months of isoniazid, rifampin, pyrazinamide, and ethambutol (2HRZE), followed by 4 months of isoniazid and rifampin (4HR). 1, 2

Standard Treatment Regimen

The treatment approach for TB ileitis follows the same principles as pulmonary TB, as extrapulmonary tuberculosis (including gastrointestinal involvement) responds equally well to standard short-course chemotherapy 1, 2.

Initial Phase (2 months)

• Isoniazid: 5 mg/kg daily (maximum 300 mg) 1, 2
• Rifampin: 10 mg/kg daily (450 mg if <50 kg; 600 mg if ≥50 kg) 1, 2
• Pyrazinamide: 35 mg/kg daily (1.5 g if <50 kg; 2.0 g if ≥50 kg) 1, 2
• Ethambutol: 15 mg/kg daily 1, 2

Continuation Phase (4 months)

• Isoniazid: 5 mg/kg daily (maximum 300 mg) 1, 2
• Rifampin: 10 mg/kg daily (450 mg if <50 kg; 600 mg if ≥50 kg) 1, 2

Evidence Supporting 6-Month Duration

A Cochrane systematic review specifically evaluated treatment duration for abdominal TB (including intestinal and peritoneal TB) and found no evidence that 6-month regimens are inadequate compared to 9-month regimens 3. Relapse was uncommon in both groups (2/140 in 6-month group vs 0/129 in 9-month group), and clinical cure rates were equivalent (RR 1.02,95% CI 0.97-1.08) 3. This supports using the standard 6-month regimen rather than extending treatment unnecessarily.

When to Omit Ethambutol

Ethambutol can be omitted in the initial phase for patients at low risk of isoniazid resistance 1, 2:

• Previously untreated patients
• HIV-negative patients
• No known contact with drug-resistant TB
• Living in areas with isoniazid resistance rates <4% 2

However, if drug susceptibility results are not immediately available or resistance risk is uncertain, include all four drugs initially. 1

When to Extend Treatment Duration

Extend treatment to 9 months total (2HRZE/7HR) only if pyrazinamide cannot be included in the initial regimen due to contraindications or intolerance 1, 2. The standard 6-month regimen is otherwise sufficient for TB ileitis 3.

Directly Observed Therapy (DOT)

All patients with active TB, including TB ileitis, should receive directly observed therapy to ensure adherence and prevent treatment failure and drug resistance 1, 2. If universal DOT is not feasible, prioritize it for high-risk patients (those with drug-resistant disease, substance use disorders, homelessness, or history of nonadherence) 1.

Special Populations

HIV Co-infection

• Use the same 6-month regimen 1, 2
• Add pyridoxine (vitamin B6) 25-50 mg daily to prevent isoniazid-related neuropathy 2
• Avoid once-weekly isoniazid-rifapentine regimens in HIV-positive patients 1
• Monitor for drug interactions between rifampin and antiretroviral therapy 1

Pregnancy

• All first-line drugs (isoniazid, rifampin, pyrazinamide, ethambutol) are safe in pregnancy 1
• Avoid streptomycin due to fetal ototoxicity 1
• Add pyridoxine 10 mg daily 4

Pre-existing Liver Disease

• If liver enzymes are normal at baseline, use the standard regimen with frequent monitoring 1, 4
• Consider alternative regimens if severe hepatic impairment exists 5

Renal Insufficiency

• Adjust ethambutol dosing based on creatinine clearance 1, 4
• Administer medications after hemodialysis to avoid premature drug removal 1

Drug-Resistant TB Ileitis

Isoniazid-Resistant TB

Add a later-generation fluoroquinolone (levofloxacin or moxifloxacin) to a 6-month regimen of rifampin, ethambutol, and pyrazinamide 1, 2. Pyrazinamide duration may be shortened to 2 months in selected cases with noncavitary or lower-burden disease 1.

Multidrug-Resistant TB (MDR-TB)

• Requires individualized regimens based on drug susceptibility testing 1, 4
• Refer to specialized MDR-TB treatment centers 4
• Use at least 5 effective drugs in the intensive phase and 4 in the continuation phase 1

Monitoring Response to Treatment

• Assess clinical symptoms monthly 1, 2
• Monitor for adverse drug reactions, particularly hepatotoxicity 1, 2
• If clinical improvement does not occur within 2-3 months, consider drug resistance or nonadherence 1

Common Pitfalls and Caveats

• Do not confuse the 6-month regimen for active TB with shorter 3-4 month rifamycin-based regimens for latent TB infection 1, 2
• Rifampin significantly interacts with many medications including oral contraceptives, anticoagulants, and antiretroviral drugs—review all medications and adjust doses accordingly 2
• Do not use 2 months of rifampin plus pyrazinamide for latent TB due to hepatotoxicity risk, though this combination is appropriate as part of the 4-drug regimen for active disease 1
• Malabsorption concerns in gastrointestinal TB have not been shown to require treatment extension beyond 6 months 3
• Report all TB cases promptly to local public health authorities for contact tracing and surveillance 1