Drug-Resistant TB

Isoniazid Monoresistant TB

Rifampicin resistant, Pre-XDR and XDR TB

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ISONIAZID MONORESISTANT TB

A15.0-9/A16.0-5/A16.7-9/A17.0-1/A17.8-9/A18.0-8/A19.0-2/A19.8-9 + (B20.0) + (U50.00-01/U50.10-11)

• Isoniazid monoresistant TB is TB disease caused by M. tuberculosis complex that is resistant to isoniazid but susceptible to rifampicin.

MEDICINE TREATMENT

Confirmed INH monoresistant TB:

• RHZE at standard dosing,

AND

• Levofloxacin, oral, daily:
  • 30–45 kg: 750 mg
  • ≥46 kg: 1000 mg

Confirmed isoniazid monoresistant TB AND contraindication to isoniazid:

• Rifampicin, oral, 10 mg/kg daily.

AND

• Ethambutol, oral, 15 mg/kg daily.

AND

• Pyrazinamide, oral, 25 mg/kg daily.

AND

• Levofloxacin, oral, daily:
  • 30–45kg: 750 mg
  • ≥46kg: 1000 mg

Treatment should be given for at least 6 months.

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RIFAMPICIN RESISTANT, Pre-XDR and XDR TB

A15.0-9/A15.7-8/A16.0-5/A16.7-9/A17.0-1/A17.8-9/A18.0-7/A18.8/A19.0-2/ A19.8-9 + (B20.0) + (U50.00-01/U50.20-21/U50.30-31)

Never treat for drug-resistant TB without laboratory confirmation, either by molecular or phenotypic (culture and sensitivity) results.

DESCRIPTION

• Rifampicin resistant tuberculosis (RR-TB) is diagnosed when there is resistance of M. tuberculosis to rifampicin, with or without resistance to other anti-TB drugs.
• RR-TB is diagnosed exclusively on culture and sensitivity assays or TB nucleic acid amplification tests (TB-NAAT). While some TB-NAAT assays test for both rifampicin and isoniazid resistance, Xpert® MTB/RIF Ultra, a type of TB-NAAT, only tests for rifampicin resistance.
• However, rifampicin resistance detected by Xpert® MTB/RIF Ultra is sufficient to start a patient on RR treatment, pending confirmation of RR-TB by line probe assay.
• Pre XDR-TB is TB disease caused by a strain of M. tuberculosis that is resistant to rifampicin (with or without INH resistance) and at least one fluoroquinolone (either levofloxacin or moxifloxacin).
• Extensively drug-resistant TB (XDR-TB) is TB disease caused by a strain of M. tuberculosis that is resistant to rifampicin AND at least one fluoroquinolone (levofloxacin or moxifloxacin) AND either bedaquiline or linezolid.
• Confirmation of pre XDR- and XDR-TB requires line probe assay and drug susceptibility testing.

GENERAL MEASURES

• Screen all close contacts for signs and symptoms to detect early disease.

MEDICINE TREATMENT

Drug resistant TB prophylaxis

• The effectiveness of preventive therapy in adults exposed to drug resistant TB bacteria is not currently known. Consult a specialist for management.

RR-TB and Pre XDR-TB treatment

• Consult the most recent national drug resistant TB programme guidelines. Treatment for 6–18 months is required.

LoE:IVbI^li

• Management of drug resistant TB should be conducted in dedicated drug resistant TB clinics and hospitals with appropriate infection control measures.

XDR-TB treatment

• Patients with XDR-TB should be discussed with the National Clinical Advisory Committee (Email: NCAC@witshealth.co.za) and referred to a TB hospital for an individualised regimen of at least 4 effective medicines, based on susceptibility tests and treatment history.
• Infection control to prevent airborne transmission is essential to prevent nosocomial transmission.

Click here to access the pdf.

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Standard Treatment Guidelines and Essential Medicines List for South Africa, Adult Hospital Level, 2020-2024_Version 1.1_16 September 2024 

Chapter 16: Respiratory Disorders _16.11 Drug-Resistant TB