This handbook serves as a practical companion to the WHO Consolidated Guidelines on Drug-Resistant Tuberculosis. While the guidelines provide the policy recommendations, this document focuses on the operational aspects of implementation. It is designed for national tuberculosis programs (NTPs), health care providers, and stakeholders involved in the management of drug-resistant tuberculosis (DR-TB). The primary objective is to facilitate the transition from older, injection-based regimens to newer, fully oral regimens that are shorter, more effective, and less toxic.
1. Introduction and Scope
The management of drug-resistant TB has undergone a paradigm shift over the last decade. The introduction of new drugs and regimens has radically improved treatment outcomes and patient quality of life. This handbook operationalizes the latest evidence, providing clinical algorithms, monitoring schedules, and practical advice for clinicians at the bedside.
It addresses the entire cascade of care: from diagnosis and registration to treatment initiation, monitoring for adverse events, and post-treatment follow-up. The content emphasizes a patient-centered approach, aiming to decentralize care where possible to bring treatment closer to the community.
2. Diagnosis and Treatment Eligibility
Prompt and accurate diagnosis is the cornerstone of effective DR-TB management. The handbook recommends the use of rapid molecular diagnostic tests as the initial test for all individuals with signs and symptoms of TB.
Rapid Molecular Diagnostics
WHO recommends the use of WHO-recommended rapid molecular diagnostics (WRDs), such as Xpert MTB/RIF and Xpert MTB/XDR, or Truenat assays. These tests simultaneously detect Mycobacterium tuberculosis complex and mutations associated with rifampicin resistance, which is a proxy for multidrug-resistant TB (MDR-TB). Further testing for resistance to fluoroquinolones and injectable agents is critical to determine the appropriate regimen.
Key Recommendation
Universal drug susceptibility testing (DST) should be performed for all patients diagnosed with TB. For DR-TB patients, DST should be used to guide the selection of the most effective oral regimen.
3. All-oral Treatment Regimens
The most significant change in recent years is the recommendation of all-oral regimens for the treatment of MDR/RR-TB. The use of injectable agents (aminoglycosides) is no longer recommended for routineDR-TB treatment due to high toxicity and poor efficacy compared to oral options.
The BPaLM Regimen
For patients with MDR/RR-TB who are not resistant to fluoroquinolones, a 6-month regimen consisting of Bedaquiline, Pretomanid, Linezolid, and Moxifloxacin (BPaLM) is recommended. This regimen offers high efficacy and a significantly shorter duration compared to previous treatments.
- Bedaquiline: Taken for 6 months.
- Pretomanid: Taken for 6 months.
- Linezolid: Taken for 6 months.
- Moxifloxacin: Taken for 6 months.
The 9-Month All-Oral Regimen
For patients who may not be eligible for the BPaLM regimen (e.g., due to fluoroquinolone resistance or unavailability of pretomanid), a 9-month all-oral regimen is an alternative. This typically includes Bedaquiline, Linezolid, and other Group 2 and 3 drugs (such as Clofazimine) based on susceptibility.
Individualized longer regimens (18-20 months) remain an option for patients with extensive resistance patterns or those who have failed previous regimens, utilizing the best selection of drugs based on DST results.
4. Monitoring and Adverse Events
Active pharmacovigilance is essential when using new DR-TB drugs. While all-oral regimens are better tolerated, they can still cause serious side effects that require timely intervention.
Monitoring for Linezolid Toxicity
Linezolid is a potent drug but carries risks of hematological toxicity (anemia, leukopenia, thrombocytopenia) and peripheral neuropathy. Patients should have weekly blood tests for the first month, and then monthly.
Clinical Action
If a patient develops symptoms of neuropathy (numbness, tingling, pain in hands or feet) or significant anemia, the dosage of Linezolid may need to be reduced (e.g., from 600mg to 300mg) or temporarily interrupted.
QTc Prolongation
Bedaquiline, Clofazimine, and Delamanid can prolong the QTc interval, potentially leading to cardiac arrhythmias. A baseline Electrocardiogram (ECG) is mandatory. Follow-up ECGs should be performed at least monthly. Concomitant use of other QT-prolonging drugs should be avoided or managed carefully.
5. Models of Care and Support
Successful treatment outcomes depend not only on the right drugs but also on the right model of care. The handbook strongly advocates for the decentralization of DR-TB treatment.
Decentralized Care
Initiating treatment at a peripheral level, closer to the patient's home, reduces the financial and social burden associated with travel to specialized referral centers. This requires training of general health workers and ensuring a reliable supply chain for medicines.
Patient Support
Adherence support is vital. Treatment should be administered using patient-centered care models, including digital adherence technologies (video-supported treatment, medication monitors), counseling, and psychosocial support. Family support and community engagement play critical roles in ensuring the patient completes the 6 to 9 month course.
6. Infection Prevention and Control
Preventing the transmission of M. tuberculosis within health care facilities is a critical component of programmatic management.
- Administrative Controls: Triage and fast-track patients with cough symptoms to minimize waiting times.
- Environmental Controls: Ensure natural ventilation in wards and clinics. Use upper-room ultraviolet germicidal irradiation (UVGI) where natural ventilation is insufficient.
- Respiratory Protection: Health workers should fit-tested N95 respirators when working with suspected or confirmed infectious DR-TB patients. Patients should wear surgical masks when moving through common areas.
7. Conclusion
The implementation of the WHO guidelines for DR-TB represents a historic opportunity to improve the prognosis for millions of patients affected by this disease. By adopting shorter, highly effective all-oral regimens and integrating them into strong patient-centered health systems, national programs can drastically improve cure rates while minimizing suffering. The transition requires commitment to training, pharmacovigilance, and supply chain management, but the outcomehealth equity and the elimination of TBis a goal worth pursuing.
