Fellow's quick read · Infectious Disease
Tuberculosis treatment
ATS/CDC/ERS/IDSA 2024 update · standard-of-care backbone from ATS/CDC/IDSA 2016 · reviewed 2026-07-08
Personal study digest for a new ID fellow. The 2024 document is a targeted update — it answers only four questions (a 4-month drug-susceptible regimen for adults, a 4-month regimen for children with nonsevere disease, and 6-month BPaL/BPaLM for drug-resistant TB). Everything else here — the standard RIPE backbone, durations, monitoring, extrapulmonary disease, HIV, steroids — is still governed by the 2016 ATS/CDC/IDSA drug-susceptible-TB guideline. The "What's changed" box is reviewer synthesis of newer evidence, each item cited; not the guideline. Confirm doses and drug-susceptibility before you prescribe.
In one line
TB treatment is now shorter and increasingly all-oral: standard drug-susceptible pulmonary TB is still 6 months of RIPE, but eligible adults can take a 4-month rifapentine–moxifloxacin regimen, children with nonsevere disease get 4 months, and multidrug/rifampin-resistant TB collapses from 15–24 months to a 6-month BPaLM (or BPaL) regimen. Drug-susceptibility testing chooses the regimen — get it early.
When to suspect / what drives the regimen
- Confirm and phenotype before committing. Send AFB smear, culture, and a rapid molecular test; the choice between a susceptible-TB regimen and a resistant-TB regimen turns on rifampin (and, for BPaL vs BPaLM, fluoroquinolone) susceptibility. Start empiric RIPE while results are pending in almost every suspected active case.
- Every active case is treated as multidrug therapy — single-drug TB treatment breeds resistance. Never add one drug to a failing regimen.
- TB is reportable; involve public health / the CDC-funded regional TB centers for complicated or drug-resistant cases.
Workup the fellow drives
- Baseline: drug-susceptibility testing, HIV test (mandatory), hepatitis B/C serologies, baseline LFTs, CBC/creatinine, and visual acuity + color vision if ethambutol is used.
- Before a QT-prolonging regimen (4-month HPZM, BPaL, BPaLM): baseline ECG and reconcile other QT drugs; moxifloxacin and bedaquiline both prolong QT.
- Give pyridoxine (vitamin B6) 25–50 mg/day with isoniazid to prevent peripheral neuropathy.
- Monitor for drug-induced liver injury: stop hepatotoxic drugs if ALT ≥3× ULN with hepatitis symptoms, or ≥5× ULN without symptoms.
Regimens
| Scenario | Drugs | Duration | Strength |
|---|---|---|---|
| Standard drug-susceptible pulmonary TB (adult) | Isoniazid + Rifampin + Pyrazinamide + Ethambutol (RIPE), then Isoniazid + Rifampin | 2 mo RIPE + 4 mo INH/RIF = 6 mo | Standard (2016) |
| NEW 4-month option, DS pulmonary TB, age ≥12 | Isoniazid 300 + rifaPENTINE 1,200 + MOXIfloxacin 400 mg daily (×17 wk) + Pyrazinamide (×8 wk) — 2HPZM/2HPM | 4 mo (17 wk) | Conditional, moderate (2024) |
| Children 3 mo–16 y, NONSEVERE DS-TB | INH + RIF + PZA (± EMB) ×8 wk → INH + RIF ×8 wk — 2HRZ(E)/2HR | 4 mo | Strong, moderate (2024) |
| MDR/RR-TB, fluoroquinolone-SUSCEPTIBLE, age ≥14 | BPaLM = Bedaquiline + Pretomanid + Linezolid 600 + Moxifloxacin | 6 mo (26 wk) | Strong, very low (2024) |
| RR-TB, fluoroquinolone-RESISTANT / intolerant, age ≥14 | BPaL = Bedaquiline + Pretomanid + Linezolid 600 (drop the moxifloxacin) | 6 mo (26 wk) | Strong, very low (2024) |
| TB meningitis | RIPE ×2 mo → INH/RIF ×7–10 mo + adjunctive dexamethasone/prednisolone tapered over 6–8 wk | 9–12 mo | Steroids strong (2016) |
Dosing detail: bedaquiline 400 mg daily ×2 wk, then 200 mg three times weekly ×24 wk; pretomanid 200 mg and linezolid 600 mg daily ×26 wk. Pyrazinamide in the adult 4-month regimen is weight-banded (40–<55 kg 1,000 mg; 55–75 kg 1,500 mg; >75 kg 2,000 mg). All regimens 7 days/week with food; give with DOT 5 of 7 days.
Key decisions a fellow owns
- Is the patient eligible for the 4-month HPZM regimen? Needs isoniazid- and rifampin-susceptible pulmonary TB, age ≥12. Excluded: extrapulmonary TB (CNS, bone/joint, miliary), pregnancy/breastfeeding, and known prolonged QT.
- BPaLM vs BPaL is decided by the fluoroquinolone. FQ-susceptible → keep the moxifloxacin (BPaLM). FQ-resistant/intolerant → drop it (BPaL). Both require age ≥14 and no prior exposure (or <1 month) to bedaquiline or linezolid.
- Anticipate linezolid toxicity. Peripheral neuropathy, optic neuritis, and myelosuppression are the dose-limiting problems — monitor CBC and for neuropathy, and reduce/interrupt linezolid rather than abandon the regimen.
- Extend to 9 months when a drug-susceptible pulmonary case has both cavitation on the initial film and a positive culture at the end of the 2-month intensive phase (relapse ~20% vs ~2%).
- HIV: treat TB with the standard regimen and start ART during treatment (early if CD4 low); watch rifamycin–antiretroviral interactions and paradoxical/IRIS worsening.
- Use DOT; escalate to health-department/expert consultation for drug resistance, treatment failure, or intolerance.
Special populations
- Pregnancy: standard RIPE is used; the newer short regimens are not — the 4-month HPZM regimen excludes pregnancy, and pretomanid (BPaL/BPaLM) and moxifloxacin are avoided. A delamanid-based regimen is the resistant-TB alternative in pregnancy/children.
- HIV not on ART (uncommon): extend the continuation phase by 3 months (total 9 months) for drug-susceptible pulmonary TB.
- Hepatic disease / DILI: isoniazid, rifampin, and pyrazinamide are the hepatotoxic three — hold all three at the ALT thresholds above and rechallenge carefully.
- TB pericarditis: adjunctive corticosteroids are not routinely recommended (contrast with meningitis, where they are).
Duration & stopping
- Drug-susceptible pulmonary TB: 6 months standard; 9 months if cavitary + 2-month culture-positive. Smear- and culture-negative pulmonary TB: 4 months may suffice.
- Eligible adults: the 4-month HPZM regimen. Children with nonsevere disease: 4 months.
- MDR/RR-TB (BPaLM or BPaL): 6 months — a dramatic shortening from the old 15–24-month regimens.
- TB meningitis: 9–12 months; bone/joint and other high-relapse sites are extended per the 2016 guideline.
What's changed since 2024
Reviewer synthesis — not the guideline. The 2024 update is recent, so most of this reinforces or extends it.
- The 2024 document is a targeted update, not a full replacement. It answers only the four regimen questions above; the 2016 ATS/CDC/IDSA guideline still governs the RIPE backbone, monitoring, extrapulmonary durations, HIV, and steroids. Don't read it as a standalone treatment manual. Saukkonen, Am J Respir Crit Care Med 2025;211:15–33; DOI 10.1164/rccm.202410-2096ST · Nahid, Clin Infect Dis 2016;63:e147–e195, DOI 10.1093/cid/ciw376
- More all-oral options for MDR/RR-TB are arriving beyond BPaLM. The endTB trial tested five 9-month all-oral bedaquiline/delamanid-containing regimens and found three noninferior to the standard of care — giving alternatives to pretomanid-based BPaLM (relevant where pretomanid is unavailable or contraindicated). endTB, N Engl J Med 2025; DOI 10.1056/NEJMoa2400327 · PMID 39879593
- For pre-XDR (fluoroquinolone-resistant) TB, a delamanid-clofazimine regimen fell short of formal noninferiority but gave excellent outcomes in limited disease — the shorter-course frontier for the hardest cases. endTB-Q (BDLC), Lancet Respir Med 2025; DOI 10.1016/S2213-2600(25)00194-8
- Delamanid substitutes for pretomanid in children and pregnancy. Pretomanid (hence BPaL/BPaLM) is not established <14 y or in pregnancy/breastfeeding; bedaquiline–delamanid–linezolid–based regimens fill that gap. BEAT-Tuberculosis, N Engl J Med 2026 (reviewer note; corroborates endTB)
- Alignment with WHO and CDC is intact. The guideline adopted the WHO 2022 recommendations by GRADE-ADOLOPMENT; WHO's Aug-2024 rapid communication and 2025 consolidated guidance keep 6-month BPaLM/BPaL prioritized for eligible DR-TB, and CDC endorsed the update (2025 Dear Colleague Letter). who.int rapid communication 23 Aug 2024 · cdc.gov/tb 2025 treatment guidelines
- Implementation caveats on the 4-month adult regimen. It hinges on rifapentine (cost/supply; FDA nitrosamine advisory) plus moxifloxacin (QT, dysglycemia), and excludes extrapulmonary TB and pregnancy — a published "word of caution" urges careful patient selection; real-world efficacy has been shown in persons with diabetes. Emerg Infect Dis 2025;31(3) · commentary, Am J Respir Crit Care Med 2025 (PMC12369876)
Anki cards minted this run
- BPaLM vs BPaL discriminator — the fluoroquinolone decides the "M" (TB-PRACTECAL).
- ZeNix linezolid 600 mg × 26 wk — the optimized BPaL dose vs the original 1,200 mg.
- 4-month HPZM exclusions — not for CNS/bone/miliary TB, pregnancy, or prolonged QT (Study 31/A5349).
- Pediatric nonsevere 4-month TB — SHINE, and the definition of "nonsevere."
Held: the adult 4-month HPZM regimen itself and BPaL (NIX-TB) are already in the deck; an endTB/BDL currency card overlaps the existing BEAT-TB card — held under cap.
Sources: Saukkonen JJ et al. Updates on the Treatment of Drug-Susceptible and Drug-Resistant Tuberculosis (ATS/CDC/ERS/IDSA). Am J Respir Crit Care Med 2025;211(1):15–33, DOI 10.1164/rccm.202410-2096ST. · Nahid P et al. Treatment of Drug-Susceptible Tuberculosis (ATS/CDC/IDSA). Clin Infect Dis 2016;63:e147–e195, DOI 10.1093/cid/ciw376. · Study 31/A5349: Dorman SE et al. Four-Month Rifapentine Regimens with or without Moxifloxacin for Tuberculosis. N Engl J Med 2021;384:1705–1718, DOI 10.1056/NEJMoa2033400, PMID 33951360. · SHINE: Turkova A et al. Shorter Treatment for Nonsevere Tuberculosis in African and Indian Children. N Engl J Med 2022;386:911–922, DOI 10.1056/NEJMoa2104535, PMID 35263517. · ZeNix: Conradie F et al. Bedaquiline–Pretomanid–Linezolid Regimens for Drug-Resistant Tuberculosis. N Engl J Med 2022;387:810–823, DOI 10.1056/NEJMoa2119430, PMID 36053506. · TB-PRACTECAL: Nyang'wa B-T et al. A 24-Week, All-Oral Regimen for Rifampin-Resistant Tuberculosis. N Engl J Med 2022;387:2331–2343, DOI 10.1056/NEJMoa2117166, PMID 36546625. · endTB: N Engl J Med 2025, DOI 10.1056/NEJMoa2400327, PMID 39879593. · endTB-Q: Lancet Respir Med 2025, DOI 10.1016/S2213-2600(25)00194-8. Currency layer also drew on WHO (rapid communication 23 Aug 2024; 2025 consolidated guidance) and CDC 2025 treatment guidelines. Full text of the primary trials was not pulled into the journal archive this run (unattended; needs a logged-in Chrome session).