12-phase flow (12)

1. 1FRAME
   Adult drug-SUSCEPTIBLE pulmonary TB + LTBI in the id.* family. Drug-resistant TB is OWNED by id.tb_drug_resistant.v1 — route there on Xpert-RIF+ or MDR contact. Pediatric TB and TB meningitis are out of scope (route to pediatric / neuro siblings). Place patient in airborne (negative-pressure, N95) isolation the moment active pulmonary TB is suspected (ATS/CDC/IDSA 2016 Nahid; WHO 2024)
   advance: Scope confirmed; airborne isolation initiated if active suspected
2. 2ENTRY
   Subacute cough ≥ 2–3 wk + constitutional symptoms (fever, night sweats, weight loss, hemoptysis), abnormal cavitary CXR, TB contact / endemic exposure, positive screening test (IGRA/TST), or HIV+ with any respiratory symptom (WHO 2024 — symptom-screen sensitivity lower in HIV)
   inputs: hiv_status
   advance: Entry trigger validated and public-health notification initiated
3. 3CONTEXT
   Document HIV status (+ CD4/VL if HIV+), prior TB / treatment, MDR/XDR contact, hepatic disease/alcohol/HBV/HCV, renal disease, pregnancy status, diabetes, baseline vision/color, current medications (rifampin DDI map: ART, anticoagulants, oral contraceptives, immunosuppressives, statins, anticonvulsants), birthplace / endemic country / incarceration / homelessness / HCW exposure (ATS/CDC/IDSA 2016 Nahid)
   inputs: hiv_status, prior_tb_or_treatment, mdr_xdr_contact_or_endemic_resistance, pregnancy_status, liver_disease_or_alcohol
   advance: Host + comorbidity + interaction map captured
4. 4RED_FLAGS
   Massive hemoptysis, miliary / disseminated TB, TB meningitis (route to neuro sibling), acute respiratory failure / ARDS, rifampin-resistance signal on Xpert (route id.tb_drug_resistant.v1), pregnancy with active disease, severe immunocompromise — emergent admission with negative-pressure isolation (ATS/CDC/IDSA 2016 Nahid; WHO 2024)
   inputs: cxr_pa_and_lateral
   advance: Emergent threats triaged + isolation in place
5. 5INITIAL_WORKUP
   Sputum × 3 (≥1 early-morning) for AFB smear + Xpert MTB/RIF Ultra + mycobacterial culture + phenotypic DST; CXR PA+lateral; MANDATORY HIV test; baseline LFT / Cr / CBC, HBV/HCV serology, glucose/A1c; baseline Snellen + Ishihara before ETB. Xpert Ultra rules in fast (sens ~88%, HIV+ ~90%) but trace-positive specificity ~96% — confirm with culture in low-prior patients; Xpert-RIF+ → route id.tb_drug_resistant.v1 (Dorman Lancet ID 2018 PMID 29198911)
   inputs: sputum_afb_smear_x3, sputum_xpert_mtb_rif_ultra, sputum_mycobacterial_culture_and_dst, cxr_pa_and_lateral, baseline_lft, baseline_creatinine, hiv_test
   actions: workup.tb, panel.lft, panel.cbc, panel.renal, panel.inflammation
   advance: Microbiology sent + HIV tested + isolation in place
6. 6BRANCHING_WORKUP
   CT chest if CXR equivocal or to distinguish malignancy / NTM / sarcoid pattern; bronchoscopy + BAL or induced sputum if smear-negative but pretest high; tissue / fluid Xpert + culture + histology for extrapulmonary disease; IGRA / TST for contacts; whole-genome sequencing for early resistance prediction; HIV CD4 + VL if newly diagnosed; HBV/HCV reflex (ATS/CDC/IDSA 2016 Nahid)
   advance: Targeted confirmatory tests obtained
7. 7DIFFERENTIAL
   Active pulmonary TB vs LTBI (IGRA/TST+ asymptomatic, normal CXR, micro-negative) vs NTM (non-cavitary bronchiectasis, repeated Xpert-neg AFB-pos) vs bacterial CAP / lung abscess (acute, lobar, β-lactam-responsive) vs lung cancer (mass, smoker, micro-neg) vs endemic fungal histo / cocci / blasto (travel, urine antigen) vs sarcoidosis (bilateral hilar adenopathy, non-caseating granulomas, micro-neg) vs lymphoma vs GPA. Pivots: Xpert Ultra sens/spec, AFB-smear sens, IGRA vs TST in BCG-vaccinated, CXR cavitation/upper-lobe distribution (ATS/CDC/IDSA 2016 Nahid; Dorman Lancet ID 2018 PMID 29198911)
   advance: Active TB vs LTBI vs alternative dx category assigned
8. 8RISK_STRATIFICATION
   Regimen-selection gate. Active DS-TB: standard 6-mo 2HRZE/4HR vs the 4-mo INH+rifapentine+moxifloxacin+PZA regimen (Dorman NEJM 2021 PMID 33951360 — eligible: age ≥12 yr, weight ≥40 kg, DS pulmonary TB, NOT severe / extensive cavitary disease, NOT pregnant, HIV acceptable if CD4 ≥100 on efavirenz-based ART). LTBI: 3HP (Sterling NEJM 2011 PMID 22150035) preferred vs 4R vs 3HR vs legacy 6–9H. Cavitary + month-2 culture-positive → extend continuation 7 mo (9-mo total). HIV / DM / extensive disease shift toward longer regimens (Nahid 2016 PMID 27516382)
   inputs: hiv_status, weight
   actions: calc.ckd_epi_2021
   advance: Active-vs-LTBI fork resolved + regimen phenotype chosen
9. 9TREATMENT
   DS-TB standard: 2-mo intensive RIPE (INH + RIF + PZA + ETB) → 4-mo INH+RIF continuation (drop ETB once DST confirms pan-susceptibility). DS-TB 4-mo alternative (Dorman 2021): INH + rifapentine 1200 + moxifloxacin 400 + PZA × 2 mo → rifapentine + moxi + INH × 2 mo (NON-INFERIOR). LTBI: 3HP (12 weekly doses INH + rifapentine, DOT preferred; SAT acceptable) preferred OR 4R OR 3HR OR 9H. Pyridoxine 25–50 mg/d MANDATORY with all INH-containing regimens. DOT (or video DOT) is standard for active disease; SAT only for select compliant low-risk patients. HIV: ART within 2 wk if CD4<50, within 8 wk otherwise; substitute rifabutin for rifampin when PI-based ART or some INSTI ART; integrase-inhibitor regimens (DTG, BIC) need rifabutin or rifampin-compatible dose adjustment per DHHS. Pregnancy: streptomycin contraindicated; INH+RIF+PZA+ETB acceptable. Adjunctive corticosteroids ONLY for TB meningitis (dexamethasone 0.4 mg/kg/d taper × 6–8 wk) or TB pericarditis (prednisolone per IMPI 2014) — NOT for routine pulmonary disease. DR-TB suspected/confirmed → route id.tb_drug_resistant.v1 (BPaL/BPaLM) (Nahid 2016 PMID 27516382; Dorman NEJM 2021 PMID 33951360; CDC LTBI 2020 Sterling)
   inputs: weight, baseline_lft, baseline_creatinine
   advance: Regimen + DOT + pyridoxine + ART-timing + adverse-effect plan documented
10. 10DISPOSITION
    Outpatient DOT if respiratory hygiene maintainable, no severe disease, public-health follow-up arranged, no high-risk susceptible household contacts (infants, HIV+, immunosuppressed). Admit with negative-pressure isolation for hemoptysis, miliary/meningeal/disseminated disease, severe immunocompromise, respiratory failure, rifampin-resistance with infection-control risk, or unworkable home-DOT plan (ATS/CDC/IDSA 2016 Nahid; WHO 2024)
    advance: Disposition + isolation + DOT plan + public-health reporting in place
11. 11MONITORING
    Sputum smear + culture monthly until 2 consecutive negative cultures (month-2 culture is the key conversion endpoint; positive at 2 mo with cavitation → extend continuation to 7 mo for 9-mo total). LFT at baseline then symptom-driven (monthly if hepatic risk / HBV / HCV / HIV / alcohol / pregnancy) — hold INH/RIF/PZA if ALT >3× ULN symptomatic or >5× ULN asymptomatic. Snellen + Ishihara monthly on ETB. Pyridoxine adherence each visit. ART + IRIS surveillance first 3 mo of ART. Monthly weight for re-dosing. DOT adherence each encounter (ATS/CDC/IDSA 2016 Nahid)
    actions: panel.lft, panel.cbc
    advance: Culture conversion + regimen tolerated
12. 12FOLLOWUP
    End-of-treatment cure assessment per WHO/ATS (culture-negative at end of therapy; treatment-completed if doses verified). Close-contact investigation → IGRA / TST + symptom screen + LTBI evaluation/treatment (CDC LTBI 2020 Sterling — 3HP preferred). Mandatory public-health reporting and case closure. Adherence + relapse education; relapse usually within 6–12 mo (highest if cavitary + month-2 culture+). Long-term follow-up for late toxicity and post-TB lung function (Nahid 2016 PMID 27516382; CDC LTBI 2020)
    advance: Cure / completion documented + contact tracing + reporting complete