Tuberculosis (TB) Disease Management

Clinical assessment

Suspect based on symptoms (chronic cough, fever, night sweats, weight loss) and risk factors. Requires differentiation from other respiratory/systemic illnesses (Pneumonia, COVID-19, HIV/AIDS complications, malignancy, COPD, fungal infections). Clinical staging definitions important: Presumptive TB (symptoms/CXR suggestive); Bacteriologically confirmed TB (positive smear/Xpert/culture); Clinically diagnosed TB (clinician diagnosis based on signs/symptoms/investigations without bacteriological proof). Classification based on Site (Pulmonary/Extrapulmonary), History (New, Relapse, Failure, Loss to follow-up, Unknown), Drug Susceptibility (DS-TB, DR-TB [RR, Mono, Poly, MDR, XDR]), HIV status.

Differential diagnosis

• Histoplasma pneumonia, trypanosomiasis, brucellosis
• Pneumonia
• COVID-19
• HIV/AIDS complications
• Malignancy
• COPD, asthma, bronchiectasis, emphysema
• Post TB lung disease
• Fungal infection of the lungs e.g. Aspergillosis

Investigations

• Sputum/Other Sample Testing: GeneXpert MTB/RIF (Recommended primary diagnostic test for all presumptive TB; detects TB and Rifampicin resistance), Sputum Smear Microscopy for AFB (ZN stain - use if Xpert unavailable, but send sample for Xpert), TrueNat, TB LAMP (Alternative molecular tests).
• Culture and Drug Susceptibility Testing (DST): Confirmatory test, provides full resistance pattern. Indicated for Rifampicin resistance on Xpert, treatment failure suspects, patients remaining positive at month 2 despite Rif-sensitivity.
• Chest X-ray (CXR): Supports diagnosis (esp. in smear/Xpert negative PTB or EPTB), can show cavities, infiltrates, effusion. Not sufficient alone for diagnosis usually.
• Other imaging: Abdominal Ultrasound (for abdominal TB), CT/MRI (for CNS/bone TB).
• Biopsy: Lymph node, pleura, other tissues for histology and Xpert/culture.
• Tuberculin Skin Test (TST) / Interferon-Gamma Release Assay (IGRA): Supportive for diagnosing LTBI, limited role in diagnosing active disease (especially in high-burden/BCG vaccinated settings). TST can support pediatric diagnosis.
• HIV Testing: Offer to ALL presumed and diagnosed TB patients.

Diagnostic criteria

Diagnosis based on bacteriological confirmation (Xpert, smear, culture) OR clinical diagnosis (symptoms, signs, supportive investigations like CXR, histology) by a clinician following national guidelines.

Non-pharmacological management

• Directly Observed Treatment (DOT): Ensuring patient takes medication under observation by a treatment supporter (health worker, community volunteer, family member).
• Digital Adherence Technologies (DAT): Emerging tools to support adherence.
• Patient-Centered Care Approach.
• Nutritional Support: Assessment and counseling.
• Infection Control: Educate on cough hygiene (covering mouth, sputum disposal), promote ventilation.
• Contact Tracing: Identify and screen close contacts (household, workplace) for active TB and eligibility for TPT.
• Psychosocial Support.
• Pulmonary Rehabilitation (for post-TB lung disease).

Pharmacological treatment

• Standard 1st Line Regimen (Drug-Susceptible TB, Rifampicin-Sensitive on Xpert, All patient categories including new/retreatment unless DR-TB confirmed):
• - Intensive Phase (2 months): Rifampicin (R) + Isoniazid (H) + Pyrazinamide (Z) + Ethambutol (E). [2RHZE]
• - Continuation Phase (4 months): Rifampicin (R) + Isoniazid (H). [4RH]
• - Total Duration: 6 months.
• Special Cases (DS-TB):
• - TB Meningitis / Osteoarticular (Bone/Joint) TB: Intensive Phase: 2RHZE. Continuation Phase: 10RH (Total 12 months).
• Alternative 1st Line Regimens (Specific situations):
• - Children (2mo-16yrs, non-severe): 2 HRE(Z) / 2RH (4 months total).
• - Adults (>12yrs, >40kg, HIV+ with CD4>100): 2 HPMZ / 2HPM (4 months total) [H=INH, P=Rifapentine, M=Moxifloxacin, Z=Pyrazinamide].
• Drug-Resistant TB (DR-TB):
• - Rifampicin-Resistant (RR-TB) / Multidrug-Resistant (MDR-TB): Requires treatment with specific second-line drug regimens based on DST results. Refer to designated DR-TB treatment facility/specialist.
• - INH Mono-resistance: 6(H)REZ–Levofloxacin (Requires specialist consultation/confirmation).
• Adjunctive Therapy:
• - Pyridoxine (Vitamin B6) 25 mg daily: Give with INH-containing regimens to prevent peripheral neuropathy.
• - Prednisolone 1-2 mg/kg/day (max 60mg) for 4 weeks, then taper over 2 weeks: For severe inflammation (TB meningitis, sometimes pericarditis/extensive disease).
• Management of Side Effects: Minor (e.g., orange urine - reassure; nausea - take meds with food; mild joint pain - analgesia). Moderate/Severe (Rash - antihistamines, consider stopping drug; Neuropathy - increase Pyridoxine, stop INH if severe; Hepatitis/Jaundice - STOP all drugs, refer; Visual impairment - STOP Ethambutol; Hearing loss - STOP Streptomycin [if used]). Follow specific guidelines for managing severe reactions/reintroduction.
• HIV Co-infection: Start ART within 2 weeks of starting TB treatment (see HIV001 and UCG Section 3.1.10.1 for regimen adjustments due to Rifampicin interactions).

Monitoring

• Clinical: Regular assessment (monthly) for symptom improvement, weight gain, adherence, side effects.
• Bacteriological (PTB): Sputum smear/Xpert at end of intensive phase (Month 2), Month 5, and end of treatment (Month 6 for standard regimen). Smear positive at month 2 requires Xpert for RR check; if sensitive, continue treatment, address adherence, repeat smear at month 3. Smear/Xpert positive at month 5 or later indicates Treatment Failure -> Perform Culture/DST, refer for DR-TB management.
• Radiological (CXR): Baseline useful, but not reliable for routine monitoring of treatment response (changes lag).
• Treatment Outcomes: Assign outcome at end of treatment (Cure, Treatment Completed, Treatment Failure, Died, Lost to Follow-up, Not Evaluated). Treatment Success = Cure + Treatment Completed.