What is the appropriate management for a patient suspected of having tuberculosis (TB)?

Management of Suspected Tuberculosis (Koch's Disease)

Patients suspected of having tuberculosis require immediate isolation in a single room (preferably negative pressure ventilation), prompt initiation of four-drug therapy (isoniazid, rifampin, pyrazinamide, and ethambutol) for 2 months followed by isoniazid and rifampin for 4 months, and sputum collection for acid-fast bacilli smear and culture before treatment begins. 1, 2, 3

Immediate Infection Control Measures

Isolation and respiratory precautions must begin immediately upon suspicion, not after confirmation. 1

• Place the patient in a single room with negative pressure ventilation if available, or transfer to a facility with such capabilities if not locally available 1
• Healthcare workers must wear respiratory protection (N95 or equivalent particulate respirators) when entering the patient's room or performing any procedures 1
• The patient should wear a surgical mask when outside the isolation room and be instructed to cover mouth and nose when coughing or sneezing 1
• Separate suspected TB patients from immunocompromised patients (including HIV-positive individuals) in different wards or clinics entirely 1

Diagnostic Evaluation Before Treatment

Obtain sputum specimens for acid-fast bacilli (AFB) smear and culture immediately, but do not delay treatment while awaiting results. 1, 2

• Collect at least three sputum samples for AFB smear and mycobacterial culture before initiating therapy 1
• Perform chest radiography to assess for pulmonary involvement, cavitation (indicates higher infectiousness), and extent of disease 1, 4
• Drug susceptibility testing must be performed on all initial isolates to guide continuation therapy 2, 4
• Assess for HIV co-infection as this fundamentally alters management and prognosis 1, 5

Standard Treatment Regimen for Drug-Susceptible TB

The intensive phase consists of four drugs daily for 2 months: isoniazid, rifampin, pyrazinamide, and ethambutol. 2, 3, 4

Intensive Phase (First 2 Months)

• Isoniazid, rifampin, pyrazinamide, and ethambutol administered daily as the standard regimen 2, 3, 4
• Daily dosing is strongly preferred over intermittent therapy to prevent resistance emergence 6
• Use fixed-dose combinations to improve adherence and prevent inadvertent monotherapy 6
• Ethambutol can be discontinued once susceptibility testing confirms no resistance to isoniazid and rifampin 2, 4

Continuation Phase (Months 3-6)

• Isoniazid and rifampin daily for at least 4 additional months (total 6 months minimum) 2, 4
• Extend treatment duration if: patient remains sputum/culture positive, resistant organisms are present, or patient is HIV-positive 2

Monitoring During Treatment

Weekly monitoring is essential during the first month to detect hepatotoxicity and treatment response. 6, 7

• Baseline liver function tests (AST, ALT, bilirubin) before starting therapy 6, 7
• Monitor liver enzymes weekly for 2 weeks, then every 2 weeks during the intensive phase 6, 7
• Stop rifampin, isoniazid, and pyrazinamide immediately if AST/ALT rises to >5× normal or bilirubin increases 6, 7
• Repeat sputum smears and cultures to monitor treatment response until smears become negative 1, 2

Drug Reintroduction After Hepatotoxicity

If hepatotoxicity occurs, reintroduce drugs sequentially once liver function normalizes: isoniazid first, then rifampin, finally pyrazinamide. 6, 7

• Use streptomycin and ethambutol temporarily until liver function normalizes 7
• If pyrazinamide is the offending drug, continue rifampin and isoniazid for 9 months total with ethambutol for initial 2 months 6
• Never use fixed-dose combinations during reintroduction as you must identify the specific offending agent 6

Determining When Patient is Non-Infectious

Patients may discontinue isolation when they meet specific clinical and microbiological criteria, with each case requiring specialist physician involvement. 1

Key factors indicating reduced infectiousness include: 1

• Clinical improvement with resolution of cough and fever
• Three consecutive negative AFB sputum smears collected on different days
• At least 2 weeks of appropriate anti-TB therapy with documented adherence
• Absence of cavitation on chest radiograph (cavitary disease indicates higher infectiousness)

Special Circumstances

Multidrug-Resistant TB (MDR-TB)

All suspected or confirmed MDR-TB patients require negative pressure room isolation and transfer to specialized facilities if not locally available. 1

• Staff and visitors must wear enhanced respiratory protection (PFR 95 or equivalent) during all patient contact 1
• Maintain isolation until cultures are negative, not just smears 1
• All treatment must be fully supervised (directly observed therapy) unless exceptional circumstances exist 1

Cough-Inducing Procedures

Bronchoscopy, sputum induction, and aerosol treatments should only be performed in appropriately ventilated areas with healthcare workers wearing respiratory protection. 1

• Avoid cough-inducing procedures unless absolutely necessary 1
• Perform in negative pressure rooms or booths with local exhaust ventilation 1

Critical Pitfalls to Avoid

• Never delay TB treatment to optimize other conditions – tuberculosis is immediately life-threatening and infectious 6
• Never add a single drug to a failing regimen – this promotes drug resistance 6
• Never discontinue pyrazinamide for asymptomatic hyperuricemia alone – this is expected and clinically insignificant 6
• Never assume a patient is non-infectious based on symptom improvement alone – microbiological confirmation is required 1
• Never allow suspected TB patients to remain in waiting areas with immunocompromised patients 1

Adherence Strategy

Directly observed therapy (DOT) is essential for at least the intensive phase and should be considered for the entire treatment course. 6, 7

• Video-observed treatment is an acceptable alternative to in-person DOT 6
• Secure arrangements for supervised therapy must be established before hospital discharge 1
• Each dose should be dispensed by trained staff who watch the patient swallow medications and monitor for adverse effects 1