What is the recommended protocol for hospital testing and treatment of tuberculosis?

Hospital Testing and Treatment Protocol for Tuberculosis

The recommended protocol for hospital testing of tuberculosis includes obtaining three sputum specimens for microscopy, culture, and drug susceptibility testing, followed by a standard treatment regimen of isoniazid, rifampin, pyrazinamide, and ethambutol for 2 months, then isoniazid and rifampin for 4 additional months for drug-susceptible tuberculosis. 1

Diagnostic Testing Protocol

Initial Specimen Collection

• Obtain three sputum specimens, preferably early morning samples on separate days 1
• Collection should be performed in an airborne infection isolation (AII) room or sputum induction booth to prevent transmission 1
• For patients unable to produce sputum, consider sputum induction with hypertonic saline or bronchoscopy under appropriate infection control measures 1
• For children under 10 years who cannot produce sputum, early morning gastric aspirates may be collected (expected yield ~50%) 1

Laboratory Testing Requirements

• Acid-fast bacilli (AFB) microscopy should be completed within 24 hours of specimen collection 1
• Nucleic acid amplification (NAA) testing should be completed within 48 hours to rapidly identify M. tuberculosis complex 1
• Mycobacterial culture should be performed using both solid and liquid media systems, with results available within 14 days 1
• Identification of cultured mycobacteria should be completed within 21 days 1
• Drug susceptibility testing for first-line drugs should be performed on initial isolates and completed within 30 days 1

Additional Diagnostic Tests

• Chest radiography is essential for all patients with suspected TB 1
• HIV testing should be performed for all patients with TB or suspected TB 1
• Baseline laboratory tests should include serum aminotransferases, bilirubin, alkaline phosphatase, serum creatinine, and platelet count 1
• Visual acuity and red-green color discrimination testing should be performed when ethambutol is to be used 1

Treatment Protocol

Initial Treatment Phase (First 2 Months)

• For drug-susceptible TB, administer a four-drug regimen consisting of: 1
  • Isoniazid: 5 mg/kg (maximum 300 mg) daily 2
  • Rifampin: 10 mg/kg (maximum 600 mg) daily 1
  • Pyrazinamide: 15-30 mg/kg (maximum 2 g) daily 3
  • Ethambutol: 15 mg/kg daily 4

Continuation Phase (Next 4 Months)

• After 2 months, if susceptibility to isoniazid and rifampin is confirmed and clinical improvement is observed, continue with: 1
  • Isoniazid: 5 mg/kg (maximum 300 mg) daily 2
  • Rifampin: 10 mg/kg (maximum 600 mg) daily 1

Special Considerations

• Treatment should be extended to 9 months if 2-month culture remains positive 1
• For TB meningitis, treatment should be extended to 12 months 5
• For spinal TB with neurological involvement, treatment should continue for 9 months 5
• For HIV co-infected patients, appropriate adjustments with antiretroviral therapy should be made 3
• Second-line drug susceptibility testing should be performed for patients with prior TB treatment, contacts of drug-resistant TB patients, or those with persistent positive cultures after 3 months of treatment 1

Monitoring During Treatment

Bacteriologic Monitoring

• Collect sputum specimens monthly until two consecutive specimens are culture-negative 1
• More frequent AFB smears may be useful to assess early treatment response and infectiousness 1

Clinical Monitoring

• Perform monthly clinical evaluations to identify possible adverse effects and assess adherence 1
• For patients on ethambutol, monthly testing of visual acuity and color discrimination should be performed 1
• Routine measurements of hepatic and renal function are not necessary unless patients have baseline abnormalities or increased risk of hepatotoxicity 1

Infection Control

• Maintain respiratory isolation for patients with suspected or confirmed pulmonary TB until they are determined to be non-infectious 1
• A patient is considered non-infectious when receiving effective therapy, showing clinical improvement, and having three consecutive negative sputum AFB smears collected on different days 1
• Respiratory isolation can be discontinued after 3 weeks of effective therapy or when three negative smears are obtained 5

Common Pitfalls and Caveats

• Failure to obtain adequate specimens before starting treatment can lead to inability to confirm diagnosis and determine drug susceptibility 1
• Relying solely on smear microscopy is insufficient as it has limited sensitivity (only 63% of culture-positive cases have positive smears) 1
• Delaying treatment while awaiting culture results in highly suspicious cases can lead to disease progression and continued transmission 1
• Not testing for HIV in TB patients misses an important comorbidity that affects treatment decisions 1
• Inadequate monitoring during treatment may fail to detect adverse drug reactions or treatment failure 1
• Premature discontinuation of respiratory isolation can lead to nosocomial transmission 1