Tuberculosis Flashcards
Tuberculosis (TB): Resistance
- 4 million people infected and 1.67 million deaths worldwide in 2016 attributed to TB
- One-third of the world population is infected
Resistance is a growing problem
- Acquired resistance to TB medications stems from inadequately or inappropriately prescribed treatment regimens or from patient noncompliance
- Multidrug-resistant TB is becoming a growing problem
Tuberculosis: Pathophysiology
- Infectious disease caused by M. Tuberculosis
- Inhaled into the alveolus and spreads from lungs
- M. tuberculosis grows slowly
- Infection spread almost exclusively by aerosolization of contaminated lung secretions
Tuberculosis: Goals of Treatment
Accurate diagnosis
- Screening via purified protein derivative (PPD) or QuantiFERON-TB serum test
- Chest x-rat, if indicated
Completion of the recommended therapy
Effective treatment to treat patient and prevent transmission
Tuberculosis: Rational Drug Selection
- Risk stratification
- – High risk: children younger than age 4 years, patients with HIV/AIDs, transplant recipients, foreign-born patients
- Drug therapy principles
- Treatment regiments must contain multiple drugs to which the organisms are susceptible
- The drugs must be taken regularly
- Drug therapy must continue for a sufficient period
- Two phases of treatment
- – Initiation phase is for first 2 months
- – Continuation phase lasts 4 months
- Follow guidelines for 6-month regimen
- Drug-resistant TB:
- – Is determined by susceptibility testing
- – Is treated with at least two drugs that TB is sensitive to based on susceptibility testing
- – If a patient is resistant to multiple first-line drugs (isoniazid [INH], rifampin [RIF], ethambutol [EMB], pyrazinamide), then it is treated with at least 3 new drugs that the organism is susceptible to
Tuberculosis: Patient Variables
Pregnancy and Lactation
— Treat with INH, RIF, EMB (4 drugs if HIV positive)
— Pyridoxine 25 mg/day
— Increased risk of INH-induced hepatitis
Pediatric patients
— May use gastric lavage if unable to get sputum
— May progress to miliary TB or CNS disease
— Treatment with INH and RIF
— Pyridoxine 25 mg/day
HIV-positive
— May not have positive PPD
— Extrapulmonary TB common
— Treatment same as for uninfected adults (four-drug therapy)
Tuberculosis: Monitoring
Sputum cultures monthly until negative
Chest x-ray at completion of therapy to document baseline post- TB chest x-ray
Monitoring for adverse drug reactions
- Baseline liver enzymes, bilirubin, creatinine, CBC, platelet
- Baseline ophthalmology examination if treating with EMB
- Monitoring for hepatitis if on INH monthly
- Monitoring for peripheral neuropathy if on INH
Tuberculosis: Outcome Evaluation
Sputum evaluation monthly
- TB-free after 2 months of treatment
Patient Compliance
Tuberculosis: Patient Education
Extensive education is critical to treatment success
All medication must be taken as scheduled
Repeat education should be provided at each monthly visit
Education should be provided in patient’s primary language
Peer health counselors may be helpful
Tuberculosis Prevention
Positive TB test but no signs of active TB
Drug therapy
- INH alone for 6-9 months
- Need to monitor monthly
- Directly observed therapy may be necessary
- Successful treatment determined by absence of disease
- Patient education critical to successful treatment