Bacteriology - Tuberculosis Flashcards
Decide whether each of the f ollowing statements is more closely associated with 1° or 2° TB:
Radiographic finding = Ghon complex; classically affects lower lobes
1°TB
Decide whether each of the f ollowing statements is more closely associated with 1° or 2° TB:
Miliary TB
2°TB
Decide whether each of the f ollowing statements is more closely associated with 1° or 2° TB:
Fibrocaseous cavitary lung lesion; classically affects apical lungs (↑ affinity for ↑ O2 environment)
2°TB
Decide whether each of the f ollowing statements is more closely associated with 1° or 2° TB:
Symptoms of cough/hemoptysis, fever, night sweats, and weight loss
2°TB
What type of hypersensitivity reaction is seen after infection with M. tuberculosis?
Type IV or delayed-type hypersensitivity (basis for PPD test)
What unique type of cell is seen in association with caseating granulomas in TB?
Langerhans giant cell
What is the mode of transmission of M. tuberculosis!
Respiratory droplets
What term describes the lymphatic and hematogenous spread of TB, causing numerous small foci of infection in extrapulmonary sites?
Miliary TB
Name five common sites of extrapulmonary TB:
- CNS (tuberculous meningitis)
- Vertebral bodies (Pott disease)
- Psoas major muscle → abscess
- GI tract (liver and cecum)
- Cervical lymph nodes →scrofuloderma
What is an effective screening tool for latent TB?
PPD test
How is active TB infection diagnosed?
Clinical and radiologic signs of 2° TB and acid-fast bacilli in sputum
What is the management of PPD + latent TB?
Treatment with INH + pyridoxine (vitamin B6) for 9 months
What is the treatment for active TB?
Respiratory isolation and initial four-drug therapy (RIPE: Rifampin, INH, Pyrizinamide, Ethambutol)
What is the major toxicity of most TB drugs?
Hepatotoxicity; INH → vitamin B 6deficiency; ethambutol → optic neuritis
Decide whether each of the f ollowing statements is more closely associated with 1° or 2° TB:
Radiographic finding = Ghon complex; classically affects lower lobes
1°TB
