Micro Tuberculosis

Question 1

Primary tuberculosis

Answer 1

initial case of tuberculosis

Question 2

Secondary Tuberculosis

Answer 2

reactivated tuberculosis

Question 3

Disseminated tuberculosis

Answer 3

tuberculosis involving multiple systems (miliary TB)

Question 4

Aerobic
Acid fast rods (mycolic acid)
grows slowly
facultative intracellular

Answer 4

Mycobacterium tuberculosis
Transmission: inhalation
Virulence: cord factor
Tissue necrosis is due to immune response

Question 5

Mild fever, Sweating
Chest pain
Cough (productive, sputum may be bloody)
fatigue, Malaise
Weight loss

Answer 5

Tuberculosis

Question 6

RF for Tuberculosis

Answer 6

Poor nutrition, drug users, alcoholics, crowded living conditions, immunocompromised,

endemic areas: SE Asia, sub-saharan African, Easter Europe

Question 7

TB progression

Answer 7

Inhalation of bacteria, Engulfed by alveolar macrophages

Survive & multiply; Attract and activate more macrophages

Formation of tubercle/granulomas
dormant for yrs/decades (Immunosuppressed)

Question 8

Tubercles changes over time

Answer 8

Caseous lesion
Ghon complexes
Tuberculous cavities

Question 9

Testing for TB

Answer 9

PPD test/Mantoux/Tuberculin skin test: positive means exposure
CXR: tubercles
Sputum: Acid fast & fluorescent auramine stain
Lowenstein-Jensen agar

Question 10

TB treatment

Answer 10

Combination therapy
Treatment consists of 4 drugs: Isoniazid, Rifampin, Ethambutol and Pyrazinamide.
Initial phase: usually 2 months followed by 4 months of continuation phase.

isoniazid if potential exposure

Question 11

MDR-TB: multidrug resistant

Answer 11

resistant to isoniazid and rifampin

Question 12

XDR-TB: extremely drug resistant

Answer 12

resistant to isoniazid, rifampin, and fluoroquinolones, as well as either aminoglycosides (Amikacine, kanamycine) or capreomycin. at least one of the 2nd line drugs

Question 13

BCG Vaccine

Answer 13

Live, attenuated M. Bovis

Question 14

Weakly gram pos
acid-fast aerobic rods
mycolic acid in cell wall
slow growing in culture
normal inhabitants of soil and water

Answer 14

Mycobacterium avium complex
MAC pneumonia
inhalation
primary: similar to TB
secondary: in all organs and blood stream, AIDS pts with low CD4+ T cell counts, <50 cells/ml

Question 15

Immunocompromised

Chronic pulmonary disease

Answer 15

MAC pneumonia RF

Question 16

Diagnose MAC Pneumonia

Answer 16

acid fast stain

Question 17

Treatment MAC Penumonia

Answer 17

Clarithromycin or Azithromycin combines with Ethambutol and Rifampin
if you have AIDS give Clarithromycin and Azithromycin

Question 18

Immunocompromised

Renal transplant

Answer 18

Norcardiosis RF

Question 19

Gram positive, aerobic
Weakly acid fast staining
branching filaments
Normal found in soil

Answer 19

Nocardia

transmission: inhalation

Question 20

Fever
Night sweats
Malaise
Chest/abdominal pain
Persistent cough
Anorexia

Answer 20

Nocardiosis

pulmonary infection, lung abscesses
spread and form abscesses in brain or kidney

Question 21

Diagnostics for Nocardiosis

Answer 21

microscopy of sputum: branched long rods

culture: blood or chocolate agar

Question 22

Nocardiosis treatment

Answer 22

IV trimethoprimsulfamethoxazole

Linezolid