Mycobacterial Infections

Question 1

What are the rapid growing mycobacteria?

Answer 1

M fortuitum
M chelonae
M absessus

Question 2

What are the slow growing mycobacteria?

Answer 2

M kansaii
M marinum
M avium complex
-M Avium
-M intracellulare

Question 3

What is a common sourse of Non-TB pulm infections?

Answer 3

Water sources
inhalation of aerosols from natural water source or from a heating system

MAC, M kansii, M absessus

Question 4

In what population does progressive lung disease occur

Answer 4

Pts with underlying bronchiectaisis or COPD

Question 5

What are the 2 clinically seen forms of MAC?

Answer 5

.

Question 6

What is the typical imaging finding in Non-TB Myco Infections

Answer 6

Interstitial infiltrates with rare cavitation and involvement of >3 lobes

Question 7

How is Non-TB Myco Infection confirmed?

Answer 7

Clinical H and P
Bacterologic confirmation
-2 pos cultures
BAL sample
Lung or tissue biopsy positive AFB smears
Pos culture from pleural fluid or non pulm site

Question 8

What Abtx are used for Mycobacterium infections

Answer 8

Clarithromycin OR azithromycin
AND Rifampin 
AND Ethambutol
12-18 mon
Macrolides

Question 9

What is the cause of Pott’s Disease?

Answer 9

Bone infiltration with Mycobactrium

Question 10

What part of the world is TB most common?

Answer 10

Sub saharan africa
India
Southeast Asia
Indonesia

Question 11

What are the 3 possible consequences of inhalation of droplet nuclei?

Answer 11

Organism cleared 70%

Primary TB with active disease 5%
Latent infection with possibility of reactivation. 5%

Very small number have late progression as a result of latent TB

Question 12

What is the finding in initial infection that is not conrolled by local defenses?

Answer 12

Ghon Complex seen on X-ray: Unilateral lymphadenopathy

Hematogenous dissemination if CMI not adequate. Active disease and contageous

Question 13

What are the S and S of Primary TB?

Answer 13

Fever and pulmonary symptoms
chest pain
hilar adenopathy, perihilar infiltrates, effusion

Question 14

How is latent TB diagnosed?

Answer 14

Evidence of a cell mediated immune response.
Positive TB skin test
Interferon Gamma release assay (Quantiferon Gold)

Question 15

How is the Tuberculin Skin test read?

Answer 15

mm of induration

NOT erythema perpendicular to the long axis of the forearm

Question 16

Under what circumstance would a TB skin test be negative when they ARE infected?

Answer 16

Immunosupressed
Cancer Tx
Alcoholism
Anything that would supress the Cell mediated immunity

Question 17

What diagnostic test for TB would you use if you know someone has recieved the BCG vaccine?

Answer 17

Quanterferon Gold

Question 18

What is the LBTI Treatment for TB?

Answer 18

Isoniazid 300mg daily for 9mon

Question 19

What are the risk factors for Tuberculosis?

Answer 19

Silicosis
Diabetes 
Chronic Renal Failure 
Gastrectomy, jejunoileal bypass
Weight Loss >10% ideal body wt
Children

Question 20

What are the symptoms of TB?

Answer 20

Diurnal Fever becoming more marked as disease progresses
Fever and NS
Grad Cough Prog. with devt of sputum production
Gross Hemoptysis
Dyspnia
Pleuritic Pain
Anorexia, wasting(consumption

Question 21

What are general principles of TB Tx?

Answer 21

Always use at least 2 drugs
Appropriate drug doses
Take drug regularly
Adequate duration of therapy

Question 22

What is included in the 4 drug treatment for TB?

Answer 22

INH, ethambutol, rifampin, pyrazinamide
Daily for 8wks OR
Daily 2wks then 2x week 
3x week for 6wks
DOT recommended for schedules that dont require daily dosing

Question 23

What defines Drug resistant TB?

Answer 23

Lab confirmed resistance to INH and RIF

Question 24

What is used to DIAGNOSE TB?

Answer 24

Positive Sputum Culture