Tuberculosis disease and latent tuberculosis infection

Tuberculosis

1. TB Disease and Latent TB
Infection
Karen GalanowskyRN, MPH
Nurse Consultant, TB Program
New Jersey Department of Health &
Senior Services

2. Transmission of M. tuberculosis
•Spread by droplet nuclei
•Expelled when person with infectious TB coughs,
sneezes, speaks, or sings
•Close contacts at highest risk of becoming
infected
•Transmission occurs from person with infectious
TB disease (not latent TB infection)

4. 4
Latent TB Infection (LTBI)
•LTBI is the presence of M. tuberculosis
organisms (tubercle bacilli) without
symptoms or radiographic evidence of TB
disease
•With LTBI, the person is healthy and cannot
spread TB to anyone

5. 5
Testing for M. tuberculosisInfection
•Mantoux tuberculin skin test (TST)
–Skin test that produces delayed-type hypersensitivity
reaction in persons with M. tuberculosisinfection
–Use a cut point of 5mm or 10 mm depending upon the
reason for testing
•QuantiFERON
®
-TB Gold Test
–Blood test that measures and compares amount of
interferon-gamma (IFN-) released by blood cells in
response to TB antigens

6. 6
Persons at Risk for Developing
TB Disease
•Those who have been recently infected
•Those with clinical conditions that increase their risk of
progressing from LTBI to TB disease
–HIV
–Uncontrolled diabetes
–Cancer of the head or neck
–TNF-alpha blockers
Persons at high risk for developing TB disease fall into
2 categories

7. 7
Targeted Tuberculin Testing
•Detects persons with LTBI who would benefit from
treatment
•De-emphasizes testing of groups that are not at high risk for
TB
•Can help reduce the waste of resources and prevent
inappropriate treatment

8. When TB Disease Develops
Symptoms
•Prolonged cough
•Night sweats
•Loss of appetite
•Weight loss
•Fatigue
•Fever
•Chills
•Coughing up blood
•Chest pain

9. Evaluation for TB
•Medical history
•Physical examination
•Mantoux tuberculin skin test or Quantiferon-TB Gold
•Chest radiograph
•Bacteriology testing for smear and culture identification

10. Common Sites of TB Disease
•Lungs
•Pleura
•Central nervous system
•Lymphatic system
•Genitourinary systems
•Bones and joints
•Disseminated (miliary TB)

11. Principles of Treatment for TB Disease
•Treatment for TB disease is usually 6 –9 months
•The four first-line drugs should be used initially until drug
susceptibility studies are determined.
•Dosages should be calculated based on weight (mg/kg)
•All TB medications should be ingested together the
approximately at the same time daily
•TB medications may be given intermittently (twice or thrice
weekly by directly observed therapy after the initial phase of
treatment.

12. MDR and XDR-TB
•MDR-TB -Mycobacterium TB that is resistant to at least
Isoniazidand Rifampin
•XDR TB is defined as resistance to the four first-line drugs, an
injectable, and one of the quinolones
•Individuals with XDR TB are more likely to die during
treatment or have treatment failure
•XDR TB has emerged worldwide as a threat to public health
and TB control raising concerns for a future epidemic of
virtually untreatable TB
•Second-line anti-TB medications are used in the treatment of
MDR and XDR-TB. These are costly, difficult to administer, and
cause serious side effects

13. Factors that Affect TB Transmission
•Infectiousness of person with TB
•Environment in which exposure occurred
•Duration of exposure
•Proximity to the infectious person