Download Pulmonary Board Review Tuberculosis

Pulmonary Board Review
Tuberculosis
Curtis M. Grenoble, MHS, PA-C
Lock Haven University PA Program
Fall 2008
Historical Perspective
• During the 1800’s 1 in 5 persons in the US
had active TB!
• “captain of all men of death” – leading killer
• 1985 there were 9.3 cases per 100,000
• Resurgence in early 1990’s – HIV, and public
policy as well in the late 80’s
• Now 7.4 cases per 100,000
Reported TB Cases*
United States, 1982–2007
28,000
No. of Cases
26,000
24,000
22,000
20,000
18,000
16,000
14,000
12,000
10,000
1983
1986
1989
1992
1995
Year
*Updated as of April 23, 2008.
1998
2001
2004
2007
No. of Cases
Number of TB Cases in
U.S.-born vs. Foreign-born Persons
United States, 1993–2007*
20000
15000
10000
5000
0
1993 1995 1997 1999 2001 2003 2005 2007
U.S.-born
*Updated as of April 23, 2008.
Foreign-born
Transmission of Tuberculosis
Causative organism: Mycobacterium tuberculosis
Aerosolized droplets containing MTB
Persons at Risk
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HIV
Homeless
Live or work in crowded conditions
Immigrants
IVDA
Prison
Immunosuppresion for any reason
DM
Debilitation – ETOH
HCW
Purpose of Targeted Testing
• Find persons with TB disease / LTBI that would
benefit from treatment
• Groups that are not high risk should not be tested
DECISION TO TEST IS A DECISION TO TREAT!
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High Risk Groups:
Close contacts of a person known or suspected to have TB
Foreign-born persons of high incidence countries
Residents and employees of high-risk congregate settings
Health care workers (HCW) serving high-risk clients
Medically underserved, low income populations
Children exposed to adults in high-risk categories
Persons who inject illicit drugs
Persons with HIV / certain medical conditions
How is the skin test read?
• Test is read by a trained health worker 48 - 72 hours
after the tuberculin injection
• Diameter of the indurated area is measured
transversely across the forearm
• Erythema (redness) is not measured
• Test result is measured in millimeters (mm)
– ≥ 5mm: HIV+, recent TB exposure, x-ray evidence,
immunosuppressed
– ≥ 10mm: recent immigrants from high risk country, illicit drug
users, HCW, correctional facilities, LTC facilities, DM CRF
– ≥ 15mm: Persons with no known risk, HCW otherwise at low
risk and received baseline testing at start of employment
False Positive PPD Skin Tests
• Error in administering the test
• Cross-reaction with nontuberculous
mycobacterial antigens
• Any previous bacille Calmette-Guérin
vaccination
Delayed Positive Reaction
• Booster phenomenon
Latent Tuberculosis Infection
LTBI
Person:
• Not acutely ill
• Not contagious
Germs:
• “Sleeping” but still alive
• Surrounded (walled off ) by body’s
immune system
In LTBI
• TB germs are “sleeping” and body defenses
are keeping them from growing
• The TB skin test is usually positive
• Chest x-ray = normal
• Sputum culture = negative
Isoniazid Regimens
• INH daily for 9 months
(270 doses within 12 months)
• INH twice/week for 9 months
(76 doses within 12 months)
• INH daily for 6 months
(180 doses within 9 months)
• INH twice/week for 6 months
(52 doses within 9 months)
Isoniazid Regimens
• 9-month regimen of INH - Preferred
• 6-month regimen - less effective but is an
alternative
• Daily vs. intermittent (twice weekly)
– Use directly observed therapy (DOT) for
intermittent regimen
• Completion of Therapy
–Determined by total number of doses administered
–Not on duration alone.
Alternative Regimens:
Rifampin
• Rifampin (RIF) - daily for 4 months is an
acceptable alternative when treatment
with INH is not feasible.
– Side effect
• Rifabutin - alternative to Rifampin
(e.g. - HIV-infected persons receiving
protease inhibitors)
Hepatitis Risk in LTBI Treatment
• Incidence of hepatitis in persons taking
INH is lower than previously thought (0.1
to 0.15%)
• Hepatitis risk increases with age
– Uncommon in persons < 20 years old
– Nearly 2% in persons 50 to 64 years old
• Risk increased with underlying liver disease
or heavy alcohol consumption
Laboratory Monitoring INH Patients
• Baseline LFT’s
• HCG, HIV, Hepatitis Panel, Etoh
• Obtain repeat LFT’s during treatment only if
patient becomes symptomatic, or if high risk for
toxicity
• Discontinue INH if transaminase levels are
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3 times the upper limit of normal if symptoms of
hepatotoxicity (rash, anorexia, N/V, RUQ pain,
fatigue, weakness, dark urine, numb hands/feet)
5 times the upper limit of normal if patient is
asymptomatic
What causes TB infection to become
TB disease?
Wall breaks down
due to a weakened immune system
~10% of those infected with develop disease over their lifetime
TB disease
Germs:
• Awake and multiply
• Cause damage
Person:
• May feel sick
• May be contagious
Symptoms of TB
• Cough
– Productive, lots of sputum
– Persistent 3 weeks or longer
– Coughing up blood or bloody sputum
– Does not respond to other antibiotics
Symptoms of TB
• Fatigue
• Weight loss (unexplained)
• Loss of appetite
• Night Sweats
• Chest pain
• (Constitutional symptoms)
TB Disease in the Body
Brain
Eye
Lymph node
Throat
Lung * (Most Common)
Bone
Spine
Kidney
Up to 40% of TB in children involves extrapulmonary sites (bones, LN, kidneys)
Sputum Collection
Sputum specimens essential to confirm TB
• Sputum: mucus from within the lung, not saliva
• 3 specimens on 3 different days
• Spontaneous morning sputum
• Positive (Acid-fast bacilli)
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Need at least 10,000 bacilli per ml
Positive in about half those with TB disease
Signal a very infectious person
Others (mycobacterium avium) may produce “false positive”
– Sputum culture (“Gold standard”)
General Principles of TB Treatment
• Always treat with multiple drugs
• Never add a single drug to a failing regimen
• Treatment course depends on drugs selected
• Non-adherence
• The single most important reason for tuberculosis
treatment failure
Anti TB Medications
First-Line
Second-Line
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Isoniazide
INH
Rifampin
RIF
Ethambutal EMB
Rifabutin
Pyrazinamide PZA
Streptomycin
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Capreomycin
Kanamycin
Amikacin
Ethionamide
Para-aminosalicyclic
Cycloserine
Cipro
Levofloxacin
Resources for Health Care Providers
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Centers for Disease Control and Prevention
1600 Clifton Rd.
Atlanta, GA 30333
Telephone: 800-311-3435; 404-639-3311
Web site: http://www.cdc.gov
National Jewish Medical and Research Center
1400 Jackson St.
Denver, CO 80206
Telephone: 303-388-4461
Physician Consult Line (Monday - Friday, 8 a.m. to 5 p.m. MT): 800-652-9555
Web site: http://www.njc.org
American Thoracic Society
1740 Broadway
New York, NY 10019
Telephone: 212-315-8700
Fax: 212-315-6498
Web site: http://www.thoracic.org