TUBERCULOSIS CASE MANAGEMENT AND CONTACT INVESTIGATION INTENSIVE
MARCH 19-22, 2019
TB BASICS
LEARNING OBJECTIVES
Upon completion of this session, participants will be able to:
1. List the four strategies that the Centers for Disease Control and Prevention recommends for
public health agencies to implement in order to control and prevent tuberculosis
2. Identify several characteristics that distinguish active TB disease from latent TB infection
(LTBI)
3. Appropriately apply the American Thoracic Society TB classifications
INDEX OF MATERIALS PAGES
1. TB basics – slide outline Presented by: Ann Raftery, RN, BSN, PHN, MSc
9
SUPPLEMENTAL MATERIAL
1. CDC. Table 2.8: TB Classification System. In: Chapter 2: transmission and pathogenesis of
tuberculosis. Core Curriculum on Tuberculosis: What the Clinician Should Know. Atlanta, GA:
2011:40.
2. Resources on Tuberculosis.
3. Acronyms and Abbreviations.
ADDITIONAL REFERENCES
• ATS/CDC. Diagnostic Standards and Classification of Tuberculosis in Adults and Children. Am J
Respir Crit Care Med. 2000; 161(4):1376-1395. doi: 10.1164/ajrccm.161.4.16141.
• ATS/CDC/IDSA. Controlling Tuberculosis in the United States Recommendations from the
American Thoracic Society, CDC, and the Infectious Diseases Society of America. MMWR. 2005;
54(RR-12):15.
• CDC/NCEZID. CDC immigration requirements: technical instructions for tuberculosis screening and
treatment using cultures and directly observed therapy. October 1, 2009: 1-37.
http://www.cdc.gov/ncidod/dq/panel_2007.htm.
• Gideon HP, Flynn JL. Latent tuberculosis: what the host “sees”? Immunol Res. 2011; 50:202-12.
TB BasicsAnn Raftery, RN, BSN, PHN, MScCurry International Tuberculosis Center
TB Case Management and Contact Investigation IntensiveMarch 19-22, 2019 1
TB BASICS
Ann Raftery, RN, PHN, MScCurry International Tuberculosis Center
Case Management and Contact Investigation Intensive March 2019
Overview
1. Priority strategies for TB prevention and control
2. TB Transmission and Pathogenesis
• Latent TB infection (LTBI)
• Active TB disease
3. Tuberculosis Classifications
2
TB BasicsAnn Raftery, RN, BSN, PHN, MScCurry International Tuberculosis Center
TB Case Management and Contact Investigation IntensiveMarch 19-22, 2019 2
What are the priority strategies in public health
for TB prevention and control?
3
Priority Strategies for TB Prevention & Control
1. Early and accurate detection, diagnosis, and reporting of TB cases leading to initiation and completion of treatment
2. Identification of contacts of patients with infectious TB and treatment of those at risk with an effective drug regimen
3. Identification of other persons with latent TB infection at risk for progression to TB disease and treatment of those persons with an effective drug regimen
4. Identification of settings in which a high risk exists for transmission of Mycobacterium tuberculosis and application of effective infection-control measures
Source: ATS/CDC/IDSA. Controlling Tuberculosis in the United States Recommendations from the American
Thoracic Society, CDC, and the Infectious Diseases Society of America. MMWR 2005; 54 (No. RR-12):15. 4
TB BasicsAnn Raftery, RN, BSN, PHN, MScCurry International Tuberculosis Center
TB Case Management and Contact Investigation IntensiveMarch 19-22, 2019 3
Latent TB infection or active TB disease?
What features distinguish one from the other?
5
TB Transmission and Pathogenesis
Not everyone who is exposed to TB will become infected
Adequate Immunity
No infection (70%)
Infection (30%)
Inadequate Immunity
Non-specific immunity
EXPOSURE
6
TB BasicsAnn Raftery, RN, BSN, PHN, MScCurry International Tuberculosis Center
TB Case Management and Contact Investigation IntensiveMarch 19-22, 2019 4
Risk Factors for TB Infection
The chance of INFECTION Increases when…
• The concentration of TB bacteria circulating in the air is greater
– Coughing; smear-positive; cavitary disease
– Poor ventilation; small enclosed space
• More time is spent with the infectious person (frequency and duration)
• Exposure occurs in an area where the bacteria can easily survive (no UV light)
7
Pathogenesis
Droplet nuclei containing tubercle bacilli are inhaled, enter the lungs, and travel to the alveoli.
Tubercle bacilli multiply in the alveoli.
TB BasicsAnn Raftery, RN, BSN, PHN, MScCurry International Tuberculosis Center
TB Case Management and Contact Investigation IntensiveMarch 19-22, 2019 5
TB Pathogenesis
Immunologic defenses
Inadequate Defenses
Early progression
TB disease (5-10%)
Adequate Defenses
Containment(90-95%)
No infection (70%)
Adequate Immunity
Non-specific immunity
Inadequate Immunity
EXPOSURE
Infection (30%)
9
DISSEMINATION: Spread of TB to Other Parts of the Body
1. Lungs (85% all cases)
2. Pleura
3. Central nervous system
(spine, brain, meninges)
4. Lymph nodes
5. Genitourinary system
6. Bones and joints
7. Disseminated (miliary)
© ITECH, 2006
TB BasicsAnn Raftery, RN, BSN, PHN, MScCurry International Tuberculosis Center
TB Case Management and Contact Investigation IntensiveMarch 19-22, 2019 6
TB Pathogenesis (3)
Immunologic defenses
Inadequate Defenses
Early progression
TB disease (5-10%)
Adequate Defenses
Containment(90-95%)
No infection (70%)
Adequate Immunity
Non-specific immunity
Inadequate Immunity
Infection (30%)
EXPOSURE
Immunologic defenses
Continued
containment
Adequate Defenses
Inadequate Defenses
Late progression TB disease
(5-10%)
11
Risk Factors for Progression of Infection to TB Disease
• 10% of persons with normal immune systems develop TB at some point in their lifetime
• Recent infection (within 1-2 years of infection)
• Conditions/treatment that impairs immune control of M.tb
12Ai J-W, et al. Emerging Microbes and Infections (2016) 5, e10; doi:10.1038/emi.2016.10
Condition (partial list) TB riska
HIV/AIDS 10 - 100
Organ-transplant recipients 20 - 70
Chronic renal failure requiring dialysis 6.9 - 52.5
TNF-alpha blockers 1.6 - 25.1
Silicosis 2.8
Fibronodular disease on CXR 6 - 19
Diabetes mellitus 1.6 - 7.83
Smoking 2 – 3.4a Relative risk of TB compared to the general population
TB BasicsAnn Raftery, RN, BSN, PHN, MScCurry International Tuberculosis Center
TB Case Management and Contact Investigation IntensiveMarch 19-22, 2019 7
Latent TB Infection (LTBI)• Inactive tubercle bacilli in the
body
• Tuberculin skin test or interferon-gamma release assay (IGRA) test results usually positive
• Chest x-ray usually normal
• Sputum smears and cultures negative
• No symptoms
• Not infectious
• Not a case of TB
Active TB Disease• Active tubercle bacilli in the
body
• Tuberculin skin test or interferon-gamma release assay (IGRA) test results usually positive
• Chest x-ray may be abnormal
• Sputum smears and cultures may be positive
• Symptoms such as cough, fever, weight loss
• May be infectious before treatment
• A case of TB
Source: CDC. Transmission and Pathogenesis of Tuberculosis. Self-Study Modules on Tuberculosis. US Department of Health and Human Services. Atlanta, GA; 2008: 14. 13
TB Spectrum: Infection to Disease
Gideon and Flynn. Immunol Res. 2011 August ; 50(0): 202–21214
TB BasicsAnn Raftery, RN, BSN, PHN, MScCurry International Tuberculosis Center
TB Case Management and Contact Investigation IntensiveMarch 19-22, 2019 8
What are the classifications for TB?
15
TB Classification Scheme & Definitions
Class Stage of Disease Description
0 No TB exposure,
Not infected
No history of TB exposure. Negative tuberculin skin test (or IGRA)
1 Exposure, no evidence
of infection
History of TB exposure. Negative tuberculin skin test (or IGRA)
2 Latent TB infection, no
disease
Positive tuberculin skin test (or IGRA). No clinical, bacteriologic, or radiographic evidence of TB
3 TB, clinically active M. tuberculosis cultured (if performed). Clinical, bacteriologic, or radiographic evidence of current TB disease
4 TB, not clinically
active
History of episode(s) of TB OR Abnormal but stable radiographic findings , positive tuberculin skin test, negative bacteriologic studies (if done) AND no clinical or radiographic evidence of current disease
5 TB suspect
(aka presumptive TB)
Diagnosis pending. TB disease should be ruled in or out within 3 months
Adapted from: ATS/CDC. Diagnostic Standards and Classification of Tuberculosis in Adults and Children (2000). http://www.atsjournals.org/doi/full/10.1164/ajrccm.161.4.16141#.WA0Auk0zXIU
16
TB BasicsAnn Raftery, RN, BSN, PHN, MScCurry International Tuberculosis Center
TB Case Management and Contact Investigation IntensiveMarch 19-22, 2019 9
CDC TB Classifications:Immigrants and Refugees
Classification Description
No TB Normal TB screening examinations
Class A TB with waiver [Active] TB disease and have been granted a waiver
Class B1 TB, Pulmonary (PTB)
No treatment - H/o or findings suggestive of PTB but negative AFB sputum smears and cultures and are not diagnosed with [active TB disease] or can wait to have TB treatment started after immigration.
Completed treatment - Diagnosed with PTB and completed [treatment by] directly observed therapy prior to immigration.
Class B1 TB, Extra-pulmonary (EPTB)
Evidence of EPTB. The anatomic site of infection should be documented.
Class B2 TB, LTBI Evaluation
Positive TST (>10mm) but otherwise negative evaluation for TB.
Class B3 TB, Contact Evaluation
Recent contact of a known TB case.
Adapted from: CDC Immigration Requirements: Technical instructions for tuberculosis screening and treatment (2009). http://www.cdc.gov/immigrantrefugeehealth/ 17
Questions?
18
Classification System for Tuberculosis
TB Class
Type
Description
0 No TB exposure
Not infected • No history of TB exposure and no evidence of M. tuberculosis infection or disease
• Negative reaction to TST or IGRA
1 TB exposure
No evidence of infection • History of exposure to M. tuberculosis
• Negative reaction to TST or IGRA (given at least 8 to 10 weeks after exposure)
2 TB infection No TB disease
• Positive reaction to TST or IGRA
• Negative bacteriological studies (smear and cultures)
• No bacteriological or radiographic evidence of active TB disease
3 TB clinically active
• Positive culture for M. tuberculosis OR
• Positive reaction to TST or IGRA, plus clinical, bacteriological, or radiographic evidence of current active TB
4 Previous TB disease (not clinically active)
• May have past medical history of TB disease
• Abnormal but stable radiographic findings
• Positive reaction to the TST or IGRA
• Negative bacteriologic studies (smear and cultures)
• No clinical or radiographic evidence of current active TB disease
5 TB suspected • Signs and symptoms of active TB disease, but medical evaluation not complete
From Centers for Disease Control and Prevention. Table 2.8: TB Classification System. In: Chapter 2: transmission and pathogenesis of tuberculosis. Core Curriculum on Tuberculosis: What the Clinician Should Know. Atlanta, GA: 2011:40.
Websites Checked 10/20/2016
Resources on Tuberculosis (TB)
Centers for Disease Control and Prevention (CDC) Division of Tuberculosis Elimination (DTBE)
Guidelines: http://www.cdc.gov/tb/publications/guidelines/default.htm
Online Courses:
Self-Study Modules on Tuberculosis:
http://www.cdc.gov/tb/education/ssmodules/default.htm
Core Curriculum on Tuberculosis: What the Clinician Should Know:
http://www.cdc.gov/tb/education/corecurr/index.htm
Curry International Tuberculosis Center (CITC)
Medical Consultation Warmline: http://www.currytbcenter.ucsf.edu/consultation
877-390-6682 (toll-free)
Warmline inquiries can also be sent to the CITC email address, [email protected]
8:00 AM to 4:30 PM (Pacific Time), Monday through Friday (excluding holidays). Voicemail is available to record incoming messages 24 hours a day, 7 days a week.
Online Products: http://www.currytbcenter.ucsf.edu/products
(selected highlights only—check the web page for the full list)
Drug-Resistant Tuberculosis: A Survival Guide for Clinicians, 3rd edition
Radiographic Manifestations of Tuberculosis: A Primer for Clinicians, 2nd Edition
Tuberculosis Infection Control: A Practical Manual for Preventing TB
Websites Checked 10/20/2016
Curry International Tuberculosis Center (continued)
Online Courses & Presentations: http://www.currytbcenter.ucsf.edu/products
(selected highlights only—check the web page for the full list)
Medical Management of Tuberculosis
Pediatric Tuberculosis
Practical Solutions for TB Infection Control: Infectiousness and Isolation
TB Prevention in the HIV-infected Patient: Screening, Testing, and Treatment of LTBI
Tuberculosis Radiology Resource Page
Archived Webinars: http://www.currytbcenter.ucsf.edu/trainings/webinar-archive Classroom Trainings: http://www.currytbcenter.ucsf.edu/trainings
National Tuberculosis Controllers Association (NTCA)
Tuberculosis Nursing, 2nd Edition:
http://www.tbcontrollers.org/resources/tb-nursing- manual/#.VFuW7Wf4pws
Interjurisdictional Transfers (Form):
http://www.tbcontrollers.org/resources/interjurisdictional-transfers/#.VFuW3Wf4pws
Interjurisdictional Transfers (Contacts):
http://www.tbcontrollers.org/community/statecityterritory/#.WAmCLk0zXIU
California Tuberculosis Controllers Association (CTCA) California Department of Public Health/CTCA Joint Guidelines: http://www.ctca.org/
CTCA Directory: http://ctca.org/locations.html
Tuberculosis (TB)
Acronyms and Abbreviations
AFB acid-fast bacilli
ALT alanine aminotransferase
ARPE Aggregate Reports for Tuberculosis Program Evaluation
ART antiretroviral therapy
AST aspartate aminotransferase
AK amikacin
ATS American Thoracic Society
BCG Bacille Calmette-Guérin
BSC bio-safety cabinet
CBC complete blood count
CDC Centers for Disease Control and Prevention
CHOW community health outreach worker
CI contact investigation
CNS central nervous system
CM capreomycin
CS cycloserine
CXR chest x-ray
DTBE Division of Tuberculosis Elimination
DOT directly observed therapy
DST drug susceptibility testing
EMB (E) ethambutol
EPTB extra-pulmonary tuberculosis
ESRD end-stage renal disease
ETA ethionamide
FQN fluoroquinolone
IA injectable agent
IDSA Infectious Diseases Society of America
IGRA interferon gamma release assay
HIV human immunodeficiency virus
HPLC high performance liquid chromatography
HSC health & safety code
IGRA interferon gamma release assay
INH (I) isoniazid
IP infectious period
IUATLD International Union Against Tuberculosis and Lung Disease (The Union)
LFT liver function test
LJ Lowenstein-Jensen (type of TB culture medium)
LNZ linezolid
LTBI latent tuberculosis infection
M. tb Mycobacterium tuberculosis
MDDR molecular detection of drug resistance
MDR-TB multidrug-resistant tuberculosis
MFX moxifloxacin
MGIT mycobacteria growth indicator tube (TB culture method)
MIRU mycobacterial interspersed repetitive units (genotype method)
MMCP MediCal Managed Care Plan
MMWR Morbidity and Mortality Weekly Report
NAAT nucleic amplification test
NNRTI non-nucleoside reverse transcriptase inhibitor
NRTI nucleoside reverse transcriptase inhibitor
NTCA National Tuberculosis Controllers Association
NTIP National Tuberculosis Indicators Project
NTM nontuberculous mycobacteria
NTNC National Tuberculosis Nurse Coalition
PAS Para-aminosalicylate
PCR polymerase chain reaction
PPD purified protein derivative
PTB pulmonary tuberculosis
PZA (P) pyrazinamide
QFT-GIT QuantiFERON®-TB Gold In-Tube
RBT rifabutin
RFLP restriction fragment length polymorphism (genotype method)
RPT rifapentine
RIF (R) rifampin
RTMCC Regional Training and Medical Consultation Center
RVCT Report of Verified Case of Tuberculosis
SAT self-administered therapy
SM streptomycin
TNF-α tumor necrosis factor-alpha
TST tuberculin skin test
VDOT directly observed therapy performed via video
VNTR variable number of tandem repeats (genotype method)
XDR-TB extensively drug-resistant tuberculosis
ZN Ziehl-Neelson (AFB staining method)