delayed tb diagnosis thomas r. navin md chief, surveillance, epidemiology, and outbreak...
TRANSCRIPT
Delayed TB Diagnosis
Thomas R. Navin MDChief, Surveillance, Epidemiology, and Outbreak Investigations BranchDivision of Tuberculosis EliminationCDC
Test of Baseline Knowledge
How many patients are evaluated for TB each year in the United States?
Are the number of persons evaluated going down or staying stable?
Are delays in TB diagnosis getting worse?
Are delays worse for racial/ethnic minorities?
Patients Evaluated for TB at CDC-funded Public Health Laboratories,
2008-2009
2008 2009 % change
Patients evaluated for TB
103,708
97,568 -5.9%
Patients with cultures positive for M. tuberculosis
4,972 4,217 -15.2%
Ratio of patients evaluated to patients diagnosed with TB
21 : 1 23 : 1
Preliminary Results from TBESC Task Order 23:National Study of Early Diagnosis of TB in the African-American Community
Co-Principal Investigators:
Dolly Katz, Ph.D., CDCRachel Royce, Ph.D., M.P.H., RTI InternationalCharles Wallace, Ph.D., Texas Department of Health
4
Measuring TB Diagnostic Delay
Months from Symptom Onset to Diagnosis
(N=346)
5
Race Mean (SD) Median
African-American 4.4 (6.1) 2White 19.7 (48.4) 4p=0.04
Months from Symptom Onset to First Medical Care: Patient Delay
(N=346)
6
Race Mean (SD) Median
African-American 2.4 (5.2) 1White 9.2 (29.5) 1p=0.8
Months from First Medical Care to Diagnosis: Provider Delay
(N=346)
7
Race Mean (SD) MedianAfrican-American 2.2 (3.5) 1White 4.5 (4.5) 1p=0.4
Summary of Findings from Task Order 23: Study of Patient and Provider Delay
Snap shot in time (rather than trend over time)
Both patient and provider delay observed
Delay not worse for African Americans compared with whites
Contribution of Provider Diagnostic Delay to 27 TB Outbreaks
Investigated by CDC*
Contributing factors
Number of Outbreaks where item was
considered a contributing factor
Prolonged infectious period
24
Provider-related diagnostic delay
12
Patient-related delay in access to care
6
* From: Mitruka et al., EID 2011;17(3):425
National TB Surveillance System:
Trends in culture-positive, smear-negative pulmonary TB
Data from Recent TB OutbreakCases by sputum smear status
Mar Apr May Jun Jul Aug Sep Oct0
1
2
3
4
5
6
Smear-negativeSmear-positive
TB
Cases
Treatment Start Date
Culture-confirmed Pulmonary TB bySputum Smear Status, United States
2000-2009
TB
Cases
0
1000
2000
3000
4000
5000
Smear positive
Smear negative
Smear status unknown/not done
Proportion of Pulmonary TB Cases* That Are Sputum Smear-Negative,
United States, 2000-2009
•Culture-positive TB cases
20002001200220032004200520062007200820090%
20%
40%
60%
80%
100%
Proportion of Pulmonary TB Cases* That Are Sputum Smear-Negative,
by Race/EthnicityUnited States, 2000-2009
TB Case Count Date* Culture-positive TB cases
20002001200220032004200520062007200820090%
20%
40%
60%
80%
100%
WhiteBlackHispanic
Test of What You Have Learned
How many patients are evaluated for TB each year in the United States?
Are the number of persons evaluated going down or staying stable?
Are delays in TB diagnosis getting worse?
Are delays worse for racial/ethnic minorities?
Test of What You Have Learned
How many patients are evaluated for TB each year in the United States?
100,000 persons evaluated each year at public health labs alone
Ratio of evaluated-to-diagnosed: 20+
Are the number of persons evaluated going down or staying stable?
Number is going down, but ratio of evaluated-to-diagnosed may be going up
Test of What You Have Learned
Are delays in TB diagnosis getting worse?
Data are not good, but no evidence of worsening
Are delays worse for racial/ethnic minorities?
Data are not good, but no evidence of a difference
Getting Physicians to “Think TB” is asking them to look for a needle in a
haystack
Community-acquired pneumonia
Lung CA TB (0.3%)
Can Physicians be Educated to “Think TB”?
• As TB rates decline, general medical expertise and education targeted at TB will decline
• Untargeted campaigns may not be successful
• “Think TB” campaigns may have impact in targeted situations:
• In high-risk communities• During outbreaks
Can Physicians be Educated to “Think TB”?
Challenges During TB Outbreaks
• Most media stories about TB “outbreaks” describe contact investigations at schools
• Most contact investigations at schools do not detect additional TB cases
• Health Departments often work hard to keep information on large TB outbreaks out of media
Outbreak-associated TB cases can make up a significant portion of TB cases in a community and can continue for years
0
5
10
15
20
25
Outbreak Associated TB Cases, 2002-2010 (N=109)
No.
of
cases
a As of August 2010