True-positives vary with patients background |
5mm induration is positive in patients with |
- Known or suspected HIV
- An abnormal CXR
- Close contact with person with active TB
- Organ transplant patients
|
> 10 mm induration is positive in: |
- Resident/employees of long term care facilities
- IV drug abusers
- Immigrants from an area with high incidence
- Certain minority groups (Hispanics, African-Americans, native Americans)
- Children less then 4 years old
- Children with TB exposure
|
> 15mm induration is positive in all others[5] |