5
LTBI Testing Strategy
Likely to be Infected
Low to Intermediate Risk of Progression (TST ≥10 mm)
Likely to be Infected
High Risk of Progression
(TST ≥5 mm)
Unlikely to be Infected (TST >15 mm)
Risk of Developing Tuberculosis if Infected
Low Intermediate (RR1.3–3)
High (RR 3–10)
No risk factors Clinical predisposition
Diabetes
Chronic renal failure
Intravenous drug use
Children age <5
HIV infection
Immunosuppressive
therapy
Abnormal CXR consistent
with prior TB
Silicosis
Benefit of Therapy
Not demonstrated Yes
