1) Only screen for TB if the patient falls in a high-risk category on your history:
What is considered high-risk?
persons born in countries with increased TB prevalence
persons living in high-risk congregate settings (homeless shelters, incarcerated, health care workers)
2) Then, if you decide to screen - use IGRA (Quant Gold) or TST but not both.
IGRA/Quant Gold: single venous blood draw; no need to return for reading; use this if the patient has had a BCG vaccine(!); but expensive
TST/PPD: much cheaper; however false-positive if patient has had BCG vaccine; patient must return in 2-3 days for read (following Monday or Tuesday after clinic)
Use whichever test is indicated for your patient given their individual risk factors, likelihood of following up for a PPD read, and whether they received BCG as children. Ask your Chief TS if you have any questions.
References:
Fan T, Rogers A. Am Fam Physician (2017). 96(10):675-6.
Topic last updated Feb 22nd, 2018 by Jose Flores-Rodarte