LTBI - Who to Test-Who to Treat

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Who to Test-Who to Treat

Test persons at high risk for tuberculosis infection and those at high risk for progression to TB disease if infected with M.tb. Before starting treatment perform initial clinical evaluation, including radiologic studies to rule out TB disease.

• Contacts* <5 years of age♥
• Contacts* who are HIV-infected or otherwise immunosuppressed

IGRA+
TREAT

TST <5 mm
TRE
ATusing “window prophylaxis”

TST 5 mm
TREAT

TST 10 mm
TREAT

TST 15 mm
TREAT

• HIV-infected
• Immunosuppressed persons (e.g. TNF-alpha blockers, organ transplant medications)
• Contact*of TB case (not immunosuppressed)
• Fibrotic changes on chest radiograph (adults)

IGRA+
TREAT

TST <5 mm
Do Not Treat

TST 5 mm
TREAT

TST 10 mm
TREAT

TST 15 mm
TREAT

• Recent arrival from  TB endemic country
• Injection drug user
• Resident/employee institutional setting§
• Mycobacteria lab personnel
• High-risk clinical conditions‡
• Persons <18 years exposed to high-risk adults
• Child <4 years of age

IGRA+
TREAT

TST <5 mm
Do Not Treat

TST 5 mm
Do Not Treat

TST 10 mm
TREAT

TST 15 mm
TREAT

No known risk factors (testing discouraged)

IGRA+
TREAT

TST <5 mm
Do Not Treat

TST 5 mm
Do Not Treat

TST 10 mm
Do Not Treat

TST 15 mm
Consider Treatment

 * All contacts should receive an initial  TST or IGRA and if test is negative should be tested again 8 -10 weeks after last exposure to infectious  TB case. Window prophylaxis: Start LTBI treatment even if TST or IGRA is negative in contacts who are <5 years of age, HIV-infected, or otherwise immunosuppressed and test again  8-10 weeks after last exposure. Treatment may be discontinued in a healthy child if the second test is negative.  Treatment may be continued in HIV+ and other immunosuppressed individuals  if exposure to TB was substantial.
§ Institutional settings: An increase in reaction size of ≥10 mm within 2 years should be considered a TST conversion indicative of recent infection with M.tb.
High-Risk clinical conditions: Silicosis, diabetes mellitus, chronic  renal failure,  some hematologic  disorders (e.g.,  leukemias and lymphomas),  other specific malignancies (e.g., carcinoma of the head, neck or lung), weight loss of ≥10% of ideal body weight, gastrectomy, and jejunoileal bypass)
Pediatrics:  TST is the preferred method for testing children under the age of 5 years
Pregnancy: Perform  shielded chest radiograph to rule out TB disease. Treat   LTBI, even during first trimester,  if either HIV-infected or recent M.tb infection. Otherwise, wait until 2-3 months post-partum.
BCG vaccination  Disregard BCG vaccination when testing and treating for LTBI. A positive TST result  indicates need to treat LTBI. IGRA  result   is not affected by prior BCG vaccination.