Table 2.

TB preventive treatment eligibility and hepatotoxicity risk classification

Assessment	Hepatotoxicity risk category
	Low	Moderate	Moderate high	High
Definition
Risk factors Known viral hepatitis Known HIV infection Chronic liver disease Alcohol/kava excessive use* Age ≥60 years Test HBV positive*	No risk factors present	Any risk factor	Any risk factor	Any risk factor
ALT baseline test result (if any risk factors)	Not done	ALT<2 x ULN	ALT 2–3 x ULN and bilirubin <2xULN	ALT≥3 x ULN (or ALT 2–3 x ULN and bilirubin ≥2 x ULN)
Management
Monitoring while on TPT†	No repeat ALT	No repeat ALT	Repeat ALT after 3–4 weeks	Not applicable
Eligibility for TPT	YES	YES	YES	NO
Other reasons for TPT ineligibility	Diagnosed with TB disease TPT refused Pregnancy Allergies to TPT medicines

*Everyone ≥40 years with a positive TST who agrees to TPT and is otherwise at low risk is tested with an HBV rapid antigen test.

†Everyone on TPT receives adherence and adverse event counselling, a TPT passport (online supplemental files S4 and S5), as well as access to community-based treatment monitoring and adherence support.

‡Excessive use’ defined as ≥3 days/week and/or (for alcohol) getting drunk every week.

ALT, alanine aminotransferase; HBV, hepatitis B virus; TB, tuberculosis; TPT, TB preventive treatment; TST, tuberculin skin test; ULN, upper limit of normal.