Patients with rheumatic diseases must be screened prior to initiating advanced therapies such as biologics and JAK Inhibitors.
Screening for Latent Tuberculosis (TB)
Latent TB is defined as a TB skin test ≥ 5 mm with a clear chest XRay, and no other signs/symptoms of active TB infection. Patients with latent TB must receive prophylactic therapy prior to initiating JAK inhibitors and most biologics. Depending on the regimen, prophylactic therapy may vary form 3 – 9 months. JAK Inhibitors / biologics can be started after one month of prophylaxis is received.
- History, physical examination
- TB Skin Test
- In specific cases, an Interferon-gamma release assays (IGRA) should be considered if:
- Suspected false-positive TBST (eg. positive TBST in a patient who received BCG)
- Suspected false-negative (eg. negative TBST in a patient with high epidemiological risk)
Screening for Hepatitis B
- Hep B sAg: indicates active viral replication. Patients should be treated prior to initiating biologic / JAK Inhibitor therpay.
- Hep B cAb: indicates prior exposure to Hepatitis B virus, and carries a risk of reactivation with biologics / JAK inhibitors. Patients should therefore be referred for evaluation and treatment.
- Hep B sAb: indicates immunity to Hepatitis B
Screening for Hepatitis C
- Hep C Ab: indicates exposure and implies infection with Hepatitis C.