🩹 Biologic Infection-Risk Screening Simulator

Latent TB Screening — IGRA and Tuberculin Skin Testing

All patients are screened for latent TB before biologic therapy begins.

• ~90%: IGRA sensitivity (placeholder figure)
• ≥5mm: TST cutoff (placeholder figure)
• Pre-therapy: Screening timing (placeholder figure)
• Annual: Repeat testing (placeholder figure)

Why screening precedes biologic initiation

Placeholder: latent TB must be identified before immune suppression begins.

Hepatitis B and C Serology Panel

HBsAg, anti-HBc, and HCV antibody testing detect chronic or resolved infection.

• Active: HBsAg marker (placeholder figure)
• Past exposure: Anti-HBc marker (placeholder figure)
• Screening: HCV antibody (placeholder figure)
• ~296M: Global HBV carriers (placeholder figure)

Serology markers and chronic carrier detection

Placeholder: serology distinguishes active, resolved, and occult hepatitis infection.

How Biologics Suppress Granuloma and Viral Control

TNF-α blockade destabilizes the granuloma wall containing dormant bacteria.

• Granuloma upkeep: TNF-α role (placeholder figure)
• HBV flare: B-cell depletion risk (placeholder figure)
• Elevated: JAK inhibitor risk (placeholder figure)
• Weeks-months: Onset of risk (placeholder figure)

Mechanism of immune suppression on latent reservoirs

Placeholder: cytokine blockade weakens containment of dormant pathogens.

Reactivation Risk of Latent TB and Hepatitis B

Untreated latent infection can reactivate rapidly once therapy begins.

• ~10-15%/yr: TB reactivation (placeholder figure)
• 10-40%: HBV reactivation (placeholder figure)
• Weeks: Time to flare (placeholder figure)
• Elevated: Mortality if missed (placeholder figure)

Clinical consequences of missed reactivation

Placeholder: reactivation can be severe and sometimes fatal if unscreened.

Prophylaxis Before Starting Biologic Therapy

Isoniazid or antiviral prophylaxis is started before or with biologic therapy.

• 9 months: INH course (placeholder figure)
• Entecavir/TDF: Antiviral choice (placeholder figure)
• ~4 weeks: Delay to biologic (placeholder figure)
• Ongoing: Monitoring (placeholder figure)

Preemptive therapy protocol

Placeholder: prophylaxis clears infection risk before immune suppression starts.

Placeholder: screening and prophylaxis together prevent most reactivation events.