Pre-Biologic Workup in IBD
Before initiating biologic therapy in IBD, you must screen for tuberculosis and hepatitis B, assess vaccination status, and obtain baseline laboratory tests including complete blood count and liver function tests. 1
Mandatory Infectious Disease Screening
Tuberculosis Screening
- Screen all patients for latent tuberculosis before starting any biologic therapy due to reactivation risk 1
- Acceptable screening methods include:
- Tuberculin skin test (TST)
- Interferon-gamma release assay (IGRA)
- Chest X-ray 2
- Screening rates have improved to 90-97% in recent years, though adherence remains imperfect 2
Hepatitis B Screening
- Screen for hepatitis B virus due to reactivation risk with immunosuppressive therapies 1
- Despite improvements, hepatitis B screening remains suboptimal (36-49% in recent cohorts), representing a critical gap in pre-biologic assessment 2
Vaccination Assessment and Updates
Update all vaccinations before initiating biologic therapy, as live vaccines are contraindicated once immunosuppression begins 1, 3:
- Pneumococcus 1
- Influenza (annual) 1
- COVID-19 1
- Herpes zoster (recombinant vaccine preferred) 1
- Respiratory syncytial virus 1
- Human papillomavirus 1
This vaccination strategy is essential because over 70% of IBD patients will receive immune-modifying therapies that increase infection risk 3
Baseline Laboratory Assessment
Standard Laboratory Tests
Obtain baseline labs concordant with medication labels 1:
- Complete blood count - required before immunomodulators or JAK inhibitors 1
- Liver function tests - required before immunomodulators or JAK inhibitors 1
- Lipid panel - specifically required before JAK inhibitor initiation, with repeat testing after therapy starts 1
Comorbidity Assessment
Disease-Specific Considerations
Evaluate for comorbidities that may be exacerbated by specific biologic classes 1:
- TNF antagonists require particular caution in patients with specific comorbid conditions (though the guideline notes this consideration without exhaustive detail) 1
- Patients with comorbidities have significantly higher risk of serious infections (hazard ratio 3.94), warranting heightened vigilance 2
Confirmation of Active Inflammation
Before prescribing biologics, confirm active inflammation through objective measures, as up to one-third of CD patients have concomitant functional symptoms 1:
- Biochemical markers: C-reactive protein or fecal calprotectin 1
- Structural assessment: Ileocolonoscopy or imaging (CT, MR enterography, or intestinal ultrasound based on availability) 1
Common Pitfalls to Avoid
- Incomplete hepatitis B screening remains the most significant gap, with screening rates below 50% in many centers 2
- Delaying vaccination updates until after biologic initiation, which precludes use of live vaccines 3
- Failing to document baseline labs specific to the chosen medication class, particularly lipid panels for JAK inhibitors 1
- Initiating therapy without objective confirmation of inflammation, risking treatment of functional symptoms rather than active IBD 1