What is the treatment for Cytomegalovirus (CMV) colitis in patients taking Humira (adalimumab)?

Treatment of Cytomegalovirus (CMV) Colitis in Patients Taking Humira (Adalimumab)

Intravenous ganciclovir 5 mg/kg twice daily for 5-10 days, followed by oral valganciclovir 900 mg daily for a total 2-3 week course, is the recommended treatment for CMV colitis in patients taking Humira, with consideration for tapering steroids but generally maintaining Humira therapy unless there is symptomatic disseminated CMV infection. 1, 2

Diagnosis of CMV Colitis

Before initiating treatment, proper diagnosis is essential:

• Gold standard: Colonic biopsy with histology and immunohistochemistry (IHC) showing characteristic "owl's eye" inclusions (92-100% specificity) 1, 2
• Supporting tests:
  • Colonic tissue CMV DNA PCR (improves sensitivity)
  • Whole blood leukocyte DNA PCR (65-100% sensitivity, 40-92% specificity)
  • Multiple biopsies recommended (minimum 11 for ulcerative colitis, 16 for Crohn's disease) 1

Treatment Algorithm

First-line Antiviral Therapy

1. Induction phase: IV ganciclovir 5 mg/kg twice daily for 5-10 days 1, 2
2. Maintenance phase: Oral valganciclovir 900 mg daily to complete a 2-3 week course 1
   • Earlier transition to oral therapy is possible depending on clinical response 1
   • Evidence suggests that a full 2-week IV course may be superior to shorter IV regimens or oral-only regimens in terms of clinical response and reduced colectomy rates 3

Management of Immunosuppression

• Humira (adalimumab): Generally can be continued during treatment for localized CMV colitis 1, 2
• Steroids: Should be tapered if the patient is on corticosteroids 1, 2
• Thiopurines: Consider temporary discontinuation as they have higher risk of CMV reactivation than TNF inhibitors like Humira 1
• Discontinue all immunosuppressants only in cases of symptomatic disseminated CMV infection (characterized by mononucleosis-like syndrome with fever, malaise, leukopenia, low platelet count, and elevated liver enzymes) 1, 2

Alternative Treatment for Ganciclovir Intolerance/Resistance

• Foscarnet: For ganciclovir-intolerant patients or in uncommon cases of ganciclovir-resistant CMV 1, 2
  • Requires strict monitoring of renal function and electrolytes
  • Concomitant normal saline administration may reduce risk of renal damage
  • May cause genital ulceration; careful hygiene recommended

Monitoring During Treatment

• Laboratory monitoring: Complete blood counts and electrolytes twice weekly during induction and weekly thereafter 2
• Watch for side effects: Neutropenia and thrombocytopenia (common with ganciclovir) 1
• Clinical response: Assess for resolution of symptoms; consider repeat colonoscopy in non-responsive cases 2
• Viral clearance: CMV clearance may parallel achievement of remission induced by immunosuppressants, even without antivirals (more frequent with low viral load) 1

Special Considerations

• Multidisciplinary approach: Engage infectious disease specialists early, especially for complex cases 1
• Surgical evaluation: Consider subtotal or partial colectomy for severe conditions (toxic megacolon, fulminant colitis, perforation) 2, 4
• Viral load: Higher colonic viral load correlates with higher risk of colectomy, supporting benefit of antiviral therapy, though exact threshold for treatment is unknown 1
• TNF inhibitors like Humira: Generally considered to have lower risk of CMV reactivation than thiopurines 1

Pitfalls to Avoid

• Delayed diagnosis: CMV colitis should be considered in all patients with acute severe IBD flares on immunosuppression 1, 2
• Premature discontinuation: Early cessation of antiviral therapy can lead to relapse 2
• Underestimating severity: Can result in higher morbidity and mortality 2
• Inadequate monitoring: Failure to monitor for neutropenia, thrombocytopenia, and renal dysfunction during treatment 1, 2
• Inappropriate immunosuppression management: Unnecessary discontinuation of all immunosuppressants in localized disease, or failure to discontinue in disseminated disease 1, 2