Ipilimumab-associated colitis or refractory Clostridium difficile infection?

Area of Science:

• Oncology
• Immunology
• Gastroenterology

Background:

• Diarrhoea is a common immune-related adverse effect of ipilimumab, an anti-CTLA4 monoclonal antibody used in cancer therapy.
• Distinguishing ipilimumab-associated colitis from Clostridium difficile infection (CDI) is crucial for appropriate patient management.
• Fecal microbiota transplantation (FMT) is effective for refractory CDI but not indicated for drug-induced colitis.

Observation:

• A patient with refractory diarrhoea, initially suspected to be CDI, was referred for FMT.
• Detailed history revealed recent ipilimumab exposure, leading to a diagnosis of ipilimumab-associated colitis.
• C. difficile testing was negative, supporting the suspicion of drug-induced colitis.

Findings:

• The patient's diarrhoea was successfully managed with fluid resuscitation and corticosteroids.
• FMT was not administered due to the confirmed diagnosis of ipilimumab-associated colitis.
• The patient remained symptom-free at a 9-month follow-up.

Implications:

• This case underscores the importance of a thorough drug history in patients presenting with severe diarrhoea during cancer immunotherapy.
• Accurate diagnosis is essential to guide appropriate treatment, avoiding unnecessary or ineffective interventions like FMT for non-infectious causes.
• Steroid therapy can be highly effective in managing ipilimumab-induced colitis.