[Fulminant Clostridioides difficile infection during treatment with FLT3 inhibitor for acute myeloid leukemia]

Area of Science:

• Hematology
• Infectious Diseases
• Oncology

Background:

• A patient with FLT3-TKD mutation-positive acute myeloid leukemia (AML) experienced relapse during venetoclax/azacitidine consolidation therapy.
• Salvage therapy was initiated with gilteritinib, a targeted treatment for FLT3-mutated AML.

Observation:

• The patient developed febrile neutropenia shortly after starting gilteritinib, which resolved with antibiotics.
• Subsequently, the patient presented with severe watery diarrhea, leading to a diagnosis of Clostridioides difficile infection (CDI).
• Initial treatment with intravenous metronidazole was complicated by renal dysfunction, hypotension, and hypoxemia, with CT scans revealing significant gastrointestinal and fluid abnormalities.

Findings:

• Fulminant CDI was diagnosed in an acute myeloid leukemia patient during gilteritinib salvage therapy.
• Intravenous metronidazole failed to resolve severe symptoms and led to complications.
• Fidaxomicin administration resulted in a clinical response and successful management of the fulminant CDI.

Implications:

• This case underscores the potential for severe Clostridioides difficile infection during intensive chemotherapy for acute myeloid leukemia.
• Fidaxomicin demonstrates efficacy in treating fulminant CDI, even in immunocompromised patients with significant complications.
• The successful management highlights the importance of considering and effectively treating opportunistic infections in AML patients undergoing novel therapeutic regimens.