P4439 - White Blood Cell Chronicles: Mesalamine’s Dual Effect on Leukopenia and Neutropenia.

Bibhuti Adhikari, MD¹, Richard Mitchell, MD¹, Aaron Walfish, MD¹, Maliyat M Matin, DO², Woo Suk Kim, MD¹, Bobby Thomas, MD¹, Tasur Seen, MD¹, Anastasia Novikov, MD², Nirali Sheth, MD², Genanew Bedanie, MD^1
1Elmhurst Hospital Center / Icahn School of Medicine at Mount Sinai, Queens, NY; ²Elmhurst Hospital Center / Icahn School of Medicine at Mount Sinai, Elmhurst, NY

Introduction: Mesalamine is frequently used in inducing or maintaining remission in mild to moderate ulcerative colitis and is generally well tolerated. Neutropenia and Leukopenia are rare side effects of treatment with Mesalamine with only few cases reported in the literature. The time of onset ranges from 2 weeks to 1 year from initiation of therapy. We report a case of neutropenia and leukopenia 6 weeks after post induction therapy with oral and rectal mesalamine in a 68 y.o female with newly diagnosed ulcerative colitis.

Case Description/Methods: A 68 y.o female was admitted to hospital for persistent diarrhea, found to have leukocyte count of 8000 cells/mm3, Hemoglobin 11.4 g/dl, Absolute Neutrophil of 4310 cells/mm3, Neutrophil % 53.5. Elevated ESR and CRP. CTAP concerning Pan colitis. Rectal biopsy demonstrating nonspecific colitis without chronicity. Repeated colonoscopy with continuous and circumferential inflammation in sigmoid, ascending colon and rectum, Staging Mayo score 3. She was then started on oral and rectal mesalamine for induction therapy as well as IV steroid during the hospital course later transitioned to oral steroid on discharge.



On her follow up visit at GI clinic, blood chemistry concerning the drop in her neutrophil count to 850 and Wbc count of 2300/mm3 without any symptoms of infection. Patient was noted to have been compliant with her home dose of oral and rectal mesalamine as well as steroid for a total duration of 6 weeks before presenting to GI clinic. Given a rare but known side effect of neutropenia secondary to mesalamine, Mesalamine therapy stopped immediately which showed slowly recovering neutropenia, neutrophil count increased from 850 to 1100/mm3 within a few days after mesalamine discontinuation. Pt was started on entyvio (vedolizumab) for newly diagnosed UC being Mayo 3 on recent colonoscopy.

Discussion: Most patients tolerate mesalamine but leukopenia and neutropenia are serious adverse reactions that can occur. These can be overlooked as renal impairment is more commonly reported. Given the risk of severe infections, periodic monitoring of blood count is important and prompt discontinuation of the drug should occur when cytopenias are observed. Majority of cases are reversed when mesaline was discontinued as was the case for our patient. Hematological recovery is generally slow, probably because of the central immune mediated mechanism of toxicity. However, we observed quick recovery within days of drug discontinuation.



Disclosures:


Bibhuti Adhikari, MD¹, Richard Mitchell, MD¹, Aaron Walfish, MD¹, Maliyat M Matin, DO², Woo Suk Kim, MD¹, Bobby Thomas, MD¹, Tasur Seen, MD¹, Anastasia Novikov, MD², Nirali Sheth, MD², Genanew Bedanie, MD¹. P4439 - White Blood Cell Chronicles: Mesalamine’s Dual Effect on Leukopenia and Neutropenia., ACG 2024 Annual Scientific Meeting Abstracts. Philadelphia, PA: American College of Gastroenterology.