Assessing potential risk factors for metamizole-induced leukopenia

Birgit Brüne; Sarah Sonderer; Maria Bösing; Simona Hübner; Kanchan Dongre; Selina Späni; Andreas Holboro; Jörg D Leuppi; Anne B Leuppi-Taegtmeyer

doi:10.1177/20420986241275255

Assessing potential risk factors for metamizole-induced leukopenia

Ther Adv Drug Saf. 2024 Sep 18:15:20420986241275255. doi: 10.1177/20420986241275255. eCollection 2024.

Authors

Birgit Brüne¹, Sarah Sonderer^{1

2}, Maria Bösing^{1

2}, Simona Hübner¹, Kanchan Dongre³, Selina Späni⁴, Andreas Holboro^{2

5

6}, Jörg D Leuppi^{1

2}, Anne B Leuppi-Taegtmeyer^{7

3

4}

Affiliations

¹ University Center of Internal Medicine, Cantonal Hospital Baselland, Liestal, Switzerland.
² University of Basel, Basel, Switzerland.
³ Department of Patient Safety, Medical Directorate, University Hospital Basel, Basel, Switzerland.
⁴ Clinical Pharmacology and Clinical Pharmacy, Hospital Pharmacy, Cantonal Hospital Baselland, Liestal, Switzerland.
⁵ Regional Blood Transfusion Centre, Swiss Red Cross, Basel, Switzerland.
⁶ Division of Hematology, University Hospital Basel and University of Basel, Basel, Switzerland.
⁷ University of Basel, Spitalstrasse 22, Basel 4031, Switzerland.

Abstract

Background: Metamizole is a non-opioid analgesic agent that can rarely cause agranulocytosis, a severe form of leukopenia.

Objectives: The aim of this study was to assess previously identified potential risk factors for the development of metamizole-induced leukopenia.

Design: A retrospective, observational, matched case-control study was performed in a single-center setting.

Methods: Patients who developed leukopenia in the setting of metamizole therapy were included as cases and matched 1:3 on the basis of age and sex to control patients who did not develop leukopenia when treated with metamizole. The data were obtained from the medical records of patients hospitalized at Cantonal Hospital Baselland between 2015 and 2020. Univariate and multivariate analyses were performed.

Results: Eighty-six cases and 258 matched controls aged between 18 and 102 years were included. Fifty-seven percent were female. Previous leukopenic episodes (odds ratio (OR): 4.02, 95% CI: 1.95-8.28, p < 0.001) and a history of penicillin allergy (OR: 2.49, 95% CI: 1.03-6.03, p = 0.044) were found to be independent risk factors for metamizole-induced leukopenia.

Conclusion: A history of previous leukopenic episodes and a history of penicillin allergy were confirmed as risk factors for metamizole-induced leukopenia. In our opinion, metamizole should be avoided in patients with these risk factors.

Keywords: agranulocytosis; dipyrone; leukopenia; metamizole; risk factors.

Plain language summary

Assessing potential risk factors for metamizole-induced leukopenia Background: Metamizole is a medication used to treat pain and fever. It carries a risk of developing the side effect of a low white blood cell count (leukopenia). Researchers have identified certain risk factors which predispose some, but not all, people to develop this side effect. We undertook this study to examine these risk factors in more detail.

Method: We compared hospitalized patients treated with metamizole who developed leukopenia, with similar hospitalized patients who did not develop this side effect.

Results: It was observed that patients were more likely to develop leukopenia under metamizole therapy if they: - had previous episodes of leukopenia - were under cytostatic/immunosuppressive therapy (for example drugs used to treat cancer or autoimmune conditions) - had a history of penicillin allergy.

Conclusion: These findings will help in identifying people who are at risk of developing this serious side effect, so that they can be given a medication for pain or fever that suits them better.