Lea Blaser1, Hala Hassna1, Sarah Hofmann1, Andreas Holbro2, Manuel Haschke3, Alexandra Rätz Bravo3, Andreas Zeller4, Stephan Krähenbühl5, Anne Taegtmeyer5. 1. Division of Clinical Pharmacology and Toxicology, University and University Hospital Basel, Switzerland. 2. Division of Haematology, University Hospital Basel, Switzerland. 3. Division of Clinical Pharmacology and Toxicology, University and University Hospital Basel, Switzerland, and Regional Pharmacovigilance Centre, University Hospital Basel, Switzerland. 4. Centre of Primary Health Care, University of Basel, Switzerland. 5. Division of Clinical Pharmacology and Toxicology, University and University Hospital Basel, Switzerland and Regional Pharmacovigilance Centre, University Hospital Basel, Switzerland.
Abstract
AIMS OF THE STUDY: The aim of this study was to identify possible risk factors for the development of leucopenia associated with metamizole use. METHODS: A retrospective case-control study was performed. Cases of metamizole-associated leucopenia managed at a single centre (2005-2013) were characterised and compared with matched controls who took metamizole without developing complications. RESULTS: Fifty-seven cases and 139 controls were identified. Of the cases, 32 were postoperative and these were compared to age-, sex- and ward-matched postoperative controls (n = 64). The remaining cases (n = 25) were compared to sex-matched, non-postoperative controls (n = 75). The number of patients with a positive allergy history was higher among postoperative cases than controls (p = 0.004) as was the number with previous leucopenic episodes (p = 0.03). The prevalence of diagnosed hepatitis C infection was 9% among all cases compared with 1% among all controls (p = 0.005). The use of concomitant cytostatic agents (even at immunosuppressive doses) was significantly higher among non-postoperative cases than controls (p = 0.011). There was no association between renal function and the development of leucopenia. CONCLUSIONS: A history of allergies, previous leucopenic episodes, hepatitis C infection and concomitant cytostatic agents are possible risk factors for leucopenia associated with metamizole use.
AIMS OF THE STUDY: The aim of this study was to identify possible risk factors for the development of leucopenia associated with metamizole use. METHODS: A retrospective case-control study was performed. Cases of metamizole-associated leucopenia managed at a single centre (2005-2013) were characterised and compared with matched controls who took metamizole without developing complications. RESULTS: Fifty-seven cases and 139 controls were identified. Of the cases, 32 were postoperative and these were compared to age-, sex- and ward-matched postoperative controls (n = 64). The remaining cases (n = 25) were compared to sex-matched, non-postoperative controls (n = 75). The number of patients with a positive allergy history was higher among postoperative cases than controls (p = 0.004) as was the number with previous leucopenic episodes (p = 0.03). The prevalence of diagnosed hepatitis C infection was 9% among all cases compared with 1% among all controls (p = 0.005). The use of concomitant cytostatic agents (even at immunosuppressive doses) was significantly higher among non-postoperative cases than controls (p = 0.011). There was no association between renal function and the development of leucopenia. CONCLUSIONS: A history of allergies, previous leucopenic episodes, hepatitis C infection and concomitant cytostatic agents are possible risk factors for leucopenia associated with metamizole use.