Complete medical records were available for 68 patients; of those, the occurrence of arthralgias and myalgias could not be assessed in 18 (26.5%) because the patients were intubated, sedated, and paralyzed, or they were young children who could not communicate the presence of pain. Mean age of the 50 evaluable patients was 48.4 ± 14.4 years; only two were younger than 18 years. Two children received quinupristin-dalfopristin; one, an infant, was treated on three separate occasions, for a total of 57 days of therapy. Because he was only 3 months old at the start of therapy, it was impossible to discern whether he experienced arthralgias or myalgias during therapy. The second child received quinupristin-dalfopristin for 20 days. Although 5 years old, this child was noncommunicative. Thus, both pediatric patients were placed in the unassessable group.
Twenty-five (50%) of the 50 patients experienced arthralgias or myalgias. We could not determine from the medical records of most patients whether the symptoms were primarily muscular or articular; complaints were generally of diffuse aching and pain that was not localized to joints or muscle groups. All patients were given quinupristin-dalfopristin 7.5 mg/kg as an intravenous infusion every 8 hours. The dosage for two adult patients was decreased later to 5 mg/kg every 8 hours in an effort to reduce their arthralgias and myalgias.
Onset of symptoms occurred an average of 3.1 ± 2 days (range 1-5 days) after therapy was started. For the 13 patients who completed therapy despite having arthralgias or myalgias, these symptoms resolved a mean of 4.2 ± 2 days after quinupristin-dalfopristin was stopped. Symptoms improved in the two patients whose quinupristin-dalfopristin dosage had been decreased, and two patients refused further infusions because of the severity of their symptoms. Of the 25 patients who developed arthralgias or myalgias, 12 died as a result of underlying disease processes; of the 25 who had no arthralgias or myalgias, nine died.
Univariate analysis showed the following significant risk factors for arthralgias or myalgias associated with quinupristin-dalfopristin: female sex, chronic liver disease, receipt of liver transplant, major surgery, elevated bilirubin level at baseline, and receipt of either mycophenolate and cyclosporine ( Table 1 ). A multivariate logistic regression model demonstrated that chronic liver disease, receipt of liver transplant, elevated bilirubin level at baseline, and receipt of either mycophenolate or cyclosporine remained independently associated with development of myalgias and arthralgias during quinupristin-dalfopristin therapy ( Table 2 ).
Pharmacotherapy. 2003;23(2) © 2003 Pharmacotherapy Publications
Copyright © 1999, Pharmacotherapy Publications, Inc., All rights reserved.
Cite this: Risk Factors for Arthralgias or Myalgias Associated With Quinupristin-Dalfopristin Therapy - Medscape - Feb 01, 2003.