Vol.59 No.2 March 2011
Linezolid efficacy and safety: A retrospective Tokyo study
1)Department of Practical Pharmacy, Keio University Faculty of Pharmacy, 1-5-30 Shibakoen, Minato-ku, Tokyo, Japan
2)Current by: Department of Medicine, National Hospital Organization Kurihama Alcoholism Center
3)Department of Medicine, National Hospital Organization Tokyo Medical Center
4)Department of Pediatrics, National Hospital Organization Tokyo Medical Center
5)Current by: Department of Infection Control Center, Keio University of Medicine
Abstract
Linezolid(LZD), an anti-methicillin-resistant Staphylococcus aureus(MRSA) agent, exhibits potent clinical effects on MRSA infection, but reported by causes thrombocytopenia as a side effect. We retrospectively studied LZD efficacy and safety in 106 subjects (77 men and 29 women with a mean age of 65.0 years (18 to 91))treated with LZD between 2006 and 2008. We studied their backgrounds, reasons for LZD administration, anti-MRSA agents administered prior to LZD therapy, and laboratory data based on medical records. Mean administration was 16.4 days (1 to 78). LZD was mostly administered for poor or no response to anti-MRSA therapy. Vancomycin and other anti-MRSA agents were administered to 60 of the 106 subjects.
In 49, clinical efficacy was evaluated by infection control doctor, who found 61% efficacy. In 25 (37 episodes) of the 106, LZD side effects were seen within 14 days after administration start. During LZD therapy, platelet counts decreased to less than 100,000 /μL in 10 of the 54, hemoglobin to less than 11 g/dL in 3 of the 6, and leukocytes to less than 4,000 /μL in 12 of the 70. Among factors involved in thrombocytopenia in those whose platelet counts were within normal range (150,000 to 350,000 /μL) before LZD therapy. In the thrombocytopenia group, administration was longer (p=0.017), and subjects were older (p=0.002).
These results suggest that hematological examination is important for detecting thrombocytopenia early stage after LZD administration start. Adverse thrombocytopenic effects should be carefully observed, particularly in long-term LZD administration and in LZD administration for old subjects.
Key word
linezolid, MRSA, thrombocytopenia
Received
August 27, 2010
Accepted
December 27, 2010
Jpn. J. Chemother. 59 (2): 163-171, 2011
