Comparative study on safety of linezolid and vancomycin in the treatment of infants and neonates for Gram-positive bacterial infections

Vancomycin has been the common antimicrobial treatment for Gram-positive infection even in neonates and infants, while it is difficult to adjust blood concentration. Linezolid is also effective for Gram-positive infection, and is not necessary to monitor drug blood concentration. Primary objective of this study was to compare the safety of linezolid and vancomycin in infants and neonates for resistant Gram-positive infections. In total, 68 patients [linezolid group (32 patients); vancomycin group (36 patients)] treated with antimicrobials at Aichi Medical University Hospital between April 2014 and March 2017. Investigation items were as follows; sex, age, gestational age, birth weight, body weight, duration of treatment, Apgar score, laboratory data, rate of patients with blood transfusion, serum levels of vancomycin, disease type, concomitant medications, clinical isolates, adverse effects during antimicrobial treatment, antimicrobial susceptibility of isolated Gram-positive bacteria. Any substantially abnormal laboratory values were admitted in linezolid 40.6% (13/32) and vancomycin 41.7% (15/36) groups, respectively (p = 0.93). Platelet count was significantly decreased in only linezolid group (p = 0.03). Any adverse events during antimicrobial treatment were admitted in linezolid 46.9% (15/32) and vancomycin 58.3% (21/36) groups, respectively (p = 0.34). There were no notable differences in safety of linezolid and vancomycin groups even in neonates and infants. However, platelet count was significantly decreased in only linezolid group. The careful monitoring of platelet count would be required for infants and neonates receiving linezolid treatment.