Methicillin-Susceptible S aureus Outcomes Similar With Low- vs High-Dose Ceftriaxone

Increasing the daily dose of ceftriaxone for the treatment of methicillin-susceptible Staphylococcus aureus (MSSA) infection did not increase adverse event rates, according to study results published in BMC Infectious Diseases.

A retrospective study was conducted to compare the incidence neutropenia, thrombocytopenia, and increased liver enzymes in patients with MSSA who did vs did not switch from low-dose (2 g) to high-dose (4 g) ceftriaxone. Researchers evaluated patient records collected from the Chelsea and Westminster Hospital and West Middlesex Hospitals in the United Kingdom. Neutropenia was defined as a neutrophil count of 2.0×10⁹/L or less, thrombocytopenia as a platelet count of 130×10⁹/L or less, and alanine aminotransferase (ALT) and alkaline phosphatase (ALP) levels were defined as increased if at 3 times the upper limit of normal.

Among patients in the low-dose (n=47) and high-dose (n=39) groups, the median age was 54.5 (IQR, 69.75-40.25) and 54.5 (IQR, 68.25-25.5) years, 44.7% and 35.9% were women, and the median duration of outpatient parenteral antimicrobial therapy (OPAT) was 19 (IQR, 14-33.75) and 20 (IQR, 12.75-34.25) days, respectively. Significant group differences in the rates of mono-MSSA or polymicrobial infections, bone and joint infections, intra-abdominal infections, gynecologic infections, and concomitant use of metronidazole were observed at baseline (all P £.023).

The researchers noted no significant differences between patients in the low- vs high-dose groups for rates of neutropenia (17.5% vs 15.4%; odds ratio [OR], 0.89; 95% CI, 0.26-2.63; P >.999), thrombocytopenia (0% vs 7.7%; P =.089), or increased ALT (10.6% vs 5.1%; P =.448) and ALP (2.1% vs 0%; P >.999) levels.

Rates of treatment discontinuation due to adverse effects also did not significantly differ between patients in the low- vs high-dose groups (4.3% vs 7.7%; OR, 1.86; 95% CI, 0.36-10.92; P =.655).

The results of this study may have been limited by the small sample size, as well as significant group differences in infection characteristics observed at baseline.

“We found no significant correlation between the incidence of neutropenia or thrombocytopenia and the dose of ceftriaxone,” the researchers concluded.

Disclosure: Multiple authors declared affiliations with industry. Please see the original reference for a full list of disclosures.

This article originally appeared on Infectious Disease Advisor