A Retrospective Study to Compare the Incidence of Hyponatremia after Administration between Linezolid and Tedizolid

Linezolid (LZD) and Tedizolid (TZD) are oxazolidinone antibiotic for meticillin-resistant Staphylococcus aureus (MRSA). Severe hyponatremia after LZD administration have been reported. Severe hyponatremia cause seizures, unconsciousness, and even death. Therefore, we conducted a study to assess the change of serum sodium level after LZD and TZD therapy. We enrolled 67 patients treated with LZD and 28 treated with TZD. We monitored the serum sodium level from the administration to 14 days after administration of oxazolidinone drug. Hyponatremia was defined a sodiuln level ≤134 mmol/L after the initiation of oxazolidinone drug. The frequency of hyponatremia in the LZD group was significantly higher than that in the TZD group (39.7% vs. 11.1%, p < 0.05). The rate of patients administered by injection was significantly higher than in the LZD group than in the TZD group (52.9% vs. 14.8%, p < 0.01). Multiple logistic regression analyses identified the albumin level before the oxazolidinone drug therapy as the independent variables associated with the development of hyponatremia. We revealed that TZD is safer than LZD in terms of hyponatremia. Therefore, cases that LZD is administered by injection should be used more carefully with hyponatremia in patients with low albumin level.

Safety of linezolid, rifampicin, and clindamycin combination therapy in patients with prosthetic joint infection

We investigated adverse events in patients with prosthetic joint infections receiving combination therapy with linezolid, rifampicin, and clindamycin for ≥ 7 days. Twenty-two patients were evaluated. The combination therapy was administered for 15.5 (7-29) days at dosages of 1200, 450, and 450-1200 mg/day for linezolid, rifampicin, and clindamycin, respectively. Adverse events (gastrointestinal, eye, and skin disorders; liver damage; myelosuppression; hyponatremia, and others) were recorded. The incidence rates of leukopenia, neutropenia, anemia, thrombocytopenia, and hyponatremia were 36.4%, 31.8%, 40.9%, 18.2%, and 18.2%, respectively. Common Terminology Criteria for Adverse Events version 5.0 Grade 3 neutropenia, anemia, and hyponatremia were observed. The incidence rate of myelosuppression was higher following combination therapy compared with that previously reported following single-drug administration. All patients were discharged after the infection was under control. It is important to monitor these adverse events during combination therapy with the aforementioned agents; these conditions may be relieved by discontinuing linezolid.

Investigation of the risk factors of vomiting during linezolid therapy: a retrospective observational study

PURPOSE

Some clinical studies have reported the occurrence of nausea and vomiting with linezolid (LZD) administration. However, no studies have evaluated nausea and vomiting as primary endpoints. In a previous study, we noted a possible relationship between LZD and vomiting, but risk factors were not identified. Therefore, the aim of the present study was to identify them.

METHODS

Patients who received LZD 600 mg twice daily at Hokkaido University Hospital from September 2008 to April 2019 were enrolled in this retrospective observational study. Patient characteristics, concomitant medications, laboratory data, and the occurrence of vomiting were obtained from electronic medical records. Logistic regression analysis was performed to identify risk factors for vomiting, including age, sex, body weight, concomitant medications, and surgeries.

RESULTS

A total of 496 patients were included in this study, of which 90 experienced vomiting. By multivariate logistic regression analysis, female sex (adjusted odds ratio [aOR], 2.69; 95% confidence interval [CI], 1.62-4.47), ≥ 10 days of LZD administration (aOR, 2.57; CI, 1.46-4.50), and hyponatraemia (aOR, 2.96; CI, 1.72-5.10) were identified as independent risk factors for vomiting; administration of serotonergic agents (aOR, 0.23; CI, 0.07-0.82) was negatively associated.

CONCLUSIONS

This study is the first to successfully identify risk factors for LZD-induced vomiting. Careful monitoring of patients with these risk factors may lead to safer and sustainable LZD administration.

A retrospective test for a possible relationship between linezolid-induced thrombocytopenia and hyponatraemia

WHAT IS KNOWN AND OBJECTIVE

Thrombocytopenia is one of the typical adverse events caused by linezolid (LZD). Recently, some cases of severe hyponatraemia occurring while receiving LZD have been reported. This study investigated a possible relationship between LZD-induced hyponatraemia and thrombocytopenia and identified the risk factors for hyponatraemia and/or thrombocytopenia.

METHODS

In this retrospective, single-centre, observational cohort study, 63 hospitalized patients aged over 18 years who received intravenous injection of LZD for more than seven consecutive days in Oita University Hospital between April 2015 and March 2018 were analysed.

RESULTS

Thrombocytopenia occurred in 25 (39.7%) patients and hyponatraemia in 11 (17.5%) patients. Seven of 11 patients with hyponatraemia had concurrent thrombocytopenia. Although both serum sodium level and platelet count declined in most patients who developed hyponatraemia, no significant association between thrombocytopenia and hyponatraemia was found. Creatinine clearance level (Ccr) was significantly lower not only in the thrombocytopenia (vs no-thrombocytopenia) but also in the hyponatraemia group (vs no-hyponatraemia group). Univariate and multivariate logistic regression analyses identified different risk factors for thrombocytopenia and/or hyponatraemia (thrombocytopenia: Ccr and administration period; hyponatraemia: serum albumin; thrombocytopenia and hyponatraemia: administration period and serum albumin).

WHAT IS NEW AND CONCLUSION

In conclusion, this study found no significant relationship between LZD-induced thrombocytopenia and hyponatraemia and identified some possible risk factors associated with onset of the two adverse events. These require further validation.

Evaluation of the relationship between linezolid exposure and hyponatremia

INTRODUCTION

Aims of this study were (a) to assess the development ratio of hyponatremia during treatment with linezolid and (b) to evaluate the relationship between the risk of hyponatremia and linezolid exposure and patient background.

METHOD

Clinical data including linezolid serum concentrations and serum sodium values were collected at Toyama University Hospital and Kyorin University Hospital. Data from 89 patients were used for the analysis, and a nadir serum sodium level ≤130 mmol/L during the treatment with linezolid was defined as hyponatremia. Mann-Whitney's U test was used to evaluate the effects of the area under the time-concentration curve (AUC) of linezolid at the nadir sodium level, clinical characteristics (e.g. laboratory data), and baseline serum sodium levels on the development of hyponatremia.

RESULTS

The hyponatremia was occurred in 21 of 89 patients (23.6%). Data are compared for baseline and nadir serum sodium levels of patients with and without hyponatremia. In both groups, nadir serum sodium levels were significantly different from those of the baseline values (P < 0.05). The values of AUC_0-12, accumulated AUC, baseline serum sodium levels and age were significantly different between patients with and without hyponatremia (P < 0.05).

CONCLUSIONS

Linezolid exposure, age, and baseline sodium levels were detected as the risk factors for linezolid-related hyponatremia. Our findings suggest that regular monitoring of serum sodium levels is desirable during treatment with linezolid, especially for the elderly and patients with low serum sodium levels before the start of linezolid administration.

[Verification of Relationship between Administration of Linezolid and Vomiting]

Linezolid (LZD), an antimicrobial agent against methicillin-resistant Staphylococcus aureus, demonstrates good bone and joint penetration, and is used for prosthetic bone and joint infections. Recently, we observed vomiting in several patients administered LZD. However, there are few reports on the incidence rate of, and risk factors for, LZD-induced nausea and vomiting. In this study, we aimed to verify the relationship between LZD administration and vomiting. Patients administered LZD at the Department of Orthopedic Surgery of Hokkaido University Hospital between November 2008 and December 2017 were enrolled in the study. The primary endpoint was the comparison of the vomiting rate between patients administered LZD (LZD group) and those administered other antibiotics (non-LZD group). For the secondary endpoint, to verify the risk factors of vomiting, a univariate logistic regression analysis was performed. In total, 130 patients were included in this study; 77 patients in the LZD group, and 53 in the non-LZD group. Vomiting occurred in 18 patients in the LZD group and 4 patients in the non-LZD group (23.4% and 7.5%, respectively); this was significantly higher in the LZD group. In the univariate logistic regression analysis, LZD administration, gender (female), age ≥65 years, renal impairment (creatinine clearance <60 mL/min) and concomitant use of rifampicin were extracted as potential risk factors of vomiting. The results of this study reveal a possible relationship between LZD administration and vomiting.