Liver function, quantified by the LiMAx test, as a predictor for the clinical outcome of critically ill patients treated with linezolid

BACKGROUND

Critically ill patients commonly suffer from infections that require antimicrobial therapy. In previous studies, liver dysfunction was shown to have an essential impact on the dose selection in these patients. This pilot study aims to assess the influence of liver dysfunction, measured by the novel LiMAx test, on clinical outcomes in critically ill patients treated with linezolid.

METHODS

Twenty-nine critically ill patients were included and treated with linezolid. Indications for linezolid therapy were secondary or tertiary peritonitis (46.7%), bloodstream infection (6.7%) and 46.7% were other infections with gram-positive bacteria. Linezolid Cmin, maximal liver function capacity (LiMAx test) and plasma samples were collected while linezolid therapy was in a steady-state condition. Furthermore, potential factors for the clinical outcome were investigated using logistic regression analysis. Clinical cure was defined as the resolution or significant improvement of clinical symptoms without using additional antibiotic therapy or intervention.

RESULTS

Cured patients presented lower median linezolid Cmin yet a significantly higher mean LiMAx-value compared to the clinical failure group (1.9 mg/L vs. 5.1 mg/L) (349 μg/kg/h vs. 131 μg/kg/h). In the logistic regression model, LiMAx < 178 μg/kg/h was the only independent predictor of clinical failure with a sensitivity of 77% and specificity of 93%.

CONCLUSIONS

The LiMAx test predicts clinical failure more precisely than linezolid trough levels in critically ill surgical patients. Therefore liver failure may have a stronger impact on the outcome of critically ill surgical patients than low linezolid Cmin. While linezolid Cmin failed to predict patient's outcome, LiMAx results were the only independent predictor of clinical failure.

Tolerability of high-dose ceftriaxone in CNS infections: a prospective multicentre cohort study

BACKGROUND

Ceftriaxone is widely used to treat community-acquired CNS bacterial infections. French guidelines for meningitis in adults promote 75-100 mg/kg/day ceftriaxone without an upper limit for dosage, yet little is known about the pharmacology and tolerability of such regimens.

PATIENTS AND METHODS

A multicentre prospective cohort study was conducted in adult patients to assess the adverse drug reactions (ADRs) of high-dose ceftriaxone (i.e. daily dosage ≥4 g or ≥75 mg/kg) in CNS infections and to analyse their related factors. Drug causality was systematically assessed by an expert committee who reviewed the medical charts of all included patients.

RESULTS

A total of 196 patients were enrolled over a 31 month period. Median dosage and duration of ceftriaxone were 96.4 mg/kg/day (7 g/day) and 8 days, respectively. Nineteen ceftriaxone-related ADRs (mainly neurological) occurred in 17 patients (8.7%), with only one case of treatment discontinuation (biliary pseudolithiasis). In univariate analysis, older age, male gender, renal impairment and high trough ceftriaxone plasma concentration were associated with ceftriaxone-related ADRs.

CONCLUSIONS

High-dose ceftriaxone for CNS infection administered as recommended by French guidelines in adults was well tolerated overall, suggesting these recommendations could be applied and generalized. In patients with advanced age or renal insufficiency, prescription should be done with caution and therapeutic drug monitoring could be useful.

Antibiotic resistance of gram-negative bacilli isolated from pediatric patients with nosocomial bloodstream infections in a Mexican tertiary care hospital

BACKGROUND

Gram-negative bacilli are the most common bacteria causing nosocomial bloodstream infections (NBSIs) in Latin American countries.

METHODS

The antibiotic resistance profiles of Gram-negative bacilli isolated from blood cultures in pediatric patients with NBSIs over a 3-year period in a tertiary care pediatric hospital in Mexico City were determined using the VITEK-2 system. Sixteen antibiotics were tested to ascertain the resistance rate and the minimum inhibitory concentration using the Clinical Laboratory Standards Institute (CLSI) broth micro-dilution method as a reference.

RESULTS

A total of 931 isolates were recovered from 847 clinically significant episodes of NBSI. Of these, 477 (51.2%) were caused by Gram-negative bacilli. The most common Gram-negative bacilli found were Klebsiella pneumoniae (30.4%), Escherichia coli (18.9%), Enterobacter cloacae (15.1%), Pseudomonas aeruginosa (9.9%), and Acinetobacter baumannii (4.6%). More than 45 and 60% of the K. pneumoniae and E. coli isolates, respectively, were resistant to cephalosporins, and 64% of the E. coli isolates were resistant to fluoroquinolones. A. baumannii exhibited low rates of resistance to antibiotics tested. In the E. cloacae and P. aeruginosa isolates, no rates of resistance higher than 38% were observed.

CONCLUSIONS

In this study, we found that the proportion of NBSIs due to antibiotic-resistant organisms is increasing in a tertiary care pediatric hospital of Mexico.