Intravenous colistin in the treatment of multidrug-resistant gram-negative organism in tertiary hospital, Jazan, KSA

Background

It was considered that the resistance of drugs such as carbapenems and cephalosporins against severe or high risk gram-negative bacteria became a tremendous confront. This might be attributed to the little amount of these drugs to be used against the multi-resistant bacteria (MRB). Therefore, Colistin, Fosfomycin, Temocillin, and Rifampicin are antibiotics that have been used as multidrug-resistant bacterial infections in the treatment of some species of bacteria such as Acinetobacter, Pseudomonas species, and Enterobacteriaceae.

Aim

the present study is aimed to assess the integrity and efficiency of colistin for treating of the multidrug-resistant bacteria (MDR) especially gram-negative one among critical and non-critical patients in tertiary hospital in Jazan city. Ninety four patients who met the selection criteria and received colistimethate sodium (colistin) in the period between Februarys 2017 and March 2018 were recruited and their charts were reviewed retrospectively. Patients' information, medical conditions, and laboratory data were extracted. All patients received IV colistin, and the majority of the patients showed in their culture reports multidrug-resistant bacteria such as Pseudomonas aeruginosa and Acinetobacter baumannii. Patients who had normal renal function received from 2.5 to 5.0 mg of colistin/kg, which was divided in two or three doses intravenously, for duration ranging between 10 and 14 days.

Results and conclusion

Approximately half of patients (48.93%) were fully recovered, while 19% of them were partially responded to colistin treatment. In the current study it was showed that IV colistin treatment against the multidrug-resistant bacteria (gram-negative bacteria) was strongly related to mild nephrotoxicity in addition to with a proper response as shown only in three of our patients.

Updated US and European Dose Recommendations for Intravenous Colistin: How Do They Perform?

BACKGROUND

The US Food and Drug Administration (FDA) and European Medicines Agency (EMA) have approved updated dose recommendations for intravenous colistin in patients with various degrees of renal function. We assessed the recommendations in relation to their ability to achieve clinically relevant plasma colistin concentrations.

METHODS

Pharmacokinetic data from 162 adult critically ill patients (creatinine clearance range, 5.4-211 mL/min) were used to determine the average steady-state plasma colistin concentration (Css,avg) that would be achieved if each patient received the FDA or EMA dose. Target attainment rates for FDA- and EMA-approved daily doses to achieve colistin Css,avg of ≥0.5, ≥1, ≥2, and ≥4 mg/L were determined for each creatinine clearance category (≥80 mL/min, 50 to <80 mL/min, 30 to <50 mL/min, and <30 mL/min).

RESULTS

For creatinine clearance <30 mL/min, 100% of patients receiving the EMA dose achieved a colistin Css,avg ≥1 mg/L, but the attainment rate was as low as 53.1% for patients receiving the FDA-approved dose. For colistin Css,avg ≥2 mg/L, the attainment rates were 87.5% with the EMA dose but only 6.3%-34.4% in patients receiving the FDA dose. Differences in attainment rates for a colistin Css,avg of ≥2 mg/L and ≥4 mg/L extended to patients with creatinine clearance 30 to <50 mL/min. For patients with creatinine clearance ≥80 mL/min, only approximately 65%-75% of patients achieved a colistin Css,avg of ≥1 mg/L with either set of recommendations.

CONCLUSIONS

The study highlights important differences between the FDA- and EMA-approved dose recommendations and informs the setting of clinical breakpoints.

CLINICAL TRIALS REGISTRATION

NCT00235690.