Nuria Berenguer

Trough colistin plasma level is an independent risk factor for nephrotoxicity: a prospective observational cohort study

BackgroundData regarding the most efficacious and least toxic schedules for the use of colistin are scarce. The aim of this study was to determine the incidence and the potential risk factors of colistin-associated nephrotoxicity including colistin plasma levels.MethodsA prospective observational cohort study was conducted for over one year in patients receiving intravenous colistin methanesulfonate sodium (CMS). Blood samples for colistin plasma levels were collected immediately before (Cmin) and 30 minutes after CMS infusion (Cmax). Renal function was assessed at baseline, on day 7 and at the end of treatment (EOT). Severity of acute kidney injury (AKI) was defined by the RIFLE (risk, injury, failure, loss, and end-stage kidney disease) criteria.ResultsOne hundred and two patients met the inclusion criteria. AKI related to CMS treatment on day 7 and at the end of treatment (EOT) was observed in 26 (25.5%) and 50 (49.0%) patients, respectively. At day 7, Cmin (OR, 4.63 [2.33-9.20]; P < 0.001) was the only independent predictor of AKI. At EOT, the Charlson score (OR 1.26 [1.01-1.57]; P = 0.036), Cmin (OR 2.14 [1.33-3.42]; P = 0.002), and concomitant treatment with ≥ 2 nephrotoxic drugs (OR 2.61 [1.0-6.8]; P = 0.049) were independent risk factors for AKI. When Cmin was evaluated as a categorical variable, the breakpoints that better predicted AKI were 3.33 mg/L (P < 0.001) on day 7 and 2.42 mg/L (P < 0.001) at EOT.ConclusionsWhen using the RIFLE criteria, colistin-related nephrotoxicity is observed in a high percentage of patients. Cmin levels are predictive of AKI. Patients who receive intravenous colistin should be closely monitored and Cmin might be a new useful tool to predict AKI.

Effective removal of colistin methanesulphonate and formed colistin during intermittent haemodialysis in a patient infected by polymyxin-only-susceptible Pseudomonas aeruginosa

Abstract Colistin use has reemerged for the treatment of infections caused by multidrug-resistant Gram-negative bacteria. However, the information on its pharmacokinetics is limited, especially in patients with end-stage renal disease, in which dosage adjustments are contradictory, and evidences the need to investigate the removal of colistin through renal replacement therapies like haemodialysis. This case study showed efficient removal of colistin methanesulphonate and formed colistin during intermittent haemodialysis in a patient infected by polymyxin-only-susceptible Pseudomonas aeruginosa. These results suggest the importance to monitor colistin plasma concentrations in these patients to minimize treatment failure due to suboptimal exposure to antibacterial colistin.

Luces y sombras en el uso de colistina: falta mucho por conocer

Colistin (polymyxin E), an old antibiotic replaced by other less toxic antibiotics in the 1970s, has been increasingly used over the last decade due to multidrug-resistance in Gram-negative bacteria and lack of new antibiotics. However, there is a dearth of information on the pharmacokinetics (PK), pharmacodynamics (PD) and toxicodynamics (TD) of colistin and its non-active prodrug colistimethate sodium (CMS). Optimised dose regimens have not been established for different types of patients. Additionally, most PK data available in the literature were obtained from concentrations derived from potentially misleading microbiological assays. Therefore, it is urgent to conduct prospective studies to optimise CMS/colistin use in patients, in particular the critically ill. This review summarises recent key clinical studies evaluating the efficacy, toxicity and PK/PD of colistin/CMS.

Pacientes con riesgo de desnutrición: valoración de 11 casos gravemente desnutridos con nutrición parenteral total individualizada

Objective: To describe and assess the efficacy and safety of individualised nutritional support during the first week of total parenteral nutrition in moderately to severely malnutritioned patients who are susceptible to the refeeding syndrome. Method: Retrospective observational study carried out between January 2003 and June 2006, including adult patients with moderate to severe malnutrition who received ≥ 5 days total parenteral nutrition. The nutritional support was described and the appearance of severe hydroelectrolytic and metabolic disturbances were assessed during the first week of nutrition. Results: The study included 11 patients with a mean body mass index of 15.4 kg/m2. These patients received an average of 23 Kcal/kg/day. They did not show any signs of severe hydroelectrolytic or metabolic disturbances. Three patients presented with hypophosphataemia, five with hypokalaemia and four with hypomagnesaemia, all of which were mild to moderate and with the exception of two cases, all were corrected within one week of feeding. Conclusions: Individualised nutritional support in moderately to severely malnourished patients does not produce refeeding syndrome. Individualised nutrition is an essential strategy for avoiding complications associated with overfeeding.

RevisiónLuces y sombras en el uso de colistina: falta mucho por conocerShedding light on the use of colistin: still gaps to be filled

Colistin (polymyxin E), an old antibiotic replaced by other less toxic antibiotics in the 1970s, has been increasingly used over the last decade due to multidrug-resistance in Gram-negative bacteria and lack of new antibiotics. However, there is a dearth of information on the pharmacokinetics (PK), pharmacodynamics (PD) and toxicodynamics (TD) of colistin and its non-active prodrug colistimethate sodium (CMS). Optimised dose regimens have not been established for different types of patients. Additionally, most PK data available in the literature were obtained from concentrations derived from potentially misleading microbiological assays. Therefore, it is urgent to conduct prospective studies to optimise CMS/colistin use in patients, in particular the critically ill. This review summarises recent key clinical studies evaluating the efficacy, toxicity and PK/PD of colistin/CMS.

Long-term treatment with linezolid in a patient with osteomyelitis undergoing hemodialysis.

Abstract Anemia and/or thrombocytopenia are the most relevant adverse effects of linezolid treatment. We report the case of a patient under hemodialysis who developed osteomyelitis involving the amputation stump of the left limb due to a vancomycin-resistant and teicoplanin-resistant Enterococcus faecium successfully treated with linezolid for 6 months. Close monitorization of the patient probably contributed to maintenance of treatment with linezolid despite hematological alterations observed, which could be attributed to either the underlying patient’s clinical condition or antimicrobial treatment.

Factors associated with adherence to guidelines for the use of tigecycline in a tertiary care hospital.

Abstract We assessed the adherence to the prescribing hospital protocol for tigecycline and factors associated with noncompliance. A total of 103 patients were included in the study. In 23 (22.3%) patients, tigecycline was not administered according to the protocol, mostly because of the availability of other therapeutic alternatives and prescription for indications that were not included in the guidelines. Factors independently associated with nonadherence to the protocol were community-acquired infection (OR, 14.01; 95% CI, 1.54-127.12; P=0.019), and empirical tigecycline treatment (OR, 6.97; 95% Ci, 0.88- 55.40; P=0.066). Penicillin allergy (OR, 0.004; 95% CI, 0.000-0.071; P=0.001) and previous antibiotic treatment (OR, 0.025; 95% CI, 0.003-0.233; P=0.001) were factors associated with adherence to the hospital protocol. A positive time trend between total number of prescriptions and non-compliant prescriptions with the protocol was observed (Spearmans rho coefficient 0.971; P=0.001). Adherence to tigecycline protocol could be improved by focusing on protocols for community-acquired infections, mainly skin and soft tissue infections.

Normalization of creatine kinase values in a case of rhabdomyolysis during daptomycin treatment.

A 41-year-old woman presented in the Emergency Department with suspected compartment syndrome of lower left leg (creatine kinase [CK]: 12,502 IU/L, Cr: 4.31 mg/dL). Fasciotomy of the four limb compartments was conducted. By day 2, the patient presented oliguria during previous 24 h, so daily intermittent dialysis was carried out. On day 12, the patient presented an episode of bacteremia due to Staphylococcus hominis. Treatment with vancomycin was initiated and was changed after 4 days to daptomycin due to unsatisfactory clinical progression (6 mg/kg every 48 h, according to renal function and patients weight) (CK: 2,972 IU/L). After 15 days of treatment, the dose of daptomycin was increased to 6 mg/kg every 24 h (CrCL: 46 mL/min, CK: 83 IU/L). The antibiotic was continued for another 4 days. Fourteen days later, the patient was discharged (CK: 26 IU/L). Daptomycin could be prescribed in some patients with elevated CK values. A cut-off value of baseline CK for use of daptomycin needs to be determined.