New Predictive Equation for the Estimation of Plasma Concentrations of Formed Colistin in Patients Treated with Colistimethate Sodium for Multidrug-Resistant Gram-Negative Bacterial Infections.

BACKGROUND: The clinical use of colistin methanesulphonate (CMS) is limited by potential nephrotoxicity. The selection of an efficient and safe CMS dose for individual patients is complicated by the narrow therapeutic window and high interpatient pharmacokinetic variability. In this study, a simple predictive equation for estimating the plasma concentration of formed colistin in patients with multidrug and extremely drug-resistant gram-negative bacterial infections was developed. METHODS: The equation was derived from the largest clinical cohort of patients undergoing therapeutic drug monitoring (TDM) of colistin for over 8 years in a tertiary Spanish hospital. All variables associated with Css,avg were selected in a multiple linear regression model that was validated in a second cohort of 40 patients. Measured Css,avg values were compared with those predicted by our model and a previous published algorithm for critically ill patients. RESULTS: In total, 276 patients were enrolled [the mean age was 67.2 (13.7) years, 203 (73.6%)] were male, and the mean (SD) Css,avg was 1.12 (0.98) mg/L. Age, gender, estimated glomerular filtration rate, CMS dose and frequency, and concomitant drugs were included in the model. In the external validation, the previous algorithm appeared to yield more optimized colistin plasma concentrations when all types of Css,avg values (high and low) were considered, while our equation yielded a more optimized prediction in the subgroup of patients with low colistin plasma concentrations (Css,avg <1.5 mg/L). CONCLUSIONS: The proposed equation may help clinicians to better use CMS among a wide variety of patients, to maximize efficacy and prevent nephrotoxicity. A further prospective PK study is warranted to externally validate this algorithm.

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

BACKGROUND: Data 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. METHODS: A 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. RESULTS: One 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. CONCLUSIONS: When 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.

Clinical, economic, and humanistic impact of a multidisciplinary medication review with follow-up for anticoagulated patients treated with vitamin K antagonists in primary care: A cluster randomised controlled trial.

BACKGROUND: Interdisciplinary collaboration between general practitioner, nurses and pharmacists can favour the control of patients treated with vitamin K antagonists (VKA), increasing their safety and effectiveness. The aim of the study was to evaluate the impact of pharmaceutical interventions on patients treated with VKA within the framework of a Pharmacotherapeutic Follow-up service on clinical, economic and humanistic outcomes. METHODS: Controlled and randomized study in patients from two health areas of Zaragoza in treatment with VKA with Time in Therapeutic Range (TTR) according to the Rosendaal method less than 70% in the last 6 months. Patients were recruited at the pharmacy and assigned to two groups: control and intervention. A Pharmacotherapeutic Follow-up Program was established for the intervention group for 6 months. The outcome variables were INR stability, pharmacological adherence, vitamin K intake, knowledge about the use of acenocoumarol, quality of life, satisfaction with treatment, associated costs and avoided costs. A descriptive analysis was performed, and the Students' T test or Mann-Whitney U test was used for the association between quantitative variables and Chi-square or Fisher's test for qualitative variables. RESULTS: A total of 123 patients were included, 65 in the intervention group (IG) and 58 in the control group (CG). A total of 108 interventions were conducted (1.7 interventions/patient) and the most common were those related to the proper taking of medications (41.0%). In IG, TTR (p = 0.019), adherence to treatment (p = 0.038) and knowledge about acenocoumarol (p = 0.031) improved, compared to CG. A higher proportion of patients in IG achieved a TTR>65% (p = 0.024). In addition, patients whose interventions were accepted by the physician (p = 0.027) and those who received vitamin K optimization interventions (p = 0.003) achieved TTR>65% in greater proportion. CONCLUSIONS: Community pharmacist medication review, in collaboration with general practitioners improve knowledge and adherence of patients treated with oral anti-vitamin K agents and enhances the achievement of their therapeutic INR ranges. Investment needed to achieve this clinical impact is low and patient satisfaction is high. TRIAL REGISTRATION: This study has been registered with Clinical Trials.gov dated 25/05/2017: NCT03154489.

Importance of Pharmacogenetics and Drug-Drug Interactions in a Kidney Transplanted Patient.

Tacrolimus (TAC) is a narrow-therapeutic-range immunosuppressant drug used after organ transplantation. A therapeutic failure is possible if drug levels are not within the therapeutic range after the first year of treatment. Pharmacogenetic variants and drug-drug interactions (DDIs) are involved. We describe a patient case of a young man (16 years old) with a renal transplant receiving therapy including TAC, mycophenolic acid (MFA), prednisone and omeprazole for prophylaxis of gastric and duodenal ulceration. The patient showed great fluctuation in TAC blood concentration/oral dose ratio, as well as pharmacotherapy adverse effects (AEs) and frequent diarrhea episodes. Additionally, decreased kidney function was found. A pharmacotherapeutic follow-up, including pharmacogenetic analysis, was carried out. The selection of the genes studied was based on the previous literature (CYP3A5, CYP3A4, POR, ABCB1, PXR and CYP2C19). A drug interaction with omeprazole was reported and the nephrologist switched to rabeprazole. A lower TAC concentration/dose ratio was achieved, and the patient's condition improved. In addition, the TTT haplotype of ATP Binding Cassette Subfamily B member 1 (ABCB1) and Pregnane X Receptor (PXR) gene variants seemed to affect TAC pharmacotherapy in the studied patient and could explain the occurrence of long-term adverse effects post-transplantation. These findings suggest that polymorphic variants and co-treatments must be considered in order to achieve the effectiveness of the immunosuppressive therapy with TAC, especially when polymedicated patients are involved. Moreover, pharmacogenetics could influence the drug concentration at the cellular level, both in lymphocyte and in renal tissue, and should be explored in future studies.

[Low adherence to 2009 pandemic influenza A(H1N1) vaccination program among health care workers of a medical centre during the pandemic phase]. / Baja adhesión a un programa de vacunación contra la gripe A (H1N1) pandémica 2009 entre el personal sanitario de una institución durante la fase de pandemia.

INTRODUCTION: Several strategies have been designed to increase adherence to vaccination programs aimed at health professionals, though the results were not always satisfactory. MATERIAL AND METHODS: The differences between adherence to seasonal and pandemic influenza vaccination were assessed after the implementation of a vaccination program, and the predicting factors of adherence to the pandemic vaccine were identified. The adverse effects of this vaccine were analysed by means of a follow up e-questionnaire. RESULTS: The results revealed that 7.6% of professionals were vaccinated against pandemic influenza, and 33.7% against seasonal influenza. Statistically significant differences were observed for both vaccines when comparing vaccinated to unvaccinated professionals for age, professional category and workplace, while sex differences were only related to pandemic influenza. The highest rate of pandemic influenza vaccination was found among men older than 55 years old working as physicians in acute care hospitals. In the multivariate model, which showed a very good discriminatory power (Area under ROC curve=0.843), age, professional category, workplace and previous vaccination against seasonal influenza were independent predicting factors of vaccination against pandemic influenza. The main reason for vaccination was patient protection. The most frequent adverse effect was pain in the injection area. CONCLUSIONS: Adherence to pandemic influenza vaccination program was very low, which suggests the need to implement new strategies into vaccination programs. The main reason for vaccination was patient protection. The tolerability of the pandemic vaccine was good.

[Shedding light on the use of colistin: still gaps to be filled]. / 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.

Short Personality and Life Event scale for detection of suicide attempters.

OBJECTIVE: To develop a brief and reliable psychometric scale to identify individuals at risk for suicidal behaviour. DESIGN: Case-control study. SAMPLE AND SETTING: 182 individuals (61 suicide attempters, 57 psychiatric controls, and 64 psychiatrically healthy controls) aged 18 or older, admitted to the Emergency Department at Puerta de Hierro University Hospital in Madrid, Spain. MEASURES: All participants completed a form including their socio-demographic and clinical characteristics, and the Personality and Life Events scale (27 items). To assess Axis I diagnoses, all psychiatric patients (including suicide attempters) were administered the Mini International Neuropsychiatric Interview. STATISTICAL ANALYSIS: Descriptive statistics were computed for the socio-demographic factors. Additionally, χ(2) independence tests were applied to evaluate differences in socio-demographic and clinical variables, and the Personality and Life Events scale between groups. A stepwise linear regression with backward variable selection was conducted to build the Short Personality Life Event (S-PLE) scale. In order to evaluate the accuracy, a ROC analysis was conducted. The internal reliability was assessed using Cronbach's α, and the external reliability was evaluated using a test-retest procedure. RESULTS: The S-PLE scale, composed of just 6 items, showed good performance in discriminating between medical controls, psychiatric controls and suicide attempters in an independent sample. For instance, the S-PLE scale discriminated between past suicide and past non-suicide attempters with sensitivity of 80% and specificity of 75%. The area under the ROC curve was 88%. A factor analysis extracted only one factor, revealing a single dimension of the S-PLE scale. Furthermore, the S-PLE scale provides values of internal and external reliability between poor (test-retest: 0.55) and acceptable (Cronbach's α: 0.65) ranges. Administration time is about one minute. CONCLUSIONS: The S-PLE scale is a useful and accurate instrument for estimating the risk of suicidal behaviour in settings where the time is scarce.

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

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.

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 patient's 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.

Prospective comparison of severity scores for predicting mortality in community-acquired pneumonia.

INTRODUCTION: Specific prognostic models for community acquired pneumonia (CAP) to guide treatment decisions have been developed, such us the Pneumonia Severity Index (PSI) and the Confusion, Urea nitrogen, Respiratory rate, Blood pressure and age ≥ 65 years index (CURB-65). Additionally, general models are available such as the Mortality Probability Model (MPM-II). So far, which score performs better in CAP remains controversial. The objective was to compare PSI and CURB-65 and the general model, MPM-II, for predicting 30-day mortality in patients admitted with CAP. METHODS: Prospective observational study including all consecutive patients hospitalised with a confirmed diagnosis of CAP and treated according to the hospital guidelines. Comparison of the overall discriminatory power of the models was performed by calculating the area under a receiver operator characteristic curve (AUC ROC curve) and calibration through the Goodness-of-fit test. RESULTS: One hundred and fifty two patients were included (mean age 73.0 years; 69.1% male; 75.0% with more than one comorbid condition). Seventy-five percent of the patients were classified as high-risk subjects according to the PSI, versus 61.2% according to the CURB-65. The 30-day mortality rate was 11.8%. All three scores obtained acceptable and similar values of the AUCs of the ROC curve for predicting mortality. Despite all rules showed good calibration, this seemed to be better for CURB-65. CURB-65 also revealed the highest positive likelihood ratio. CONCLUSIONS: CURB-65 performs similar to PSI or MPMII for predicting 30-day mortality in patients with CAP. Consequently, this simple model can be regarded as a valid alternative to the more complex rules.

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

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.