Comparison of the probability of target attainment of anidulafungin against Candida spp. in patients with acute leukaemia

This study aimed to investigate the probability of target attainment (PTA) of various anidulafungin dosing regimens against Candida spp. in patients with acute leukaemia. A Monte Carlo simulation was performed using a previously published population pharmacokinetic model. The following dosing scenarios were evaluated: 200 mg loading dose (LD) on Day 1 then 100 mg daily (manufacturer's recommended dosing regimen); 200 mg LD on Day 1 then 100 mg every 48 h (q48 h); and 200 mg q48 h, 200 mg every 72 h (q72 h) and 300 mg q72 h. For each dosing regimen, free drug concentrations were calculated to evaluate the effect of 99% protein binding. The PTA at various pharmacodynamic (PD) targets was determined as the percentage of subjects who achieved a free drug area under the plasma concentration-time curve over the minimum inhibitory concentration ratio (ƒAUC/MIC) or a free drug maximum plasma concentration over the minimum inhibitory concentration ratio (ƒC(max)/MIC) above the PD targets. PTA expectation values were then calculated for each dosing regimen. The currently recommended dosing regimen of anidulafungin was not optimal for invasive candidiasis in patients with acute leukaemia. Alternate dosing strategies with higher doses and extended dosing intervals (intermittent dosing) achieved better target attainment. This is the first study to optimise therapy with anidulafungin using Monte Carlo simulation. These results provide a rationale in support of future clinical investigation of intermittent dosing of anidulafungin.

De novo membranous nephropathy in renal allograft associated with antibody-mediated rejection and review of the literature

A 71-year-old woman with unknown renal failure etiology received living donor transplantation had normal graft function for many years. At 11 years from transplantation, she developed nephrotic syndrome. Allograft biopsy showed membranous nephropathy (MN) and C4d positivity in the peritubular capillaries, suggestive of antibody-mediated rejection. At the time of nephrosis onset, she had new donor-specific antibody positivity. The case is unusual in that the diagnosis of de novo MN is based on evidence that she had antibody-mediated rejection. De novo MN remains relatively uncommon; we have reviewed the literature on this diagnosis.

Development and validation of a risk model for identification of non-neutropenic, critically ill adult patients at high risk of invasive Candida infection: the Fungal Infection Risk Evaluation (FIRE) Study

BACKGROUND

There is increasing evidence that invasive fungal disease (IFD) is more likely to occur in non-neutropenic patients in critical care units. A number of randomised controlled trials (RCTs) have evaluated antifungal prophylaxis in non-neutropenic, critically ill patients, demonstrating a reduction in the risk of proven IFD and suggesting a reduction in mortality. It is necessary to establish a method to identify and target antifungal prophylaxis at those patients at highest risk of IFD, who stand to benefit most from any antifungal prophylaxis strategy.

OBJECTIVES

To develop and validate risk models to identify non-neutropenic, critically ill adult patients at high risk of invasive Candida infection, who would benefit from antifungal prophylaxis, and to assess the cost-effectiveness of targeting antifungal prophylaxis to high-risk patients based on these models.

DESIGN

Systematic review, prospective data collection, statistical modelling, economic decision modelling and value of information analysis.

SETTING

Ninety-six UK adult general critical care units.

PARTICIPANTS

Consecutive admissions to participating critical care units.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Invasive fungal disease, defined as a blood culture or sample from a normally sterile site showing yeast/mould cells in a microbiological or histopathological report. For statistical and economic modelling, the primary outcome was invasive Candida infection, defined as IFD-positive for Candida species.

RESULTS

Systematic review: Thirteen articles exploring risk factors, risk models or clinical decision rules for IFD in critically ill adult patients were identified. Risk factors reported to be significantly associated with IFD were included in the final data set for the prospective data collection.

DATA COLLECTION

Data were collected on 60,778 admissions between July 2009 and March 2011. Overall, 383 patients (0.6%) were admitted with or developed IFD. The majority of IFD patients (94%) were positive for Candida species. The most common site of infection was blood (55%). The incidence of IFD identified in unit was 4.7 cases per 1000 admissions, and for unit-acquired IFD was 3.2 cases per 1000 admissions. Statistical modelling: Risk models were developed at admission to the critical care unit, 24 hours and the end of calendar day 3. The risk model at admission had fair discrimination (c-index 0.705). Discrimination improved at 24 hours (c-index 0.823) and this was maintained at the end of calendar day 3 (c-index 0.835). There was a drop in model performance in the validation sample. Economic decision model: Irrespective of risk threshold, incremental quality-adjusted life-years of prophylaxis strategies compared with current practice were positive but small compared with the incremental costs. Incremental net benefits of each prophylaxis strategy compared with current practice were all negative. Cost-effectiveness acceptability curves showed that current practice was the strategy most likely to be cost-effective. Across all parameters in the decision model, results indicated that the value of further research for the whole population of interest might be high relative to the research costs.

CONCLUSIONS

The results of the Fungal Infection Risk Evaluation (FIRE) Study, derived from a highly representative sample of adult general critical care units across the UK, indicated a low incidence of IFD among non-neutropenic, critically ill adult patients. IFD was associated with substantially higher mortality, more intensive organ support and longer length of stay. Risk modelling produced simple risk models that provided acceptable discrimination for identifying patients at 'high risk' of invasive Candida infection. Results of the economic model suggested that the current most cost-effective treatment strategy for prophylactic use of systemic antifungal agents among non-neutropenic, critically ill adult patients admitted to NHS adult general critical care units is a strategy of no risk assessment and no antifungal prophylaxis.

FUNDING

Funding for this study was provided by the Health Technology Assessment programme of the National Institute for Health Research.

Demographics of animal bite victims & management practices in a tertiary care institute in Mumbai, Maharashtra, India

BACKGROUND & OBJECTIVES

Rabies is an important public health problem worldwide and more than 55,000 people die annually of the disease. The King Edward Memorial Hospital, Mumbai, is a tertiary referral centre where a rabies clinic runs 24 hours. In view of lack of information about the demographics of the disease in an urban environment the present study was carried out.

METHODS

Data on 1000 consecutive animal bite victims presenting to the institute in 2010 were collected over a 15 wk period. An electronic database was specially created for capturing information and was modelled on the information available from the WHO expert consultation on rabies, 2005. Economic burden from the patients' perspective was calculated using both direct and indirect costs.

RESULTS

The victims were largely males (771 subjects). The dog was the major biting animal (891, 89.1%).Bites were mainly of Category III (783, 78.3%). One twenty three subjects used indigenous treatments only for local wound care. Of the Category III bites, only 21 of 783 (2.7%) patients were prescribed human rabies immunoglobulin (HRIG) which was primarily for severe bites or bites close to or on the face. A total of 318 patients did not complete the full Essen regime of the vaccine. The median cost to the patient per bite was Rs. 220 (3.5 USD).

INTERPRETATION & CONCLUSIONS

Our findings showed that the use of HRIG was low with less than 2 per cent of the Category III patients being prescribed it. As vaccine and HRIG continue to remain expensive, the intradermal vaccine, shorter regimes like the Zagreb regime and monoclonal antibodies may offer safer and cost-effective options in the future. Further studies need to be done in different parts of the country.

Functional and symptom impact of trametinib versus chemotherapy in BRAF V600E advanced or metastatic melanoma: quality-of-life analyses of the METRIC study

BACKGROUND

In a randomized phase III study, trametinib prolonged progression-free survival and improved overall survival versus chemotherapy in patients with BRAF V600 mutation-positive melanoma.

PATIENTS AND METHODS

Patients' quality of life (QOL) was assessed at baseline and follow-up visits using the European Organisation for Research and Treatment of Cancer Core QOL questionnaire.

RESULTS

In the primary efficacy population (BRAF V600E+, no brain metastases) from baseline to weeks 6 and 12, patients' global health status scores worsened by 4-5 points with chemotherapy but improved by 2-3 points with trametinib. Rapid and substantive reductions in QOL functionality (e.g. role functioning, 8-11 points at weeks 6 and 12) and symptom exacerbation (e.g. fatigue, 4-8 points; nausea and vomiting, 5 points, both at weeks 6 and 12) were observed in chemotherapy-treated patients. In contrast, trametinib-treated patients reported small improvements or slight worsening from baseline at week 12, depending on the functional dimension and symptom. The mean symptom-scale scores for chemotherapy-treated patients increased from baseline (symptoms worsened) for seven of eight symptoms at week 6 (except insomnia) and six of eight symptoms at week 12 (except dyspnea and insomnia). In contrast, at weeks 6 and 12, the mean symptom-scale scores for trametinib decreased from baseline (symptoms improved) for pain (11-12 points), insomnia (10-12 points), and appetite loss (1-5 points), whereas those for diarrhea worsened (15-16 points). Mixed-model repeated-measures analyses showed significant (P < 0.05) and/or clinically meaningful improvements (small to moderate) from baseline in favor of trametinib for global health; physical, role, and social functioning; fatigue; pain; insomnia; nausea and vomiting; constipation; dyspnea; and appetite at weeks 6 and/or 12. QOL results for the intent-to-treat population were consistent.

CONCLUSIONS

This first QOL assessment for a MEK inhibitor in metastatic melanoma demonstrated that trametinib was associated with less functional impairment, smaller declines in health status, and less exacerbation of symptoms versus chemotherapy.

The prevalence of iron deficiency anaemia in patients undergoing bariatric surgery

As bariatric surgery rates continue to climb, anaemia will become an increasing concern. We assessed the prevalence of anaemia and length of hospital stay in patients undergoing bariatric surgery. Prospective data (anaemia [haemoglobin <12 g/dL], haematinics and length of hospital stay) was analysed on 400 hundred patients undergoing elective laparoscopic bariatric surgery. Results from a prospective database of 1530 patients undergoing elective general surgery were used as a baseline. Fifty-seven patients (14%) were anaemic pre-operatively, of which 98% were females. Median MCV (fL) and overall median ferritin (μg/L) was lower in anaemic patients (83 vs. 86, p=0.001) and (28 vs. 61, p<0.0001) respectively. In the elective general surgery patients, prevalence of anaemia was similar (14% vs. 16%) but absolute iron deficiency was more common in those undergoing bariatric surgery; microcytosis p<0.0001, ferritin <30 p<0.0001. Mean length of stay (days) was increased in the anaemic compared to in the non-anaemic group (2.7 vs. 1.9) and patients who were anaemic immediately post-operatively, also had an increased length of stay (2.7 vs. 1.9), p<0.05. Absolute iron deficiency was more common in patients undergoing bariatric surgery. In bariatric patients with anaemia there was an overall increased length of hospital stay.