Isothermal microcalorimetry minimal inhibitory concentration testing in extensively drug resistant Gram-negative bacilli: a multicentre study

OBJECTIVES

To evaluate the performance of an isothermal microcalorimetry (IMC) method for determining the MICs among extensively drug-resistant Gram-negative bacilli.

METHODS

A collection of 320 clinical isolates (n = 80 of each) of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Acinetobacter baumannii from Sweden, Spain, Italy and the Netherlands were tested. The MICs were determined using the IMC device calScreener (Symcel, Stockholm, Sweden) and ISO-broth microdilution as the reference method. Essential agreement, categorical agreement, very major errors (VME), major errors (ME) and minor (mE) errors for each antibiotic were determined.

RESULTS

Data from 316 isolates were evaluated. Four errors (two ME, one VME, one mE) among 80 K. pneumoniae, six errors (four ME, one VME, one mE) among 79 E. coli, 15 errors (seven VME, three ME, five mE) among 77 P. aeruginosa and 18 errors (12 VME, two ME, four mE) among 80 A. baumannii were observed. Average essential agreement and categorical agreement of the IMC method were 96.6% (95% confidence interval, 94.2-99) and 97.1% (95% confidence interval, 95.4-98.5) respectively when the MICs were determined at the end of 18 hours. Categorical agreement of the IMC method for prediction of MIC by the end of 8 hours for colistin, meropenem, amikacin, ciprofloxacin and piperacillin/tazobactam were 95%, 91.4%, 94%, 95.2% and 93.7% respectively.

CONCLUSIONS

The IMC method could accurately determine the MICs among extensively drug-resistant clinical isolates of E. coli, K. pneumoniae, P. aeruginosa and A. baumannii isolates.

Dissemination of the multidrug-resistant extended-spectrum β-lactamase-producing Escherichia coli O25b-ST131 clone and the role of house crow (Corvus splendens) foraging on hospital waste in Bangladesh

Two hundred and thirty-eight faecal samples from crows foraging on hospital wastes were analysed for extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. ESBL-producing crow isolates were characterized and compared with 31 patient isolates. Among the crows, 59% carried ESBL producers. These included Escherichia coli, Klebsiella pneumoniae, Raoultella terrigena and Enterobacter cloacae harbouring the genes for CTX-M-1, CTX-M-15, CTX-M-55, CTX-M-79, and CTX-M-14. Human isolates carried only the CTX-M-15 gene. Two-thirds of crow E. coli isolates and all human E. coli isolates were multidrug resistant. Crows and patients shared E. coli sequence types, including the epidemic E. coli O25b-ST131 clone. The scavenging behaviour of crows at poorly managed hospital waste dumps made them potential reservoirs of antibiotic resistance, including ESBLs.

New clinical research strategies in thoracic oncology: clinical trial design, adaptive, basket and umbrella trials, new end-points and new evaluations of response

In the genomics era, our main goal should be to identify large and meaningful differences in small, molecularly selected groups of patients. Classical phase I, II and III models for drug development require large resources, limiting the number of experimental agents that can be tested and making the evaluation of targeted agents inefficient.

There is an urgent need to streamline the development of new compounds, with the aim of identifying “trials designed to learn”, which could lead to subsequent “trials designed to conclude”.

Basket trials are often viewed as parallel phase II trials within the same entity, designed on the basis of a common denominator, which can be a molecular alteration(s). Most basket trials are histology-independent and aberration-specific clinical trials. Umbrella trials are built on a centrally performed molecular portrait and molecularly selected cohorts with matched drugs, and can include patients’ randomisation and strategy validation. Beyond new designs, new end-points and new evaluation techniques are also warranted to finally achieve methodology and clinical improvements, in particular within immunotherapy trials.

Trimodality therapy for malignant pleural mesothelioma: results from an EORTC phase II multicentre trial

The European Organisation for Research and Treatment of Cancer (EORTC; protocol 08031) phase II trial investigated the feasibility of trimodality therapy consisting of induction chemotherapy followed by extrapleural pneumonectomy and post-operative radiotherapy in patients with malignant pleural mesothelioma (with a severity of cT3N1M0 or less). Induction chemotherapy consisted of three courses of cisplatin 75 mg·m⁻² and pemetrexed 500 mg·m⁻². Nonprogressing patients underwent extrapleural pneumonectomy followed by post-operative radiotherapy (54 Gy, 30 fractions). Our primary end-point was "success of treatment" and our secondary end-points were toxicity, and overall and progression-free survival. 59 patients were registered, one of whom was ineligible. Subjects' median age was 57 yrs. The subjects' TNM scores were as follows: cT1, T2 and T3, 36, 16 and six patients, respectively; cN0 and N1, 57 and one patient, respectively. 55 (93%) patients received three cycles of chemotherapy with only mild toxicity. 46 (79%) patients received surgery and 42 (74%) had extrapleural pneumonectomy with a 90-day mortality of 6.5%. Post-operative radiotherapy was completed in 37 (65%) patients. Grade 3-4 toxicity persisted after 90 days in three (5.3%) patients. Median overall survival time was 18.4 months (95% CI 15.6-32.9) and median progression-free survival was 13.9 months (95% CI 10.9-17.2). Only 24 (42%) patients met the definition of success (one-sided 90% CI 0.36-1.00). Although feasible, trimodality therapy in patients with mesothelioma was not completed within the strictly defined timelines of this protocol and adjustments are necessary.

Phase II feasibility trial of induction chemotherapy (ICT) followed by extrapleural pneumonectomy (EPP) and postoperative radiotherapy (PORT) for cT3N1M0 or less malignant pleural mesothelioma (MPM) (EORTC 08031)

7509

Background: MPM is a highly lethal disease and the role of EPP in the treatment of early stage, potentially resectable MPM remains controversial. EORTC 08031 phase II trial investigated the feasibility of trimodality therapy (TMT) consisting of ICT followed by EPP and PORT. Methods: Eligibility criteria were cT3N1M0 or less, proven MPM, < 70 years, PS 0–1, fit for TMT. ICT consisted of 3 courses of cisplatin 75mg/m2 and pemetrexed 500mg/m2 q3weeks. Non-progressing patients (pts) underwent EPP followed by PORT (54Gy, 30 fractions). Primary endpoint was “success of treatment” defined as a patient receiving the full protocol treatment, still alive 90 days after end of treatment without progression and without grade (G) 3–4 toxicity. Using a one step Fleming design 52 patients and 26 successes were required. Secondary endpoints were toxicity of TMT, overall and progression-free survival. Results: 59 pts were registered between 07/26/05 and 08/24/07, 1 was ineligible. Median age was 57 years (range 26–67), M/F 46/12, all proven MPM (31 epithelial, 18 mixed, 9 other). All pts underwent mediastinoscopy, cT1/T2/T3: 36/16/6, cN0/N1: 57/1. 55 pts received 3 cycles of ICT. G3–4 toxicity related to ICT was rare. 46 pts (79%) were operated, 42 (74%) had EPP. R0/1/2: 30/10/3, 6 were re-operated, pT0/1/2/3/4: 2/5/19/15/4, pN0/1/2/3: 34/2/6/2, 90-day mortality: 3 pts (6.5%); in 38 pts (83%) postoperative complications occurred. PORT was initiated in 38 pts and completed in 37 (65%). After PORT 2 pts (3.5%) died due to infection. Persisting G3/4 toxicity after 90 days: 3 pts (5.3%) due to radiation pneumonitis and bronchopleural fistula. After median follow- up of 19.3 months (mos) median overall survival time was 18.4 mos (95% CI 14.8-NR) and median progression-free survival was 13.9 mos (95% CI 10.9–17.1). Only 24 pts (42%) met the definition of success (one-sided 90% CI 0.36–1.00). Conclusions: EORTC 08031 investigated the feasibility of TMT in pts with proven MPM. Due to the low proportion of “successes” this TMT is not considered to be feasible. Although overall results were similar to other series, adjustments to this TMT are necessary.

No significant financial relationships to disclose.

Adjuvant chemotherapy in elderly patients: An analysis of National Cancer Institute of Canada Clinical Trials Group and Intergroup BR.10

7009

Background: Recent trials have shown significant survival benefit from adjuvant chemotherapy after resection of NSCLC. Whether elderly patients tolerate platinum-based adjuvant chemotherapy and derive the same survival advantage is unknown. This retrospective study evaluated the influence of age on survival, chemotherapy delivery and toxicity in NCIC CTG BR.10. Methods: Pretreatment characteristics and survival benefit from treatment were compared for patients ≤65 & >65. Chemotherapy delivery and toxicity were compared for 213 treated patients. Results: There were 327 young and 155 elderly patients. Baseline prognostic factors by age were similar with the exception of histology (adeno 58% young, 43% elderly; squamous 32% young, 49% elderly; p=0.001) and PS (PS 0 53% young, 41% elderly; p=0.01). Overall survival by age showed a trend favoring the young in univariate (HR 0.77, CI 0.58–1.04, p=0.084) and multivariate analyses (HR 0.75, CI 0.56–1.01, p=0.059). Patients >75 years had significantly shorter survival than those aged 66–74 (HR 1.95, CI 1.11–3.41, p=0.02). Overall survival for patients >65 was significantly better with chemotherapy v observation (HR 0.61, CI 0.38–0.98, p=0.04). Chemotherapy administration and toxicity were evaluated in 63 elderly and 150 young patients. Mean dose intensities of vinorelbine (V) and cisplatin (C) were 13.2 and 18.0 in the young and 9.9 and 14.1 in the elderly (V p=0.0004; C p=0.001). The elderly received significantly fewer doses of V (p=0.014) and C (p=0.006). Fewer elderly patients completed treatment and more refused treatment compared to the young (p=0.03). There were no significant differences in toxicities, G-CSF use or hospitalization by age group, except for myalgias and mood alteration (more frequent among the young). Six of 126 deaths (4.8%) in the young were from non-malignant causes v 12 of 71 (16.9%) in the elderly (p=0.008). Conclusions: In spite of receiving less chemotherapy than young patients, adjuvant chemotherapy improves overall survival in patients aged >65 with acceptable toxicity. Adjuvant chemotherapy should not be withheld from elderly patients, although patients >75 years of age require further study.

No significant financial relationships to disclose.

Identifying patients with non-small cell lung cancer (NSCLC) unlikely to benefit from erlotinib: An exploratory analysis of National Cancer of Institute of Canada Clinical Trials Group BR.21

7161

Background: Despite a 9% response rate, BR.21 demonstrated significant survival benefit for patients receiving erlotinib as 2nd/3rd line therapy for NSCLC. We undertook to characterize, by exploratory subset analysis, patients less likely to benefit from erlotinib. To identify factors for consideration, we first identified baseline characteristics associated with early progression by eight wks and early death by 3 mos. Methods: Using stratification factors and potential prognostic factors from BR.21, the Cox regression model with stepwise selection was used to establish a prognostic model to separate erlotinib patients into 4 risk categories based on the 10th, 50th & 90th percentiles of prognostic index scores. 7 variables (smoking history, PS, weight loss, anemia, high LDH, response to prior chemo and time from diagnosis to randomization) were used in the final model. The hypothesis was that the characteristics of the treated patients in the highest risk group would also be predictive of lack of benefit from erlotinib when erlotinib and placebo patients with the same characteristics were compared. Results: Factors associated with PD by 8 wks were: PS2–3 (p = 0.009), weight loss (p = 0.0004), anemia (p = 0.008), PD to prior chemo (p = 0.006), non-Asian (p = 0.047), EGFR IHC-negative (p = 0.005), Factors associated with survival < 3 mos were: PS2–3 (p < 0.0001), weight loss (p < 0.0001), anemia (p < 0.0001), PD to prior chemo (p < 0.0001), non-Asian (p = 0.008), high LDH (p < 0.0001), time to randomization <12 mos (p = 0.0003). Comparison of overall survival for the 4 risk groups derived from prognostic index score as follows: high benefit (HR = 0.41, p = 0.007), 2 intermediate benefit (HR 0.79, p = 0.09; HR 0.80; p = 0.09); no benefit (HR 1.23; p = 0.42). Median survivals for erlotinib (placebo) patients in each group were 17.3 (8.3), 9.7 (7.5), 4.1 (3.7), 1.9 (2.7) mos. Conclusions: By establishing a prognostic model, we identified a small group of patients who are unlikely to benefit from 2nd/3rd line erlotinib therapy. This model requires prospective validation to confirm that it is both prognostic and predictive of outcome from treatment.

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Febrile seizures: factors affecting risk of recurrence in Pakistani children presenting at the Aga Khan University Hospital

OBJECTIVES

To (a) describe the effect of temperature rise on seizure recurrence in the ER (b) investigate the effect of age, gender, family and developmental history, type, duration and multiple seizures, past history and number of seizures and treatment given (either late or early) on seizure recurrence in the ER and (c) explore prognostic indicators for seizure recurrence.

METHODS

Data from 352 children [ages 3-84 months; 220 males (62.5%) 132 females (37.5%)] was taken using chart reviews for the years January 1998-August 2000 inclusive, from the Pediatric department of the Aga Khan University Hospital. Descriptive statistics, Chi-square, and Discriminant Analysis were used.

RESULTS

Of the 52 (16%) cases that had seizure recurrence in the ER, majority (36.5%) occurred in > 38.5 degrees < or = 39.5 degrees C temperature range. The percentage declined to 15% at higher temperatures. Bivariate tests showed that age, family and developmental history, type of seizure and treatment given did not affect seizure recurrence in the ER. Past history number of seizures (p = .006), duration of seizure (p < 0.001), past history of seizures (p = 0.004) and multiple seizure (p = 0.024) were factors significantly associated with seizure recurrence in the ER at the bivariate level of analysis. Duration of seizure was the most important prognostic indicator for FS recurrence in the ER at the multivariate level with beta = .79.

CONCLUSION

Duration of seizure (> 5 minutes) was the most important prognostic factor for FS recurrence. Early treatment did not affect recurrence,suggesting timely anti-pyretic vs. anti-leptic medication use.

Rupture of the uterus in labor: a review of 150 cases

We analyzed 150 cases of uterine rupture in late pregnancy that occurred over an 8-year period at the State Maternity Hospital in Ankara, Turkey. The incidence of uterine rupture was 1 in 966 deliveries, and 114 uterine ruptures occurred in previously scarred uteri. Rupture of the unscarred uterus is a more catastrophic event. There is a marked difference in fetal and maternal outcome between the group with a previously scarred uterus and the group without a previous scar. Common etiological factors for uterine rupture were grandmultiparity, cephalopelvic disproportion, fetal malpresentation, and oxytocin stimulation of labor. The fetal wastage was high, a perinatal mortality of 32.2% being recorded, but 98% of mothers were saved. Hysterectomy was commonly performed in this group. Repair of the uterus should only be performed when the rupture is simple, is in the lower segment and has no sign of infection.