An Update on the arsenal for multidrug-resistant Acinetobacter infections: Polymyxin antibiotics

Objective: To review recent clinical pharmacokinetic and pharmacodynamic data to optimize dosing regimens for polymyxin B and colistin for treatment of infections due to A. baumannii. Methods: A literature search was performed using the search terms Acinetobacter, polymyxin, colistin, polymyxin B on MEDLINE. Additional references were identified from the resulting citations. Results: Increasing the dose of polymyxin B or colistin and using either in combination with other antibiotic agents demonstrates improved antimicrobial activity against Acinetobacter spp. Polymyxin B, unlike colistin, is available as an active drug and appears to be relatively unaffected by renal function. This is advantageous both for patients with renal impairment and for those with intact renal function. Achieving therapeutic serum concentrations of colistin may be difficult for those with intact renal function due to rapid clearance of the prodrug, colistimethate sodium (CMS). Clinical data are still lacking for polymyxin B, and it remains to be seen whether advantages demonstrated in PK/PD analyses will persist in the larger scale of patient care and safety. Conclusions: The use of higher doses of either colistin or polymyxin B, as well as combination with other antibiotics, may prevent emerging resistance and preserve the activity of polymyxins against A. baumannii

Radiology training in United Kingdom: current status.

Clinical radiology has always been one of the most competitive specialties in UK. Due to the increasing demand for radiology services the number of training posts in the UK has been increased. Clinical radiology training takes 5 years and requires completion of the Fellowship of Royal College of Radiologists (FRCR) exams, adequate evidence to demonstrate completion of the curriculum and successful appraisals. On completing training and receiving the Certificate for Completion of Training (CCT) a select proportion of trainees choose to embark on a fellowship program. This gives trainees the opportunity to further develop their subspecialty interest generating a high level of confidence in diagnostic and procedural skills

A comparative analysis of ECG-gated steady state free precession magnetic resonance imaging versus transthoracic echocardiography for evaluation of aortic root dimensions.

PURPOSE Accurate and reproducible measurement of aortic root dimensions is essential to inform clinical decision making. Transthoracic echocardiography (TTE) is the first line test for assessment of the aortic root but has potential limitations due to its limited field of view and restricted acoustic windows. Cardiac magnetic resonance imaging (MRI) is considered the "gold standard" technique for assessment of cardiac morphology and recently MRI reference ranges for aortic root dimensions have been published. The purpose of this study was to retrospectively compare aortic root measurements obtained from TTE with those derived from cardiac MRI. MATERIALS AND METHODS Sixty-eight patients (40 males, 28 females) who had undergone both cardiac MRI and TTE imaging within a 4-month interval (mean 62 days) were included. Steady-state-free precession MRI cine imaging was performed with an acquisition plane perpendicular to the aortic root and through the true cross sectional aortic valve plane. A cusp-commissure dimension from inside wall to inside wall in end-diastole was recorded and compared with standardized TTE derived Valsalva sinus measurements. Pearson correlation coefficients and a paired t-test were used for statistical analysis. RESULTS Mean aortic root dimension by TTE was 3.2±0.5 cm and MRI was 3.4±0.4 cm with a Pearson correlation coefficient of >0.7. Mean difference between TTE and MRI was 0.2±0.3 (P<0.001) with MRI producing a consistently higher measure. In four patients with a dilated aortic root by MRI the TTE measurement was within the normal reference range. In patients with a dilated aortic root (n=19) the mean difference was 0.2±0.4 cm (P<0.05) with MRI consistently producing the larger measure. In patients with a non-dilated aortic root t (n=49) the mean difference was 0.2±0.3 cm (P<0.05) with MRI consistently producing the larger measure. CONCLUSIONS There is a high level of correlation between TTE and MRI derived aortic root measurements at the Valsalva sinus level. MRI consistently measures the aortic root dimension higher than TTE which may under diagnose patients with a mildly dilated aortic root. Further investigation is required to properly integrate MRI into imaging assessment algorithms

Frequency of utilisation of ultrasound in the diagnosis of ectopic pregnancy in Sub-Saharan Africa countries: A systematic review

Introduction Ectopic pregnancy (EP) is a common diagnosis, frequently misdiagnosed early in its presentation and a leading cause of first trimester mortality. Ultrasound (US) is a key component of evidence-based diagnostic algorithms. We present a systematic review on the frequency of the use of US in the diagnosis of EP in Sub-Saharan Africa. Methods A librarian-assisted search of PUBMED, EMBASE, Cochrane, Web of Science, and POPLINE databases was performed. Inclusion criteria were original research studies that reported the proportion of patients receiving US as part of a workup for EP in a Sub-Saharan African country. Abstracts were reviewed and those potentially meeting criteria had a formal survey of the manuscript. Results The initial search revealed 784 original publications. Manual review of abstracts narrowed this to 91 papers with potential relevance, and 12 studies were included in the final analysis. A total of 6055 patients diagnosed with EP were included. 8.7% received a pregnancy test. 92.3% were ruptured at the time of presentation. 42.9% were in shock and 75.8% received red blood cell transfusion. 73.7% were unaware of the pregnancy and 24.9% were seen by a healthcare worker prior to presentation, 1.1% of patients died. Overall, 12.6% received US to aid in the diagnosis. Conclusion In this study, overall utilisation of US in the diagnosis of EP was found to be low. In this population, patients presented late and critically ill, obviating the need for US in many cases. However, studies in Sub-Saharan Africa in populations of patients with similar rates of late presentations have shown a substantial increase in the diagnosis of unruptured EP with the routine use of US

Safety of an i.v. β-adrenergic blockade protocol for heart rate optimization before coronary CT angiography.

OBJECTIVE The purpose of this study was to assess the safety of heart rate optimization by use of β-adrenergic blockade solely by the i.v. route before coronary CT angiography. MATERIALS AND METHODS The records of 679 patients undergoing CT coronary angiography after receiving i.v. β-adrenergic blockade were retrospectively analyzed. Health screening was completed before scanning, and heart rate was optimized by administration of i.v. metoprolol titrated to a maximum of 70 mg to achieve a heart rate less than 65 beats/min. RESULTS The median i.v. dose was 20 mg (range, 5-70 mg). The 679 patients analyzed had a total of 10 complications (1.47%). Major complications, defined as not resolving with observation and analgesia alone, occurred in only three patients (0.44%). These complications included a second-degree atrioventricular block. A total of 299 patients (44.0%) needed more than 20 mg of i.v. metoprolol to achieve target heart rate. Only three patients needed the maximum i.v. dose of 70 mg metoprolol. Target heart rate was reached successfully in 666 patients (98.1%) with doses of less than 70 mg. This study did not show a statistically significant association between increasing complication frequency and increasing dose. CONCLUSION This study showed that high doses of i.v. metoprolol can be used effectively and with a low rate of major complications to control heart rate before coronary CT angiography in correctly screened patients