The cost-effectiveness of ESBL detection: towards molecular detection methods?

Correct detection of extended-spectrum beta-lactamases (ESBLs) is crucial for infection control and antibiotic choice. We performed a study to determine the cost-effectiveness of phenotypical testing, which can be inaccurate, and genotypical tests, which are considered to be more reliable but also more expensive. All patients that had been in isolation in the Amphia hospital because of the detection of ESBL according to the ESBL Etest were included in the survey. All strains were retested using the double disk confirmation test (DDCT) and a genotypical method. This was a commercially available microarray (Check-Points). Discordant results were confirmed by PCR and sequencing. In total 174 patients were included. In 24 of 174 (14%) patients, ESBL carriage could not be confirmed with the microarray. This was verified with PCR and sequencing. The mean duration of isolation was 15 days, adding up to a total number of isolation days of 2571. False-positive results according to the microarray resulted in a total of 279 days of unnecessary isolation for the Etest and 151 days for the DDCT. Using Etest to detect the presence of ESBL results in a false-positive outcome in 14% of the cases. This results in unnecessary isolation of patients, which can be omitted by using a genotypic method.     

Early detection of idiopathic scoliosis – analysis of three screening models

Introduction

The prevalence of lateral curvatures of the spine ranges from 0.3% to 15.3% in the general population. The aim of the study was to develop and compare three different screening tests for idiopathic scoliosis (IS) with respect to their effectiveness and costs.

Material and methods

The Delphi method was used to assess the efficacy of each screening algorithm in detecting IS in the population. An economic analysis was also performed.

Results

Diagnostic Algorithm 1 for IS comprised a screening examination performed by nurses and a general practitioner (GP) with verification by specialists. The unit cost of carrying out diagnostic work-up for IS in Algorithm 1 was €94 per child. The second algorithm involved the use of the moiré computer method, followed by verification by a specialist. The lower unit cost of €86 per child of diagnostic work-up according to Algorithm 2 was due to fewer stages compared to Algorithm 1. The highest effectiveness with the highest costs were found for the third algorithm, with only one stage, a specialist''s consultation (cost €153 per child).

Conclusions

The number of stages in an algorithm does not correlate positively with its efficacy or cost. The recommended scheme is Algorithm 3, where children are examined by rehabilitation specialists or a physiotherapist using a scoliometer and an inclinometer. The use of the apparently most expensive scheme (Algorithm 3) should result in lowering the costs of treatment of established idiopathic scoliosis and, in the long term, prove to be the most cost-effective solution for the health care system.     

Fabrication of oligonucleotide microarray for the detection of Japanese encephalitis virus

A low-density oligonucleotide microarray was used for the detection of Japanese encephalitis virus (JEV) , combining with restriction display PCR labeling method. The hybridization targets were amplified from 6 plasmids containing several JEV gene fragments. Corresponding oligonucleotide probe spots were detected unambiguously. We claim that the oligonucleotide microarray technology is feasible and may have potential for clinical laboratory application.     

Comparison of BACTEC™ blood culture media for the detection of fungemia

The aim of the present study was to investigate whether addition of the BACTEC? Mycosis bottle to the standard BACTEC? aerobic and anaerobic bottles contributed to a higher detection rate and a faster time to detection (TTD) of fungi. This was a retrospective cohort study of all patients with a positive blood culture with Candida species delivered to the Department of Clinical Microbiology, Herlev and Gentofte Hospital, Denmark in the 8-year period 2006 through 2014. The patients had at least one BACTEC? aerobic and one Mycosis bottle sampled at the same time and at least one of the bottles yielded growth of fungi. Among 184 patients included, 173 were examined using BACTEC? aerobic, anaerobic and Mycosis bottles. The anaerobic vial generally had the lowest detection rate and the longest TTD. The detection rate of BACTEC? aerobic plus anaerobic with the BACTEC? Mycosis bottle was significantly higher than the detection rate of BACTEC? aerobic plus anaerobic without BACTEC? Mycosis bottle for all species after 1–5 days, and specially for Candida glabrata at 2, 3, 4 and 5 days. TTD for C. glabrata was significantly shorter for BACTEC? Mycosis than TTD for BACTEC? aerobic or anaerobic bottles after ½ to 4 days. When combining “first or only” detection, the BACTEC? Mycosis bottle had a significantly higher detection as compared to the aerobic bottle. Addition of the BACTEC? Mycosis bottle to the standard BACTEC? aerobic and anaerobic bottles significantly contributed to a higher detection rate and a faster TTD of fungemia.     

Identifying and enhancing risk thresholds in the detection of elder financial abuse: a signal detection analysis of professionals’ decision making

Background

Financial abuse of elders is an under acknowledged problem and professionals’ judgements contribute to both the prevalence of abuse and the ability to prevent and intervene. In the absence of a definitive “gold standard” for the judgement, it is desirable to try and bring novice professionals’ judgemental risk thresholds to the level of competent professionals as quickly and effectively as possible. This study aimed to test if a training intervention was able to bring novices’ risk thresholds for financial abuse in line with expert opinion.

Methods

A signal detection analysis, within a randomised controlled trial of an educational intervention, was undertaken to examine the effect on the ability of novices to efficiently detect financial abuse. Novices (n?=?154) and experts (n?=?33) judged “certainty of risk” across 43 scenarios; whether a scenario constituted a case of financial abuse or not was a function of expert opinion.Novices (n?=?154) were randomised to receive either an on-line educational intervention to improve financial abuse detection (n?=?78) or a control group (no on-line educational intervention, n?=?76). Both groups examined 28 scenarios of abuse (11 “signal” scenarios of risk and 17 “noise” scenarios of no risk). After the intervention group had received the on-line training, both groups then examined 15 further scenarios (5 “signal” and 10 “noise” scenarios).

Results

Experts were more certain than the novices, pre (Mean 70.61 vs. 58.04) and post intervention (Mean 70.84 vs. 63.04); and more consistent. The intervention group (mean 64.64) were more certain of abuse post-intervention than the control group (mean 61.41, p = 0.02). Signal detection analysis of sensitivity (A´) and bias (C) revealed that this was due to the intervention shifting the novices’ tendency towards saying “at risk” (C post intervention -.34) and away from their pre intervention levels of bias (C-.12). Receiver operating curves revealed more efficient judgments in the intervention group.

Conclusion

An educational intervention can improve judgements of financial abuse amongst novice professionals.

     

Is detection of schizocytes by computerised image analysis accurate?

Schistocytes result from red cell fragmentation. The identification of the schistocytes is critical for decisions on appropriate management of the patients. Currently, a systematic approach to the counting method remains rewarded. We programmed a computer image analysis device (Q-Win, Leica) in order to detect fragmented red cells. A good correlation between the computer and a well-trained biologist was found after minor modifications of the computer's results. Image analysis should reduced the biologist-to-biologist variation and improve the identification and enumeration of the schistocytes.     

Performance evaluation of EuDx™ ufPCR Flu & RSV detection kit for detection of influenza A/B and respiratory syncytial virus

EuDx? ufPCR Flu & RSV Detection Kit (EUDIPIA, Chungcheongbuk-do, Republic of Korea) is a recently developed molecular assay for simultaneously detecting influenza A/B and respiratory syncytial virus (RSV). We evaluated this assay in a clinical setting and demonstrated its excellent performance for diagnosing influenza A/B and RSV infections.     

Comparison of isoelectric focusing and polymerase chain reaction for the detection of β-lactamases

Extended spectrum β-lactamases (ESBLs) have been observed in virtually all the species of family Enterobacteriaceae. Threat posed by antibiotic resistance because of ESBLs is more serious as a number of technical problems are associated with the detection of these enzymes. Although a number of detection methods have been designed for ESBLs, every method has its own benefits and shortcomings as well. In earlier days, isoelectric focusing (IEF) was used as the gold standard for ESBL detection. This study was undertaken to compare IEF with polymerase chain reaction, a method which has been extensively used for ESBL detection these days.     

Evaluation of the Oxoid Brilliance™ CRE Agar for the detection of carbapenemase-producing Enterobacteriaceae

The adequate detection of carbapenemase-producing Enterobacteriaceae (CPE) is essential for adequate antibiotic therapy and for infection control purposes, especially in an outbreak setting. Selective agars play an important role in the detection of CPE. The Oxoid Brilliance? CRE Agar (Thermo Fisher Scientific) was evaluated for the detection of CPE using 255 non-repetitive Enterobacteriaceae isolates, including 95 CPE (36 KPC, 4 KPC plus VIM, 4 NDM, 6 GIM, 20 VIM, and 25 OXA-48-producing isolates). The sensitivity of the CRE agar for the detection of CPE was 94 % (89/95), but differed per carbapenemase gene (100 % for KPC, NDM, and GIM, 90 % for VIM, and 84 % for OXA-48-producing isolates). The specificity of the CRE agar was 71 %, due to the growth of AmpC- and/or ESBL-producing isolates. The CRE agar is a sensitive tool for the detection of KPC and metallo-carbapenemase-producing Enterobacteriaceae, although the detection of OXA-48 producers is less optimal. The relatively low specificity requires confirmation of carbapenemase production for isolates recovered from the CRE agar.     

Is tinnitus useful in early detection of incoming heart decompensation?

In previous studies the possibility of a mechanism of hemodynamic imbalance consequent to a sharp decrease in blood pressure causing a more or less transient inner ear impairment was evaluated and to some extent demonstrated. In this scenario, tinnitus is very frequently present as a debilitating symptom associated to cochlear impairment. On the other hand, a possible cause of a sharp decrease in blood pressure is represented by major cardiovascular disorders, requiring an early assessment in order to avoid fatal consequences. In this paper, the hypothesis of resorting to tinnitus as a simple warning method for self detecting a possibly incoming cardiovascular imbalance in patients with heart failure (HF) is advanced.     

Total internal reflection photoacoustic spectroscopy for the detection of β-hematin

Evanescent field sensing methods are currently used to detect many different types of disease markers and biologically important chemicals such as the HER2 breast cancer receptor. Hinoue et al. used Total Internal Reflection Photoacoustic Spectroscopy (TIRPAS) as a method of using the evanescent field to detect an optically opaque dye at a sample interface. Although their methods were successful at detecting dyes, the results at that time did not show a very practical spectroscopic technique, which was due to the less than typical sensitivity of TIRPAS as a spectroscopy modality given the low power (≈ 1 to 2 W) lasers being used. Contrarily, we have used an Nd:YAG laser with a five nanosecond pulse that gives peak power of 1 MW coupled with the TIRPAS system to increase the sensitivity of this technique for biological material sensing. All efforts were focused on the eventual detection of the optically absorbing material, hemozoin, which is created as a byproduct of a malarial infection in blood. We used an optically analogous material, β-hematin, to determine the potential for detection in the TIRPAS system. In addition, four properties which control the sensitivity were investigated to increase understanding about the sensor's function as a biosensing method.     

Multimodality approach to optical early detection and mapping of oral neoplasia

Early detection of cancer remains the best way to ensure patient survival and quality of life. Squamous cell carcinoma is usually preceded by dysplasia presenting as white, red, or mixed red and white epithelial lesions on the oral mucosa (leukoplakia, erythroplakia). Dysplastic lesions in the form of erythroplakia can carry a risk for malignant conversion of 90%. A noninvasive diagnostic modality would enable monitoring of these lesions at regular intervals and detection of treatment needs at a very early, relatively harmless stage. The specific aim of this work was to test a multimodality approach [three-dimensional optical coherence tomography (OCT) and polarimetry] to noninvasive diagnosis of oral premalignancy and malignancy using the hamster cheek pouch model (nine hamsters). The results were compared to tissue histopathology. During carcinogenesis, epithelial down grow, eventual loss of basement membrane integrity, and subepithelial invasion were clearly visible with OCT. Polarimetry techniques identified a four to five times increased retardance in sites with squamous cell carcinoma, and two to three times greater retardance in dysplastic sites than in normal tissues. These techniques were particularly useful for mapping areas of field cancerization with multiple lesions, as well as lesion margins.     

A field evaluation of formalin–gasoline technique in the concentration of stool for detection of intestinal parasites

A field evaluation of the formalin–gasoline procedure to detect parasite ova, cysts, or larvae from 470 fecal specimens (comprising both fresh and formalin-preserved stool samples) was compared with that of the formalin–ether sedimentation technique. Parallel concentrates with diethyl ether and gasoline were prepared for each specimen, and the species and appearance of recovered parasite species were determined. Of 470 total specimens, 206 (43.83%) were found to be positive for parasites in one or both concentration techniques. Gasoline was comparable to diethyl ether in the recovery of parasite eggs, cysts, and larvae, so that the formalin–gasoline and the formalin–diethyl ether sedimentation techniques detected 165 and 156 positive of total specimens, respectively. In this study, gasoline proved to be as good as diethyl ether in concentrating parasite eggs and cysts, as well as in maintaining characteristic morphology. However, gasoline was considerably superior to diethyl ether in detecting larvae of Strongyloides stercoralis. Parallel examination of total stool samples by the routine formalin–ether (original) and by the formalin–gasoline techniques resulted in identical distribution of positive slides and morphology of recovered parasite species. However, the easy availability of gasoline (wherever gas stations are present) and its low cost in comparison to ether makes gasoline superior to ether for use in concentration of stools by the sedimentation method in laboratories, including laboratories with limited material resources and also laboratories present in small cities and rural health centers.     

Can the MiniSCID improve the detection of bipolarity in private practice?

BACKGROUND: Several recent studies have re-examined the prevalence of Bipolar Disorder, raising the suspicion that it is being underdiagnosed, particularly early in the course of the disease. The MiniSCID is a screening instrument for Axis-I diagnoses. METHOD: A chart review was performed on all 1161 active patients seen in an outpatient setting. Data collected included demographic information, initial clinical diagnosis, current clinical diagnosis, MiniSCID diagnoses, and SCL-90 results. RESULTS: Of the 796 patients who had taken the MiniSCID at their initial visit, 256 have a current clinical diagnosis of Bipolar Disorder, and 540 have a nonbipolar diagnosis. They were seen over an average period of 5.3 years. The MiniSCID had a sensitivity of 0.58 and a specificity of 0.63 in predicting a current diagnosis of bipolar disorder. There are 201 patients who endorsed current or past mania/hypomania on the MiniSCID, yet have a current clinical diagnosis of a nonbipolar illness. These patients had a SCL-90 profile that was much closer to those of bipolar patients than those of unipolar patients. LIMITATIONS: The major limitation is the reliability and validity of the MiniSCID. CONCLUSIONS: There is a large group of patients who are potentially bipolar, but are not yet clinically diagnosed as such. Several factors relating to this finding are discussed. The use of MiniSCID and SCL-90 as an in-office-screening tool can improve recognition of Bipolar illness.     

Kullback–Leibler divergence for detection of rare haplotype common disease association

Rare haplotypes may tag rare causal variants of common diseases; hence, detection of such rare haplotypes may also contribute to our understanding of complex disease etiology. Because rare haplotypes frequently result from common single-nucleotide polymorphisms (SNPs), focusing on rare haplotypes is much more economical compared with using rare single-nucleotide variants (SNVs) from sequencing, as SNPs are available and ‘free'' from already amassed genome-wide studies. Further, associated haplotypes may shed light on the underlying disease causal mechanism, a feat unmatched by SNV-based collapsing methods. In recent years, data mining approaches have been adapted to detect rare haplotype association. However, as they rely on an assumed underlying disease model and require the specification of a null haplotype, results can be erroneous if such assumptions are violated. In this paper, we present a haplotype association method based on Kullback–Leibler divergence (hapKL) for case–control samples. The idea is to compare haplotype frequencies for the cases versus the controls by computing symmetrical divergence measures. An important property of such measures is that both the frequencies and logarithms of the frequencies contribute in parallel, thus balancing the contributions from rare and common, and accommodating both deleterious and protective, haplotypes. A simulation study under various scenarios shows that hapKL has well-controlled type I error rates and good power compared with existing data mining methods. Application of hapKL to age-related macular degeneration (AMD) shows a strong association of the complement factor H (CFH) gene with AMD, identifying several individual rare haplotypes with strong signals.     

First detection of VIM-4 metallo-β-lactamase-producing Escherichia coli in Russia

An Escherichia coli isolate co-producing VIM-4 metallo-β-lactamase and CTX-M-15 extended spectrum β-lactamase was recovered from the urine of a patient with head trauma in Moscow, Russia. The bla_VIM-4and bla_CTX-M-15genes were carried, respectively, by transmissible plasmids of IncW and Inc 11 groups. The nucleotide sequence of the VIM-4-encoding integron was nearly identical to that of In4/6, which represent a large group of structurally related integrons previously found in Enterobacteriaceae all around the Mediterranean basin. This is the first report of a metallo-β-lactamase-producing E. coliin Russia.