Evaluation of the novel DiaSorin LIAISON®Campylobacter assay for the rapid detection of Campylobacter spp.

Introduction

Campylobacter spp. infection is one of the leading causes of foodborne diarrhoeal illness in humans worldwide. The purpose of this study was to evaluate the DiaSorin LIAISON^®Campylobacter assay for human campylobacteriosis diagnosis.

Evaluation of a commercial enzyme‐linked immunosorbent assay for detection of antibodies against the H5 subtype of Influenza A virus in waterfowl

The ID Screen Influenza H5 Antibody Competition enzyme‐linked immunosorbent assay was tested for the detection of antibodies to the H5 subtype of influenza A (IA) virus in waterfowl. Assays were conducted with sera obtained from Mallards (Anas platyrhynchos) and Pekin Ducks (Anas platyrhynchos domestica), experimentally infected with eight low pathogenic (LP) and nine highly pathogenic (HP) H5N1 IA viral strains. Three incubation periods (1, 4 and 18 hours) and two dilutions (1:2 and 1:5) were tested. All serum samples from LP H5‐infected birds tested positive; however, improved detection rates were observed for viruses belonging to the HP H5N1 clade 2.2.1 as compared with those belonging to clade 2.1.3.     

Evaluation of MALDI-TOF mass spectrometry and Sepsityper Kit? for the direct identification of organisms from sterile body fluids in a Canadian pediatric hospital

Matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) can be used to identify bacteria directly from positive blood and sterile fluid cultures. The authors evaluated a commercially available kit – the Sepsityper Kit (Bruker Daltonik, Germany) – and MALDI-TOF MS for the rapid identification of organisms from 80 flagged positive blood culture broths, of which 73 (91.2%) were blood culture specimens and seven (8.7%) were cerebrospinal fluid specimens, in comparison with conventional identification methods. Correct identification to the genus and species levels was obtained in 75 of 80 (93.8%) and 39 of 50 (78%) blood culture broths, respectively. Applying the blood culture analysis module, a newly developed software tool, improved the species identification of Gram-negative organisms from 94.7% to 100% and of Gram-positive organisms from 66.7% to 70%.MALDI-TOF MS is a promising tool for the direct identification of organisms cultured from sterile sites.     

Who Needs Inpatient Detox? Development and Implementation of a Hospitalist Protocol for the Evaluation of Patients for Alcohol Detoxification

BACKGROUND

Clinicians caring for patients seeking alcohol detoxification face many challenges, including lack of evidence-based guidelines for treatment and high recidivism rates.

OBJECTIVES

To develop a standardized protocol for determining which alcohol dependent patients seeking detoxification need inpatient versus outpatient treatment, and to study the protocol’s implementation.

DESIGN

Review of best evidence by ad hoc task force and subsequent creation of standardized protocol. Prospective observational evaluation of initial protocol implementation.

PARTICIPANTS

Patients presenting for alcohol detoxification.

INTERVENTION

Development and implementation of a protocol for evaluation and treatment of patients requesting alcohol detoxification.

MAIN MEASURES

Number of admissions per month with primary alcohol related diagnosis (DRG), 30-day readmission rate, and length of stay, all measured before and after protocol implementation.

RESULTS

We identified one randomized clinical trial and three cohort studies to inform the choice of inpatient versus outpatient detoxification, along with one prior protocol in this population, and combined that data with clinical experience to create an institutional protocol. After implementation, the average number of alcohol related admissions was 15.9 per month, compared with 18.9 per month before implementation (p?=?0.037). There was no difference in readmission rate or length of stay.

CONCLUSIONS

Creation and utilization of a protocol led to standardization of care for patients requesting detoxification from alcohol. Initial evaluation of protocol implementation showed a decrease in number of admissions.     

Evaluation of MRSASelect? chromogenic medium for the early detection of methicillin-resistant Staphylococcus aureus from blood cultures

INTRODUCTION:

Staphylococcus aureus bacteremia is associated with considerable morbidity and mortality. In theory, reducing the turnaround time in reporting of methicillin-resistant S aureus (MRSA) among patients with bactermia could assist with the rapid optimization of antimicrobial therapy.

OBJECTIVE:

To evaluate the sensitivity and specificity of MRSASelect (Bio-Rad Laboratories, USA), a chromogenic medium, in the early detection of MRSA from blood cultures growing Gram-positive cocci in clusters, and to confirm that routine use of this medium would, in fact, reduce turnaround time for MRSA identification.

METHODS:

The present study was conducted at three microbiology laboratories in Manitoba. Between April 2010 and May 2011, positive blood cultures with Gram-positive cocci in clusters visualized on Gram stain were subcultured to both MRSASelect and routine media. MRSA isolates were identified using conventional microbiological methods from routine media and using growth with the typical colony morphology (pink colony) on MRSASelect medium.

RESULTS:

A total of 490 blood cultures demonstrating Gram-positive cocci in clusters on Gram stain were evaluated. S aureus was recovered from 274 blood cultures, with 51 S aureus isolates (51 of 274 [18.6%]) identified as MRSA. MRSASelect medium had a sensitivity of 98%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 99.8% for the recovery and identification of MRSA directly from positive blood culture bottles. In addition, use of MRSASelect medium was found to improve turnaround time in the detection of MRSA by almost 24 h relative to conventional methods.

DISCUSSION:

These data support the utility of MRSASelect medium for the rapid identification of MRSA from positive blood cultures. Further clinical studies are warranted to determine whether the improvement in turnaround time will result in a measurable reduction in suboptimal antimicrobial therapy and/or improvement in patient outcome.     

Development of a fluorescence immunochromatographic assay for the detection of zeta globin in the blood of (--(SEA)) α-thalassemia carriers

Southeast Asian deletion (--(SEA)) α-thalassemia is an inherited monogenic disorder of human hemoglobin, and embryonic globin ζ (hemoglobin ζ, zeta globin chain or Hb zeta chain) has been shown to be a marker that can be used for the identification of carriers of the (--(SEA)) α-thalassemia deletion. In this work, a fluorescence immunochromatographic assay (FL-ICA) was established to detect the zeta globin chain in the hemolysates of carriers of the (--(SEA)) α-thalassemia deletion. This assay can be completed within 10min using a simple UV detector and does not suffer from interference from the red background color of the hemolysate. A total of 314 blood samples were tested by FL-ICA and ELISA. The results of these assays were confirmed by PCR, the standard technique for genetic disease testing. The sensitivity and specificity of this novel FL-ICA were 100% and 98.0%, respectively; the corresponding values for the ELISA performed simultaneously were 100% and 99.2%, respectively. In conclusion, a new FL-ICA-a simple, fast, convenient, low-cost method-was developed that may be useful in both high-throughput screening and individual detection of the (--(SEA)) α-thalassemia deletion in carriers. Additionally, this qualitative FL-ICA may enlighten the development of a new systems for analysis of other target molecules using whole-blood samples.     

What are the most effective strategies for improving quality and safety of health care?

There is now a plethora of different quality improvement strategies (QIS) for optimizing health care, some clinician/patient driven, others manager/policy‐maker driven. Which of these are most effective remains unclear despite expressed concerns about potential for QIS‐related patient harm and wasting of resources. The objective of this study was to review published literature assessing the relative effectiveness of different QIS. Data sources comprising PubMed Clinical Queries, Cochrane Library and its Effective Practice and Organization of Care database, and HealthStar were searched for studies of QIS between January 1985 and February 2008 using search terms based on an a priori QIS classification suggested by experts. Systematic reviews of controlled trials were selected in determining effect sizes for specific QIS, which were compared as a narrative meta‐review. Clinician/patient driven QIS were associated with stronger evidence of efficacy and larger effect sizes than manager/policy‐maker driven QIS. The most effective strategies (>10% absolute increase in appropriate care or equivalent measure) included clinician‐directed audit and feedback cycles, clinical decision support systems, specialty outreach programmes, chronic disease management programmes, continuing professional education based on interactive small‐group case discussions, and patient‐mediated clinician reminders. Pay‐for‐performance schemes directed to clinician groups and organizational process redesign were modestly effective. Other manager/policy‐maker driven QIS including continuous quality improvement programmes, risk and safety management systems, public scorecards and performance reports, external accreditation, and clinical governance arrangements have not been adequately evaluated with regard to effectiveness. QIS are heterogeneous and methodological flaws in much of the evaluative literature limit validity and generalizability of results. Based on current best available evidence, clinician/patient driven QIS appear to be more effective than manager/policy‐maker driven QIS although the latter have, in many instances, attracted insufficient robust evaluations to accurately determine their comparative effectiveness.     

Assessment of the multiplex PCR-based assay Unyvero pneumonia application for detection of bacterial pathogens and antibiotic resistance genes in children and neonates

Background

Pneumonia is a major healthcare problem. Rapid pathogen identification is critical, but often delayed due to the duration of culturing. Early, broad antibacterial therapy might lead to false-negative culture findings and eventually to the development of antibiotic resistances. We aimed to assess the accuracy of the new application Unyvero P50 based on multiplex PCR to detect bacterial pathogens in respiratory specimens from children and neonates.

Methods

In this prospective study, bronchoalveolar lavage fluids, tracheal aspirates, or pleural fluids from neonates and children were analyzed by both traditional culture methods and Unyvero multiplex PCR.

Results

We analyzed specimens from 79 patients with a median age of 1.8 (range 0.01–20.1). Overall, Unyvero yielded a sensitivity of 73.1% and a specificity of 97.9% compared to culture methods. Best results were observed for non-fermenting bacteria, for which sensitivity of Unyvero was 90% and specificity 97.3%, while rates were lower for Gram-positive bacteria (46.2 and 93.9%, respectively). For resistance genes, we observed a concordance with antibiogram of 75% for those specimens in which there was a cultural correlate.

Conclusions

Unyvero is a fast and easy-to-use tool that might provide additional information for clinical decision making, especially in neonates and in the setting of nosocomial pneumonia. Sensitivity of the PCR for Gram-positive bacteria and important resistance genes must be improved before this application can be widely recommended.

     

Can elastometry be used for a better identification of cirrhosis?

Increased stiffness has been directly associated to fibrosis. Stage 4 fibrosis defines cirrhosis. Can elastometry (transient elastography, acoustic radiation force impulse imaging) be used for a better identification of cirrhosis? The answer is obviously yes, provided hepatologists, radiologists, pathologists, and biologists combine their expertise because severe chronic liver disease is a complex subject. Considering the pathogenesis of cirrhosis, it is likely that factors such as parenchymal extinction (leading to atrophy of the liver mass with approximation of portal tracts and hepatic veins) and exudation (congestion) play a role in liver stiffness not mentioning heart failure, liver necrosis and extrahepatic cholestasis. Neglecting these factors, elastometry will lead too often to a wrong appreciation of the degree and type of liver damage and eventually to wrong medical decision.     

Multi-phasic CT arterial portography and CT hepatic arteriography improving the accuracy of liver cancer detection

AIM:To evaluate the value of multi-phasic CT arterialportography(CTAP)and CT hepatic arteriography(CTHA)in differential diagnosis of liver diseases,and to improvethe specificity of CTAP and CTHA for liver cancerdetection.METHODS:From January 1999 to December 2002,multi-phasic CTAP and CTHA were performed in 20 patientswith suspected liver disease.CT scanning was begun 25 s,60 s and 120 s for the early,late- and delayed-phase CTAPexaminations,and 6sec,40 s and 120 s for the early-,late-and delayed-phase CTHA examinations respectively,after atranscatheter arterial injection of non-ionic contrast material.If a lesion was diagnosed as a liver cancer,transcatheterhepatic arterial chemoembolization(TACE)treatment wasperformed,and the follow-up CT was performed three orfour weeks later.RESULTS:All eighteen HCCs in 12 cases were shown asnodular enhancement on early-phasic CTHA.The densityof the whole tumor decreased rapidly on late and delayedphases,and the edge of 12 tumors(12/18)remainedrelatively hyperdense compared with the surrounding livertissue,and demonstrated as rim enhancement.All HCCswere shown as perfusion defect nodules on multi-phasicCTAP.Five tumors(5/18)were shown as rim enhancementon delayed-phasic CTAP.Rim enhancement was shown as1 to 2-mm-wide irregular,uneven and discontinuouscircumferential enhancement at late-,and delayed-phaseof CTHA or CLAP.Five pseudolesions and 4 hemoangiomaswere found in multi-phasic ClAP and CTHA.No pseudolesionsand hemoangiomas were shown as rim enhancement onlate- or delayed-phasic CTHA and CTAP.CONCLUSION:Multi-phasic CTAP and CTHA could help torecognize the false-positive findings in CTAP and CTHAimages,and improve the accuracy of CTAP and CTHA ofliver cancer detection.Li L,Liu Z,Xie ZM,Mo YX,Zheng L,Ruan CM,Chen L,WuPH.Multi-phasic CT arterial portography and CT hepaticarteriography improving the accuracy of liver cancer detection.World J Gastroenterol 2004;10(21):3118-3121http://www.wjgnet.com/1007-9327/10/3118.asp     

Evaluation of a rapid latex agglutination test (Directigen®) for the direct detection of group A streptococci from throat swabs

Summary A rapid group A beta-hemolytic streptococci (GAS) antigen detection test using latex agglutination (Directigen^®, Becton Dickinson) was compared with a conventional culture method for the direct detection of GAS from throat swabs. One throat specimen was collected from each of 229 patients. After standard inoculation onto sheep blood agar plates, all swabs were tested for GAS antigen. Of the 229 specimens tested, 46 (20%) were GAS-positive by culture. Direct latex agglutination agreed with culture in 222 of them (97%). The sensitivity of the test was 93% (43/46), the specificity 98% (179/183), the positive predictive value 91%, and the negative predictive value 98%. The detection of GAS antigen by coagglutination (Phadebact^®, Pharmacia) was also carried out. 81% (35/43) of the cultures and Directigen^®-positive specimens gave a positive coagglutination for GAS. 100% (179/179) of the cultures and Directigen^®-negative specimens were also negative by the coagglutination test. We conclude that the Directigen^® rapid latex agglutination test for the direct detection of GAS from throat swabs compares favorably with culture and has the advantage of providing same-day results.

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Zuverlässigkeit eines Schnelltests mittels Latexagglutination (Directigen^®) zum direkten Nachweis von Streptokokken der Gruppe A (SGA) im Rachenabstrich

Zusammenfassung In dieser Studie haben wir die Zuverlässigkeit eines Schnelltests mittels Latexagglutination (Directigen^®, Becton Dickinson) zum direkten Nachweis von -hämolysierenden Streptokokken der Gruppe A (SGA) im Rachenabstrich mit der konventionellen Kulturmethode verglichen. Bei 229 zufällig ausgewählten Patienten wurde jeweils ein Rachenabstrich entnommen. Alle Rachenabstriche wurden zuerst auf eine Schafblutagarplatte ausgestrichen und mittels Latex-Schnellagglutination auf das Vorhandensein von Antigenen von SGA getestet. 46 (20%) der 229 getesteten Rachenabstriche enthielten in der Kultur SGA. Das Resultat der direkten Latexagglutination stimmte in 222 Fällen (97%) mit der Kultur überein. Die Sensitivität des Tests betrug 93% (43/46), die Spezifität 98% (179/183), die positive Voraussagekraft des Tests 91%, die negative 98%. Wir haben zudem den Nachweis von SGA-Antigenen mittels Koagglutination (Phadebact^®, Pharmacia) durchgeführt. 81% (35/43) der Rachenabstriche, welche in der Kultur und im Directigen^®-Test positiv waren für SGA-Antigene, waren dies auch im Koagglutinationstest. 100% (179/179) der Rachenabstriche, welche keine SGA-Antigene in der Kultur und mittels Directigen^® aufgewiesen haben, waren mittels Koagglutinationstest ebenfalls negativ. Der Directigen^®-Schnelltest mittels Latexagglutination zum direkten Nachweis von SGA in Rachenabstrichen ist in seiner Zuverlässigkeit mit der Kulturmethode vergleichbar. Dieser Schnelltest hat den Vorteil, daß das Ergebnis am selben Tag vorliegt.

     

Can DNA sampling from the rectal mucosa be a novel tool for the detection of colorectal cancer?

Introduction  

The objective was to evaluate a new method for DNA sampling from the rectal mucosa for the detection of colorectal cancer or any clinically significant pathology in the colon and rectum.     

Is intra-operative ultrasound still useful for the detection of a hepatic tumour in the era of modern pre-operative imaging?

BackgroundThe current role of intra-operative ultrasound (IOUS) is questioned because of recent progress in medical imaging. The aim of the present study was to determine the accuracy of IOUS in the detection of a hepatic tumour (HT) compared with a pre-operative multi-detector computed tomography (MDCT) scan and magnetic resonance imaging (MRI).MethodsThis retrospective study included 418 patients evaluated using an 8-slice MDCT scan (SCAN8), 64-slice MDCT scan (SCAN64) and MRI alone or combined with a computed tomography (CT) scan. The pathological result was used as a gold standard.ResultsCorrelation rates for the number of detected lesions compared with pathology results were 0.627 for SCAN8, 0.785 for SCAN64, 0.657 for MRI and 0.913 for IOUS. Compared with pathology, the rate of concordance was significantly higher with IOUS (0.871) than with SCAN8 (0.736; P= 0.011), SCAN64 (0.792; P < 0.001) and MRI (0.742; P < 0.001). IOUS was responsible for a change in operative strategy in 16.5% of patients. Surgery was extended in 12.4%, limited in 1.7% and abandoned in 2.4%.ConclusionsCompared with cross-sectional pre-operative imaging, IOUS is still superior for the detection of HT and the planning of surgery. IOUS remains recommended as a routine procedure in patients having a hepatic resection in the era of modern pre-operative imaging.