Performance of a Semi-quantitative Multiplex Bacterial PCR Panel Compared with Standard Microbiological Laboratory Results: 396 Patients Studied with the BioFire® Pneumonia Panel

Open Forum Infectious Diseases ◽

10.1093/ofid/ofaa560 ◽

2020 ◽

Author(s):

Kenneth H Rand ◽

Stacy G Beal ◽

Kartikeya Cherabuddi ◽

Brianne Couturier ◽

Beth Lingenfelter ◽

...

Keyword(s):

Respiratory Tract ◽

Predictive Value ◽

Copy Number ◽

Clinical Laboratory ◽

Bacterial Species ◽

Turnaround Time ◽

Gram Stain ◽

Potential Pathogen ◽

Microbiological Laboratory ◽

Standard Culture

Abstract Background Microbiologic results are critical to optimal management of patients with lower respiratory tract infection, but standard methods may take several days. The multiplex PCR BioFire® Pneumonia (PN) panel detects 15 common bacterial species semi-quantitatively as copy number/mL, 8 viral species and 7 resistance genes in about an hour within the clinical laboratory. Methods We tested 396 unique endotracheal or bronchoalveolar lavage specimens with the BioFire® Pneumonia panel, and compared the bacterial detections to conventional gram stain and culture results. Results Of the 396 patients, 180 grew at least 1 bacteria that had a target on the PN panel and 177/180 (98.3%) were detected by the panel. A further 20% of patients had additional targets detected, but not found in standard culture (specificity 69%, positive predictive value 63%, and negative predictive value 98.9%). Copy number was strongly related to standard semi-quantitative growth on plates reported by the laboratory (e.g. 1+, 2+, 3+ growth), and was significantly higher in those specimens that grew a potential pathogen. Both higher copy number and bacterial detections found by the PN panel, but not found in culture, were strongly positively related to the level of WBC reported in the initial gram stain. Conclusions Higher copy number and bacterial detections per se by the PN panel are related to the host respiratory tract inflammatory response. If laboratories can achieve a rapid turnaround time, the PN panel should have a significant impact both to patient management and to antibiotic stewardship.

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Evaluation of MRSASelect™Chromogenic Medium for the Early Detection of Methicillin-ResistantStaphylococcus aureusfrom Blood Cultures

Canadian Journal of Infectious Diseases and Medical Microbiology ◽

10.1155/2013/201516 ◽

2013 ◽

Vol 24 (4) ◽

pp. e113-e116 ◽

Cited By ~ 4

Author(s):

Kanchana Manickam ◽

Andrew Walkty ◽

Philippe RS Lagacé-Wiens ◽

Heather Adam ◽

Barbara Swan ◽

...

Keyword(s):

Early Detection ◽

Antimicrobial Therapy ◽

Predictive Value ◽

Turnaround Time ◽

Blood Cultures ◽

Gram Stain ◽

Chromogenic Medium ◽

Gram Positive ◽

Microbiological Methods ◽

Gram Positive Cocci

INTRODUCTION:Staphylococcus aureusbacteremia is associated with considerable morbidity and mortality. In theory, reducing the turnaround time in reporting of methicillin-resistantS 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 MRSASelectand routine media. MRSA isolates were identified using conventional microbiological methods from routine media and using growth with the typical colony morphology (pink colony) on MRSASelectmedium.RESULTS: A total of 490 blood cultures demonstrating Gram-positive cocci in clusters on Gram stain were evaluated.S aureuswas recovered from 274 blood cultures, with 51S aureusisolates (51 of 274 [18.6%]) identified as MRSA. MRSASelectmedium 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 MRSASelectmedium 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 MRSASelectmedium 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.

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2140. Utility of Respiratory Specimen Gram Stain for Predicting Final Culture Result in Patients with Clinically Diagnosed Pneumonia

Open Forum Infectious Diseases ◽

10.1093/ofid/ofz360.1820 ◽

2019 ◽

Vol 6 (Supplement_2) ◽

pp. S725-S725

Author(s):

Jessica Seadler ◽

Terri Smith ◽

Andrew C Faust

Keyword(s):

Respiratory Tract ◽

Predictive Value ◽

Retrospective Chart Review ◽

Gram Stain ◽

Respiratory Specimen ◽

Specimen Collection ◽

Culture Morphology ◽

Culture Growth ◽

Tract Infections ◽

Collection Methods

Abstract Background Obtaining a high-quality respiratory tract specimen for Gram stain and culture in patients with suspected lower respiratory tract infections is recommended by the IDSA guidelines. However, conflicting results correlating Gram stain with final culture growth has led to questions about the utility of a respiratory specimen Gram stain. The purpose of this study was to assess the correlation of Gram stain with final culture in patients with pneumonia. Methods A retrospective chart review was conducted to evaluate adult inpatients with a diagnosis of pneumonia (based on the CDC surveillance definition) who had a respiratory specimen submitted for Gram stain and culture. A specimen was considered acceptable if less than ten epithelial cells were visualized under low power field. Each Gram stain was compared with the corresponding final culture. The primary outcome was to evaluate the correlation of Gram stain with final culture using positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity. A culture was considered negative if no bacteria were isolated or if only normal flora grew. Secondary outcomes were PPV and NPV based on antibiotic exposure prior to specimen collection, semi-quantitative number of bacteria on Gram stain, and collection method. Additionally, discordance between Gram stain and final culture morphology was evaluated. Results A total of 269 acceptable specimens were assessed. Of the 72 specimens with a positive Gram stain, 41 yielded bacteria in final culture (PPV: 56.9%). In contrast, 154 of the 197 specimens with a negative Gram stain were associated with negative final culture (NPV: 76.7%). The NPV of Gram stain was decreased when antibiotics were given for > 24 hours pre-specimen. The PPV of Gram stain improved as an increasing amount of bacteria were reported. Less invasive collection methods had a lower PPV but a higher NPV in comparison to invasive collection methods. Finally, the discordance rate between Gram stain and final culture morphology was low. Conclusion This study shows inconsistent results regarding the ability of Gram stain to predict final culture. Pneumonia should continue to be managed clinically and caution taken prior to adjusting empiric antimicrobial regimens based solely on the Gram stain. Disclosures All authors: No reported disclosures.

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The evaluation of maximum condyle-tragus distance can predict difficult airway management without exposing upper respiratory tract; a prospective observational study

BMC Anesthesiology ◽

10.1186/s12871-021-01253-5 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Hao Wu ◽

Dandan Hu ◽

Xu Chen ◽

Xuebing Zhang ◽

Min Xia ◽

...

Keyword(s):

Respiratory Tract ◽

Predictive Value ◽

Prospective Observational Study ◽

Difficult Laryngoscopy ◽

Upper Respiratory Tract ◽

Intubation Time ◽

Clinical Trial Registry ◽

Finger Width ◽

Upper Respiratory ◽

Interincisor Distance

Abstract Background Routine preoperative methods to assess airway such as the interincisor distance (IID), Mallampati classification, and upper lip bite test (ULBT) have a certain risk of upper respiratory tract exposure and virus spread. Condyle-tragus maximal distance(C-TMD) can be used to assess the airway, and does not require the patient to expose the upper respiratory tract, but its value in predicting difficult laryngoscopy compared to other indicators (Mallampati classification, IID, and ULBT) remains unknown. The purpose of this study was to observe the value of C-TMD to predict difficult laryngoscopy and the influence on intubation time and intubation attempts, and provide a new idea for preoperative airway assessment during epidemic. Methods Adult patients undergoing general anesthesia and tracheal intubation were enrolled. IID, Mallampati classification, ULBT, and C-TMD of each patient were evaluated before the initiation of anesthesia. The primary outcome was intubation time. The secondary outcomes were difficult laryngoscopy defined as the Cormack-Lehane Level > grade 2 and the number of intubation attempts. Results Three hundred four patients were successfully enrolled and completed the study, 39 patients were identified as difficult laryngoscopy. The intubation time was shorter with the C-TMD>1 finger group 46.8 ± 7.3 s, compared with the C-TMD<1 finger group 50.8 ± 8.6 s (p<0.01). First attempt success rate was higher in the C-TMD>1 finger group 98.9% than in the C-TMD<1 finger group 87.1% (P<0.01). The correlation between the C-TMD and Cormack-Lehane Level was 0.317 (Spearman correlation coefficient, P<0.001), and the area under the ROC curve was 0.699 (P<0.01). The C-TMD < 1 finger width was the most consistent with difficult laryngoscopy (κ = 0.485;95%CI:0.286–0.612) and its OR value was 10.09 (95%CI: 4.19–24.28), sensitivity was 0.469 (95%CI: 0.325–0.617), specificity was 0.929 (95%CI: 0.877–0.964), positive predictive value was 0.676 (95%CI: 0.484–0.745), negative predictive value was 0.847 (95%CI: 0.825–0.865). Conclusion Compared with the IID, Mallampati classification and ULBT, C-TMD has higher value in predicting difficult laryngoscopy and does not require the exposure of upper respiratory tract. Trial registration The study was registered on October 21, 2019 in the Chinese Clinical Trial Registry (ChiCTR1900026775).

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44. Reevaluation of copy number variant (CNV) classifications in the clinical laboratory setting: challenges, insights, and experiences with a laboratory-initiated process

Cancer Genetics ◽

10.1016/j.cancergen.2021.01.055 ◽

2021 ◽

Vol 252-253 ◽

pp. S15

Author(s):

Denise I Quigley ◽

Zoe K Lewis ◽

Timothy Tidwell ◽

Adam Clayton ◽

Brandon Chandler ◽

...

Keyword(s):

Copy Number ◽

Clinical Laboratory ◽

Copy Number Variant ◽

Laboratory Setting

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Clinical risk scores for the early prediction of severe outcomes in patients hospitalized for COVID-19

Internal and Emergency Medicine ◽

10.1007/s11739-020-02617-4 ◽

2021 ◽

Author(s):

Walter Ageno ◽

◽

Chiara Cogliati ◽

Martina Perego ◽

Domenico Girelli ◽

...

Keyword(s):

Hospital Admission ◽

Predictive Value ◽

Clinical Laboratory ◽

Area Under The Curve ◽

Orotracheal Intubation ◽

Risk Scores ◽

Algorithm Selection ◽

Derivation Cohort ◽

Neutrophil Lymphocyte Ratio ◽

Predictive Risk

AbstractCoronavirus disease of 2019 (COVID-19) is associated with severe acute respiratory failure. Early identification of high-risk COVID-19 patients is crucial. We aimed to derive and validate a simple score for the prediction of severe outcomes. A retrospective cohort study of patients hospitalized for COVID-19 was carried out by the Italian Society of Internal Medicine. Epidemiological, clinical, laboratory, and treatment variables were collected at hospital admission at five hospitals. Three algorithm selection models were used to construct a predictive risk score: backward Selection, Least Absolute Shrinkage and Selection Operator (LASSO), and Random Forest. Severe outcome was defined as the composite of need for non-invasive ventilation, need for orotracheal intubation, or death. A total of 610 patients were included in the analysis, 313 had a severe outcome. The subset for the derivation analysis included 335 patients, the subset for the validation analysis 275 patients. The LASSO selection identified 6 variables (age, history of coronary heart disease, CRP, AST, D-dimer, and neutrophil/lymphocyte ratio) and resulted in the best performing score with an area under the curve of 0.79 in the derivation cohort and 0.80 in the validation cohort. Using a cut-off of 7 out of 13 points, sensitivity was 0.93, specificity 0.34, positive predictive value 0.59, and negative predictive value 0.82. The proposed score can identify patients at low risk for severe outcome who can be safely managed in a low-intensity setting after hospital admission for COVID-19.

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Validation of the SavvyCheckTM Vaginal Yeast Test for Screening Pregnant Women for Vulvovaginal Candidosis: A Prospective, Cross-Sectional Study

Journal of Fungi ◽

10.3390/jof7030233 ◽

2021 ◽

Vol 7 (3) ◽

pp. 233

Author(s):

Philipp Foessleitner ◽

Herbert Kiss ◽

Julia Deinsberger ◽

Julia Ott ◽

Lorenz Zierhut ◽

...

Keyword(s):

Pregnant Women ◽

Predictive Value ◽

Point Of Care ◽

Cross Sectional Study ◽

Control Group ◽

Gram Stain ◽

Cross Sectional ◽

Point Of Care Test ◽

Increased Risk ◽

Vulvovaginal Candidosis

Pregnant women have an increased risk of vulvovaginal candidosis. Recurrent candidosis is under debate as a contributor to preterm birth, and vertical transmission may cause diaper dermatitis and oral thrush in the newborn. Apart from cultural methods, the gold standard for diagnosing candidosis is Gram staining, which is time-consuming and requires laboratory facilities. The objective of this prospective study was to validate a point-of-care vaginal yeast detection assay (SavvyCheckÔ Vaginal Yeast Test) and to evaluate it in asymptomatic pregnant women. We enrolled 200 participants, 100 of whom had vulvovaginal candidosis according to Gram stain (study group) and 100 were healthy pregnant controls (control group). Of these, 22 participants (11%) had invalid test results. The point-of-care test of the remaining 85 and 93 study participants in the study and control groups, respectively, showed a sensitivity of 94.1%, specificity of 98.9%, positive predictive value of 90.3%, and negative predictive value of 99.4% when compared with Gram stain. In conclusion, we found a high correlation between the SavvyCheckÔ Vaginal Yeast Test and Gram-stained smears during pregnancy. This suggests a potential role of this point-of-care test as a screening tool for asymptomatic pregnant women in early gestation.

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The Predictive Value of Clinical Laboratory Test Results

American Journal of Clinical Pathology ◽

10.1093/ajcp/69.1.32 ◽

1978 ◽

Vol 69 (1) ◽

pp. 32-35 ◽

Cited By ~ 3

Author(s):

Philip G. Archer

Keyword(s):

Laboratory Test ◽

Predictive Value ◽

Clinical Laboratory ◽

Test Results ◽

Clinical Laboratory Test ◽

Laboratory Test Results

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Nontypeable Haemophilus influenzae infection impedes Pseudomonas aeruginosa colonization and persistence in mouse respiratory tract

Infection and Immunity ◽

10.1128/iai.00568-21 ◽

2021 ◽

Author(s):

Natalie Lindgren ◽

Lea Novak ◽

Benjamin C. Hunt ◽

Melissa S. McDaniel ◽

W. Edward Swords

Keyword(s):

Pseudomonas Aeruginosa ◽

Respiratory Tract ◽

Haemophilus Influenzae ◽

Respiratory Infections ◽

Bacterial Species ◽

Young Patients ◽

Nontypeable Haemophilus Influenzae ◽

Potential Significance ◽

And Diffusion

Patients with cystic fibrosis (CF) experience lifelong respiratory infections which are a significant cause of morbidity and mortality. These infections are polymicrobial in nature, and the predominant bacterial species undergo a predictable series of changes as patients age. Young patients have populations dominated by opportunists that are typically found within the microbiome of the human nasopharynx, such as nontypeable Haemophilus influenzae (NTHi); these are eventually supplanted and the population within the CF lung is later dominated by pathogens such as Pseudomonas aeruginosa ( Pa ). In this study, we investigated how initial colonization with NTHi impacts colonization and persistence of Pa in the respiratory tract. Analysis of polymicrobial biofilms in vitro by confocal microscopy revealed that NTHi promoted greater levels of Pa biofilm volume and diffusion. However, sequential respiratory infection of mice with NTHi followed by Pa resulted in significantly lower Pa as compared to infection with Pa alone. Coinfected mice also had reduced airway tissue damage and lower levels of inflammatory cytokines as compared with Pa infected mice. Similar results were observed after instillation of heat-inactivated NTHi bacteria or purified NTHi lipooligosaccharide (LOS) endotoxin prior to Pa introduction. Based on these results, we conclude that NTHi significantly reduces susceptibility to subsequent Pa infection, most likely due to priming of host innate immunity rather than a direct competitive interaction between species. These findings have potential significance with regard to therapeutic management of early life infections in patients with CF.

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Physician Satisfaction With Clinical Laboratory Services: A College of American Pathologists Q-Probes Study of 138 Institutions

Archives of Pathology & Laboratory Medicine ◽

10.5858/133.1.38 ◽

2009 ◽

Vol 133 (1) ◽

pp. 38-43

Author(s):

Bruce A. Jones ◽

Leonas G. Bekeris ◽

Raouf E. Nakhleh ◽

Molly K. Walsh ◽

Paul N. Valenstein

Keyword(s):

Quality Improvement ◽

Clinical Laboratory ◽

Turnaround Time ◽

Physician Satisfaction ◽

Reliability Of Results ◽

Improvement Program ◽

Valuable Component ◽

Laboratory Services ◽

Survey Results ◽

High Level

Abstract Context.—Monitoring customer satisfaction is a valuable component of a laboratory quality improvement program. Objective.—To survey the level of physician satisfaction with hospital clinical laboratory services. Design.—Participating institutions provided demographic and practice information and survey results of physician satisfaction with defined aspects of clinical laboratory services, rated on a scale of 1 (poor) to 5 (excellent). Results.—One hundred thirty-eight institutions participated in this study and submitted a total of 4329 physician surveys. The overall satisfaction score for all institutions ranged from 2.9 to 5.0. The median overall score for all participants was 4.1 (10th percentile, 3.6; 90th percentile, 4.5). Physicians were most satisfied with the quality/reliability of results and staff courtesy, with median values of excellent or good ratings of 89.9%. Of the 5 service categories that received the lowest percentage values of excellent/good ratings (combined scores of 4 and 5), 4 were related to turnaround time for inpatient stat, outpatient stat, routine, and esoteric tests. Surveys from half of the participating laboratories reported that 96% to 100% of physicians would recommend the laboratory to other physicians. The category most frequently selected as the most important category of laboratory services was quality/reliability of results (31.7%). Conclusions.—There continues to be a high level of physician satisfaction and loyalty with clinical laboratory services. Test turnaround times are persistent categories of dissatisfaction and present opportunities for improvement.

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