Clinical Test Results Research Articles

Functional Outcome of Management of Isolated Supraspinatus Tendon Tear by Mini-open repair TechniqueA Prospective Interventional Study

Introduction: Rotator Cuff Injuries (RCIs) are common shoulder injuries, and the supraspinatus muscle, which is part of the rotator cuff, plays a crucial role in shoulder abduction. The mini-open repair technique offers several advantages, including being less invasive, leading to reduced postoperative morbidity, and shorter operative times. Aim: The aim of this prospective interventional study was to assess the functional consequences of open microscopic repair and the functional implications of supraspinatus tendon repair following the procedure and during the postoperative healing period. Materials and Methods: The study was conducted at the Department of Orthopaedics at Great Eastern Medical School and Hospital in Srikakulam, Andhra Pradesh, India. The study duration was one year, from July 2020 to July 2022. A total of 120 patients aged between 20 and 60 years were included, and all surgeries were performed by the same surgeon. Patients were followed up for one year and evaluated with ConstantMurley Score (CMS) system. Patient data were analysed based on gender, age, degree of tears, clinical test results, and postoperative scores. Levene’s test was used to determine variance homogeneity, and the Student’s t-test (two-tailed, dependent) was used to determine the statistical significance of study parameters on a continuous scale within each group. Results: The study included 120 patients (84 males and 36 females), and the majority of them had traumatic tears. When data was analysed based on patient age, the majority were between 46 and 50 years (33 patients, 27%), followed by the age group of 41-45 years. At the end of one year, the outcomes were excellent in 68 patients, good in 24 patients, satisfactory in 16 patients, and poor in 12 patients. Conclusion: Based on the results of the mini-open technique, the authors concluded that mini-open rotator cuff repair resulted in superior repair integrity and shoulder function.

Selection of the best endodontic treatment option using data mining

Introduction: The presence of postendodontic pain is an important issue, which can affect the patients' quality of life. Appropriate treatment selection, based on specific characteristics (e.g., clinical test results and patients' demographics), may reduce postendodontic pain. We aimed to evaluate the relationship of data mining algorithms in longitudinal data of postendodontic pain and treatment allocation to predict the best treatment option. Materials and Methods: The pain data of an original multicenter randomized clinical trial with two study arms, pulpotomy with mineral trioxide aggregate (PMTA) (n = 188) and root canal therapy (RCT) (n = 168), were used. The linear mixed-effects model and predictive algorithms were fitted in accordance with the personal characteristics of patients and diagnostic test results to determine the best treatment option. Using SPSS 23, SAS 9.1, and WEKA 3.6.9, the preferred treatment was identified via comparing the areas below the receiver operating characteristic curves and identifying the most appropriate algorithm. In addition, a decision tree was used to allocate the best type of treatment modality to reduce posttreatment pain. Results: For < 18-year-old patients with irreversible pulpitis (IP) based on cold test and >18-year-old patients whose electrical pulp test (EPT) exhibited IP, the chosen treatment would be RCT (P < 0.05). However, for >18-year-old patients with IP based on cold test and <18-year-old patients whose EPT revealed IP, the recommended treatment would be PMTA (P < 0.05). Conclusions: The decision tree model seems to be able to predict the reduction of postendodontic pain in ~65% of patients if they receive optimal treatment.

Perceptual measurement of articulatory goodness in young children: Relationships with age, speech sound acquisition, and intelligibility

ABSTRACT Speech language pathologists regularly use perceptual methods in clinical practice to assess children’s speech. In this study, we examined relationships between measures of speech intelligibility, clinical articulation test results, age, and perceptual ratings of articulatory goodness for children. We also examined the extent to which established measures of intelligibility and clinical articulation test results predicted articulatory goodness ratings, and whether goodness ratings were influenced by intelligibility. A sample of 164 (30–47 months) typically developing children provided speech samples and completed a standardised articulation test. Single word intelligibility scores and ratings of articulatory goodness were gathered from 328 naïve listeners; scores on a standardised articulation test were obtained from each child. Bivariate Pearson correlation, linear regression, and linear mixed effects modelling were used for analysis. Results showed that articulatory goodness ratings had the highest correlation with intelligibility, followed by age, followed by articulation score. Age and clinical articulation scores were both significant predictors of goodness ratings, but articulation scores made only a small contribution to prediction. Articulatory goodness ratings were substantially lower for unintelligible words compared to intelligible words, but articulatory goodness scores increased with age at the same rate for unintelligible and intelligible words. Perceptual ratings of articulatory goodness are sensitive to developmental changes in speech production (regardless of intelligibility) and yield a different kind of information than clinical articulation scores from standardised measures.

Plasma levels of intestinal fatty-acid binding protein (I-FABP), abdominal distension and hydrogen concentration after lactitol small intestinal bacterial overgrowth (SIBO) test.

Breath tests with glucose, lactulose or lactitol are useful for diagnosis of small intestinal bacterial overgrowth (SIBO). Nevertheless, they have suboptimal sensitivity and specificity and, indeed, are positive in a considerable number of patients with irritable bowel syndrome (IBS). The complexity in the management of patients with functional intestinal disorders and the availability of these tests are leading to frequent diagnoses of SIBO. Intestinal Fatty-Acid Binding protein (I-FABP) is a protein present in the cytosol of intestinal epithelial cells. Its plasmatic levels have been related to different enteropathies and, therefore, could be a marker of early intestinal damage with unconfirmed clinical utility. Hence, we have studied the plasmatic I-FABP level of patients who are requested a lactitol test to confirm SIBO and related it to clinical and laboratory characteristics and SIBO test results.

The second wave of COVID-19 wreaked havoc: A look at clinical and laboratory parameters of survivors and non-survivors admitted to Intensive Care Unit, a single-centered retrospective study.

The second wave of COVID-19 was disastrous and claimed many lives in India and abroad. The most challenging task was to provide the required treatment as per the patient's condition, within a limited span of time. The lack of prognostic predictors at the time of admission led to failure in prioritizing the patient's need for intensive care. This study was conducted to find out the clinical and laboratory parameters at the time of admission to ICU as predictors of outcomes in COVID-19 patients, which can help in judicious utilization of the available resources for better patient care. Study comprises of 161 ICU admitted patients. Study of clinical traits, comorbidities, test results, and demographic variables were carried out among survivors and non-survivor. Maximum death were patients of age group 21-30 years and male gender. Mortality in hypertensives, diabetics, and patients with sepsis were found to be statistically significant. Patients who developed ARDS and pneumonia or needed ventilation died invariably. High levels of laboratory parameters like IL-6, LDH, PT, INR, aPTT, ferritin, WBC count, and D-dimer were significantly associated with poor outcomes and at a particular cutoff had optimum sensitivity and specificity to predict mortality in ICU admitted COVID-19 patients. At the same time, low lymphocyte count and PaO2/FiO2 ratio was significantly associated with bad prognosis (P < 0.05). This paper will help in prioritizing patients in ICU who need special attention especially at the time of meager supply of resources.

Clinical and laboratory features of different types of cancer-associated thrombosis.

Background: Patients with cancer showed a high incidence of venous thromboembolism (VTE) with a poor prognosis. The risk factors for VTE in different types of cancers may differ. Methods: The clinical features and laboratory test results of cancer patients with VTE in Henan Provincial People's Hospital from 2014 to 2020 were evaluated and compared. Results: Among the eligible patients, gastrointestinal cancer (GI cancer), lung cancer and gynecological cancer accounted for the top three. This study included 49 patients with GI cancer, 31 with lung cancer and 31 with gynecological cancer. The proportion of patients who underwent surgery in GI cancer or gynecological cancer group was significantly higher than that for lung cancer (69.4% and 80.6% vs 12.9%, both P<0.001). Red blood cell (RBC) and hemoglobin (HGB) levels were lower in the gynecological cancer group than that in the lung cancer group (P = 0.014 and 0.029, respectively), while red cell distribution width (RDW) was higher in the GI cancer group than that in the lung cancer group and gynecological cancer group (P = 0.047 and 0.010, respectively). Prothrom bin time (PT) was shorter in the gynecological cancer group than that in the GI and lung cancer group (P = 0.003 and P = 0.002, respectively). The activated partial thromboplastin time (APTT) in the lung cancer group was longer than that in the GI and gynecological cancer group (P = 0.029 and 0.003, respectively). There was no difference in LOS and successful treatment rate among the groups. However, the VTE cure rate in the gynecological cancer group is higher than that in the GI cancer group (90.3% vs 61.2%, P = 0.005). The probability of continuing to take anticoagulants after discharge in the gynecological cancer group is lower than that in the GI and lung cancer groups (6.5% vs 30.6% and 32.3%, P = 0.011 and 0.022 respectively). Conclusion: VTE risk factors of different types of cancers and laboratory test results were not exactly the same. Thrombosis prevention and treatment should be implemented according to the characteristics of the different types of cancer.

Resistance Trends of Antiretroviral Agents in People with Human Immunodeficiency Virus in Korea, 2012 - 2020.

Domestic data on antiretroviral drug (ARV) resistance are limited, while alterations in ARV resistance are expected as the incidence of human immunodeficiency virus (HIV) infection increases. We evaluated the ten-year change in ARV resistance in people with HIV (PWH) in Korea. Adults aged ≥19 years and diagnosed with HIV infection between January 2010 and December 2020 at a 750-bed municipal hospital were retrospectively reviewed. Data on clinical characteristics and resistance mutation test results were collected. The study population was divided into three-year intervals according to diagnosed year and their clinical characteristics were compared. A total of 248 PWH were analyzed, and ARV resistance was detected in 30 of them (12.1%). Resistance was detected most frequently in PWH aged ≤29 years (16, 6.5%), and the median percentage of resistance detection per year was 14.3% (interquartile range, 12.7 - 16.1). The trend of the overall prevalence of ARV resistance mutations slightly decreased and then increased over time (15.3% in 2012 - 2014, 9.6% in 2015 - 2017, and 12.9% in 2018 - 2020). The prevalence of the non-nucleoside reverse transcriptase inhibitor (NNRTI) resistance markedly decreased over time (15.3% in 2012 - 2014, 8.7% in 2015 - 2017, and 2.4% in 2018-2020), while that of protease inhibitor (PI) and integrase strand transfer inhibitor (INSTI) increased from 0 until 2018 to 3.5% and 8.2% in 2018 - 2020, respectively. The trend of NNRTI resistance has decreased over time, and resistance to PIs and INSTIs increased from 2018. Therefore, continuous monitoring of ARV resistance pattern is necessary.

Basic assessment of chronic cough in primary care and referral pathways of patients to different specialists.

Chronic cough (CC; cough that lasts 8 weeks or longer) poses major effective assessment challenges. Assessment of CC may vary considerably among medical specialists. The aim was to evaluate similarities and consistency of responses across different specialists when performing a basic assessment of CC patients in primary care, and referring patients based on clinical findings or test results. A modified Delphi approach was used. A survey with 74 statements on initial assessment of CC and referral pathways was addressed to a panel of different specialists, who voted the statements in two rounds. Seventy-seven physicians [18 primary care physicians (PCPs), 24 pulmonologists, 22 allergists, and 13 ear, nose, and throat specialists] from the National Healthcare System of Spain answered the questionnaire. After two rounds, the panel reached a consensus on 63 out of the 74 proposed items (85.1%). Consensus was not reached among the panelists of at least one specialty on 15 out of these 63 agreed items. The panel agreed on those clinical aspects that should be evaluated by PCPs in all patients with CC including the impact of CC on quality of life. Agreement was reached on initial actions to be taken in primary care, including substitution of drugs that may induce cough, performing a chest X-ray, introduction of anti-reflux measures, initiation of empirical anti-reflux pharmacological therapy in some cases, and performing a spirometry with bronchodilator test and hemogram if an etiological diagnosis was not reached. The panelists agreed on a list of diseases that PCPs should assess before referring CC patients. Algorithms were developed for initial assessment and targeted referral of patients with CC from primary care. This study provides the perspective of different medical specialists on how to perform a basic assessment of CC patients in primary care and how and when to refer patients to other specialists.

Association between sensitivity to thyroid hormone indices and osteoporosis in euthyroid patients with type 2 diabetes mellitus.

Thyroid hormones are known to regulate bone metabolism and may influence bone mineral density (BMD), as well as the risk of osteoporosis (OP) and fractures in patients with type 2 diabetes mellitus (T2DM). Recently, sensitivity to thyroid hormone indices has been linked with T2DM and OP independently. However, the relationship between thyroid hormone sensitivity and OP in euthyroid T2DM patients has yet to be investigated. The aim of this study was to determine the association between sensitivity to thyroid hormone indices and the risk of OP in euthyroid patients with T2DM. This study employed a retrospective, cross-sectional design and utilized data acquired from the Cangzhou Central Hospital in China between 2019 and 2020. We retrospectively analyzed the data of 433 patients with T2DM for anthropometric measurements, clinical laboratory test results, and BMD. The thyroid-stimulating hormone index, thyrotroph thyroxine resistance index, and thyroid feedback quantile-based index (TFQI) were calculated to determine thyroid hormone sensitivity. Finally, multivariable logistic regression, generalized additive models, and subgroup analysis were performed to detect the association between sensitivity to thyroid hormone indices and the risk of OP in these patients. We did not observe a statistically significant linear relationship between sensitivity to thyroid hormones indices and OP after covariate adjustment. However, a nonlinear relationship existed between TFQI and the prevalence of OP. The inflection point of the TFQI was at -0.29. The effect sizes (odds ratio) on the left and right of the inflection point were 0.07 [95% confidence interval (CI): 0.01-0.71; p = 0.024] and 2.78 (95% CI: 1.02-7.58; p = 0.046), respectively. This trend was consistent in older female patients with higher body mass index (BMI; 25-30 kg/m2). An approximate U-shaped relationship was observed between sensitivity to thyroid hormone indices and OP risk in euthyroid patients with T2DM with variations in sex, age, and BMI. These findings provide a new perspective to elucidate the role of thyroid hormones in OP, specifically in patients with T2DM.

Application of Machine Learning Tools in the Evaluation of the Risk of Falls in the Elderly: An Integrative Review

This integrative review seeks to present an overview of the application of machine learning (ML) tools in the assessment of the risk of falls in the elderly. We searched the CAPES and IEEE Xplore Periodical databases, articles published in English, Portuguese and Spanish, in the last eleven years. Thirteen articles were selected. Most studies use data from sensors to classify the risk of falling and compare the results obtained with results of clinical tests or history of falls. Some studies carried out the selection of characteristics of the collected signals. Research that compared CI tools and conventional scales pointed to a certain superiority of the former. In the selected articles, Multilayer Perceptron (MLP) neural networks were the most explored. It was possible to observe that the ML tools can be applied in the assessment of the risk of falls in the elderly as a classification resource, showing good results.

Utilization of Automated Notification System of Epidemic Based on Clinical Microbiological Test Results

Utilization of Automated Notification System of Epidemic Based on Clinical Microbiological Test Results

Novel Magnetic-Bead-Assisted Sequential Extraction Method for Liquid Chromatography-Mass Spectrometry (MS)/MS of Components with Diverse Properties: Gastrin Determination as a Case Study

Sample preparation is the rate-limiting step in liquid chromatography-mass spectrometry (LC-MS)/MS-based clinical analysis when target analytes possess significantly different properties. Repeated solid-phase extraction (SPE) processes are typically required, resulting in low throughput and excessive consumption of labor, materials, and samples. In this study, we developed and validated a feasible and productive method to enrich target analytes with different properties during a single operation, while sufficiently removing matrix interferences to meet LC-MS/MS requirements. Gastrin determination was selected as the subject of this study. An automated magnetic-bead-assisted sequential extraction (MBASE) workflow was developed to simultaneously isolate nonsulfated gastrin-17 (G17ns), sulfated gastrin-17 (G17s), nonsulfated gastrin-34 (G34ns), and sulfated gastrin-34 (G34s) from human serum. It performs two different ion-exchange-based magnetic-bead extraction steps on one sample aliquot to produce one combined extract for LC-MS/MS analysis. When compared with the traditional SPE process, the MBASE workflow saves over 75% time and labor expenses as well as over 90% material cost, while providing even higher extraction efficiency. The MBASE LC-MS/MS method was validated as accurate and robust. Clinical sample test results demonstrated that the conventional chemiluminescence immunoassay method significantly under-estimated total gastrins in human serum, and the MBASE LC-MS/MS method could serve as an ideal tool to provide a comprehensive and accurate gastrin profile.

Results of clinical validation of a new method of brachial plexus trunk distraction after neuroraphy

The paper describes the results of clinical testing of an apparatus for dosed traction of brachial plexus trunks. It is shown that in the presence of a 5 cm diastasis, it is possible to connect the nerve fragments and perform neurorhaphy without tension by bringing the shoulder to the head and bring the shoulder to the physiological position two and a half months after the reconstructive surgery.

Applying machine learning methods to predict the hospital re-admission within 30 days of total hip arthroplasty and hemiarthroplasty

BackgroundTotal hip arthroplasty (THA) and hemiarthroplasty are common treatments for severe hip joint disease. To predict the probability of re-admission after discharge when patients are hospitalized will support providing appropriate health education and guidance. MethodsThe research aims to use logistic regression (LR), decision trees (DT), random forests (RF), and artificial neural networks (ANN) to establish predictive models and compare their performances on re-admissions within 30 days after THA or hemiarthroplasty. The data of this study includes patient demographics, physiological measurements, disease history, and clinical laboratory test results. ResultsThere were 508 and 309 patients in the THA and hemiarthroplasty studies respectively from September 2016 to December 2018. The accuracies of the four models LR, DT, RF, and ANN in the THA experiment are 94.3%, 93.2%, 97.3%, and 93.9%, respectively. In the hemiarthroplasty experiment, the accuracies of the four models are 92.4%, 86.1%, 94.2%, and 94.8%, respectively. Among these, we found that the RF model has the best sensitivity and ANN model has the best area under the receiver operating characteristic (AUROC) score in both experiments. ConclusionsThe THA experiment confirmed that the performance of the RF model is better than the other models. The key factors affecting the prognosis after THA surgery are creatinine, sodium, anesthesia duration, and dialysis. In the hemiarthroplasty experiment, the ANN model showed more accurate results. Poor kidney function increases the risk of hospital re-admission. This research highlights that RF and ANN model perform well on the hip replacement surgery outcome prediction.

A novel missense mutation of the STK11 gene in a Chinese family with Peutz-Jeghers syndrome

BackgroundPeutz-Jeghers syndrome (PJS) is a rare autosomal dominant inherited disease caused by mutations in the Serine-Threonine Kinase 11 (STK11) gene. This study aimed to diagnose a Chinese pedigree with PJS and to expand the spectrum of STK11 variants.MethodsWe performed an inductive analysis of clinical features, gastrointestinal endoscopy, radiologic imaging, and pathological findings in a Chinese family with PJS. Whole-exome sequencing (WES), Sanger sequencing, and STK11 protein 3D structure prediction were performed for establishing a molecular diagnosis.ResultsThe proband, her mother, and grandfather presented with pigmentation spots on lips, oral mucosa, and fingers. Her mother and grandfather also had pigmentation spots on face and feet, while her brother had pigmentation spots only on the lower lip. On endoscopy, polyps were discovered in the proband, her mother, and grandfather. A novel heterozygous mutation (c.521A > C) in exon 4 of STK11 was identified in all four patients, leading to a change from histidine to proline in amino acid 174. The variable site p.H174 was highly conserved in different species on multiple sequence alignment analysis.ConclusionsWe diagnosed a Chinese pedigree with PJS based on clinical features, gastrointestinal endoscopy, and genetic testing results. Our results expanded the spectrum of STK11 variants, which will be helpful for genetic counseling.

Risk Score for Prediction of Acute Kidney Injury in Patients with Acute ST-Segment Elevation Myocardial Infarction.

Acute kidney injury (AKI) is an important comorbidity of ST-Segment Elevation Myocardial Infarction (STEMI) and worsens the prognosis. The purpose of this study was to investigate the relationship between clinical data, test results, surgical findings, and AKI in STEMI patients and to develop a simple, practical model for predicting the risk of AKI. Prognostic prediction research with clinical risk score development was conducted. The data used for model development was derived from the database of the Henan Province Cardiovascular Disease Clinical Data and Sample Resource Bank Engineering Research Center. The data used for external validation was derived from the China Chest Pain Center database. The study endpoint was defined as the occurrence of AKI. Logistic regression analysis was used to identify independent predictors of AKI. Logistic coefficients of each predictor were used for score weighting and transformation. The predictive performance of the newly derived risk scores was validated, respectively, by receiver operating characteristic (ROC) regression in the development population and the external validation population. A total of 364 patients, 57 (15.6%) with AKI and 307 (84.4%) without AKI, were included for score derivation. The validation crowd includes 88 STEMI patients in different institutions. A total of 11 potential predictors were explored under the multivariable logistic regression model. The new risk score was based on five final predictors which were age > 72 years, ejection fraction of no more than 40%, baseline serum creatinine > 102.7 mmol/L, red blood cell distribution width > 13.15, and culprit lesion located in the middistal segment. With only five predictor variables, the score predicted the risk of AKI with the effective discriminative ability (area under the receiver operating characteristic curve (AuROC): 0.721, 95% confidence interval (CI): 0.652-0.790). In the external validation, the newly developed score confirmed a similar discrimination as the crowd used for derivation (AuROC: 0.731, 95% CI: 0.624-0.838). The newly developed score was proved to have good predictive performance and could be practically applied for risk stratification of AKI in STEMI patients.

Selectively targeted blastocyst embryo transfer: optimizing ivf pregnancy results while minimizing risks and side effects

Research Question: Is single embryo transfer a reasonable option. Design: Material and methods: This is a retrospective cohort study conducted in a single IVF center. These patients consisted of 96 patients using egg donors and 92 patients using their own eggs for a total of 188 patients undergoing IVF-ICSI. Results: Among 96 patients who received donor eggs, 59 women (61%) were positive for pregnancy tests, resulting in 40 live births (68% per Pregnancy). On the other hand, of 92 patients who received their own egg, 34 patients (37%) were positive in terms of pregnancy tests, resulting in 15 live births (44% per pregnancy). Overall, of all 55 live births, 24 were multiple pregnancies. Interestingly, all multiple pregnancies occured in patients &lt;35 years of age. All of these multiples resulted from the transfer of two blastocysts of grade A. Conclusion: These results corroborate and enhance the various reproductive society recommendations that a selective single embryo transfer at the blastocyst stage and above would be a feasible option in patients less than 38 years of age, especially in patients using egg donors younger than 33 years of age, while resulting in a reasonably high successful singleton live birth rate. This is based on the predicted calculation of a 42.5% singleton live birth per egg donor pregnancy, and a 28% singleton live birth per pregnancy for patients using their own eggs. Summary: Patients who had Blastocyst or above grade A had a 63.7% biochemical or clinical positive pregnancy test result and a 40.7% Live birth. Whilst, patients with blastocysts of other grades or lower stages of development, resulted in 30.7% positive biochemical or clinical pregnancy with 10.7% live birth.

A novel compound heterozygous BEST1 gene mutation in two siblings causing autosomal recessive bestrophinopathy

PurposeTo describe the clinical features, imaging characteristics, and genetic test results associated with a novel compound heterozygous mutation of the BEST1 gene in two siblings with autosomal recessive bestrophinopathy.MethodsTwo siblings underwent a complete ophthalmic examination, including dilated fundus examination, fundus photography, fundus autofluorescence imaging, spectral-domain optical coherence tomography, fluorescein angiography, electroretinography, and electrooculography. A clinical diagnosis of autosomal recessive bestrophinopathy was established based on ocular examination and multimodal retinal imaging. Subsequently, clinical exome sequencing consisting of a panel of 6670 genes was carried out to confirm the diagnosis and assess genetic alterations in the protein-coding region of the genome of the patients. The identified mutations were tested in the two affected siblings and one of their parents.ResultsTwo siblings (a 17-year-old female and a 15-year-old male) presented with reduced visual acuity and bilaterally symmetrical subretinal deposits of hyperautofluorescent materials in the posterior pole, which showed staining in the late phase of fluorescein angiogram. Spectral-domain optical coherence tomography demonstrated hyperreflective subretinal deposits and subretinal fluid accumulation. Both patients shared two mutations in the protein-coding region of the BEST1 gene, c.103G > A, p.(Glu35Lys) and c.313C > A, p.(Arg105Ser) (a novel disease-causing mutation). Sanger sequencing confirmed that the unaffected mother of the proband was carrying p.(Glu35Lys) variant in a heterozygous state.ConclusionsWe have identified and described the phenotype of a novel disease-causing mutation NM_004183.4:c.313C > A, p.(Arg105Ser) in a heterozygous state along with a previously reported mutation NM_004183.4:c.103G > A, p.(Glu35Lys) of the BEST1 gene in two related patients with autosomal recessive bestrophinopathy.

791. ICU Provider Overestimation of Ventilator-Associated Pneumonia Diagnostic Probability: An Opportunity for Diagnostic Stewardship

Abstract Background Overdiagnosis of ventilator-associated pneumonia (VAP) is common in intensive care units (ICUs). Because VAP is a clinical diagnosis without an easily accessible confirmatory diagnostic test, understanding how ICU physicians practice diagnostic reasoning in suspected VAP is vital to informing diagnostic stewardship efforts. We aimed to assess the accuracy of ICU practitioner estimates of VAP diagnostic probability. Methods We conducted a survey of physicians at Michigan Medicine ICUs. Providers were presented with clinical vignettes (Figure 1) in which mechanically ventilated patients developed clinical signs suggestive of VAP and then had radiographic/microbiologic tests performed. Providers were asked to estimate the probability of VAP before and after each presented clinical sign or test result, which were then used to impute provider-estimated likelihood ratios (pLRs) for each clinical sign and diagnostic test. Provider-estimated probabilities and LRs were compared to evidence-based VAP probabilities and LRs (eLRs) derived from systematic reviews and meta-analyses. Survey Case Example. Results Of 102 survey respondents, 54% felt moderately to extremely confident in their ability to accurately diagnose VAP. Providers significantly overestimated the pre and post-test probability of VAP in all clinical scenarios (provider-estimated VAP diagnostic probabilities are visualized using density plots relative to evidence-based diagnostic probability in Figure 2). Median pLRs for nearly all VAP clinical signs and diagnostic tests were also significantly higher than eLRs (Figure 3), most notably for isolated purulent endotracheal secretions (pLR 1.54 vs eLR 0.76, p&amp;lt; 0.01), positive chest radiograph (pLR 6.0 vs eLR 3.55, p&amp;lt; 0.01), and positive bronchoalveolar lavage culture (pLR 5.7 vs eLR 1.37, p&amp;lt; 0.01). Density Plots of Provider-Estimated vs Evidence-Based Diagnostic Probability of Ventilator-Associated Pneumonia. Provider-Estimated vs Evidence-Based Diagnostic Likelihood Ratios for Clinical Signs and Test Results Related to Ventilator-Associated Pneumonia. Conclusion Physicians routinely overestimated the diagnostic probability of VAP and the positive LRs of possible VAP clinical signs, as well as VAP diagnostic radiographic and microbiologic tests. Educational initiatives addressing and calibrating ICU providers’ perceptions of VAP diagnostic probability warrant investigation as an antimicrobial stewardship tool. Disclosures Owen Albin, MD, Charles River Laboratory: Advisor/Consultant|Cipla Pharmaceuticals: Advisor/Consultant|Shionogi Inc: Advisor/Consultant.

432. Ward-level Variation in Transmission of MRSA in Veterans Affairs Hospitals

Abstract Background In 2007, the Department of Veterans Affairs (VA) implemented the methicillin-resistant Staphylococcus aureus (MRSA) Prevention Initiative nationally in acute care facilities (ACFs). Since that time, numerous publications have reported declining transmission rates and infection rates due to MRSA across the VA. Recent estimates of the impact of contact precautions (CP) on transmission suggest that the infectiousness of patients while on CP was 50% lower than patients not on CP. We extend that work by estimating the variation and trend in transmission while accounting for the estimated impact of CP on transmission. Methods We analyzed ten years of data from 108 VA ACFs from 1/1/2008 – 12/31/2017 using a Bayesian transmission model. The data included admission, discharge, and surveillance and clinical test results for MRSA. Data were partitioned into five 2-year analysis periods to allow for estimates of transmission to change over time, including all facilities with complete data spanning the 10-year study period. We estimated person-to-person transmission rates for each ward assuming the classic mass-action transmission framework, while accounting for the impact of CP on transmission, and used random effect models with inverse variance weights to derive pooled estimates of the transmission rates and trends across ward-types and over time. Results In this cohort study of 108 VA hospitals during the 10-year period, more than 2 million unique individuals had over 5.6 million admissions with more than 8.4 million MRSA surveillance tests (9.3% of which were positive). We observed a decline in the overall transmission rate over time, with the reduction driven by declining rates of transmission in the ICU setting (Figure 1). We observed that the transmission rate in medical/surgical wards remained constant during the 10-year period. Transmission trend by ward Conclusion We observed that in addition to the two-fold reduction in transmission of MRSA associated with CPs, that over the study period, the transmission rate declined in VA hospitals driven largely by reductions in the ICU setting. The secular trend downward in ICUs might reflect improved hand hygiene, changes in antibiotic use, or enhancements to other infection control practices. Additional work is needed to better understand and identify these factors. Disclosures Karim Khader, PhD, BioFire Diagnostics: Grant/Research Support.