The impact of anxiety on gait impairments in Parkinson's disease: insights from sensor-based gait analysis.

BACKGROUND: Sensor-based gait analysis provides a robust quantitative tool for assessing gait impairments and their associated factors in Parkinson's disease (PD). Anxiety is observed to interfere with gait clinically, but this has been poorly investigated. Our purpose is to utilize gait analysis to uncover the effect of anxiety on gait in patients with PD. METHODS: We enrolled 38 and 106 PD patients with and without anxiety, respectively. Gait parameters were quantitively examined and compared between two groups both in single-task (ST) and dual-task (DT) walking tests. Multiple linear regression was applied to evaluate whether anxiety independently contributed to gait impairments. RESULTS: During ST, PD patients with anxiety presented significantly shorter stride length, lower gait velocity, longer stride time and stance time, longer stance phase, smaller toe-off (TO) and heel-strike (HS) angles than those without anxiety. While under DT status, the differences were diminished. Multiple linear regression analysis demonstrated that anxiety was an independent factor to a serials of gait parameters, particularly ST-TO (B = -2.599, (-4.82, -0.38)), ST-HS (B = -2.532, (-4.71, -0.35)), ST-TO-CV (B = 4.627, (1.71, 7.64)), ST-HS-CV(B = 4.597, (1.66, 7.53)), ST stance phase (B = 1.4, (0.22, 2.58)), and DT stance phase (B = 1.749, (0.56, 2.94)). CONCLUSION: Our study discovered that anxiety has a significant impact on gait impairments in PD patients, especially exacerbating shuffling steps and prolonging stance phase. These findings highlight the importance of addressing anxiety in PD precision therapy to achieve better treatment outcomes.

Multi-Level Biomarkers for Early Diagnosis of Ischaemic Stroke: A Systematic Review and Meta-Analysis.

Blood biomarkers hold potential for the early diagnosis of ischaemic stroke (IS). We aimed to evaluate the current weight of evidence and identify potential biomarkers and biological pathways for further investigation. We searched PubMed, EMBASE, the Cochrane Library and Web of Science, used R package meta4diag for diagnostic meta-analysis and applied Gene Ontology (GO) analysis to identify vital biological processes (BPs). Among 8544 studies, we included 182 articles with a total of 30,446 participants: 15675 IS, 2317 haemorrhagic stroke (HS), 1798 stroke mimics, 846 transient ischaemic attack and 9810 control subjects. There were 518 pooled biomarkers including 203 proteins, 114 genes, 108 metabolites and 88 transcripts. Our study generated two shortlists of biomarkers for future research: one with optimal diagnostic performance and another with low selection bias. Glial fibrillary acidic protein was eligible for diagnostic meta-analysis, with summary sensitivities and specificities for differentiating HS from IS between 3 h and 24 h after stroke onset ranging from 73% to 80% and 77% to 97%, respectively. GO analysis revealed the top five BPs associated with IS. This study provides a holistic view of early diagnostic biomarkers in IS. Two shortlists of biomarkers and five BPs warrant future investigation.

Evaluating the Patient Boarding during Omicron Surge in Hong Kong: Time Series Analysis.

The fifth wave of COVID-19 outbreaks in Hong Kong (HK) from January to March 2022 has the highest confirmed cases and deaths compared with previous waves. Severe hospital boarding (to inpatient wards) was noted in various Emergency Departments (EDs). Our objective is to identify factors associated with hospital boarding during Omicron surge in HK. We conducted a retrospective cohort study including all ED visits and inpatient (IP) ward admissions from January 1st to March 31st, 2022. Vector Autoregression model evaluated the effects of a single variable on the targeted hospital boarding variables. Admissions from elderly homes with 6 lag days held the highest positive value of statistical significance (t-stat = 2.827, P < .05) caused prolonged admission waiting time, while medical patients with 4 lag days had the highest statistical significance (t-stat = 2.530, P < .05) caused an increased number of boarding patients. Within one week after impulses, medical occupancy's influence on the waiting time varied from 0.289 on the 1st day to -0.315 on the 7th day. While occupancy of medical wards always positively affected blocked number of patients, and its response was maximized at 0.309 on the 2nd day. Number of confirmed COVID-19 cases was not the sole significant contributor, while occupancy of medical wards was still a critical factor associated with patient boarding. Increasing ward capacity and controlling occupancy were suggested during the outbreak. Moreover, streamlining elderly patients in ED could be an approach to relieve pressure on the healthcare system.

Oral Prednisolone in the Treatment of Acute Gout: A Pragmatic, Multicenter, Double-Blind, Randomized Trial.

BACKGROUND: Two recent double-blind, randomized, controlled trials (RCTs) showed that oral steroids and nonsteroidal anti-inflammatory drugs have similar analgesic effectiveness for management of gout, but the trials had small sample sizes and other methodological limitations. OBJECTIVE: To compare the effectiveness and safety of oral prednisolone versus oral indomethacin in patients presenting to emergency departments (EDs) with acute gout. DESIGN: Multicenter, double-blind, randomized equivalence trial. Patients were randomly assigned (1:1 ratio) to receive either indomethacin or prednisolone. (ISRCTN registry number: ISRCTN45724113). SETTING: Four EDs in Hong Kong. PARTICIPANTS: 416 patients aged 18 years or older. MEASUREMENTS: Analgesic effectiveness was defined as changes in pain (at rest or with activity) greater than 13 mm on a 100-mm visual analogue scale. Outcomes were measured during the first 2 hours in the ED and from days 1 to 14. RESULTS: 376 patients completed the study. Equivalent and clinically significant within-group reductions in mean pain score were observed with indomethacin and prednisolone in the ED (approximately 10 mm [rest] and 20 mm [activity]) and from days 1 to 14 (approximately 25 mm [rest] and 45 mm [activity]). No major adverse events occurred during the study. During the ED phase, patients in the indomethacin group had more minor adverse events than those in the prednisolone group (19% vs. 6%; P < 0.001). During days 1 to 14, 37% of patients in each group had minor adverse events. LIMITATION: Diagnosis of gout was usually based on clinical criteria rather than examination of joint fluid. CONCLUSION: Oral prednisolone and indomethacin had similar analgesic effectiveness among patients with acute gout. Prednisolone is a safe, effective first-line option for treatment of acute gout. PRIMARY FUNDING SOURCE: Health and Health Services Research Grant Committee of the Hong Kong Government.

Early Exclusion of Major Adverse Cardiac Events in Emergency Department Chest Pain Patients: A Prospective Observational Study.

BACKGROUND: The current evaluation of patients with chest pain presenting to an emergency department (ED) with suspected acute coronary syndrome (ACS) is a lengthy process involving serial measurements of troponin. OBJECTIVE: We aimed to validate the diagnostic accuracy of a Thrombolysis in Myocardial Infarction (TIMI) score with single high-sensitive cardiac troponin T (hs-cTnT) for early rule out of 30-day major adverse cardiac events (MACE), and to compare the TIMI score with combinations of heart-type fatty acid binding protein (H-FABP) and a modified HEART (history, electrocardiogram, age, risk factors, troponin) score. METHODS: We recruited 602 consecutive adult patients with chest pain and suspected ACS in the ED. Each patient had TIMI and HEART scores, and a point-of-care H-FABP test. RESULTS: MACE occurred in 42 (7.0%) patients within 30 days. A low risk for 30-day MACE was identified by a modified TIMI score of 0 in 65 (11%) patients, and by a HEART score ≤ 2 in 96 (16%) patients. No MACE occurred in these groups, giving both scores a sensitivity of 100% (95% confidence interval [CI] 91.6-100%), and specificity of 11.6% (95% CI 9.2-14.5%) and 17.1% (95% CI 14.2-20.5%), respectively. Use of combined TIMI and HEART scores improved the specificity further to 22.0% (95% CI 18.7-25.6%) without lowering sensitivity. Early H-FABP measurement > 7 µg/L had a sensitivity of 41.5% (95% CI 27.8-56.6%) and a specificity of 91.1% (95% CI 88.4-93.2%) for predicting 30-day MACE. CONCLUSIONS: A modified TIMI score of 0 or a HEART score of ≤ 2, incorporating a single hs-cTnT level, will identify patients with low risk of 30-day MACE for early discharge within 2 h of ED arrival.

Early sepsis care with the National Early Warning Score 2-guided Sepsis Hour-1 Bundle in the emergency department: hybrid type 1 effectiveness-implementation pilot stepped wedge randomised controlled trial (NEWS-1 TRIPS) protocol.

INTRODUCTION: Early sepsis treatment in the emergency department (ED) is crucial to improve patient survival. Despite international promulgation, the uptake of the Surviving Sepsis Campaign (SSC) Hour-1 Bundle (lactate measurement, blood culture, broad-spectrum antibiotics, 30 mL/kg crystalloid for hypotension/lactate ≥4 mmol/L and vasopressors for hypotension during/after fluid resuscitation within 1 hour of sepsis recognition) is low across healthcare settings. Delays in sepsis recognition and a lack of high-quality evidence hinder its implementation. We propose a novel sepsis care model (National Early Warning Score, NEWS-1 care), in which the SSC Hour-1 Bundle is triggered objectively by a high NEWS-2 (≥5). This study aims to determine the feasibility of a full-scale type 1 hybrid effectiveness-implementation trial on the NEWS-1 care in multiple EDs. METHODS AND ANALYSIS: We will conduct a pilot type 1 hybrid trial and prospectively recruit 200 patients from 4 public EDs in Hong Kong cluster randomised in a stepped wedge design over 10 months. All study sites will start with an initial period of standard care and switch in random order at 2-month intervals to the NEWS-1 care unidirectionally. The implementation evaluation will employ mixed methods guided by the Reach, Effectiveness, Adoption, Implementation and Maintenance framework, which includes qualitative and quantitative data from focus group interviews, staff survey and clinical record reviews. We will analyse the 14 feasibility outcomes as progression criteria to a full-scale trial, including trial acceptability to patients and staff, patient and staff recruitment rates, accuracy of sepsis screening, protocol adherence, accessibility to follow-up data, safety and preliminary clinical impacts of the NEWS1 care, using descriptive statistics. ETHICS AND DISSEMINATION: The institutional review boards of all study sites approved this study. This study will establish the feasibility of a full-scale hybrid trial. We will disseminate the findings through peer-reviewed publications, conference presentations and educational activities. TRIAL REGISTRATION NUMBER: NCT05731349.

Derivation and internal validation of a clinical prediction score to predict major effect or death in acute metamfetamine toxicity.

OBJECTIVE: Metamfetamine use can cause serious complications or death. We aimed to derive and internally validate a clinical prediction score to predict major effect or death in acute metamfetamine toxicity. METHODS: We performed secondary analysis of 1,225 consecutive cases reported from all local public emergency departments to the Hong Kong Poison Information Centre between 1 January 2010 and 31 December 2019. We split the entire dataset chronologically into derivation (first 70% of cases) and validation (the remaining 30% of cases) cohorts. Univariate analysis was conducted, followed by multivariable logistic regression in the derivation cohort to identify independent predictors of major effect or death. We developed a clinical prediction score based on the regression coefficients of the independent predictors in the regression model and compared its discriminatory performance with five existing early warning scores in the validation cohort. RESULTS: The MASCOT (Male, Age, Shock, Consciousness, Oxygen, Tachycardia) score was derived based on the six independent predictors: male gender (1 point), age (≥35 years, 1 point), shock (mean arterial pressure <65 mmHg, 3 points), consciousness (Glasgow Coma Scale <13, 2 points), need for supplemental oxygen (1 point), and tachycardia (pulse rate >120 beats/min, 1 point). The score ranges from 0-9, with a higher score indicating higher risk. The area under the receiver operating characteristic curve of the MASCOT score was 0.87 (95% CI 0.81-0.93) in the derivation cohort and 0.91 (95% CI 0.81-1.00) in the validation cohort, with a discriminatory performance comparable with existing scores. CONCLUSIONS: The MASCOT score enables quick risk stratification in acute metamfetamine toxicity. Further external validation is warranted before wider adoption.

Applying artificial neural network in predicting sepsis mortality in the emergency department based on clinical features and complete blood count parameters.

A complete blood count (CBC) is routinely ordered for emergency department (ED) patients with infections. Certain parameters, such as the neutrophil-to-lymphocyte ratio (NLR), might have prognostic value. We aimed to evaluate the prognostic value of the presenting CBC parameters combined with clinical variables in predicting 30-day mortality in adult ED patients with infections using an artificial neural network (ANN). We conducted a retrospective study of ED patients with infections between 17 December 2021 and 16 February 2022. Clinical variables and CBC parameters were collected from patient records, with NLR, monocyte-to-lymphocyte ratio (MLR), and platelet-to-lymphocyte ratio (PLR) calculated. We determined the discriminatory performance using the area under the receiver operating characteristic curve (AUROC) and performed a 70/30 random data split and supervised ANN machine learning. We analyzed 558 patients, of whom 144 (25.8%) had sepsis and 60 (10.8%) died at 30 days. The AUROCs of NLR, MLR, PLR, and their sum were 0.644 (95% CI 0.573-0.716), 0.555 (95% CI 0.482-0.628), 0.606 (95% CI 0.529-0.682), and 0.610 (95% CI 0.534-0.686), respectively. The ANN model based on twelve variables including clinical variables, hemoglobin, red cell distribution width, NLR, and PLR achieved an AUROC of 0.811 in the testing dataset.

Association of Molnupiravir and Nirmatrelvir-Ritonavir with preventable mortality, hospital admissions and related avoidable healthcare system cost among high-risk patients with mild to moderate COVID-19.

Background: Real-world data is currently limited on the association between oral antiviral therapy and healthcare system burden in patients with mild-to-moderate COVID-19. This study aims to evaluate the clinical and cost effectiveness of Molnupiravir and Nirmatrelvir-ritonavir use in reducing mortality in this population. Methods: This is a retrospective cohort study involving 54,355 COVID-19 patients during February 22-March 31,2022 in Hong Kong. Inverse probability of treatment weighting (IPTW) was used to adjust patient characteristics. Our exposure of interest was Molnupiravir/Nirmatrelvir-Ritonavir prescription, with all-cause mortality as the primary outcome. IPTW-adjusted multivariate regressions were used to estimate treatment impact on clinic re-attendance and unplanned admissions. Finally, attributed cost and incremental cost-effectiveness ratios (ICER) were estimated. Findings: In the outpatient cohort (N = 33,217, 61.1%), 16.1% used Molnupiravir and 13.4% used Nirmatrelvir-Ritonavir, while in the inpatient cohort (N = 21,138, 38.9%), 3.8% used Molnupiravir and 1.3% used Nirmatrelvir-Ritonavir. IPTW-adjusted Cox model estimated that Molnupiravir (hazard ratio (HR)(95%CI)=0.31 (0.24-0.40), P< 0.0001) and Nirmatrelvir-Ritonavir (HR=0.10 (95%CI 0.05-0.21), P< 0.0001) were significantly associated with a reduced mortality hazard. In the outpatient cohort, both antiviral prescriptions were associated with reduced odds for unplanned hospital admissions (Molnupiravir: odds ratio (OR) =0.72 (0.52-0.98), P=0.039; Nirmatrelvir-Ritonavir: OR=0.37 (0.23-0.60), P<0.0001). Among hospitalised patients, both antiviral prescriptions were associated with significant reductions in the odds ratios for 28-days readmission (Molnupiravir: OR=0.71 (0.52-0.97), P=0.031; Nirmatrelvir-Ritonavir: OR=0.47 (0.24-0.93), P=0.030). ICERs for death averted for Molnupiravir stood at USD493,345.09 in outpatient settings and USD2,629.08 in inpatient settings. In outpatient settings, Nirmatrelvir-ritonavir cost USD331,105.27 to avert one death, but saved USD5,502.53 to avert one death in comparison with standard care. Interpretation: In high-risk patients in Hong Kong with mild-to-moderate COVID-19, Molnupiravir and Nirmatrelvir-Ritonavir prescriptions were associated with reduced all-cause mortality and significant cost savings. Funding: Centre for Health Systems & Policy Research is funded by The Tung's Foundation; and The Laboratory of Data Discovery for Health Limited(D24H) is funded the AIR@InnoHK platform administered by the Innovation and Technology Commission of Hong Kong. Funders did not have any role in study design, data collection, data analysis, interpretation and writing of this manuscript.

Association of Molnupiravir and Nirmatrelvir-Ritonavir with reduced mortality and sepsis in hospitalized omicron patients: a territory-wide study.

This study evaluates the association between antivirals (Molnupiravir and Nirmatrelvir-Ritonavir) and all-cause and respiratory mortality and organ dysfunction among high-risk COVID-19 patients during an Omicron outbreak. Two cohorts, Nirmatrelvir-Ritonavir versus control and Molnupiravir versus control, were constructed with inverse probability treatment weighting to balance baseline characteristics. Cox proportional hazards models evaluated the association of their use with all-cause mortality, respiratory mortality, and all-cause sepsis (a composite of circulatory shock, respiratory failure, acute liver injury, coagulopathy, and acute liver impairment). Patients recruited were hospitalized and diagnosed with the COVID-19 Omicron variant between February 22, 2022 and April 15, 2022, and followed up until May 15, 2022. The study included 17,704 patients. There were 4.67 and 22.7 total mortalities per 1000 person-days in the Nirmatrelvir-Ritonavir and control groups respectively before adjustment (weighted incidence rate ratio, - 18.1 [95% CI - 23.0 to - 13.2]; hazard ratio, 0.18 [95% CI, 0.11-0.29]). There were 6.64 and 25.9 total mortalities per 1000 person-days in the Molnupiravir and control groups respectively before adjustment (weighted incidence rate ratio per 1000 person-days, - 19.3 [95% CI - 22.6 to - 15.9]; hazard ratio, 0.23 [95% CI 0.18-0.30]). In all-cause sepsis, there were 13.7 and 35.4 organ dysfunction events per 1000 person-days in the Nirmatrelvir-Ritonavir and control groups respectively before adjustment (weighted incidence rate ratio per 1000 person-days, - 21.7 [95% CI - 26.3 to - 17.1]; hazard ratio, 0.44 [95% CI 0.38-0.52]). There were 23.7 and 40.8 organ dysfunction events in the Molnupiravir and control groups respectively before adjustment (weighted incidence ratio per 1000 person-days, - 17.1 [95% CI, - 20.6 to - 13.6]; hazard ratio, 0.63 [95% CI 0.58-0.69]). Among COVID-19 hospitalized patients, use of either Nirmatrelvir-Ritonavir or Molnupiravir compared with no antiviral use was associated with a significantly lower incidence of 28-days all-cause and respiratory mortality and sepsis.

Seizure as the clinical presentation of massive pulmonary embolism: Case report and literature review.

Massive pulmonary embolism (MPE) is a high-risk medical emergency. Seizure as the clinical presentation of MPE is extremely rare, and to our knowledge, there have been no reports on successful percutaneous, catheter-based treatment of MPE presenting with new-onset seizures and cardiac arrest. In this report, we discuss the case of a 64-year-old woman who presented with an episode of seizure that lasted 5 h. Seizure occurred four times within 12 h after arrival at the hospital, and in the end, she sustained a cardiac arrest. The patient had no past history of seizure or cardiopulmonary disease. Bilateral MPE was detected by a computed tomography pulmonary angiogram, and she was successfully treated with percutaneous, catheter-directed anticoagulant therapy. Pulmonary embolism-related seizures are more difficult to diagnose and have higher mortality rates than seizures. MPE should be suspected in patients presenting with new-onset seizures and hemodynamic instability.

An Occupational Therapy Fall Reduction Home Visit Program for Community-Dwelling Older Adults in Hong Kong After an Emergency Department Visit for a Fall.

OBJECTIVES: To investigate the effects of an occupational therapy fall reduction home visit program for older adults admitted to the emergency department (ED) for a fall and discharged directly home. DESIGN: Single-blind, multicenter, randomized, controlled trial. SETTINGS: EDs in three acute care hospitals in Hong Kong. PARTICIPANTS: Individuals aged 65 and older who had fallen (N = 311). INTERVENTIONS: After screening for eligibility, 204 consenting individuals were randomly assigned to an intervention group (IG) and received a single home visit from an occupational therapist (OT) within 2 weeks after discharge from the hospital or a control group (CG) and received a well-wishing visit from a research assistant not trained in fall prevention. MEASUREMENTS: Both groups were followed for 12 months through telephone calls made every 2 weeks by blinded assessors with a focus on the frequency of falls. Another blinded assessor followed up on their status with telephone calls 4, 8, and 12 months after ED discharge. Prospective fall records on hospital admissions were retrieved from electronic databases; 198 individuals were followed for 1 year on an intention-to-treat basis. RESULTS: The percentage of fallers over 1 year was 13.7% in the IG (n = 95) and 20.4% in the CG (n = 103). There were significant differences in the number of fallers (P = .03) and the number of falls (P = .02) between the two groups over 6 months. Significant differences were found in survival analysis for first fall at 6 months (log-rank test 5.052, P = .02) but not 9 or 12 months. CONCLUSION: One OT visit after a fall was more effective than a well-wishing visit at reducing future falls at 6 months. A booster OT visit at 6 months is suggested.

Paraoxonase 1 gene Q192R polymorphism affects stroke and myocardial infarction risk.

OBJECTIVES: Paraoxonase (PON1), an enzyme associated with high-density lipoprotein (HDL) particles, inhibits oxidation and atherogenesis. We sought to investigate the association of the PON1 Q192R polymorphism with stroke and heart disease. DESIGN AND METHODS: In a case control study, we genotyped 242 ischemic stroke, 231 myocardial infarction (MI), and 310 healthy control subjects, all Chinese. RESULTS: R-containing genotypes (R+) were associated with vascular disease, OR = 1.5, P = 0.03. RR was increased in MI patients who were either smokers (OR = 3.1, P = 0.01), male, or younger than 60. R+ but not RR genotypes were increased in stroke patients, particularly large artery type (OR = 2.6 and P = 0.02 for R+, OR = 1.0 for RR) or among smokers. The relative dearth of RR in stroke might be due to earlier MI or death in at-risk people, such as smokers. R+ genotypes were increased with stroke in hypertensive (OR = 2.1, P = 0.02) but not normotensive (OR = 1.0) subjects. CONCLUSIONS: PON1 192R+ genotypes were associated with stroke and MI, particularly in subsets of patients, in patterns suggesting a possible survivor effect.

Plasma miR-124-3p and miR-16 concentrations as prognostic markers in acute stroke.

OBJECTIVES: This study aimed to investigate plasma concentrations of miR-124-3p and miR-16 as prognostic markers in emergency department patients with acute stroke. DESIGN AND METHODS: Plasma concentrations of miR-124-3p and miR-16 of 84 stroke patients (presenting to the emergency department within 24h from onset of symptoms) were determined by RT-qPCR. The primary outcome measure was 3-month mortality and the secondary outcome measure was post-stroke modified Rankin Score (mRS). RESULTS: Twelve patients (14.3%) died within 3months of hospital admission and forty-one (48.8%) patients as achieved a 3-month mRS>2. Median plasma miR-124-3p concentrations were elevated in patients who died compared to patients who survived (p=0.0052), and its levels were found to be higher in patients with a 3-month mRS>2 compared with patients with mRS≤2 (p=0.0312). Higher plasma miR-16 concentrations were observed in patients who survived than in patients who died (p=0.0394), while its concentrations were lower in patients achieving mRS>2 than in patients with mRS≤2 (p=0.0124). For a subgroup of cases presenting to the emergency department within 6h from time of symptom onset (n=36), plasma miR-124-3p concentrations predicted 3-month mortality with an area under the ROC curve of 0.87 (95%CI: 0.72-0.96). CONCLUSIONS: Plasma miR-124-3p and miR-16 are molecular markers which could be useful for the early prediction of mortality and mRS.

Assessment of hyperacute stroke like symptoms by diffusion-weighted images.

We assessed the role of diffusion-weighted images in the evaluation of hyperacute stroke like symptoms in 18 patients. The volume of infarct measured by diffusion-weighted imaging (DWI) was correlated with the later computed tomography (CT) examinations. DWI had a sensitivity of 92%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 86% in detection of acute hemorrhagic and ischemic stroke. There is a good correlation with the volume of infarct measured by DWI and follow-up CT with a P < .05.

Hemodynamic measurements for evaluating vasovagal syncope in the emergency department.

Syncope is a sudden and transient loss of consciousness and postural tone, with spontaneous recovery without medical intervention. It accounts for 1.0% to 1.5% of emergency department (ED) visits and up to 6% of hospital admissions. Vasovagal syncope may be the cause of syncope in 21% to 40% of cases. A 53-year-old Chinese woman was brought to the ED by ambulance after a near-syncope episode while performing gentle morning exercises. She was hypotensive and bradycardic in the ambulance. Upon arrival at the ED, her blood pressure was 89/61 mmHg. The use of a Doppler cardiac output monitor readily demonstrated that the patient's systemic vascular resistance was reduced, with cardiac output at the lower limit of the normal range. These hemodynamic data were useful in supporting the diagnosis of vasovagal syncope; they helped in the risk stratification of our patient with syncope, and guided the management and subsequent disposition decision.

Predictors of positive stool culture in adult patients with acute infectious diarrhea.

Stool cultures for bacterial pathogens are often requested for investigation of patients with infectious diarrhea, but the literature reports low yield for this diagnostic test. The identification of clinical predictors of positive stool culture will help the physician in determining the necessity for stool requests. A retrospective study was performed in the setting of an Emergency Department (ED) in Hong Kong, to compare presenting features of adult patients with positive stool culture against those with negative culture. We compared 130 consecutive cases with positive stool culture, over a 12-month period, against 119 control cases obtained from a random sampling of 524 consecutive negative cases over the same period. In multivariate analysis, the independent variables found to be associated with positive stool culture were: the month of presentation (summer season), fever, duration of abdominal pain, and requirement of IV fluid therapy. Neither bloody diarrhea nor persistent diarrhea was associated with positive stool culture.