Neutrophil­to­lymphocyte ratio reflects lung injury in thoracic radiotherapy and immune checkpoint inhibitors combination therapy with different sequences.

The combination of thoracic radiotherapy and immune checkpoint inhibitors (ICIs) has emerged as a novel treatment approach for malignant tumors. However, it is important to consider the potential exacerbation of lung injury associated with this treatment modality. The neutrophil-to-lymphocyte ratio (NLR), an inflammatory marker, holds promise as a non-invasive indicator for assessing the toxicity of this combination therapy. To investigate this further, a study involving 80 patients who underwent thoracic radiotherapy in conjunction with ICIs was conducted. These patients were divided into two groups: The concurrent therapy group and the sequential therapy group. A logistic regression analysis was conducted to ascertain risk factors for grade ≥2 pneumonitis. Following propensity score matching, the NLR values were examined between the concurrent group and the sequential group to evaluate any disparity. A mouse model of radiation pneumonitis was established, and ICIs were administered at varying time points. The morphological evaluation of lung injury was conducted using H&E staining, while the NLR values of peripheral blood were detected through flow cytometry. Logistic regression analysis revealed that radiation dosimetric parameters (mean lung dose, total dose and V20), the inflammatory index NLR at the onset of pneumonitis, and treatment sequences (concurrent or sequential) were identified as independent predictors of grade ≥2 treatment-related pneumonitis. The results of the morphological evaluation indicated that the severity of lung tissue injury was greater in cases where programmed cell death protein 1 (PD-1) blockade was administered during thoracic radiotherapy, compared with cases where PD-1 blockade was administered 14 days after radiotherapy. Moreover, the present study demonstrated that the non-invasive indicator known as the NLR has the potential to accurately reflect the aforementioned injury.

Prognostic value of neuron-specific enolase in patients with advanced and metastatic non-neuroendocrine non-small cell lung cancer.

BACKGROUND: Increased serum neuron-specific enolase (NSE) level was found in a substantial proportion (30-69%) of patients with non-small-cell lung cancer (NSCLC), but little was known about the clinical properties of NSE in NSCLC. OBJECTIVE: We aimed to assess the level of serum NSE to predict prognosis and treatment response in patients with advanced or metastatic non-neuroendocrine NSCLC. METHODS: We retrospectively analyzed 363 patients with advanced and metastatic NSCLC between January 2011 and October 2016. The serum NSE level was measured before initiation of treatment. RESULTS: Patients with high NSE level (≥26.1 ng/ml) showed significantly shorter progression-free survival (PFS) (5.69 vs 8.09 months; P=0.02) and significantly shorter overall survival (OS) than patients with low NSE level (11.41 vs 24.31 months; P=0.01). NSE level was an independent prognostic factor for short PFS (univariate analysis, hazard ratio [HR] = 2.40 (1.71-3.38), P<0.001; multivariate analysis, [HR] = 1.81 (1.28-2.56), P=0.001) and OS (univariate analysis, [HR] = 2.40 (1.71-3.37), P<0.001; multivariate analysis, [HR] = 1.76 (1.24-2.50), P=0.002). CONCLUSION: The survival of NSCLC patients with high serum NSE level was shorter than that of NSCLC patients with low serum NSE levels. Serum NSE level was a predictor of treatment response and an independent prognostic factor.

Assessment of safety margin after microwave ablation of stage I NSCLC with three-dimensional reconstruction technique using CT imaging.

OBJECTIVE: To assess the ablative margin of microwave ablation (MWA) for stage I non-small cell lung cancer (NSCLC) using a three-dimensional (3D) reconstruction technique. MATERIALS AND METHODS: We retrospectively analyzed 36 patients with stage I NSCLC lesions undergoing MWA and analyzed the relationship between minimal ablative margin and the local tumor progression (LTP) interval, the distant metastasis interval and disease-free survival (DFS). The minimal ablative margin was measured using the fusion of 3D computed tomography reconstruction technique. RESULTS: Univariate and multivariate analyses indicated that tumor size (hazard ratio [HR] = 1.91, P < 0.01; HR = 2.41, P = 0.01) and minimal ablative margin (HR = 0.13, P < 0.01; HR = 0.11, P < 0.01) were independent prognostic factors for the LTP interval. Tumor size (HR = 1.96, P < 0.01; HR = 2.35, P < 0.01) and minimal ablative margin (HR = 0.17, P < 0.01; HR = 0.13, P < 0.01) were independent prognostic factors for DFS by univariate and multivariate analyses. In the group with a minimal ablative margin < 5 mm, the 1-year and 2-year local progression-free rates were 35.7% and 15.9%, respectively. The 1-year and 2-year distant metastasis-free rates were 75.6% and 75.6%, respectively; the 1-year and 2-year disease-free survival rates were 16.7% and 11.1%, respectively. In the group with a minimal ablative margin ≥ 5 mm, the 1-year and 2-year local progression-free rates were 88.9% and 69.4%, respectively. The 1-year and 2-year distant metastasis-free rates were 94.4% and 86.6%, respectively; the 1-year and 2-year disease-free survival rates were 88.9% and 63.7%, respectively. The feasibility of 3D quantitative analysis of the ablative margins after MWA for NSCLC has been validated. CONCLUSIONS: The minimal ablative margin is an independent factor of NSCLC relapse after MWA, and the fusion of 3D reconstruction technique can feasibly assess the minimal ablative margin.

Obesity and Pregnancy.

The worldwide rates of obesity have increased significantly in recent decades. In the United States, more than 50% of pregnant women are overweight or obese. Obese gravid women are more prone to adverse pregnancy outcomes, including gestational diabetes, hypertensive disorders, and cardiovascular diseases. The adverse outcomes extend beyond the pregnant obese woman; offspring of obese women are themselves at increased risk of prematurity, fetal death, injury during birth, and transient respiratory problems and metabolic effects (ie, neonatal hypoglycemia). Furthermore, maternal obesity can predispose their offspring to long-term health problems, potentially generating an intergenerational cycle of obesity and insulin resistance.

Hypervolemic Hyponatremia as a Reversible Cause of Cardiopulmonary Arrest in a Postpartum Patient with Preeclampsia.

Although the incidence of preeclampsia complicated by hyponatremia is reportedly rare, the effects on the maternal outcome are severe and life-threatening. Here, we describe a case of a patient with preeclampsia who coded postpartum and was discovered to have hypervolemic hyponatremia and subsequently recovered after fluid diuresis and resolution of hyponatremia. While hyponatremia in preeclampsia is rare, it is even more unique for it to lead to cardiopulmonary arrest consequently. Therefore, sodium levels and fluid status should be monitored closely and promptly corrected without delay to prevent cardiopulmonary arrest in patients with preeclampsia.

Vaginal host immune-microbiome interactions in a cohort of primarily African-American women who ultimately underwent spontaneous preterm birth or delivered at term.

BACKGROUND: Recent studies suggest that alterations in the vaginal microbiome allow for the assessment of the risk for spontaneous preterm birth (PTB), the leading cause of neonatal morbidity and mortality worldwide. However, the associations between the local immune response and the vaginal microbiome are still poorly understood. Herein, we characterize the vaginal host immune-microbiome interactions in women who ultimately underwent PTB and in those who delivered at term. METHODS: Vaginal fluid samples from 52 pregnant women (of whom 18 underwent PTB and 34 delivered at term) were collected between 10 and 32 weeks of gestation in a case-control study. Concentrations of 33 immune mediators were determined using sensitive and specific immunoassays. The previously published 16S rRNA gene sequence and bacterial phylotype data of these subjects were utilized in this study. Linear mixed effects models were utilized to test associations between vaginal immune mediator concentrations and bacterial phylotype relative abundances. RESULTS: 1) In the overall study population, vaginal concentrations of CXCL10, CCL2, CCL3, SLP1 and VEGF negatively correlated with non-Lactobacillus, Community State Type IV (CST IV) members of the vaginal microbiome; 2) CXCL10, in particular, negatively correlated with 15 bacterial phylotypes, most of which are typical members of CST IV, such as Gardnerella vaginalis, Megasphaera spp., and Atopobium vaginae; 3) Gemella spp., also members of CST IV, negatively correlated with vaginal concentrations of VEGF, CCL2, CCL3, SLPI, and CXCL10; 4) when comparing PTB cases to term controls, five soluble immune mediators (CCL26, CCL22, CCL2, CXCL10, and IL-16), especially CCL26, were negatively correlated with five typical members of CST IV: Sneathia sanguinegens, Parvimonas micra, Veillonellaceae, BVAB2, and Gemella spp.; and 5) Sneathia sanguinegens had stronger negative associations with all five soluble immune mediators (CCL26, CCL22, CCL2, CXCL10, and IL-16) in PTB cases than in term controls. CONCLUSIONS: The assessment of vaginal host immune-microbiome interactions revealed that specific soluble immune mediators, mainly CXCL10, negatively correlated with typical members of CST IV of the vaginal microbiome. Sneathia sanguinegens, in particular, had stronger negative associations with different immune mediators, including CXCL10 and CCL26, in women who ultimately underwent PTB compared to those who delivered at term. These findings provide insight into the vaginal host immune-microbiome interactions in normal and complicated pregnancies.

Cellular immune responses in amniotic fluid of women with a sonographic short cervix.

Objectives A sonographic short cervix is one of the strongest predictors of preterm delivery. However, the cellular immune composition of amniotic fluid in women with a short cervix has not yet been described. Herein, we determined cellular and soluble immune responses in amniotic fluid from pregnant women with a mid-trimester asymptomatic short cervix. Methods Amniotic fluid samples (n=77) were collected from asymptomatic women with a cervical length between 15 and 25 mm (n=36, short cervix) or ≤15 mm (n=41, severely short cervix) diagnosed by ultrasound. Flow cytometry and multiplex measurement of cytokines/chemokines were performed. Results (1) The cellular immune composition of amniotic fluid did not differ between women with a severely short cervix (≤15 mm) and those with a short cervix 15-25 mm; (2) amniotic fluid concentrations of multiple cytokines/chemokines were higher in women with a severely short cervix (≤15 mm) than in those with a short cervix 15-25 mm; (3) the cellular immune composition of amniotic fluid did not differ between women with a severely short cervix (≤15 mm) who ultimately underwent preterm delivery and those who delivered at term; and (4) amniotic fluid concentrations of IL-2, but not other immune mediators, were increased in women with a severely short cervix (≤15 mm) who ultimately delivered preterm compared to those who delivered at term. Conclusions Women with a severely short cervix (≤15 mm) have increased concentrations of pro-inflammatory mediators in the amniotic cavity; yet, these do not translate to changes in the cellular immune response.

From SARS to Avian Influenza Preparedness in Hong Kong.

The first human H5N1 case was diagnosed in Hong Kong in 1997. Since then, experience in effective preparedness strategies that target novel influenza viruses has expanded. Here, we report on avian influenza preparedness in public hospitals in Hong Kong to illustrate policies and practices associated with control of emerging infectious diseases. The Hong Kong government's risk-based preparedness plan for influenza pandemics includes 3 response levels for command, control, and coordination frameworks for territory-wide responses. The tiered levels of alert, serious, and emergency response enable early detection based on epidemiological exposure followed by initiation of a care bundle. Information technology, laboratory preparedness, clinical and public health management, and infection control preparedness provide a comprehensive and generalizable preparedness plan for emerging infectious diseases.

Effect and mechanism of peroxisome proliferator-activated receptor-γ on the drug resistance of the U-87 MG/CDDP human malignant glioma cell line.

Peroxisome proliferator-activated receptor-γ (PPAR-γ) is important in tumor differentiation, proliferation and apoptosis. However, the effect and mechanism of PPAR-γ on the promotion of cisplatin sensitivity in glioma cells remain to be elucidated. The present study established cisplatin-resistant U-87 MG/CDDP cell lines and U-87 MG/CDDP cell lines overexpressing PPAR-γ. With upregulated expression of PPAR-γ, the sensitivity of cancer cells to cisplatin was increased. Flow cytometry revealed that the intracellular content of rhodamine-123 was increased, expression of P-glycoprotein was downregulated, cell cycle was arrested in G0/G1 phase, apoptosis and oxidative stress was increased, levels of intracellular thymidylate synthase, glutathione and transforming growth factor-ß1 were decreased, expression levels of multidrug resistance related gene (MDR), multidrug resistance-associated protein and glutothionine S-transferase-π were downregulated, expression levels of cell proliferation and apoptosis associated genes, including survivin and B-cell lymphoma-2, were downregulated, p53, p21 and caspase-3/8 were significantly upregulated, phosphorylation of extracellular signal-regulated kinase and small mothers against decapentaplegic 2 were downregulated, and the transcriptional activities of Twist and nuclear factor (erythroid-derived 2)-like 2 were significantly reduced. The results suggested that upregulation of PPAR-γ in the U-87 MG/DDP cells increased cisplatin sensitivity, and the underlying mechanisms included the regulation of MDR and apoptosis associated genes, which increased the intracellular accumulation of the drug, inhibited cell proliferation and promoted cell apoptosis.

Advantages of CyberKnife for inoperable stage I peripheral non-small-cell lung cancer compared to three-dimensional conformal radiotherapy.

This study was conducted to compare the clinical curative effect and acute radiation lung reactions between CyberKnife (CK) and three-dimensional conformal radiotherapy (3DCRT) treatment for inoperable stage I peripheral non-small-cell lung cancer (NSCLC). We retrospectively analyzed 68 patients with inoperable stage I peripheral NSCLC between 2012 and 2013 in our institution. The CK patients were treated with 42-60 Gy in three fractions, while the 3DCRT patients were treated with a total of 60 Gy, at 2 Gy per fraction. The patients were followed up and the clinical outcome was evaluated according to the Response Evaluation Criteria in Solid Tumours. We assessed the presence of acute radiation pneumonitis and pulmonary function status by thoracic scan and pulmonary function tests following CK and 3DCRT treatment. The binary univariate logistic regression analysis demonstrated that treatment method and forced expiratory volume in 1 sec/forced vital capacity (FEV1/FVC) prior to treatment (pre-FEV1/FVC) were the main factors affecting the risk of radiation pneumonitis. The analysis of these factors through multivariate logistic regression method demonstrated that treatment method for grade 1 and 2 [odds ratio (OR)= 7.866 and 11.334, respectively) and pre-FEV1/FVC for grade 1, 2 and 3 (OR = 5.062, 11.498 and 15.042, respectively) were significant factors affecting the risk of radiation pneumonitis (P<0.05). The 68 patients were divided into two subgroups using the threshold of pre-FEV1/FVC selected by the receiver operating characteristic curve. There were significant differences between the 3DCRT and CK treatment in both the pre-FEV1/FVC <68% and ≥68% subgroups for radiation pneumonitis (P=0.023 and 0.002, respectively). There was no statistically significant change in FVC, FEV1 and carbon monoxide diffusion capacity (DCLO) in the CK group, whereas there was a decrease in DCLO in the 3DCRT group. The complete remission rate was 40 vs. 34.2% at 1 year in the CK and 3DCRT groups, respectively. In conclusion, in this cohort of patients with inoperable stage I peripheral NSCLC, CK appears to be a safe and superior alternative to conventionally fractionated radiotherapy.

Prognostic value of FDG uptake in primary inoperable non-small cell lung cancer.

The purpose of this study was to assess the prognostic value of 18F-fluoro-2-deoxy-glucose positron emission tomography (FDG-PET) in therapy for non-small cell lung cancer (NSCLC) and to further analyze the possible risk factors contributing to overall survival (OS) and progression-free survival (PFS). We retrospectively analyzed fifty patients between June 2007 and June 2010 with NSCLC who underwent positron emission tomography/computed tomography. We examined the correlation of the maximum standardized uptake value (SUVmax) in FDG-PET of the primary tumor with other possible factors. The FDG uptake in the primary tumor was also compared for the different Union for International Cancer Control (UICC) staging groups and further correlation was analyzed. We divided the patients into two groups by the receiver operating characteristic curve of SUVmax: SUVmax < 5.45 (low-SUV) and ≥ 5.45 (high-SUV). The prognostic value of each parameter for OS and PFS was determined by using univariate and multivariate analysis. There were significant correlations between SUVmax and Tumor length, N stage, UICC stage, histologic differentiation (r = 0.298, 0.855, 0.345, 0.435). The comparison between the low- and high-SUV groups was evaluated. Statistically significant differences were found in the SUVmax of the primary tumors among different UICC staging groups, and the correlation between stages I-II and stages III-IV for OS and PFS was also statistically significant. Univariate analysis showed that performance status (PS-ZPS score), histologic differentiation, UICC stages, and SUVmax of the primary tumor were significantly associated with OS and PFS. Multivariate logistic analysis showed that histologic differentiation and SUVmax of primary tumor might be considered as significant predictive factors for OS and PFS in patients with NSCLC. Our results showed that there was a significant relationship between the SUVmax of the primary tumor and OS and PFS. FDG uptake by the primary tumor may be an independent outcome predictor for patients with NSCLC.

A study on the effect of aqueous extract of Lobelia chinensis on colon precancerous lesions in rats.

This paper studies the effects of Lobelia chinensis on colon precancerous lesions and on colonic epithelial proliferation and apoptosis in DMH-induced rats. After two weeks of feeding, 50 Wistar rats were randomly divided into five groups, namely the normal group, model group, Lobelia chinensis low-dose group, medium-dose group and high-dose group. Lobelia chinensis was made into ACF model, and administered to experimental groups for 10 consecutive weeks. Control group was given equivalent amount of normal saline. After feeding for 10 weeks, the rats in each group were sacrificed and the changes in colonic ACF number of rats in experimental groups were observed, and the inhibition rates were calculated. The results showed that among the rats fed for 24 h and 48 h, the number of apoptotic cells in colonic crypts of rats in DMH group did not differ significantly from the control group, while the difference was obvious between the control group and Lobelia chinensis treatment groups. The medium and high doses, that is, 0.45 g/kg and 1.35 g/kg can significantly inhibit ACF formation (P<0.01). The inhibition rates of low, medium and high doses were 8.12%, 59.42% and 65.44%, respectively.

Reliability of acuities determined with the sweep visual evoked potential (sVEP).

sVEPs are generally used to rapidly obtain visual acuity. Several studies have determined the reliability of acuity measurements with psychophysical techniques. The aim of this study was to determine the intersession and intrasession variabilities of sVEP measurements. Twenty-four normal, adult subjects took part in this project. Stimulus production and data analyses were done using an Enfant 4010. Standard VEP recording techniques were employed. Data were collected on two separate days (at least 1 week apart). At each visit, two complete sets of sVEP data were collected and averaged. A logMAR acuity chart was also used to determine the acuity at each visit. Paired t tests, 95% confidence intervals, intraclass correlation coefficients, and coefficients of repeatability were used to determine whether there was a difference in the intrasession and intersession acuities. The mean acuity difference and coefficient of repeatability were +0.01 and 0.191 for visit 1 and -0.019 and 0.186 for visit 2, respectively. The mean acuity difference and coefficient of repeatability across visits were +0.008 and 0.176 for the first acuity and-0.02 and 0.170 for the second acuity, respectively. Paired t tests did not find a significant difference between any set of data or the average for visits one and two (all P values > 0.05). The intraclass correlation coefficients comparing the average sVEP data and the logMAR data for visits 1 and 2 were 0.71 and 0.88, respectively. The coefficients of repeatability for the averaged sVEP acuity and the logMAR acuity for the two visits were 0.11 and 0.07, respectively. The repeatability of the sVEP acuity estimate in a large population of adults is similar to that of previous published reports on infants and is nearly as high as that of logMAR acuity chart data. The repeatability is the same for single best estimates of acuity and averaged estimates of acuity across visits.

ERGs and psychophysical thresholds in students with reading discomfort.

PURPOSE: Symptoms of reading discomfort include unpleasant somatic and perceptual effects, such as eye-strain, headache, and blurred text, despite normal visual acuity. Reading discomfort has been proposed to be the result of increased noise in the visual system. Several studies have suggested that the symptoms can be minimized by having the subject wear colored filters. Thus, there may be abnormal neural processing in the cone pathways. This study measured L- and M-cone isolating (1) ERGs and (2) psychophysical thresholds in normal and reading discomfort subjects to determine if cone processing was abnormal in the reading discomfort population. METHODS: Twenty-two normal and nineteen reading discomfort college students took part in this study. The normal subjects had Conlon survey scores within 0.5 SD of the mean and the reading discomfort subjects had scores >1.5 SD above the mean. ERGs were determined for a range (5 to 15%) of L- and M-cone contrasts. Slopes were determined for the L- and M-cone ERG amplitudes for each subject. Psychophysical thresholds were determined with a 2AFC technique combined with a 3-up and 1-down staircase procedure that terminated after 18 reversals occurred. The threshold was calculated as the average of the last 8 reversals. RESULTS: The average ERG slopes were not significantly different between the normal and reading discomfort groups (L-Cone, p = 0.086; M-Cone, p = 0.47). The L/M cone ratios for the slopes were not significantly different (p = 0.55). The log of the color contrast thresholds were not significantly different between the normal and reading discomfort groups (L-Cone, p = 0.97; M-Cone, p = 0.92). CONCLUSIONS: L- and M- cone ERG contrast gains and psychophysical estimates of color contrast thresholds were not significantly different. These results do not support the noisy visual system hypothesis of reading discomfort.

A territory-wide electronic health record--from concept to practicality: the Hong Kong experience.

In Hong Kong, a pilot project is being undertaken to implement a web-based electronic patient record system to allow integrated, real time patient based information to be shared in clinics, private and public hospitals. Such sharing aims to ensure that complete and accurate healthcare information is available to citizens' multiple points of care through a stable IT system. A challenge is to share this electronic information whilst ensuring privacy and security. Hong Kong has achieved its initial goals and pioneered in building a territory-wide electronic health record (EHR). This paper will outline the tasks involved, approach, method used and initial review of the pilot project. Barriers to implementation are discussed and critical success factors are identified.

Principles-based medical informatics for success--how Hong Kong built one of the world's largest integrated longitudinal electronic patient records.

Since 1994, the Hospital Authority has been developing and deploying clinical applications at its constituent 41 hospitals and 121 clinics. The Clinical Management System (CMS) is now used by over 4000 doctors and 20000 other clinicians on a daily basis to order, document and review care. The territory-wide Electronic Patient Record (ePR) has given clinicians an integrated, longitudinal, lifelong view of a patient's record. Today the CMS and ePR form an essential clinical and management tool to the Hospital Authority. The CMS handles two million clinical transactions per day, and the ePR has over 6TB of data covering 57 million episodes for 7.9 million patients. This paper describes how the HA has taken a principles-based approach to Medical Informatics to achieve its success in the enterprise-wide deployment and deep utilization of a comprehensive clinical information system.

Building a womb-to-tomb health record in Hong Kong--an application of information architecture.

The Hospital Authority developed the Information Architecture (IA) model in 2002 to support a fast, robust, flexible and accurate electronic patient record (ePR) to meet the high-tempo health care environment in Hong Kong. With several successful applications in sharing data that were created for the same patients in various systems, the IA model was further developed to extend the longitudinal ePR to include one's fetal data as entered in the mother's record. This paper describes how various IA elements: Section, View, Form, Group, Entity, Content, Document supports the building of a true womb-to-tomb ePR for the HA patients. The future focus of Information Architecture in the HA will include building a Information Architecture Management System and linking the ePR with other patient records in the community.

A clinical prediction rule for diagnosing severe acute respiratory syndrome in the emergency department.

BACKGROUND: Accurate, objective models of triage for patients with suspected severe acute respiratory syndrome (SARS) could assess risks and improve decisions about isolation and inpatient treatment. OBJECTIVE: To develop and validate a clinical prediction rule for identifying patients with SARS in an emergency department setting. DESIGN: Retrospective analysis using a 2-step coefficient-based multivariable logistic regression scoring method with internal validation by bootstrapping. SETTING: 2 hospitals in Hong Kong. PARTICIPANTS: 1274 consecutive patients from 1 hospital and 1375 consecutive patients from another hospital. MEASUREMENTS: Points were assigned on the basis of history, physical examination, and simple investigations obtained at presentation. The outcome measure was a final diagnosis of SARS, as confirmed by World Health Organization laboratory criteria. RESULTS: Predictors for SARS on the basis of history (step 1) included previous contact with a patient with SARS and the presence of fever, myalgia, and malaise. Age 65 years and older and younger than 18 years and the presence of sputum, abdominal pain, sore throat, and rhinorrhea were inversely related to having SARS. In step 2, haziness or pneumonic consolidation on chest radiographs and low lymphocyte and platelet counts, in addition to a positive contact history and fever were associated with a higher probability of SARS. A high neutrophil count, the extremes of age, and sputum production were associated with a lower probability of SARS. In the derivation sample, the observed incidence of SARS was 4.4% for those assigned to the low-risk group (in steps 1 or 2); in the high-risk group, incidence of SARS was 21.0% for quartile 1, 39.5% for quartile 2, 61.2% for quartile 3, and 79.7% for quartile 4. This prediction rule achieved an optimism-corrected sensitivity of 0.90, a specificity of 0.62, and an area under the receiver-operating characteristic curve of 0.85. LIMITATIONS: The prediction rule may not apply to isolated cases occurring during an interepidemic period. Generalizability of the findings should be confirmed in other SARS-affected countries and should be prospectively validated if SARS returns. CONCLUSIONS: Our findings suggest that a simple model that uses clinical data at the time of presentation to an emergency department during an acute outbreak predicted the incidence of SARS and provided good diagnostic utility.