Correspondence / American Journal of Emergency Medicine 33 (2015) 290–304
Vareena Laohaphan, MD Department of Emergency Medicine, Phramongkutklao College of Medicine Bangkok 10440, Thailand http://dx.doi.org/10.1016/j.ajem.2014.11.018 References [1] Bouabdallaoui N, Arlet JB, Hagege AA. Cardiogenic shock, asthma, and hypereosinophilia. Am J Emerg Med 2014 [Epub ahead of print]. [2] Ungprasert P, Srivali N, Cheungpasitporn W, Schaeffer CS. Is it acute coronary syndrome or Churg-Strauss syndrome? Am J Emerg Med 2013;31(1):270.e5–8. [3] Guillevin L, Cohen P, Mahr A, Arene J, Mouthon L, Puechal X, et al. Treatment of polyarteritis nodosa and microscopic polyangiitis with poor prognosis factors: a prospective trial comparing glucocorticoids and six or twelve cyclophosphamide pulses in sixty-five patients. Arthritis Rheum 2003;49(1):93–100.
Adherence to a clinical decision policy for head computed tomography in adult mild traumatic brain injury ☆,☆☆,★ To the Editor, Increases in emergency department (ED) computed tomography (CT) use have raised concern over potential overutilization [1,2]. Evidencebased guidelines, such as the American College of Emergency Physicians (ACEP) clinical policy on neuroimaging for adult traumatic brain injury (TBI) [3] are designed to reduce unnecessary imaging. Our primary objective was to assess adherence to the ACEP policy (meeting either level A or B recommendations). Our secondary objective was to compare lengths of stay for those who received and did not receive a head CT that was not recommended by the policy. We hypothesized weak adherence to the ACEP policy with significant CT use, when it was not recommended. We conducted a retrospective analysis of ED visits for acute mild TBI from January 1, 2010, to December 31, 2011 to 3 urban EDs within a university health system. Annual combined census was approximately 140 000 visits during the study period, with 77 attending emergency physicians providing 24-hour coverage. Our university's institutional review board approved the study. To not undersample specific attending physicians, we sampled a minimum of 10 visits from each attending. We included patients 18 years or older with a chief complaint indicative of trauma (eg, motor vehicle collision, head laceration, and fall) and an International Classification of Diseases, Ninth Edition, Clinical Modification diagnosis code for head injury (800-803, 850-854, 873, 910, and 959). “Trauma activations” were not included, as these patients are not managed by emergency physicians at our institution. Per the ACEP policy, we excluded patients with injuries that occurred more than 24 hours prior, and those without mild TBI (eg, Glasgow Coma Scale [GCS] b 14 and penetrating head injuries.) A trained abstractor reviewed electronic records, and a second abstractor reviewed a 10% sample to assess reliability. There was 95% crude agreement between reviewers; κ was 0.72 (95% confidence interval, 0.52, 0.85), indicating substantial agreement [4]. We used descriptive statistics to describe the study population and compared medians using the Wilcoxon rank sum test. We used SAS statistical software, version 9.3 (SAS Institute, Inc, Cary, NC), for analyses. There were 4538 TBI visits not designated as “trauma activations,” and 834 visits (18%) were reviewed. Seventy-six patients were excluded (12 with a GCS b 14 and 64 with injuries N 24-hour-old) resulting in a final study population of 758 patients with mild TBI. Fifty-three percent were male, 58% were Black, and most (84%) were discharged (Table). Head ☆ JRM was supported by Award Number 5K12HL109068 from the National Heart, Lung, and Blood Institute. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Heart, Lung, and Blood Institute or the National Institutes of Health. ☆☆ The authors have no relevant financial conflicts of interest to disclose. ★ Presented as an oral abstract at the Society for Academic Emergency Medicine Annual Meeting, Dallas, TX, 2014.
299
Table Characteristics of visits for mild TBI (n = 758) Characteristic
n (%)
Sex, male
400 (52.8)
Age (y), median (range)
43 (18-101)
Race/ethnicity Black, non-Hispanic White, non-Hispanic Other Missing Primary insurance Private Medicare Medicaid Self-pay Missing Triage level (ESI)a 1 2 3 4 5 Discharged Clinical signs/symptomsb Loss of consciousness Amnesia Headache Emesis Age N60 years Drug or alcohol intoxication Short-term memory deficits Trauma above the clavicle Posttraumatic seizure GCS, b15 Focal neurologic deficit Coagulopathy Severe headachec Age ≥65 years Signs of basilar skull fracture Dangerous mechanism of injuryd
425 (56.1) 245 (32.3) 65 (8.6) 23 (3.0) 211 (30.9) 178 (26.1) 145 (21.3) 148 (21.7) 76 (10.0) 1 (0.13) 117 (15.4) 462 (60.1) 172 (22.7) 6 (0.79) 634 (83.6) 177 (23.4) 72 (9.5) 418 (55.2) 18 (2.4) 206 (27.2) 109 (14.4) 17 (2.2) 536 (70.7) 4 (0.5) 30 (4) 17 (2.2) 52 (6.9) 8 (1) 179 (23.6) 0 (0) 42 (5.5)
a
Emergency severity index. Percentages total more than 100% as signs/symptoms were not mutually exclusive. c Defined as identification of headache in the chart with a preceding modifier indicating the headache was severe (eg, “bad” and “worst”). d Ejection from motor vehicle, pedestrian struck, and fall from more than 3 feet or 5 stairs. b
CT was recommended per the ACEP policy for 53% of patients, and CT was performed for 71.2% of patients. Overall, there was 75% adherence to the policy (Figure). Specifically, a CT was performed in 94% of cases, when it was recommended. However, a CT was performed in 46% of the 360 cases in which it was not recommended. Among those for whom a CT was not recommended, median length of stay was 4.8 hours (Interquartile range, 3.3-5.7), when a CT was performed compared with 2.2 hours (Interquartile range, 1.1-2.9), when a CT was not performed. In this study, we found high overall adherence to the ACEP policy. However, we also found that most of nonadherence was due to CT use, when it was not recommended by the policy. Computed tomography overutilization is a topic of concern given studies of increasing imaging trends without commensurate increases in identified injuries and pathology [1,2,5]. Some reasons for these trends may include patient/ family preference for imaging, physician discomfort with diagnostic uncertainty, and malpractice fear associated with a missed diagnosis [6]. In addition, clinicians may perceive that imaging will expedite ED diagnosis and patient disposition [6]; however, our data, similar to that of Kocher et al [7] suggest the opposite is true. A recent, prospective study demonstrated similar adherence (78%) to the ACEP policy but did not demonstrate a significant proportion of CT use, when CT was not recommended [7]. This is likely because of the high percentage of patients (83%) for which a CT would have been recommended per the ACEP policy. This difference in recommended
300
Correspondence / American Journal of Emergency Medicine 33 (2015) 290–304 [4] Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977;1:159–74. [5] Korley FK, Pham JC, Kirsch TD. Use of advanced radiology during visits to US emergency departments for injury-related conditions, 1998-2007. JAMA 2010; 304:1465–71. [6] Rohacek M, Albrecht M, Kleim B, Zimmermann H, Exadaktylos A. Reasons for ordering computed tomography scans of the head in patients with minor brain injury. Injury 2012;43:1415–8. [7] Kocher KE, Meurer WJ, Desmond JS, Nallamothu BK. Effect of testing and treatment on emergency department length of stay using a national database. Acad Emerg Med 2012;19:525–34.
What diseases are disguised as dengue? Figure. Frequency of head CT recommended by the ACEP clinical policy and head CT performed for mild traumatic brain injury.
CT use may be due to the different study populations. Specifically, “trauma activations” were not included in our study; therefore, our population may reflect those less severely injured. Our study has limitations. First, we relied on data recorded in the medical record; therefore, there was potential for misclassification of policy adherence. Specifically, it is possible that a patient who received a CT met the policy recommendations for CT; however, the chart was lacking documentation. There may have been undocumented factors related to the decision to obtain a CT, such as patient preference. However, our study sought to determine policy adherence and not necessarily whether imaging was justified. Finally, this study was within a single health system, and, therefore, the data may not generalize across all settings. In summary, emergency physicians adhere to the ACEP clinical policy for neuroimaging in mild TBI in cases where CT is recommended; however, improvements are needed to promote the safe avoidance of CT in cases, when it is not recommended.
Jennifer R. Marin, MD, MSc Departments of Pediatrics and Emergency Medicine University of Pittsburgh School of Medicine, Pittsburgh, PA Corresponding author. Departments of Pediatrics and Emergency Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA Tel.: +412 692 7692 (office); fax: +412 692 7464 E-mail address: [email protected] Frances S. Shofer, PhD Department of Emergency Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA Ivy Chang, BA Warren Alpert Medical School of Brown University, Providence, RI Angela M. Mills, MD Department of Emergency Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA
http://dx.doi.org/10.1016/j.ajem.2014.11.017 References [1] Larson DB, Johnson LW, Schnell BM, Salisbury SR, Forman HP. National trends in CT use in the emergency department: 1995-2007. Radiology 2011;258:164–73. [2] Kocher KE, Meurer WJ, Fazel R, Krumholz HM, Nallamothu BK. National trends in use of computed tomography in the emergency department. Ann Emerg Med 2011;58: 452–3. [3] Jagoda AS, Bazarian JJ, Bruns Jr JJ, Cantrill SV, Gean AD, Howard PK, et al. Clinical policy: neuroimaging and decision making in adult mild traumatic brain injury in the acute setting. Ann Emerg Med 2008;52:714–48.
To the Editor, Dengue is the most common arthropod-borne viral disease and is prevalent in tropical and subtropical areas. The typical manifestations of dengue include fever, headache and myalgia, and these symptoms are commonly present in various inflammatory and infectious diseases. Therefore, the accurate diagnosis of dengue relies on laboratory studies [1]. Currently, capture enzyme-linked immunosorbent assay for dengue immunoglobulin M antibody (dengue IgM) is the most widely applied test. However, dengue IgM antibodies cross-react with other flaviviruses, and a number of non-dengue diseases have been reported to produce positive reactions in dengue serological tests [1–5]. When such non-dengue diseases are mistaken for dengue, appropriate management of the actual disease is delayed. Therefore, we conducted the retrospective study to identify the diseases that can present false positive dengue IgM results. We reviewed all emergency department patients who underwent single dengue IgM from April 1, 2010 to May 31, 2011 in the Chi-Mei Medical Center. Among the 292 reviewed patients, 68 cases exhibited positive results for dengue IgM. The patients with positive dengue IgM test results underwent further examinations, and the diagnoses of dengue followed the definitions of the World Health Organization [6]. The results of further tests yielded 34 dengue patients (dengue group) and 34 uncertain cases. Of the uncertain cases, we were able to identify the actual disease in 10 patients (non-dengue group). We then applied Student’s t-tests to evaluate the differences in continuous variables between the dengue and non-dengue patients. The dengue group included 33 adults and 1 child, and the non-dengue group included 7 adults and 3 children. The adult age distributions were similar between the dengue and non-dengue patients (dengue vs. non-dengue, 62 vs. 60 years old, respectively, p = 0.334). Infectious diseases were present in the majority of the non-dengue group and including urinary tract infection, cholecystitis, perforated peptic ulcer and pediatric tonsillitis. The other non-dengue patients had systemic lupus erythematosus and Kawasaki disease. All of the non-dengue patients and 20 of the dengue patients were admitted. The non-dengue group exhibited longer hospital stays (dengue vs. non-dengue, 6.3 vs. 11.7 days, respectively, p = 0.010). Three non-dengue patients required intensive care, and surgical interventions were performed in three non-dengue patients (Table). All of the non-dengue patients and only 2 of the 34 dengue patients had C-reactive protein (CRP) levels above 15 mg/L (dengue vs. nondengue, 7 vs. 81, respectively, p = 0.000). Compared with the nondengue patients, the dengue patients exhibited lower white cell counts (dengue vs. non-dengue, 4021 vs. 9430/mm3, respectively, p = 0.000) and higher hematocrit levels (dengue vs. non-dengue, 42.1 vs. 37.2 %, respectively, p = 0.005). There was no significant difference in platelet counts between the two groups (dengue vs. non-dengue, 103300 vs. 102700/mm3, respectively, p = 0.920). Southern Taiwan is a dengue epidemic area, and emergency physicians are familiar with the manifestations of dengue. Accordingly, febrile patients presenting with thrombocytopenia and myalgia typically undergo dengue IgM testing to screen for dengue.
Vareena Laohaphan, MD Department of Emergency Medicine, Phramongkutklao College of Medicine Bangkok 10440, Thailand http://dx.doi.org/10.1016/j.ajem.2014.11.018 References [1] Bouabdallaoui N, Arlet JB, Hagege AA. Cardiogenic shock, asthma, and hypereosinophilia. Am J Emerg Med 2014 [Epub ahead of print]. [2] Ungprasert P, Srivali N, Cheungpasitporn W, Schaeffer CS. Is it acute coronary syndrome or Churg-Strauss syndrome? Am J Emerg Med 2013;31(1):270.e5–8. [3] Guillevin L, Cohen P, Mahr A, Arene J, Mouthon L, Puechal X, et al. Treatment of polyarteritis nodosa and microscopic polyangiitis with poor prognosis factors: a prospective trial comparing glucocorticoids and six or twelve cyclophosphamide pulses in sixty-five patients. Arthritis Rheum 2003;49(1):93–100.
Adherence to a clinical decision policy for head computed tomography in adult mild traumatic brain injury ☆,☆☆,★ To the Editor, Increases in emergency department (ED) computed tomography (CT) use have raised concern over potential overutilization [1,2]. Evidencebased guidelines, such as the American College of Emergency Physicians (ACEP) clinical policy on neuroimaging for adult traumatic brain injury (TBI) [3] are designed to reduce unnecessary imaging. Our primary objective was to assess adherence to the ACEP policy (meeting either level A or B recommendations). Our secondary objective was to compare lengths of stay for those who received and did not receive a head CT that was not recommended by the policy. We hypothesized weak adherence to the ACEP policy with significant CT use, when it was not recommended. We conducted a retrospective analysis of ED visits for acute mild TBI from January 1, 2010, to December 31, 2011 to 3 urban EDs within a university health system. Annual combined census was approximately 140 000 visits during the study period, with 77 attending emergency physicians providing 24-hour coverage. Our university's institutional review board approved the study. To not undersample specific attending physicians, we sampled a minimum of 10 visits from each attending. We included patients 18 years or older with a chief complaint indicative of trauma (eg, motor vehicle collision, head laceration, and fall) and an International Classification of Diseases, Ninth Edition, Clinical Modification diagnosis code for head injury (800-803, 850-854, 873, 910, and 959). “Trauma activations” were not included, as these patients are not managed by emergency physicians at our institution. Per the ACEP policy, we excluded patients with injuries that occurred more than 24 hours prior, and those without mild TBI (eg, Glasgow Coma Scale [GCS] b 14 and penetrating head injuries.) A trained abstractor reviewed electronic records, and a second abstractor reviewed a 10% sample to assess reliability. There was 95% crude agreement between reviewers; κ was 0.72 (95% confidence interval, 0.52, 0.85), indicating substantial agreement [4]. We used descriptive statistics to describe the study population and compared medians using the Wilcoxon rank sum test. We used SAS statistical software, version 9.3 (SAS Institute, Inc, Cary, NC), for analyses. There were 4538 TBI visits not designated as “trauma activations,” and 834 visits (18%) were reviewed. Seventy-six patients were excluded (12 with a GCS b 14 and 64 with injuries N 24-hour-old) resulting in a final study population of 758 patients with mild TBI. Fifty-three percent were male, 58% were Black, and most (84%) were discharged (Table). Head ☆ JRM was supported by Award Number 5K12HL109068 from the National Heart, Lung, and Blood Institute. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Heart, Lung, and Blood Institute or the National Institutes of Health. ☆☆ The authors have no relevant financial conflicts of interest to disclose. ★ Presented as an oral abstract at the Society for Academic Emergency Medicine Annual Meeting, Dallas, TX, 2014.
299
Table Characteristics of visits for mild TBI (n = 758) Characteristic
n (%)
Sex, male
400 (52.8)
Age (y), median (range)
43 (18-101)
Race/ethnicity Black, non-Hispanic White, non-Hispanic Other Missing Primary insurance Private Medicare Medicaid Self-pay Missing Triage level (ESI)a 1 2 3 4 5 Discharged Clinical signs/symptomsb Loss of consciousness Amnesia Headache Emesis Age N60 years Drug or alcohol intoxication Short-term memory deficits Trauma above the clavicle Posttraumatic seizure GCS, b15 Focal neurologic deficit Coagulopathy Severe headachec Age ≥65 years Signs of basilar skull fracture Dangerous mechanism of injuryd
425 (56.1) 245 (32.3) 65 (8.6) 23 (3.0) 211 (30.9) 178 (26.1) 145 (21.3) 148 (21.7) 76 (10.0) 1 (0.13) 117 (15.4) 462 (60.1) 172 (22.7) 6 (0.79) 634 (83.6) 177 (23.4) 72 (9.5) 418 (55.2) 18 (2.4) 206 (27.2) 109 (14.4) 17 (2.2) 536 (70.7) 4 (0.5) 30 (4) 17 (2.2) 52 (6.9) 8 (1) 179 (23.6) 0 (0) 42 (5.5)
a
Emergency severity index. Percentages total more than 100% as signs/symptoms were not mutually exclusive. c Defined as identification of headache in the chart with a preceding modifier indicating the headache was severe (eg, “bad” and “worst”). d Ejection from motor vehicle, pedestrian struck, and fall from more than 3 feet or 5 stairs. b
CT was recommended per the ACEP policy for 53% of patients, and CT was performed for 71.2% of patients. Overall, there was 75% adherence to the policy (Figure). Specifically, a CT was performed in 94% of cases, when it was recommended. However, a CT was performed in 46% of the 360 cases in which it was not recommended. Among those for whom a CT was not recommended, median length of stay was 4.8 hours (Interquartile range, 3.3-5.7), when a CT was performed compared with 2.2 hours (Interquartile range, 1.1-2.9), when a CT was not performed. In this study, we found high overall adherence to the ACEP policy. However, we also found that most of nonadherence was due to CT use, when it was not recommended by the policy. Computed tomography overutilization is a topic of concern given studies of increasing imaging trends without commensurate increases in identified injuries and pathology [1,2,5]. Some reasons for these trends may include patient/ family preference for imaging, physician discomfort with diagnostic uncertainty, and malpractice fear associated with a missed diagnosis [6]. In addition, clinicians may perceive that imaging will expedite ED diagnosis and patient disposition [6]; however, our data, similar to that of Kocher et al [7] suggest the opposite is true. A recent, prospective study demonstrated similar adherence (78%) to the ACEP policy but did not demonstrate a significant proportion of CT use, when CT was not recommended [7]. This is likely because of the high percentage of patients (83%) for which a CT would have been recommended per the ACEP policy. This difference in recommended
300
Correspondence / American Journal of Emergency Medicine 33 (2015) 290–304 [4] Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977;1:159–74. [5] Korley FK, Pham JC, Kirsch TD. Use of advanced radiology during visits to US emergency departments for injury-related conditions, 1998-2007. JAMA 2010; 304:1465–71. [6] Rohacek M, Albrecht M, Kleim B, Zimmermann H, Exadaktylos A. Reasons for ordering computed tomography scans of the head in patients with minor brain injury. Injury 2012;43:1415–8. [7] Kocher KE, Meurer WJ, Desmond JS, Nallamothu BK. Effect of testing and treatment on emergency department length of stay using a national database. Acad Emerg Med 2012;19:525–34.
What diseases are disguised as dengue? Figure. Frequency of head CT recommended by the ACEP clinical policy and head CT performed for mild traumatic brain injury.
CT use may be due to the different study populations. Specifically, “trauma activations” were not included in our study; therefore, our population may reflect those less severely injured. Our study has limitations. First, we relied on data recorded in the medical record; therefore, there was potential for misclassification of policy adherence. Specifically, it is possible that a patient who received a CT met the policy recommendations for CT; however, the chart was lacking documentation. There may have been undocumented factors related to the decision to obtain a CT, such as patient preference. However, our study sought to determine policy adherence and not necessarily whether imaging was justified. Finally, this study was within a single health system, and, therefore, the data may not generalize across all settings. In summary, emergency physicians adhere to the ACEP clinical policy for neuroimaging in mild TBI in cases where CT is recommended; however, improvements are needed to promote the safe avoidance of CT in cases, when it is not recommended.
Jennifer R. Marin, MD, MSc Departments of Pediatrics and Emergency Medicine University of Pittsburgh School of Medicine, Pittsburgh, PA Corresponding author. Departments of Pediatrics and Emergency Medicine, University of Pittsburgh School of Medicine, Pittsburgh, PA Tel.: +412 692 7692 (office); fax: +412 692 7464 E-mail address: [email protected] Frances S. Shofer, PhD Department of Emergency Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA Ivy Chang, BA Warren Alpert Medical School of Brown University, Providence, RI Angela M. Mills, MD Department of Emergency Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA
http://dx.doi.org/10.1016/j.ajem.2014.11.017 References [1] Larson DB, Johnson LW, Schnell BM, Salisbury SR, Forman HP. National trends in CT use in the emergency department: 1995-2007. Radiology 2011;258:164–73. [2] Kocher KE, Meurer WJ, Fazel R, Krumholz HM, Nallamothu BK. National trends in use of computed tomography in the emergency department. Ann Emerg Med 2011;58: 452–3. [3] Jagoda AS, Bazarian JJ, Bruns Jr JJ, Cantrill SV, Gean AD, Howard PK, et al. Clinical policy: neuroimaging and decision making in adult mild traumatic brain injury in the acute setting. Ann Emerg Med 2008;52:714–48.
To the Editor, Dengue is the most common arthropod-borne viral disease and is prevalent in tropical and subtropical areas. The typical manifestations of dengue include fever, headache and myalgia, and these symptoms are commonly present in various inflammatory and infectious diseases. Therefore, the accurate diagnosis of dengue relies on laboratory studies [1]. Currently, capture enzyme-linked immunosorbent assay for dengue immunoglobulin M antibody (dengue IgM) is the most widely applied test. However, dengue IgM antibodies cross-react with other flaviviruses, and a number of non-dengue diseases have been reported to produce positive reactions in dengue serological tests [1–5]. When such non-dengue diseases are mistaken for dengue, appropriate management of the actual disease is delayed. Therefore, we conducted the retrospective study to identify the diseases that can present false positive dengue IgM results. We reviewed all emergency department patients who underwent single dengue IgM from April 1, 2010 to May 31, 2011 in the Chi-Mei Medical Center. Among the 292 reviewed patients, 68 cases exhibited positive results for dengue IgM. The patients with positive dengue IgM test results underwent further examinations, and the diagnoses of dengue followed the definitions of the World Health Organization [6]. The results of further tests yielded 34 dengue patients (dengue group) and 34 uncertain cases. Of the uncertain cases, we were able to identify the actual disease in 10 patients (non-dengue group). We then applied Student’s t-tests to evaluate the differences in continuous variables between the dengue and non-dengue patients. The dengue group included 33 adults and 1 child, and the non-dengue group included 7 adults and 3 children. The adult age distributions were similar between the dengue and non-dengue patients (dengue vs. non-dengue, 62 vs. 60 years old, respectively, p = 0.334). Infectious diseases were present in the majority of the non-dengue group and including urinary tract infection, cholecystitis, perforated peptic ulcer and pediatric tonsillitis. The other non-dengue patients had systemic lupus erythematosus and Kawasaki disease. All of the non-dengue patients and 20 of the dengue patients were admitted. The non-dengue group exhibited longer hospital stays (dengue vs. non-dengue, 6.3 vs. 11.7 days, respectively, p = 0.010). Three non-dengue patients required intensive care, and surgical interventions were performed in three non-dengue patients (Table). All of the non-dengue patients and only 2 of the 34 dengue patients had C-reactive protein (CRP) levels above 15 mg/L (dengue vs. nondengue, 7 vs. 81, respectively, p = 0.000). Compared with the nondengue patients, the dengue patients exhibited lower white cell counts (dengue vs. non-dengue, 4021 vs. 9430/mm3, respectively, p = 0.000) and higher hematocrit levels (dengue vs. non-dengue, 42.1 vs. 37.2 %, respectively, p = 0.005). There was no significant difference in platelet counts between the two groups (dengue vs. non-dengue, 103300 vs. 102700/mm3, respectively, p = 0.920). Southern Taiwan is a dengue epidemic area, and emergency physicians are familiar with the manifestations of dengue. Accordingly, febrile patients presenting with thrombocytopenia and myalgia typically undergo dengue IgM testing to screen for dengue.
