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991.
Ultrasound (US) and laboratory testing are initial diagnostic tests for acute appendicitis. A diagnostic dilemma develops when the appendix is not visualized on US. Objective: To determine if specific US findings and/or laboratory results predict acute appendicitis when the appendix is not visualized. Methods: A prospective study was conducted on children (birth-18?yrs) presenting to the pediatric emergency department with suspected acute appendicitis who underwent right lower quadrant US.Children with previous appendectomy, US at another facility, or eloped were excluded. US findings analyzed: inflammatory changes, right lower quadrant and lower abdominal fluid, tenderness during US exam and lymph nodes. Diagnoses were confirmed via surgical pathology. Results 1252 subjects were enrolled, 60.8% (762) had appendix visualized and 39.1% (490) did not. In children where the appendix was not seen, 6.7% [33] were diagnosed with appendicitis. Among patients with a non-visualized appendix, the likelihood of appendicitis was significantly greater if: inflammatory changes in the RLQ (OR 18.0, 95% CI 4.5–72.1), CRP >0.5?mg/dL (OR 2.64, 95% CI 1.0–6.8), or WBC?>?10 (OR 4.36, 95% CI 1.66–11.58). Duration of abdominal pain >3?days was significantly less likely associated with appendicitis in this model (OR 0.34, 95% CI 0.003–0.395). Combined, the absence inflammatory changes, CRP?<?0.5?mg/dL, WBC?<?10, and pain, ≤3?days had a NPV of 94.0%. Conclusion When the appendix is not visualized on US, predictors for appendicitis include the presence of inflammatory changes in the RLQ, an elevated WBC/CRP and abdominal pain <3?days.  相似文献   
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Phang  P. Terry 《Abdominal imaging》2019,44(11):3740-3742
Abdominal Radiology -  相似文献   
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We generated a novel scoring system to improve the test characteristics of D-dimer in patients with suspected PE (pulmonary emboli).Electronic Medical Record data were retrospectively reviewed on Emergency Department (ED) patients 18?years or older for whom a D-dimer and imaging were ordered between June 4, 2012 and March 30, 2016. Symptoms (dyspnea, unilateral leg swelling, hemoptysis), age, vital signs, medical history (cancer, recent surgery, medications, history of deep vein thrombosis or PE, COPD, smoking), laboratory values (quantitative D-dimer, platelets, and mean platelet volume (MPV)), and imaging results (CT, VQ) were collected.Points were designated to factors that were significant in two multiple regression analyses, for PE or positive D-dimer. Points predictive of PE were designated positive values and points predictive of positive D-dimer, irrespective of presence of PE, were designated negative values.The DAGMAR (D-dimer Assay-Guided Moderation of Adjusted Risk) score was developed using age and platelet adjustment and points for factors associated with PE and elevated D-dimer.Of 8486 visits reviewed, 3523 were unique visits with imaging, yielding 2253 (26.5%) positive D-dimers. 3501 CT scans and 156 VQ scans were completed, detecting 198 PE.In our cohort, a DAGMAR Score?<?2 equated to overall PE risk?<?1.2%. Specificity improved (38% to 59%) without compromising sensitivity (94% to 96%). Use of the DAGMAR Score would have reduced CT scans from 2253 to 1556 and lead to fewer false negative results.By considering factors that affect D-dimer and also PE, we improved specificity without compromising sensitivity.  相似文献   
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Background

Blastomycosis is caused by a fungus endemic to states and providences bordering the Lawrence Rivers and the Great Lakes. It can lead to significant pathology in both immunocompetent and immunocompromised hosts. This case report describes disseminated blastomycosis in an otherwise healthy 16-year-old patient.

Case Report

A 16-year-old male presented with a chief complaint of flank pain. In the Emergency Department he described additional symptoms of emesis, cough, and weight loss. His vitals were appropriate; however, he had absent lung sounds in the left lower lung field, splenomegaly, a left thigh abscess, and lower-extremity edema. Imaging studies showed a left pleural effusion, mediastinal shift to the right, splenomegaly, a left psoas abscess, and undifferentiated bony involvement of L1 transverse process and the left 12th rib. Abscess cultures grew Blastomyces dermatitides. He was treated with amphotericin B, demonstrated clinical improvement, and was discharged on itraconazole.

Why Should an Emergency Physician Be Aware of This?

The case fatality rate of blastomycosis is estimated at between 4.3% and 6.4%. Patients with solid organ transplant and associated immune suppression had a mortality of 33–38%. Given the nonspecific nature of this condition, a high level of suspicion is required for diagnosis, and early diagnosis is essential, as end organ damage in disseminated disease can include high-severity illness, including acute respiratory distress syndrome and central nervous system dysfunction. If any patient presents with symptomatology involving both skin and pulmonary systems, blastomycosis must be entertained as a possible diagnosis. Prompt diagnosis and treatment will significantly improve morbidity and mortality.  相似文献   
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