Kessler Nicolas, Cyteval Catherine, Gallix Benoît, Lesnik Alvian, Blayac Paul-Marie, Pujol Joseph, Bruel Jean-Michel, Taourel Patrice
Department of Radiology, Lapeyronie Hospital, 371 Avenue du Doyen Gaston Giraud, 34295 Montpellier 5, France.
Radiology. 2004 Feb;230(2):472-8. doi: 10.1148/radiol.2302021520. Epub 2003 Dec 19.
To evaluate the sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of ultrasonography (US), Doppler US, and laboratory findings in the diagnosis of appendicitis.
A total of 125 consecutive patients suspected of having appendicitis were prospectively included for US appendiceal (diameter enlarged to 6 mm or greater, intraluminal fluid, lack of compressibility) and periappendiceal (periileal inflammatory changes, cecal wall thickening, periileal lymph nodes, peritoneal fluid) evaluation, Doppler US evaluation (appendiceal wall signal), and laboratory assessment (leukocytosis, C-reactive protein [CRP]). Definite diagnoses were established at surgery in 61 patients, at endoscopy with biopsy in two patients, and at clinical follow-up in 62 patients.
The prevalence of appendicitis was 46%. The appendix was identified with US in 86% of the patients, which included 96% of patients with and 72% of patients without appendicitis. The most accurate appendiceal finding for appendicitis was a diameter of 6 mm or larger, with a sensitivity, specificity, NPV, and PPV of 98%. The lack of visualization of the appendix with US had an NPV of 90%. The most accurate periappendiceal finding of appendicitis was the presence of inflammatory fat changes, with an NPV of 91% and a PPV of 76%, whereas other findings had both NPV and PPV less than 65%. An increase in both white blood cell (WBC) count and CRP level had a PPV of 71%, whereas combined normal WBC count and CRP value had an NPV of 84%.
A threshold 6-mm diameter of the appendix under compression is the most accurate US finding for appendicitis and has high NPV and PPV.
评估超声（US）、多普勒超声及实验室检查结果在阑尾炎诊断中的敏感性、特异性、阴性预测值（NPV）和阳性预测值（PPV）。
前瞻性纳入125例连续怀疑患有阑尾炎的患者，进行阑尾超声检查（直径增大至6mm或更大、腔内积液、不可压缩）及阑尾周围超声检查（回肠周围炎症改变、盲肠壁增厚、回肠周围淋巴结、腹腔积液）、多普勒超声检查（阑尾壁信号）以及实验室评估（白细胞增多、C反应蛋白[CRP]）。61例患者通过手术确诊，2例患者通过内镜活检确诊，62例患者通过临床随访确诊。
阑尾炎的患病率为46%。86%的患者通过超声发现阑尾，其中包括96%患有阑尾炎和72%未患阑尾炎的患者。阑尾炎最准确的阑尾表现是直径6mm或更大，其敏感性、特异性、NPV和PPV为98%。超声未显示阑尾的NPV为90%。阑尾炎最准确的阑尾周围表现是存在炎性脂肪改变，NPV为91%，PPV为76%，而其他表现的NPV和PPV均低于65%。白细胞（WBC）计数和CRP水平均升高的PPV为71%，而WBC计数和CRP值均正常的NPV为84%。
受压阑尾直径阈值为6mm是阑尾炎最准确的超声表现，具有较高的NPV和PPV。
