Skip to main content

Table 4 Performance of each CT finding in differentiating complicated from uncomplicated appendicitis

From: Predictive ability of CT findings in the differentiation of complicated and uncomplicated appendicitis: a retrospective investigation of 201 patients undergone appendectomy at initial admission

CT findings Sensitivity Specificity Accuracy PLR NLR PPV NPV p value
Appendiceal diameter ≥ 12 mma 61.7 65.1 63.5 1.8 0.6 61.1 65.7 < 0.001
(51.1–71.5) (55.2–74.1) (56.4–70.2) (1.3–2.4) (0.4–0.8) (53.6–68.0) (58.9–72.0)
Tip appendiceal diameter ≥ 10 mmb (n = 186) 68.3 54.8 60.8 1.5 0.6 54.4 68.7 < 0.001
(57.1–78.1) (44.7–64.7) (53.3–67.8) (1.2–2.0) (0.4–0.8) (47.9–60.7) (60.4–75.9)
Mucosal hyperenhancement 10.9 57.6 35.5 0.3 1.6 18.7 41.9 0.396
(4.1–22.3) (47.6–67.1) (28.1–43.4) (0.1–0.6) (1.3–1.9) (9.5–33.6) (37.4–46.5)
Mucosal enhancement defect 83.2 79.3 81.1 4.0 0.2 78.2 84.0 < 0.001
(74.1–90.0) (70.3–86.5) (75.0–86.3) (2.7–5.9) (0.1–0.3) (71.0–84.0) (76.9–89.2)
Intraluminal appendicolith 52.6 77.4 65.7 2.3 0.6 67.5 64.6 < 0.001
(42.1–63.0) (68.2–84.9) (58.7–72.2) (1.6–3.5) (0.5–0.8) (58.3–75.7) (59.0–69.8)
Appendicolith causing obstruction 41.5 82.9 63.3 2.4 0.7 68.4 61.3 < 0.001
(31.4–52.1) (74.3–89.5) (56.2–70.0) (1.5–3.9) (0.6–0.9) (57.2–77.9) (56.6–65.7)
Fat stranding; moderate–severe 96.8 42.5 68.2 1.7 0.1 60.1 93.8 < 0.001
(91.1–99.3) (32.9–52.4) (61.2–74.5) (1.4–2.0) (0.0–0.2) (56.1–64.1) (82.8–97.9)
Phlegmon 10.5 99.1 57.2 11.2 0.9 90.9 55.3 0.003
(5.2–18.5) (94.9–100.0) (50.1–64.2) (1.5–85.6) (0.8–1.0) (56.6–98.7) (53.5–57.0)
Fluid collection 24.2 99.1 63.7 25.7 0.8 95.8 59.3 < 0.001
(16.0–34.1) (94.9–100.0) (56.6–70.3) (3.5–186.4) (0.7–0.9) (76.0–99.4) (56.5–62.1)
Extraluminal appendicolith 6.3 100.0 55.7 N/A 0.9 100.0 54.4 0.010
(2.4–13.2) (96.6–100.0) (48.6–62.7) (0.9–1.0)   (53.1–55.7)
Periappendiceal air 43.2 100.0 73.1 N/A 0.6 100.0 66.3 < 0.001
(33.0–53.7) (96.6–100.0) (66.5–79.1) (0.5–0.7)   (62.2–70.0)
Periappendiceal fluid 76.8 71.7 74.1 2.7 0.3 70.9 77.6 < 0.001
(67.1–84.9) (62.1–80.0) (67.5–80.0) (2.0–3.8) (0.2–0.5) (63.8–77.1) (70.2–83.6)
Ascites 46.3 84.9 66.7 3.1 0.6 73.3 63.8 < 0.001
(36.0–56.9) (76.7–91.1) (59.7–73.1) (1.9–5.1) (0.5–0.8) (62.5–81.9) (59.0–68.4)
Small bowel dilatation 15.8 98.1 59.2 8.4 0.9 88.2 56.5 < 0.001
(9.1–24.7) (93.4–99.8) (52.1–66.1) (2.0–35.7) (0.8–0.9) (63.8–97.0) (54.3–58.8)
Small bowel thickening 49.5 87.7 69.7 4.0 0.6 78.3 66.0 < 0.001
(39.1–59.9) (79.9–93.3) (62.8–75.9) (2.3–7.0) (0.5–0.7) (67.6–86.2) (61.1–70.5)
  1. aArea under ROC curve 0.687 (0.613–0.760)
  2. bArea under ROC curve 0.658 (0.580–0.736)
  3. PLR: Positive likelihood ratio, NLR: negative likelihood ratio, PPV: positive predictive value, NPV: negative predictive value, N/A: not available
  4. Those in brackets represent 95% confidence interval