Clinical differentiation of acute appendicitis and right colonic diverticulitis: A case-control study

Table 1 Patient characteristics n (%)

Characteristics	Appendicitis (n = 236)	Diverticulitis (n = 133)	P-value
Age > 40 (yr)	96.0 (40.7)	70.0 (52.6)	0.027a
Age (years)	35.5 [25-50.5]	41.0 [31.0-51.0]	0.011a
Male sex	129 (54.7)	83 (62.4)	0.149
Onset-to-visit interval (d)	1 [0-1]	2 [1-3]	< 0.001a
Epigastric/periumbilical pain	119 (50.4)	47 (35.3)	0.005a
RLQ pain	171 (72.5)	125 (94.0)	< 0.001a
Nausea/vomiting	123 (52.1)	19 (14.3)	< 0.001a
Diarrhea	46 (19.5)	25 (18.8)	0.871
Anorexia	64 (27.1)	21 (15.8)	0.013a
History of unresected appendicitis	32 (13.6)	3 (2.3)	< 0.001a
History of diverticulitis	2 (0.9)	22 (16.5)	< 0.001a
Diabetes mellitus	11 (4.7)	2 (1.5)	0.114
Hypertension	24 (10.2)	14 (10.5)	0.914
Dyslipidemia	21 (8.9)	15 (11.3)	0.459
Liver cirrhosis	0	1 (0.8)	0.182
Hemodialysis	0	1 (0.8)	0.182
Chronic lung diseases	2 (0.9)	1 (0.8)	0.922
Malignancy	1 (0.4)	2 (1.5)	0.267
Immunosuppressant use	1 (0.4)	3 (2.3)	0.103
Antiplatelet use	0	0	N/A
Fever	34 (14.4)	20 (15.0)	0.869
Shock	6 (2.5)	3 (2.3)	0.864
RLQ tenderness	230 (97.5)	127 (94.5)	0.306
Peritoneal signs	137 (58.1)	72 (54.1)	0.466
Leukocytosis	159 (67.4)	72 (54.1)	0.012a
Leukocyte count (103/mm3)	12.6 [10.1-15.2]	11.5 [9.3-13.5]	0.002a
High CRP level (> 3.0 mg/dL)	74 (31.4)	98 (73.7)	< 0.001a
CRP level (mg/dL)	1.1 [0.2-4.1]	4.9 [2.9-8.5]	< 0.001a
Creatinine level > 1.2 (mg/dL)	7 (3.0)	5 (3.8)	0.68
ALT level > 29 (IU/L)	38 (16.1)	24 (18.1)	0.632

^aP value < 0.05. AA: Acute appendicitis; ALT: Alanine aminotransferase; ARCD: Acute right colonic diverticulitis; CRP: C-reactive protein; N/A: Not applicable; RLQ: Right lower quadrant.

Table 2 Logistic regression for differentiating acute appendicitis from acute right colonic diverticulitis

	OR [95%CI]	P-value
Age >40 (yr)	0.62 [0.35-1.08]	0.093
Onset-to-visit interval (d)	0.84 [0.72-0.97]	0.021a
Epigastric/periumbilical pain	1.14 [0.65-2.00]	0.64
RLQ pain	0.28 [0.11-0.71]	0.007a
Nausea/vomiting	3.89 [2.04-7.42]	< 0.001a
Anorexia	2.13 [1.06-4.28]	0.033a
History of unresected appendicitis	3.09 [0.82-11.63]	0.095
History of diverticulitis	0.034 [0.0059-0.20]	< 0.001a
Leukocytosis	1.50 [0.86-2.60]	0.15
High CRP level (>3.0 mg/dL)	0.25 [0.14-0.43]	< 0.001a

^aP-value < 0.05. CRP: C-reactive protein; OR: Odds ratio; RLQ: Right lower quadrant.