Table 1.
Variables with significant differences between study groups as identified in nonparametric, univariable analysis. Odds ratio and 95% confidence interval calculated using univariable logistic regression. For rectal exam results, a univariable analysis of association for each type of rectal finding is included
| Variable | Idiopathic, n (%) | NSII, n (%) | P-value | OR | CI (95%) | ||
|---|---|---|---|---|---|---|---|
| Season at presentationa | 0.001 | ||||||
| Spring/Summer | 41 (38) | 2 (10) | Reference variable | ||||
| Autumn | 36 (34) | 3 (15) | 1.7 | 0.3–13.5 | |||
| Winter | 30 (28) | 15 (75) | 10.2 | 2.6–68.2 | |||
| Colic at admissiona | 0.02 | ||||||
| No colic at admission | 30 (28) | 4 (20) | Reference variable | ||||
| Colic grade at admission | |||||||
| Grade 1 | 67 (63) | 12 (60) | 1.50 | 0.48–5.67 | |||
| Grade 2 | 8 (7) | 0 (0) | N/A | N/A | |||
| Grade 3 | 2 (2) | 4 (20) | 17.50 | 2.62–161.78 | |||
| Fever at admission (≥ 38.5 ℃)a | 0.03 | ||||||
| No fever at admission | 53 (50) | 4 (20) | Reference variable | ||||
| Fever at admission | 52 (49) | 16 (80) | 0.3 | 0.1–0.8 | |||
| Missing | 2 | 0 | |||||
| Rectal examinationa | < 0.001 | ||||||
| Normal rectal exam | 54 (51) | 1 (5) | Reference variable | ||||
| One or several rectal findings | 53 (49) | 19 (95) | 19.4 | 3.8–354.0 | |||
| Mass/adhesions | 0 (0) | 13 (65) | Part of case definition | ||||
| Impaction | 44 (41) | 9 (45) | 1.2 | 0.4–3.1 | |||
| Gas distention | 7 (7) | 4 (20) | 3.6 | 0.9–13.3 | |||
| Other abnormal finding | 4 (4) | 1 (5) | 1.4 | 0.0–9.8 | |||
| WBC (median [IQR])b | 7.10 [5.54, 9.30] × 109/L | 3.50 [3.05, 5.01] × 109/L | < 0.001 | 0.04† | 0.28–0.64 | ||
| Missing | 6 | 5 | |||||
| Neutrophils (median [IQR])b | 5.00 [3.60, 7.10] × 109/L | 2.40 [1.40, 3.19] × 109/L | < 0.001 | 0.55† | 0.38–0.75 | ||
| Missing | 7 | 4 | |||||
| Elevated fibrinogen levela | 13 (16) | 8 (53) | 0.01 | 4.70 | 1.28–17.19 | ||
| Missing | 23 | 5 | |||||
| Peritoneal total protein level (median [IQR])b | 40.00 [34.00, 50.00] g/L | 50.00 [40.00, 60.00] g/L | 0.01 | 1.38‡ | 1.10–1.78 | ||
| Missing | 16 | 3 | |||||
a Fisher exact test, b Kruskal-Wallis rank sum test, † for every increase of 1.0 × 109/L, ‡ for every increase in 5.0 g/L