Clinical significance of serum procalcitonin in patients with ulcerative colitis

Table 1 Baseline characteristics of patients with ulcerative colitis

	Mild-to-moderate1	Severe	P value
Age upon entry, yr (mean ± SD)	39.3 ± 12.5	40.0 ± 19.7	> 0.2
Gender, male/female	6/5	7/0	> 0.2
Extent of disease
Number of patients			> 0.2
Extensive	7	7
Left-side	4	0
Proctitis	0	0
Concomitant medication use
Number of patients			> 0.2
Sulfasalazine	3	0
5-ASA	9	7
Glucocorticoid	6	2
Immunomodulator	1	0

¹Severity assessments were based on Truelove and Witts’ severity index. Eighteen ulcerative colitis (UC) patients were included in the study. The distribution of age and sex was not significantly different between mild-to-moderate and severe UC. There was no difference in the extent of disease and concomitant medication use between mild-to-moderate and severe UC. ASA: 5-aminosalicylic acid.

Table 2 Sensitivity and specificity of procalcitonin and C-reactive protein for severe ulcerative colitis detection

Marker	Sensitivity	95%CI	Specificity	95%CI
Procalcitonin (ng/mL)
> 0.0250	100%	59.04-100.0	27.27%	6.022-60.97
> 0.0400	100%	59.04-100.0	72.73%	39.03-93.98
> 0.0550	100%	59.04-100.0	100%	71.51-100.0
> 0.0650	71.43%	29.04-96.33	100%	71.51-100.0
> 0.0850	57.14%	18.41-90.10	100%	71.51-100.0
> 0.1050	42.86%	9.899-81.59	100%	71.51-100.0
> 0.1150	28.57%	3.669-70.96	100%	71.51-100.0
> 0.1350	14.29%	0.3610-57.87	100%	71.51-100.0
C-reactive protein (mg/dL)
> 0.2500	100%	59.04-100.0	27.27%	6.022-60.97
> 0.5000	85.71%	42.13-99.64	36.36%	10.93-69.21
> 0.7000	85.71%	42.13-99.64	45.45%	16.75-76.62
> 0.9000	85.71%	42.13-99.64	63.64%	30.79-89.07
> 1.400	85.71%	42.13-99.64	72.73%	39.03-93.98
> 2.600	85.71%	42.13-99.64	81.82%	48.22-97.72
> 3.600	85.71%	42.13-99.64	90.91%	58.72-99.77
> 4.050	71.43%	29.04-96.33	90.91%	58.72-99.77
> 4.700	71.43%	29.04-96.33	100%	71.51-100.0
> 7.100	57.14%	18.41-90.10	100%	71.51-100.0
> 9.850	42.86%	9.899-81.59	100%	71.51-100.0
> 10.75	28.57%	3.669-70.96	100%	71.51-100.0
> 11.35	14.29%	0.3610-57.87	100%	71.51-100.0
> 11.35	14.29%	0.3610-57.87	100%	76.84-100.0

A procalcitonin cut-off value of 0.055 ng/mL had good diagnostic accuracy for detecting severe ulcerative colitis, as demonstrated by the sensitivity (100%; 95%CI: 59.04-100.0) and specificity (100%; 95%CI: 71.51-100.0) (Table 2). Moreover, at a cut-off level of C-reactive protein > 3.6 mg/dL, the sensitivity for detecting severe ulcerative colitis was 85.71% (95%CI: 42.13-99.64), and the specificity was 90.91% (95%CI: 58.72-99.77).