Association of serum procalcitonin and C-reactive protein levels with CURB-65 criteria among patients with community-acquired pneumonia

Figures & data

Figure 1 Association between serum levels of CRP (red line) and PCT (blue line) with CURB-65 criteria in the patients with CAP.

Abbreviations: CURB-65; CAP, community-acquired pneumonia; CRP, C-reactive protein; PCT, procalcitonin.

Table 1 Association between serum level of procalcitonin and CURB-65 criteria in the patients with CAP

CURB-65 criteria	Mean of procalcitonin (ng/mL)	Standard error	P-value
0	0.04	0.006
1	0.57	0.34
2	2.18	0.74	0.0001
3	6.97	4.95
4	12.89	7.34
5	8.12	–

Abbreviations: CURB-65; CAP, community-acquired pneumonia.

Table 2 Comparison of the mortality rate of the patients with CAP according to CURB-65 criteria ranking and serum levels of procalcitonin during length of hospital stay and 30-days follow-up

Variables	Death during hospital stay	Death during 30-days follow-up	Total death	P-value	P-value
	N (%)	N (%)	N (%)	Hospital stay	30-days follow-up
CURB-65 criterion
0	0 (0)	0 (0)	0 (0)
1	0 (0)	2 (9.52)	2 (9.52)
2	0 (0)	0 (0)	0 (0)	<0.001	<0.001
3	7 (35)	1 (5)	8 (40)
4	2 (28.57)	1 (14.28)	3 (42.85)
5	1 (100)	0 (0)	1 (100)
Serum levels of procalcitonin
<0.5	1 (2)	2 (4)	3 (6)	<0.001	0.01
≥0.5	9 (22.5)	2 (7.5)	11 (27.5)

Abbreviations: CURB-65; CAP, community-acquired pneumonia.

Table 3 Association between serum level of CRP and CURB-65 criteria in the patients with CAP

CURB-65 criteria	Mean of CRP (mg/L)	Standard error	P-value
0	34.66	11.47
1	51.94	9.24
2	69.34	7.87	0.007
3	114.31	12.23
4	91.5	24.46
5	108	–

Abbreviations: CURB-65; CAP, community-acquired pneumonia; CRP, C-reactive protein.

Figure 2 The receiver operating characteristic (ROC) curve illustrating the predictive ability of PCT against CURB-65 parameters.

Note: Area under ROC curve = 0.7150.
Abbreviations: CURB-65; PCT, procalcitonin.

Figure 3 The receiver operating characteristic (ROC) curve illustrating the predictive ability of CRP against CURB-65 parameters.

Note: Area under ROC curve = 0.6068.
Abbreviations: CURB-65, CRP, C-reactive protein.