Correlation analysis of dynamic changes of serum calprotectin level and prognosis in patients with severe pneumonia

doi:10.3877/cma.j.issn.1674-6902.2026.02.014

Abstract

Abstract:

Objective

To analyze the correlation between the dynamic changes in serum calprotectin (Cal) levels and the prognosis of severe pneumonia (SP).

Methods

Sixty-four patients with severe pneumonia admitted to our hospital from January 2023 to January 2025 were selected as subjects. They were grouped according to prognosis: 42 patients in the observation group, and 22 patients in the control group. Serum Cal levels were measured on admission day 1 (T1), day 3 (T3), and day 7 (T7). ΔQ1 (T3-T1), ΔQ2 (T7-T1), ΔQ1%[(T3-T1)/T1], and ΔQ2%[(T7-T1)/T1] were calculated. Multivariate logistic regression analysis was used to identify factors affecting prognosis. The clinical applicability was evaluated using receiver operating characteristic (ROC) curves and decision curve analysis (DCA).

Results

The neutrophil count [(9.31±1.72) ×10⁹/L vs. (8.12±1.27)×10⁹/L], C-reactive protein (CRP) [(38.36±10.52) mg/L vs. (32.59±9.32) mg/L], and acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) score [(17.53±2.14) points vs. (15.24±2.26) points] in the observation group were higher than those in the control group (P<0.05). The serum Cal in T3 of the observation group [(10.43±1.25) μg/ml vs. (9.25±1.36) μg/ml] and the serum Cal in T7 [(13.83±1.34) μg/ml vs. (10.12±1.78) μg/ml] were higher than those in the control group (P<0.05); the ΔQ2 in the observation group [(8.34 (6.48, 10.03) vs. 4.75 (3.74, 6.45)] and the ΔQ2% [(1.39 (0.90, 2.37) vs. -0.98 (-1.49, -0.59)] were higher than those in the control group (P<0.05). Multivariate Logistic regression showed that neutrophil count (OR=1.069, 95%CI: 1.017~1.124), CRP (OR=1.506, 95%CI: 1.062~2.134), APACHE Ⅱ score (OR=1.318, 95%CI: 1.085~1.600), ΔQ2 (OR=4.358, 95%CI: 2.575~7.374), and ΔQ2% (OR=0.137, 95%CI: 0.053~0.354) were prognostic factors (P<0.05). Receiver operating characteristic (ROC) curve analysis showed that the area under the curve (AUC) for predicting prognosis by neutrophil count, CRP, APACHE Ⅱ score, ΔQ2, and ΔQ2% was 0.677, 0.670, 0.733, 0.661, and 0.750, respectively. The combined prediction AUC was 0.940 (95%CI: 0.891~0.971), with a sensitivity of 90.28% and a specificity of 85.87%. DCA showed that the net benefit difference of the prediction model at the threshold probability of 0.1 to 0.8 was 0.05 to 0.15.

Conclusion

The dynamic detection of serum Cal levels in the early stages of admission is associated with the prognosis of patients with severe pneumonia. Elevated neutrophil count, CRP, APACHE Ⅱ score, ΔQ2, and ΔQ2% are prognostic influencing factors.

Key words: Severe pneumonia, Serum calprotectin, Dynamic change, Decision curve, Prognosis

Jin Zhang, Qiang Ye, Chun Yao, Jinfeng Xu, Lijie Zheng. Correlation analysis of dynamic changes of serum calprotectin level and prognosis in patients with severe pneumonia[J]. Chinese Journal of Lung Diseases(Electronic Edition), 2026, 19(02): 275-281.

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URL: https://zhfbjbzz.cma-cmc.com.cn/EN/10.3877/cma.j.issn.1674-6902.2026.02.014

https://zhfbjbzz.cma-cmc.com.cn/EN/Y2026/V19/I02/275

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References 30

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临床资料	观察组(n＝72)	对照组(n＝92)	t/χ²值	P值
吸烟史[n(%)]	25(34.72)	27(29.35)	0.539	0.463
糖尿病[n(%)]	17(23.61)	13(14.13)	2.429	0.119
高血压[n(%)]	25(34.72)	26(28.26)	0.787	0.375
机械通气时间[d，(±s)]	6.34±1.15	5.97±1.28	1.945	0.054
住院时间[d，(±s)]	12.56±2.47	11.85±2.82	1.716	0.088
实验室指标(±s)
白细胞计数(×10⁹/L)	11.26±2.15	10.94±2.34	0.910	0.364
中性粒细胞计数(×10⁹/L)	9.31±1.72	8.12±1.27	4.915	0.000
淋巴细胞计数(×10⁹/L)	0.88±0.21	0.92±0.25	1.113	0.267
CRP(mg/L)	38.36±10.52	32.59±9.32	3.663	0.000
PCT(μg/L)	0.59±0.13	0.55±0.14	1.890	0.061
IL-6(pg/ml)	16.53±2.48	15.87±2.36	1.728	0.086
TNF-α(pg/ml)	19.32±2.53	18.54±2.74	1.889	0.061
PaO₂(mmHg)	59.74±7.35	60.14±7.24	0.348	0.728
PaCO₂(mmHg)	67.45±5.84	66.78±5.32	0.758	0.450
APACHE Ⅱ[分，(±s)]	17.53±2.14	15.24±2.26	6.635	0.000
CPIS评分[分，(±s)]	7.54±1.24	7.21±1.43	1.581	0.116
病原学类型[n(%)]			0.205	0.651
革兰氏阳性菌	44(61.11)	53(57.61)
革兰氏阴性菌	28(38.89)	39(42.39)
伴有COPD[n(%)]	18(25.00)	13(14.13)	3.113	0.078
合并心衰[n(%)]	9(12.50)	6(6.52)	1.737	0.188

临床资料	观察组(n＝72)	对照组(n＝92)	t/χ²值	P值
吸烟史[n(%)]	25(34.72)	27(29.35)	0.539	0.463
糖尿病[n(%)]	17(23.61)	13(14.13)	2.429	0.119
高血压[n(%)]	25(34.72)	26(28.26)	0.787	0.375
机械通气时间[d，(±s)]	6.34±1.15	5.97±1.28	1.945	0.054
住院时间[d，(±s)]	12.56±2.47	11.85±2.82	1.716	0.088
实验室指标(±s)
白细胞计数(×10⁹/L)	11.26±2.15	10.94±2.34	0.910	0.364
中性粒细胞计数(×10⁹/L)	9.31±1.72	8.12±1.27	4.915	0.000
淋巴细胞计数(×10⁹/L)	0.88±0.21	0.92±0.25	1.113	0.267
CRP(mg/L)	38.36±10.52	32.59±9.32	3.663	0.000
PCT(μg/L)	0.59±0.13	0.55±0.14	1.890	0.061
IL-6(pg/ml)	16.53±2.48	15.87±2.36	1.728	0.086
TNF-α(pg/ml)	19.32±2.53	18.54±2.74	1.889	0.061
PaO₂(mmHg)	59.74±7.35	60.14±7.24	0.348	0.728
PaCO₂(mmHg)	67.45±5.84	66.78±5.32	0.758	0.450
APACHE Ⅱ[分，(±s)]	17.53±2.14	15.24±2.26	6.635	0.000
CPIS评分[分，(±s)]	7.54±1.24	7.21±1.43	1.581	0.116
病原学类型[n(%)]			0.205	0.651
革兰氏阳性菌	44(61.11)	53(57.61)
革兰氏阴性菌	28(38.89)	39(42.39)
伴有COPD[n(%)]	18(25.00)	13(14.13)	3.113	0.078
合并心衰[n(%)]	9(12.50)	6(6.52)	1.737	0.188

Cal水平	观察组(n＝72)	对照组(n＝92)	t/Z值	P值
时相(±s)
T1	5.63±1.72	5.19±1.68	1.642	0.103
T3	10.43±1.25	9.25±1.36	5.771	0.000
T7	13.83±1.34	10.12±1.78	7.018	0.000
动态变化[M(Q₂₅，Q₇₅)]
ΔQ1	4.86(3.46，5.89)	4.16(2.74，5.64)	2.000	0.046
ΔQ2	8.34(6.48，10.03)	4.75(3.74，6.45)	7.404	0.000
ΔQ1%	0.84(0.48，1.40)	0.85(0.42，1.35)	0.593	0.553
ΔQ2%	1.39(0.90，2.37)	0.98(1.49，0.59)	3.978	0.000

Cal水平	观察组(n＝72)	对照组(n＝92)	t/Z值	P值
时相(±s)
T1	5.63±1.72	5.19±1.68	1.642	0.103
T3	10.43±1.25	9.25±1.36	5.771	0.000
T7	13.83±1.34	10.12±1.78	7.018	0.000
动态变化[M(Q₂₅，Q₇₅)]
ΔQ1	4.86(3.46，5.89)	4.16(2.74，5.64)	2.000	0.046
ΔQ2	8.34(6.48，10.03)	4.75(3.74，6.45)	7.404	0.000
ΔQ1%	0.84(0.48，1.40)	0.85(0.42，1.35)	0.593	0.553
ΔQ2%	1.39(0.90，2.37)	0.98(1.49，0.59)	3.978	0.000

自变量	β	标准误	Wald	P值	OR	95%CI
自变量	β	标准误	Wald	P值	OR	下限	上限
中性粒细胞计数	0.067	0.026	6.797	0.009	1.069	1.017	1.124
CRP	0.409	0.178	5.283	0.022	1.506	1.062	2.134
APACHEⅡ评分	0.276	0.099	7.774	0.005	1.318	1.085	1.600
ΔQ2	1.472	0.268	30.076	0.000	4.358	2.575	7.374
ΔQ2%	1.987	0.484	16.868	0.000	0.137	0.053	0.354
常量	17.442	3.257	28.683

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