Study On The Correlation Between Serum 25-(OH)D Level And Incidence And Severity Of Community-acquired Pneumonia In Infants

Objective To investigate the association between serum 25-hydroxyvitamin D[25-(OH)D]level and incidence and severity of community-acquired pneumonia(CAP),and to provide reference for the prevention and treatment of CAP in infants.Method A total of 172 infants diagnosed with CAP who were admitted to the First Affiliated Hospital of Bengbu Medical College between January 2018 and May 2019were used as the CAP group,and 50 healthy infants who received health examination in the pediatric outpatient department during the same period were used as the control group.The serum levels of 25-(OH)D were compared between the two groups.All infants from CAP group were classified into adequacy group(88 cases),insufficiency group(54 cases)and deficiency group(30 cases)based on 25-(OH)D level.The differences in serum 25-(OH)D,white blood cell count(WBC),C-reactive Protein(CRP),procalcitonin(PCT),erythrocyte sedimentation rate(ESR),extra-Pulmonary complications and severity of CAP among the three groups were compared,and then statistically analyze the correlation between the levels of 25-(OH)D and WBC,CRP,PCT and ESR in infants with CAP.Results 1.Comparing the CAP group with the control group,the 25-(OH)D deficiency rates were 48.84%and 24.00%,respectively.And the difference was statistically significant(P<0.05).2.There were no statistically significant differences in gender composition,age distribution,delivery methods and feeding methods among the adequacy,insufficiency and deficiency groups(All P>0.05).3.The levels of WBC,PCT,ESR and hospital stay duration in deficiency group were higher than those in adequacy group and insufficiency group.And there were statistically significant differences between the three groups(All P<0.05).To be specific,there were statistically significant differences in the levels of WBC between the adequacy group and the insufficiency group,the adequacy group and the deficiency group(P<0.001),but there was no statistically significant difference between the insufficiency group and the deficiency group(P>0.05);There were statistically significant differences in the levels of PCT between the adequacy group and the deficiency group,the insufficiency group and the deficiency group(P<0.001),but there was no statistically significant difference between the adequacy group and the insufficiency group(P>0.05);The pairwise the levels of ESR and length of hospitalization among the three groups showed statistically significant differences(P<0.001).While there were no significant differences in the levels of CRP in the adequacy,insufficiency and deficiency groups(P>0.05).4.Spearman rank correlation analysis showed that serum 25-(OH)D level was negatively correlated with WBC and ESR in CAP group(r_s=-0.444,-0.326,P<0.05),and showed no correlation with CRP and PCT level(P>0.05).5.There were statistically significant differences in the incidence of extrapulmonary complications among the three groups(P<0.001),and the difference between the adequacy group and the deficiency group,the insufficiency group and the deficiency group were statistically significant(All P<0.05),but there was no significant difference between the adequacy group and the insufficiency group(P>0.05).6.Among the 44 cases with severe CAP,14 cases(31.81%)had disturbance of consciousness,38 cases(86.36%)had cyanosis,16 cases(36.36%)had high fever,9cases(20.45%)had severe imaging manifestations,and 28 cases(63.63%)had poor general conditions.There was statistically significant difference in the rate of severe cases among the adequacy group,insufficiency group and deficiency group(P<0.001),and the pair comparison was statistically significant(All P<0.05),but there were no statistically significant differences in the distribution of severe cases among the three groups(P>0.05).Conclusions 1.The levels of vitamin D in infants with CAP were lower than those in healthy infants,and the deficiency rate of vitamin D was higher than that in healthy infants,suggesting that vitamin D was related to the occurrence of CAP.2.Inflammatory indexes of infants with vitamin D deficiency are higher than those of infants with vitamin D sufficiency,suggesting that vitamin D level is related to the occurrence and development of CAP.3.When vitamin D levels are lacking,the infants with CAP have a higher probability of extra-Pulmonary organs involvement,mainly gastrointestinal damage.4.Infants with vitamin D deficiency have an increased risk of developing or progressing to severe Pneumonia.Among them,the majority of severe cases have cyanosis symptoms,while the imaging manifestations of severe pneumonia were relatively few.