Association of serum 25-(OH) D levels with severe enterovirus 71 related children with hand, foot and mouth disease

Objective To investigate the association of serum 25-(OH) D levels with severity of children with enterovirus 71 (EV71) related hand, foot and mouth disease (HFMD) and to predict the clinical value of 25-(OH) D in severe HFMD of type EV71. Methods A total of 255 children with EV71 HFMD admitted to Xi’an Children’s Hospital from January 2017 to December 2018 were selected as case group, including 150 mild cases (mild group) and 105 severe cases (severe group). Meanwhile, 50 healthy children who were randomly selected for physical examination in the same period were selected as control group. Serum 25-(OH) D levels were measured by chemiluminescence. The clinical data of case groups were collected by a retrospective research method, a unified survey and analysis tables were designed, the data of possible influencing factors were recorded. The univariate and multivariate Logistic regression analysis on factors that may affect the conversion of mild HFMDinto severe HFMD were done. The risk factors of mild EV71 type HFMD into severe EV71 type HFMD and the relationship between serum 25-(OH) D level and severe EV71 related HFMD were investigated, respectively. Results The levels of 25-(OH) D between cases with EV71 HFMD and control group [(35.66 ± 11.60) ng/mlvs. (49.63 ± 8.86) ng/ml] were significantly different (t= 8.062,P 15 × 109/L (χ2= 26.616, P 8.3 mmol/L (χ2= 26.616, P 8.3 mmol/L (OR=2.682, P= 0.028), WBC > 15 × 109/L (OR= 2.090,P= 0.019) and 25-(OH) D < 30.88 ng/ml (OR= 3.792,P< 0.001) were all independent risk factors for severe illness, with significant differences. Conclusions 25-(OH) D <30.88 ng/ml is significantly related to the severity of EV71 HFMD and has important predictive value, which is an early warning factor for severity of EV71 HFMD. Key words: Enterovirus 71; Hand, foot and mouth disease; 25-(OH) D; Risk factor