B-type brain natriuretic peptide as a measure of the severity of hand-foot-mouth disease: a case-control study

BACKGROUND: Hand-foot-mouth disease (HFMD) is an acute infectious disease caused by enteroviruses, and HFMD complicated by cardiopulmonary failure has a high mortality. B type natriuretic peptide (BNP) is widely applied in monitoring cardiovascular disorders, and thus, we investigated whether this index was associated with the severity of HFMD and the outcome in severe HFMD. METHODS: Serum BNP, lactate, and glucose levels as well as white blood cell (WBC) count, PaO(2)/FiO(2), and cardiac output (CO) were analyzed in the 83 enrolled HFMD patients according to different conditions (common, severe, and critical; with and without complication; and survivors and non-survivors). The control group consisted of 29 patients with respiratory tract infections. RESULTS: No significant differences in CO were observed between the groups. Serum lactate, glucose, BNP, and WBC levels in the critical group were significantly higher than those in the severe, common, and control groups (p < 0.01 or 0.05). The PaO(2)/FiO(2) ratio was significantly lower in the critical group (214.286 ± 154.346) than in the other groups. According to logistic regression analysis, the areas under the curve for serum BNP, glucose, and PaO(2)/FiO(2) of the patients with complications were 0.774, 0.738, and 0.75, respectively. Moreover, the BNP level was significantly higher in HFMD patients with complications and non-survivors. CONCLUSION: Our findings indicate that BNP could be a biochemical indicator for severe (critical) HFMD and used for prognosis in terms of complications and death. Combined with Glu and PaO(2)/FiO(2) and clinical symptoms of HFMD, the value of BNP as an indicator became more precise and specific. Our results may provide another valuable, objective biochemical indicator for severe HFMD. TRIAL REGISTRATION NUMBER: ChiCTR-DDT-14004576. Name of registry: Chinese Clinical Trial Registry. Date of registration: 2014–09-21.