A case-control study of risk factors for severe hand-foot-mouth disease in Yuxi, China, 2010-2012

The CXCL10/CXCR3 Axis Promotes Disease Pathogenesis in Mice upon CVA2 Infection

Coxsackievirus A2 (CVA2) is an emerging pathogen that results in hand-foot-and-mouth disease (HFMD) outbreaks. Systemic inflammatory response and central nervous system inflammation are the main pathological features of fatal HFMD. However, the immunopathogenesis of CVA2 infection is poorly understood. We first detected the transcriptional levels of 81 inflammation-related genes in neonatal mice with CVA2 infection. Remarkably, CVA2 induced higher expression of chemokine (C-X-C motif) ligand 10 (CXCL10) in multiple organs and tissues. CXCL10 acts through its cognate receptor chemokine (C-X-C motif) receptor 3 (CXCR3) and regulates immune responses. CXCL10/CXCR3 activation contributes to the pathogenesis of many inflammatory diseases. Next, we found CXCL10 and CXCR3 expression to be significantly elevated in the organs and tissues from CVA2-infected mice at 5 days postinfection (dpi) using immunohistochemistry (IHC). To further explore the role of CXCL10/CXCR3 in CVA2 pathogenesis, an anti-CXCR3 neutralizing antibody (αCXCR3) or IgG isotype control antibody was used to treat CVA2-infected mice on the same day as infection and every 24 h until 5 dpi. Our results showed that αCXCR3 therapy relieved the clinical manifestations and pathological damage and improved the survival rate of CVA2-infected mice. Additionally, αCXCR3 treatment reduced viral loads and reversed the proinflammatory cytokine (interleukin 6 [IL-6], tumor necrosis factor alpha [TNF-α], and IL-1β) expression, apoptosis, and inflammatory cell infiltration induced by CVA2. Collectively, our study presents evidence for the involvement of the CXCL10/CXCR3 axis in CVA2 pathogenesis. The activation of CXCL10/CXCR3 contributes to CVA2 pathogenesis by inducing apoptosis, proinflammatory cytokine expression, and inflammatory cell infiltration, which can be reversed by αCXCR3 therapy. This study provides new insight into the pathogenesis of HFMD, which has an important guiding significance for the treatment of HFMD. IMPORTANCE Systemic inflammatory response and central nervous system inflammation are the main pathological features of fatal HFMD cases. We detected the expression of 81 inflammation-related genes and found higher expression of CXCL10 in CVA2-infected mice. Next, we confirmed CXCL10/CXCR3 activation using immunohistochemistry and found that anti-CXCR3 neutralizing antibody (αCXCR3) therapy could relieve the clinical manifestations and pathological damage and improve the survival rate of CVA2-infected mice. Additionally, αCXCR3 treatment reduced viral loads and reversed the proinflammatory cytokine (IL-6, TNF-α, and IL-1β) expression, apoptosis, and inflammatory cell infiltration induced by CVA2. Collectively, our study presents the first evidence for the involvement of the CXCL10/CXCR3 axis in CVA2 pathogenesis. The activation of CXCL10/CXCR3 contributes to CVA2 pathogenesis via inducing apoptosis, proinflammatory cytokine expression, and inflammatory cell infiltration, which can be reversed by αCXCR3 therapy. This study provides new insight into the pathogenesis of HFMD, which has an important guiding significance for the treatment of HFMD.

The Risk Factors of Acquiring Severe Hand, Foot, and Mouth Disease: A Meta-Analysis

Objectives

The incidence of severe hand, foot, and mouth disease (HFMD) is not low, especially in mainland China in almost every year recently. In this study, we conducted a meta-analysis to generate large-scale evidence on the risk factors of severe HFMD to provide suggestions on prevention and controlling.

Methods

PubMed, Web of Science, Embase, Cochrane Library, China National Knowledge Infrastructure (CNKI), and Wanfang (Chinese) were searched to identify relevant articles. All analyses were performed using Stata 14.0.

Results

We conducted a meta-analysis of 11 separate studies. Fever (odds ratio (OR) 7.396, 95% confidence interval (CI) 3.565–15.342), fever for more than 3 days (OR 5.773, 95% CI 4.199–7.939), vomiting (OR 6.023, 95% CI 2.598–13.963), limb trembling (OR 42.348, 95% CI 11.765–152.437), dyspnea (OR 12.869, 95% CI 1.948–85.017), contact with HFMD children (OR 5.326, 95% CI 1.263–22.466), rashes on the hips (OR 1.650, 95% CI 1.303–2.090), pathologic reflexes (OR 3057.064, 95% CI 494.409–19000), Lethargy (OR 31.791, 95% CI 3.369–300.020), convulsions (OR 23.652, 95% CI 1.973–283.592), and EV71 infection (OR 9.056, 95% CI 4.102–19.996) were significantly related to the risk of severe HFMD. We did not find an association between female sex (OR 0.918, 95% CI 0.738–1.142), scatter-lived children (OR 1.347, 95% CI 0.245–7.397), floating population (OR 0.847, 95% CI 0.202–3.549), rash on the hands (OR 0.740, 95% CI 0.292–1.874), rash on the foot (OR 0.905, 95% CI 0.645–1.272), the level of the clinic visited first (below the country level) (OR 5.276, 95% CI 0.781–35.630), breast feeding (OR 0.523, 95% CI 0.167–1.643), and the risk of severe HFMD.

Conclusions

Fever, fever for more than 3 days, vomiting, limb trembling, dyspnea, contact with HFMD children, rashes on the hips, pathologic reflexes, lethargy, convulsions, and EV71 infection are risk factors for severe HFMD.

Risk factors for death in children with critical and severe hand-foot-and-mouth disease in Chongqing, China: An observational study

Hand-foot-and-mouth disease (HFMD) is a common childhood infection that may lead to serious complications and even death. Globally, epidemics of HFMD are increasing each year, especially in China. This study aimed to identify risk factors for death in children with critical and severe HFMD in Chongqing, China.We performed an observational study involving patients with critical and severe HFMD admitted to the Children's Hospital of Chongqing Medical University from January 2009 to December 2016. Overall, 179 patients aged 2 months to 16 years, were included; 127 died (non-survival group) and 52 survived (survival group); the case-fatality rate was 70.94%. Data comprising demographic characteristics, clinical symptoms and signs, and laboratory findings were collected. Non-conditional logistic regression analysis was performed to determine the risk factors for death.Univariate analysis showed that sex, coma, light-reflex insensitivity, pulmonary rales, pulmonary edema or hemorrhage, cold extremities, tachycardia, hypotension, white blood cell count, blood glucose concentration, serum lactate level, creatine kinase-MB isoenzyme level, and acidosis were associated with death (P < .05). Logistic regression analysis identified female sex (odds ratio [OR] 9.6, 95% confidence interval [CI] 3.0-30.2), light-reflex insensitivity (OR 4.4, 95% CI 1.4-13.1), tachycardia (OR 1.05, 95% CI 1.03-1.07), and higher serum lactate levels (OR 1.14, 95% CI 1.19-1.69) as independent risk factors; and longer onset-to-hospitalization time (OR 0.43, 95% CI 0.28-0.66) as an independent protective factor for death in children with critical and severe HFMD.Female sex, light-reflex insensitivity, tachycardia, and higher serum lactate level are potential independent risk factors; and longer onset-to-hospitalization time is possibly an independent protective factor for death in patients with critical and severe HFMD.

Risk factors for neurogenic pulmonary edema in patients with severe hand, foot, and mouth disease: A meta-analysis

OBJECTIVE

To investigate the risk factors for neurogenic pulmonary edema (NPE) in patients with severe hand, foot, and mouth disease (HFMD) and to provide evidence for the prevention and treatment of NPE.

METHODS

Several databases were searched (from inception to 2017) to identify case-control studies on risk factors for NPE among patients with severe HFMD. Data were analyzed via meta-analysis. The combined odds ratio (OR) and 95% confidence interval (CI) were calculated using fixed-effects and random-effects models, and a sensitivity analysis and evaluation of publication bias was also performed.

RESULTS

A total of 14 studies involving 557 cases (severe HFMD with NPE) and 1450 controls (severe HFMD) were included. Results for the categorical variables were as follows: hyperglycemia (OR 10.25, 95% CI 4.82-21.76), tachycardia (OR 6.21, 95% CI 3.02-12.75), hypertension (OR 3.79, 95% CI 2.90-4.95), respiratory rhythm abnormality (OR 7.86, 95% CI 2.46-25.12), drowsiness (OR 8.11, 95% CI 4.26-15.44), vomiting (OR 8.96, 95% CI 3.83-20.96), limb tremors (OR 8.96, 95% CI 3.83-20.96), atypical rash (OR 4.27, 95% CI 2.83-6.45). No significant publication bias was found for the different factors.

CONCLUSIONS

Drowsiness ranks first among risk factors for NPE in children with severe HFMD, followed by vomiting, tachycardia, hypertension, breathing rhythm changes, limb tremors, atypical rash, and hyperglycemia.

Risk factors for severe hand foot mouth disease in Singapore: a case control study

Background

Hand foot mouth disease (HFMD) is a common childhood infection that can potentially lead to serious complications. The aim of this study is to identify risk factors of acquiring severe HFMD in our population.

Methods

We performed a case control study using patients admitted to our hospital from August 2004 to July 2014. Cases were patients with severe HFMD disease while controls were age-matched patients obtained from the same year, in a 2:1 ratio. Data comprising demographic characteristics, clinical symptoms and signs, and lab findings were collected. Conditional univariable logistic regression was performed to determine risk factors for severe disease.

Results

A total of 24 cases of severe HFMD were identified and matched with 48 controls. Seventeen (70.8 %) cases had central nervous system complications. Seven (29.2 %) had cardiovascular complications without evidence of myocarditis. One patient died of encephalitis. The overall mortality of severe disease is 4 %. Evidence of hypoperfusion, seizure, altered mentation, meningeal irritation, tachycardia, tachypnea, raised absolute neutrophil count and EV-A71 (Enterovirus A71) positivity were significantly associated with a severe course of HFMD.

Conclusion

In managing children with HFMD, physicians should consider these factors to help identify patients at risk for severe disease.

EV71 infection correlates with viral IgG preexisting at pharyngo-laryngeal mucosa in children

Enterovirus 71 (EV71) infection causes severe central nervous system damage, particularly for children under the age of 5 years old, which remains a major public health burden worldwide. Clinical data released that children may be repeatedly infected by different members in enterovirus and get even worsen. Mucosa, especially epithelium of alimentary canal, was considered the primary site of EV71 infection. It has been elusive whether the preexsiting viral antibody in mucosa plays a role in EV71 infection. To answer this question, we respectively measured viral antibody response and EV71 RNA copy number of one hundred throat swab specimens from clinically confirmed EV71-infected children. The results released that low-level of mucosal IgG antibody against EV71 broadly existed in young population. More importantly, it further elucidated that the children with mucosal preexsiting EV71 IgG were prone to be infected, which suggested a former viral IgG mediated enhancement of viral infection in vivo.