Distinct expression and clinical value of aquaporin 4 in children with hand, foot and mouth disease caused by enterovirus 71.

Brain dysfunction is a prerequisite for critical complications in children with hand, foot, and mouth disease (HFMD). Aquaporin 4 (AQP-4) may be involved in the pathological process of cerebral oedema and injury in children with severe and critical HFMD. This study aimed to assess the association of AQP-4 with the severity of enterovirus 71 (EV71)-associated HFMD. Children with EV71-infected HFMD were divided into a common group (clinical stage 1), a severe group (clinical stage 2), and a critical group (clinical stage 3) according to Chinese guidelines. The levels of AQP-4, interleukin-6 (IL-6), norepinephrine (NE), and neuron-specific enolase (NSE) before and after treatment were tested. Serum AQP-4, IL-6, NE, and NSE levels showed significant differences among the critical, severe, and common groups before and after treatment (P < 0.01). No significant differences in AQP-4 levels in cerebrospinal fluid (CSF) were observed between the critical and severe groups before and after treatment, but the CSF AQP-4 levels in these two groups were higher than those in the common group before treatment (P < 0.01). Serum AQP-4 levels, but not CSF AQP-4 levels, closely correlated with serum IL-6, NE, and NSE levels. These results suggest that the level of AQP-4 in serum, but not in CSF, is a candidate biomarker for evaluating the severity and prognosis of EV71-associated HFMD.

Identification of a new recombinant strain of echovirus 33 from children with hand, foot, and mouth disease complicated by meningitis in Yunnan, China.

BACKGROUND: Hand, foot, and mouth disease (HFMD) is a common childhood disease, which is usually caused by enterovirus A (EV-A) serotypes. Enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) are the main etiologic agents. Multiple serotypes of enterovirus B serotypes (EV-B) have been detected in outbreaks or sporadic cases of HFMD. RESULTS: During HFMD surveillance in Yunnan, China in 2013, two echovirus 33 (E-33) isolates were recovered in cell culture and typed by molecular methods from the cerebrospinal fluid (CSF) and feces of two sporadic cases of HFMD complicated by meningitis. Sequence analysis indicated that the study isolates, YNK35 and YNA12, formed an independent branch, and belonged to E-33 genotype H. Recombination analysis indicated multiple recombination events in the genomic sequence of isolate YNK35. The recombination mainly occurred in the non-structural coding region of P2 and P3, and involved intra-species recombination of species B. CONCLUSION: In this study, the complete sequences of two E-33 isolates were determined. This is the first report of severe HFMD associated with E-33 in Yunnan China, and it enriches the number of full-length genome sequences of E-33 in the GenBank database.

In enterovirus 71 encephalitis with cardio-respiratory compromise, elevated interleukin 1ß, interleukin 1 receptor antagonist, and granulocyte colony-stimulating factor levels are markers of poor prognosis.

BACKGROUND: Enterovirus 71 (EV71) causes large outbreaks of hand, foot, and mouth disease (HFMD), with severe neurological complications and cardio-respiratory compromise, but the pathogenesis is poorly understood. METHODS: We measured levels of 30 chemokines and cytokines in serum and cerebrospinal fluid (CSF) samples from Malaysian children hospitalized with EV71 infection (n = 88), comprising uncomplicated HFMD (n = 47), meningitis (n = 8), acute flaccid paralysis (n = 1), encephalitis (n = 21), and encephalitis with cardiorespiratory compromise (n = 11). Four of the latter patients died. RESULTS: Both pro-inflammatory and anti-inflammatory mediator levels were elevated, with different patterns of mediator abundance in the CSF and vascular compartments. Serum concentrations of interleukin 1ß (IL-1ß), interleukin 1 receptor antagonist (IL-1Ra), and granulocyte colony-stimulating factor (G-CSF) were raised significantly in patients who developed cardio-respiratory compromise (P = .013, P = .004, and P < .001, respectively). Serum IL-1Ra and G-CSF levels were also significantly elevated in patients who died, with a serum G-CSF to interleukin 5 ratio of >100 at admission being the most accurate prognostic marker for death (P < .001; accuracy, 85.5%; sensitivity, 100%; specificity, 84.7%). CONCLUSIONS: Given that IL-1ß has a negative inotropic action on the heart, and that both its natural antagonist, IL-1Ra, and G-CSF are being assessed as treatments for acute cardiac impairment, the findings suggest we have identified functional markers of EV71-related cardiac dysfunction and potential treatment options.

Molecular epidemiology of the 2005 enterovirus 71 outbreak in central Taiwan.

BACKGROUND: Since 1998, Taiwan has experienced annual outbreaks of enterovirus 71 (EV71) nationwide. The area around Taichung City experienced a particularly large outbreak in 2005, after which EV71 disappeared for 2 y before re-emerging in 2008. Here we present the clinical, genotypic, and epidemiological baseline data for the 2005 Taichung outbreak. METHODS: Throat swab, stool and cerebrospinal fluid samples were collected and stored in viral transport medium. Samples were tested by reverse-transcriptase polymerase chain reaction and viral culture. Epidemiological, laboratory, and clinical data were extracted from medical record reviews. A total of 27 virus isolates were selected for phylogenetic analysis. RESULTS: Confirmed phylogenetic results of the viruses were separated into 5 groups. The 5'-UTR regions served as a focus for investigating genetic relationships among the 27 EV71 isolates, all of which belonged to a distinct clade in the C4 genotype. Most of the strains belonged to 5 observed epidemic groups. CONCLUSION: In conclusion, the 2005 outbreak in central Taiwan was caused by divergent EV71 strains belonging to the C4 genotype.

Characterization of inflammatory cytokine profiles in cerebrospinal fluid of hand, foot, and mouth disease children with enterovirus 71-related encephalitis in Hangzhou, Zhejiang, China.

Enterovirus 71 (EV71) is an important etiological agent of hand, foot, and mouth disease (HFMD), which can also lead to severe neurological complications (eg, encephalitis) in young children. Although a series of reports on EV71 infection have been published, the pathogenic mechanism of EV71 infection is still not fully understood.We evaluated the cerebrospinal fluid (CSF) levels of the inflammatory cytokines interleukin (IL)-8, IL-1ß, IL-6, IL-10, tumor necrosis factor (TNF)-α, and IL-12p70 in 88 children with EV71-related encephalitis and 19 children with febrile convulsion (FC) with the use of commercial cytometric bead array kits.The levels of IL-8, IL-1ß, IL-6, and IL-10 in CSF were significantly higher in encephalitis group when compared with those observed in FC group, while no significant changes were noted in the levels of TNF-α and IL-12p70. In addition, significant and positive correlations among CSF IL-8, IL-1ß, IL-6, and IL-10 were observed in encephalitis group. Furthermore, receiver operator characteristic analysis determined a cut-off value of 10.62 pg/mL for IL-6 to discriminate encephalitis patients from FCs with the sensitivity and specificity of 89.8% and 84.2%, respectively. Moreover, logistic regression analyses revealed that IL-6 was an independent predictor of EV71-related encephalitis (odds ratio = 23.241, P < .001).Our results indicate that 4 inflammatory cytokines (IL-8, IL-1ß, IL-6, and IL-10) play important roles in the pathogenesis of EV71 infection. IL-6 may be used for the evaluation of EV71-related encephalitis and as a potential therapy candidate for EV71 infection.

Detection and quantification of enterovirus 71 genome from cerebrospinal fluid of an encephalitis patient by PCR applications.

Enterovirus 71 (EV71) is one of the causative agents of hand, foot, and mouth disease (HFMD) and is known to cause encephalitis, but several reports have identified EV71 in cerebrospinal fluid (CSF). We detected EV71 in CSF from a 20-month-old infant. The patient was diagnosed with brainstem encephalitis associated with HFMD. The clinical features of the patient were high fever (39.1C) and myoclonic jerks, and magnetic resonance imaging of the brain showed a bright signal area around the 4th ventricle. From a nasopharyngeal swab and rectal swab, EV71 was detected using reverse transcription (RT)-nested polymerase chain reaction (PCR). From CSF, the EV71 genome was identified using pan-enterovirus RT-nested PCR and sequencing. By real-time PCR, the nasopharyngeal swab, rectal swab, and CSF contained 1.8 x 10(4), 9.8 x 10(4), and 1.8 x 10 copies of the EV71 genome/microL, respectively. The enterovirus could only be isolated by cell culture from the rectal swab, and it was identified by a neutralization test using EV71-specific antiserum. RT-nested PCR and real-time PCR are considered to be sensitive tools for EV71 diagnosis in CSF.

Case report: Features of hand, foot and mouth disease in neonates.

RATIONALE: Hand, foot and mouth disease (HFMD) is caused by enterovirus. The virus may exist in secretions. PATIENT CONCERNS: Five neonates had symptoms of fever and maculopapular rashes involving face, trunk, breech, arms, and legs, especially scattering on palms and feet. Blood, oropharyngeal fluid, urine, and cerebrospinal fluid (CSF) samples were collected and detected for further diagnoses with the consent of the infants' parents. Some of them suffered aseptic meningitis. DIAGNOSES: They were diagnosed as HFMD with CSF enterovirus positive. INTERVENTIONS: All of them continued breastfeed. Water bag was used during the pyrogenic stage. Antibiotics were administrated at first and withdrawn as soon as possible. OUTCOMES: None of them developed into brainstem encephalitis or pulmonary edema and they all recovered well. LESSONS: HFMD is more common in neonates than it has been thought. Enterovirus may exist in neonatal CSF and cause CSF cell to increase similar to purulent meningitis. Medical history, physical examination, and CSF enterovirus detection are important in making correct diagnosis. Unlike bacterial infection, HFMD is a self-limited disease. Once HFMD is determined and bacterial infection is ruled out, antibiotics should be avoided.

Pulmonary and central nervous system pathology in fatal cases of hand foot and mouth disease caused by enterovirus A71 infection.

In the past 17 years, neurological disease associated with enterovirus A71 (EV-A71) has increased dramatically in the Asia-Pacific region with a high fatality rate in young infants, often due to pulmonary oedema, however the mechanism of this oedema remains obscure. We analysed the brainstem, heart and lungs of 15 fatal cases of confirmed EV-A71 infection in order to understand the pathophysiological mechanism of death and pulmonary oedema. In keeping with other case studies, the main cause of death was neurogenic pulmonary oedema. In the brainstem, 11 cases showed inflammation and all cases showed parenchymal inflammation with seven cases showing moderate or severe clasmatodendrosis. No viral antigen was detected in sections of the brainstem in any of the cases. All fatal cases showed evidence of pulmonary oedema; however, there was absence of direct pulmonary viral damage or myocarditis-induced damage and EV-A71 viral antigen staining was negative. Though there was no increase in staining for Na/K-ATPase, 11 of the 15 cases showed a marked reduction in aquaporin-4 staining in the lung, and this reduction may contribute to the development of fatal pulmonary oedema.