Toscana virus (TOSV) is an emerging pathogen in the Mediterranean basin where it causes summertime outbreaks of aseptic meningitis and meningoencephalitis. Many aspects of TOSV biology remain unknown including the possible implication of an amplifying mammalian host besides its vector. The three experiments described here were designed to assess the relationship between TOSV and type-I interferon (IFN) response. The main findings were as follows. First, TOSV growth in Vero cells is sensitive to an antiviral state induced by low-dose addition of exogenous IFN beta (IFN-β) (10IU/ml). Second, no IFN-β mRNA or IFN-β was detectable after infection of HeLa and 293T cells by TOSV. Finally, TOSV inhibits IFN-β production induced by Sendaï virus, a well known inducer of IFN-β production. In addition to showing that TOSV can inhibit the IFN-β response, these findings suggest that anti-IFN capability is maintained by regular contact with that of a mammalian host.

Studies with direct-acting antivirals (DAAs) for hepatitis C virus (HCV) monoinfection and HIV coinfection were highlighted at the 2013 Conference on Retroviruses and Opportunistic Infections (CROI). In HCV monoinfected patients, several interferon alfa-sparing, all-oral regimens demonstrated cure rates of greater than 90% with 12 weeks of treatment, including for hard-to-treat patients. Cure rates of 75% were attained in HIV/HCV coinfected patients with the addition of the investigational HCV protease inhibitor (PI) simeprevir to peginterferon alfa and ribavirin. Drug-drug interaction data to inform safe coadminstration of antiretroviral therapy with DAA-based HCV treatment were presented. There was continued emphasis on pathogenesis, management, and prevention of the long-term complications of HIV disease and its therapies, including cardiovascular disease, renal disease, alterations in bone metabolism, and vitamin D deficiency, along with a growing focus on biomarkers to predict development of end-organ disease. Understanding the elevated risk for non-AIDS-defining malignancies in the HIV-infected population and optimal management was a focal point of this year's data. Finally, the conference provided important information on tuberculosis coinfection and cryptococcal meningitis.

The literature reports that neurological complications of childhood respiratory diseases due to respiratory syncytial virus (RSV) fluctuate between 1 and 40% of cases. They mostly involve central apnea - often the first symptom of infection - anoxia, and ischemic brain damage due to severe sudden weakness in infants, and seizures and consciousness disorders more or less associated with focalized neurological deficiency proving an encephalitis lesion. We report the case of brainstem encephalitis in a 7-year-old boy with RSV A nasopharyngitis, with meningitis, positive polymerase chain reaction in cerebrospinal fluid and magnetic resonance imaging (MRI) abnormalities, which was explained by viral replication encephalitis. Based on a literature review, we discuss the main aspects of epidemiology and physiopathology of the main neurological complication of RSV. Most of them have not been fully investigated and only a few articles report encephalitis. As far as central apnea is concerned, an animal experimental hypothesis surprisingly suggests a peripheral mechanism.

AIM:

Because meningitis symptoms are not very specific under the age of 18 months, lumbar puncture (LP) was widely recommended in children presenting a febrile seizure (FS). Recent retrospective studies have challenged this age criterion. In 2011, the American Academy of Pediatrics updated its guidelines for the first episode of simple FS: LP is indicated if signs suggestive of meningitis are present and remains "an option" in case of prior antibiotic treatment or between the age of 6 and 12 months if the child is not properly vaccinated against Haemophilus and Streptococcus pneumoniae. Because the meningitis epidemiology and the vaccination coverage are different, the objective of this study was to evaluate whether these new guidelines were applicable in France.

PATIENTS AND METHODS:

Between 2009 and 2010, we conducted a retrospective single-center study including 157 children aged less than 18 months admitted to the pediatric emergency department (Children's Hospital, Toulouse, France) for their first febrile seizure. The data collected were: type of seizure, knowledge of prior antibiotic treatment, neurological status, signs of central nervous system infection, and biological results (LP, blood cultures).

RESULTS:

Lumbar puncture was performed in 40% of cases (n=63). The diagnosis of meningitis/encephalitis was selected in eight cases: three cases of viral meningitis, three bacterial meningitis (Streptococcus pneumoniae), and two non-herpetic viral encephalitis. The incidence of bacterial meningitis in our study was 1.9%. The risk of serious infection, bacterial meningitis or encephalitis, was increased when there was a complex FS (14% versus 0% with a simple FS, P=0.06). The presence of other suggestive clinical symptoms was strongly associated with a risk of bacterial meningitis/encephalitis (36% in case of clinical orientation versus 0% in the absence of such signs, P<0.001).

DISCUSSION:

All severe clinical presentations were associated with complex FS (prolonged, focal, and/or repeated seizures) and the presence of other suggestive clinical signs (impaired consciousness lasting longer than 1h after the seizure, septic aspect, behavior disorders, hypotonia, bulging fontanel, neck stiffness, petechial purpura). The risk of bacterial meningitis or encephalitis associated with a simple FS and followed by a strictly normal clinical examination is extremely low.

CONCLUSION:

After a simple febrile seizure without any other suggestive signs of meningitis, systematic lumbar puncture is not necessary even in children younger than 18 months. LP remains absolutely indicated if clinical symptoms concentrate on central nervous system infection and should be discussed in case of complex seizures, prior antibiotic treatment, or incomplete vaccination.

Leptospirosis is caused by pathogenic bacteria called leptospires that are transmitted directly or indirectly from animals to humans. It occurs worldwide but is most common in tropical and subtropical areas. It is a potentially serious but treatable disease. Its symptoms may mimic those of a number of other unrelated infections such as influenza, meningitis, hepatitis, dengue, or other viral hemorrhagic fevers. The spectrum of the disease is extremely wide, ranging from subclinical infection to a severe syndrome of multiorgan infection with high mortality. Laboratory diagnosis tests are not always available, especially in developing countries. Numerous tests have been developed, but availability of appropriate laboratory support is still a problem. Direct observation of leptospires by darkfield microscopy is unreliable and not recommended. Isolation of leptospires can take up to months and does not contribute to early diagnosis. Diagnosis is usually performed by serology; enzyme-linked immunosorbent assay and the microscopic agglutination tests are the laboratory methods generally used, rapid tests are also available. Limitation of serology is that antibodies are lacking at the acute phase of the disease. In recent years, several real-time polymerase chain reaction assays have been described. These can confirm the diagnosis in the early phase of the disease prior to antibody titers are at detectable levels, but molecular testing is not available in restricted resources areas.

Enteroviruses (EV) are a common cause of aseptic meningitis in children. Virological diagnosis of EV meningitis is currently based on the detection of the viral genome in the cerebrospinal fluid (CSF). This study attempted to determine the correlation and the temporality of the polymerase chain reaction (PCR) assay in serum and CSF and to evaluate the possibility of diagnosing EV infection only on the serum PCR. The EV genome was sought by RT real-time PCR (Smart Cycler EV Primer and Probe Set(®), Cepheid) in CSF and serum, collected at the same time, for all children who underwent a lumbar puncture for suspected meningitis, between 1 June and 31 July 2010 at the Versailles Hospital. Forty-four patients were included in the study. EV infection was documented for 22 of them. In 10 patients, the EV genome was detected in CSF only; in 3 patients in serum only, and in 9 patients in both. Among patients with acute EV neurological infection, viremic children were significantly younger (1.6months versus 5.8years; P<0.001). Viremia was detected when the serum was sampled within 30h after the beginning of symptoms. These results confirm previous reports of early and transient viremia in young children. This preliminary study shows the limits and added value of EV PCR in serum. It suggests that in some children and under certain conditions (age >3months, clinical and biological compatibility with a viral infection, no previous antibiotic therapy, time from symptom onset to blood sampling <30h, PCR in serum analyzed within 3h), PCR in serum, when positive, is a possible alternative. Therefore, it may be possible to diagnose EV infection without performing a lumbar puncture in a limited number of young children (11.4% of our suspected cases). This study needs to be reinforced by a multicenter study with a broader panel of patients.

Children with cerebrospinal fluid pleocytosis are frequently treated with parenteral antibiotics, but only a few have bacterial meningitis. Although some clinical prediction rules, such as bacterial meningitis score, are of well-known value, the cerebrospinal fluid white blood cells count can be the initial available information. Our aim was to establish a cutoff point of cerebrospinal fluid white blood cell count that could distinguish bacterial from viral and aseptic meningitis. A retrospective study of children aged 29 days to 17 years who were admitted between January 1st and December 31th, 2009, with cerebrospinal fluid pleocytosis (white blood cell≥7μL(-1)) was conducted. The cases of traumatic lumbar puncture and of antibiotic treatment before lumbar puncture were excluded. There were 295 patients with cerebrospinal fluid pleocytosis, 60.3% females, medium age 5.0±4.3 years distributed as: 12.2% 1-3 months; 10.5% 3-12 months; 29.8% 12 months to 5 years; 47.5% >5 years. Thirty one children (10.5%) were diagnosed with bacterial meningitis, 156 (52.9%) viral meningitis and 108 (36.6%) aseptic meningitis. Bacterial meningitis was caused by Neisseria meningitidis (48.4%), Streptococcus pneumoniae (32.3%), other Streptococcus species (9.7%), and other agents (9.7%). cerebrospinal fluid white blood cell count was significantly higher in patients with bacterial meningitis (mean, 4839cells/μL) compared to patients with aseptic meningitis (mean, 159cells/μL, p<0.001), with those with aseptic meningitis (mean, 577cells/μL, p<0.001) and with all non-bacterial meningitis cases together (p<0.001). A cutoff value of 321white blood cell/μL showed the best combination of sensitivity (80.6%) and specificity (81.4%) for the diagnosis of bacterial meningitis (area under receiver operating characteristic curve 0.837). Therefore, the value of cerebrospinal fluid white blood cell count was found to be a useful and rapid diagnostic test to distinguish between bacterial and nonbacterial meningitis in children.

Cerebral malaria, acute bacterial meningitis and viral encephalitis are the main causes of fever and altered consciousness in the tropics. In areas where reliable laboratory testing is unavailable, over diagnosis and misdiagnosis of these conditions is likely. In malaria endemic countries non-malarial contributors to coma may be overlooked, overburdening available resources. The aim of this study is to evaluate the underlying causes of altered mental state in children presenting with fever and coma to tertiary medical facilities in Sudan.Children over one month of age admitted to the emergency departments of three main hospitals in Khartoum with fever and coma were investigated for cerebral malaria, acute bacterial meningitis and Herpes simplex encephalitis during April to November 2011.One hundred and four children presenting with fever and coma were evaluated. Cerebral malaria was clinically suspected in 38 patients and 5 were confirmed. Acute bacterial meningitis was suspected in 63 patients and confirmed in 15. Herpes encephalitis was confirmed in only one case. There were five cases of mixed infection and the remainder were unknown.The clinical diagnoses of cerebral malaria, acute bacterial meningitis and viral encephalitis are unreliable. Further studies to evaluate the underlying causes of coma in febrile Sudanese children are warranted.

This study aimed to test whether C-reactive protein (CRP) measurement could differentiate between different types of meningitis and become a routine test.A prospective study included 140 children admitted to Manipal Teaching Hospital, Pokhara, Nepal, between July 2009 and June 2011. The subjects had a blood test and detailed cerebrospinal fluid (CSF) analysis, including blood and CSF CRP levels.Of those admitted, 31.1% had pyogenic meningitis (PM), 26.2% partially treated meningitis (PPM), 33% viral meningitis (VM), and 9.7% tubercular meningitis (TBM), with 26.4% controls. Organisms were isolated in 12.5% of the cases by blood culture and 25% of cases through CSF culture. Blood CRP was positive in all groups, with the highest values in PM (53.12 ± 28.88 mg/dl) and PPM (47.55 ± 34.34 mg/dl); this was not statistically significant (P = 0.08). The CSF CRP levels were significantly higher (P <0.001) in PM (45.75 ± 28.50 mg/dl) and PPM (23.11 ± 23.98 mg/dl). The sensitivity and specificity of blood CRP was 90.62%, 88.88%, 64.7%, 70% and 32.4%, 30.97%, 24.52%, 26.12% and that of CSF CRP was 96.87%, 66.66%, 20.58%, 10% and 74.73%, 63.71%, 50.94%, 55.35% for PM, PPM, VM and TBM, respectively.Because of its high sensitivity, both CSF CRP and blood CRP can be used to screen for bacterial meningitis (both PM and PPM). CSF CRP screening yielded results with a higher specificity than blood CRP; hence, it can be a supportive test along with CSF cytology, biochemistry, and microbiology for diagnosing meningitis.

Coxsackievirus B3 (CVB3) is a causative agent of viral myocarditis, hepatitis, pancreatitis, and meningitis in humans. The adenosine-uridine (AU)-rich element RNA binding factor 1 (AUF1) is an integral component in the regulation of gene expression. AUF1 destabilizes mRNAs and targets them for degradation by binding to AU-rich elements in the 3' untranslated region (UTR) of mRNAs. The 3'-UTR of the CVB3 genome contains canonical AU-rich sequences, raising the possibility that CVB3 RNA may also be subjected to AUF1-mediated degradation. Here, we reported that CVB3 infection led to cytoplasmic redistribution and cleavage of AUF1. These events are independent of CVB3-induced caspase activation but require viral protein production. Overexpression of viral protease 2A reproduced CVB3-induced cytoplasmic redistribution of AUF1, while in vitro cleavage assay revealed that viral protease 3C contributed to AUF1 cleavage. Furthermore, we showed that knockdown of AUF1 facilitated viral RNA, protein, and progeny production, suggesting an antiviral property for AUF1 against CVB3 infection. Finally, an immunoprecipitation study demonstrated the physical interaction between AUF1 and the 3'-UTR of CVB3, potentially targeting CVB3 genome toward degradation. Together, our results suggest that cleavage of AUF1 may be a strategy employed by CVB3 to enhance the stability of its viral genome.-Wong, J., Si, X., Angeles, A., Zhang, J., Shi, J., Fung, G., Jagdeo, J., Wang, T., Zhong, Z., Jan, E., Luo, H. Cytoplasmic redistribution and cleavage of AUF1 during coxsackievirus infection enhance the stability of its viral genome.