Norovírus Associated Encephalopathy

clinical presentation is self limited. It is classified into five groups (genogroups I through V). There are numerous reports of neurologic complications, namely afebrile seizures, but only two reports of associated encephalopathy. Case Report: A 12 month old girl with previous history of a pneumonia treated with amoxicillin-clavulanic acid and clarythromycin, presented in our emergency department with strabismus, ataxia for 3 days, later associated with vomiting and diarrhea. On admission she had ataxia and an episode of strabismus, but her later neurologic exam was normal. Laboratory data revealed: 10,9 g/dL hemoglobin, 11.200/μL leukocytes, 29,1% neutrophils and 65,2% lymphocytes, 488.000/μL platelets and negative CRP. The brain MRI showed middle ear, maxillary sinus and ethmoidal opacification, with no other abnormalities. During the first day of admission she had a tonic (?) seizure for 20 minutes. CSF analysis showed 5,6 cells/μL, 100% lymphocytes, 80 mg/dL glucose and 154,1 mg/dL protein. The EEG revealed short duration paroxystic activity located to the vertex. She was treated with acyclovir, ciprofloxacin, cefthriaxone and phenytoin. Her symptoms resolved by the third day of admission. Blood samples were tested for numerous pathogens, including serology for Borrelia, which was positive for IgG but negative for IgM. Fecal sample analysis revealed positive PCR for norovirus, although it was negative in CSF samples. IL-6 was measured in the CSF and was negative (5,8 pg/mL). She had a history of recurrent otitis media and pernieal candidiasis, which led to a detailed immune function study, which showed Immunology tests revealed diminished IgA (< 0,244 g/L) and absent antibody response to vaccinations. Since she was only 13 months old when she was tested, only follow up will determine the relevance of these values. Follow up at two years of age showed no delays and a normal development. Conclusion: Norovirus encephalitis is a rare entity, although gastrointestinal infection with this agent is relatively common. Here we present a case of a probable norovirus associated encephalopathy, although PCR for norovirus was negative in CSF samples and there was no CSF cytokine increase. It was not associated with adverse neurologic outcome and so far her development is normal, unlike the evolution described in previous case reports.

The Role of the Humoral Immune Response in the Molecular Evolution of the Envelope C2, V3 and C3 Regions in Chronically HIV-2 Infected Patients

BACKGROUND: This study was designed to investigate, for the first time, the short-term molecular evolution of the HIV-2 C2, V3 and C3 envelope regions and its association with the immune response. Clonal sequences of the env C2V3C3 region were obtained from a cohort of eighteen HIV-2 chronically infected patients followed prospectively during 2-4 years. Genetic diversity, divergence, positive selection and glycosylation in the C2V3C3 region were analysed as a function of the number of CD4+ T cells and the anti-C2V3C3 IgG and IgA antibody reactivity RESULTS: The mean intra-host nucleotide diversity was 2.1% (SD, 1.1%), increasing along the course of infection in most patients. Diversity at the amino acid level was significantly lower for the V3 region and higher for the C2 region. The average divergence rate was 0.014 substitutions/site/year, which is similar to that reported in chronic HIV-1 infection. The number and position of positively selected sites was highly variable, except for codons 267 and 270 in C2 that were under strong and persistent positive selection in most patients. N-glycosylation sites located in C2 and V3 were conserved in all patients along the course of infection. Intra-host variation of C2V3C3-specific IgG response over time was inversely associated with the variation in nucleotide and amino acid diversity of the C2V3C3 region. Variation of the C2V3C3-specific IgA response was inversely associated with variation in the number of N-glycosylation sites. CONCLUSION: The evolutionary dynamics of HIV-2 envelope during chronic aviremic infection is similar to HIV-1 implying that the virus should be actively replicating in cellular compartments. Convergent evolution of N-glycosylation in C2 and V3, and the limited diversification of V3, indicates that there are important functional constraints to the potential diversity of the HIV-2 envelope. C2V3C3-specific IgG antibodies are effective at reducing viral population size limiting the number of virus escape mutants. The C3 region seems to be a target for IgA antibodies and increasing N-linked glycosylation may prevent HIV-2 envelope recognition by these antibodies. Our results provide new insights into the biology of HIV-2 and its relation with the human host and may have important implications for vaccine design.

Evolution of the Human Immunodeficiency Virus Type 2 Envelope in the First Years of Infection is Associated with the Dynamics of the Neutralizing Antibody Response

Background: Differently from HIV-1, HIV-2 disease progression usually takes decades without antiretroviral therapy and the majority of HIV-2 infected individuals survive as elite controllers with normal CD4+ T cell counts and low or undetectable plasma viral load. Neutralizing antibodies (Nabs) are thought to play a central role in HIV-2 evolution and pathogenesis. However, the dynamic of the Nab response and resulting HIV-2 escape during acute infection and their impact in HIV-2 evolution and disease progression remain largely unknown. Our objective was to characterize the Nab response and the molecular and phenotypic evolution of HIV-2 in association with Nab escape in the first years of infection in two children infected at birth. Results: CD4+ T cells decreased from about 50% to below 30% in both children in the first five years of infection and the infecting R5 viruses were replaced by X4 viruses within the same period. With antiretroviral therapy, viral load in child 1 decreased to undetectable levels and CD4+ T cells recovered to normal levels, which have been sustained at least until the age of 12. In contrast, viral load increased in child 2 and she progressed to AIDS and death at age 9. Beginning in the first year of life, child 1 raised high titers of antibodies that neutralized primary R5 isolates more effectively than X4 isolates, both autologous and heterologous. Child 2 raised a weak X4-specific Nab response that decreased sharply as disease progressed. Rate of evolution, nucleotide and amino acid diversity, and positive selection, were significantly higher in the envelope of child 1 compared to child 2. Rates of R5-to-X4 tropism switch, of V1 and V3 sequence diversification, and of convergence of V3 to a β-hairpin structure were related with rate of escape from the neutralizing antibodies. Conclusion: Our data suggests that the molecular and phenotypic evolution of the human immunodeficiency virus type 2 envelope are related with the dynamics of the neutralizing antibody response providing further support for a model in which Nabs play an important role in HIV-2 pathogenesis.

Personality, Brain Asymmetry, and Neuroendocrine Reactivity in Two Immune-Mediated Disorders: a Preliminary Report

Development of some immune-mediated disorders may depend on dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis. To explore neuropsychologic mechanisms in relation to the abnormal endocrine reactivity in patients with systemic lupus erythematosus (SLE) and chronic hepatitis C (CHC) we used the corticotropin releasing hormone (CRH) test, the Minnesota Multiphasic Personality Inventory (MMPI), and the Edinburgh Inventory of Manual Preference Inventory (EIMP). Compared to controls, the adrenocorticotrophic hormone (ACTH) response to CRH was reduced in CHC, while SLE presented reduced baseline dehydroepiandrosterone sulfate levels; higher neurotic scores were found in SLE and higher behavior deviant scores in CHC. Peak ACTH levels were a significant factor for the MMPI profile variability, while the manual preference score was a significant factor for the ACTH response. Personality and manual preference contribute to neuroendocrine abnormalities. Different behavioral and neuroimmunoendocrine models emerge for these disorders.

Brain Natriuretic Peptide Levels Predict Morbidity and Mortality in Haemodialysis Patients

Background: Brain natriuretic peptide is a predictor of mortality in multiple cardiovascular diseases but its value in patients with chronic kidney disease is still a matter of debate. Patients and methods: We studied 48 haemodialysis patients with mean age 70.0±13.9 years,62.5% female, 43.8% diabetics, with a mean haemodialysis time of 38.1±29.3 months. To evaluate the role of brain natriuretic peptide as a prognostic factor in this population we performed a two-session evaluation of pre- and postmid-week haemodialysis plasma brain natriuretic peptide concentrations and correlated them with hospitalisation and overall and cardiovascular mortality over a two-year period. Results: There were no significant variations in pre– and post-haemodialysis plasma brain natriuretic peptide concentrations. Pre- and post-haemodialysis brain natriuretic peptide concentrations were significantly greater in patients who died from all causes(p=0.034 and p=0.001, respectively) and from cardiovascular causes (p=0.043 and p=0.001, respectively). Patients who were hospitalised in the two-year study period also presented greater pre- and posthaemodialysis brain natriuretic peptide concentrations(p=0.03 and p=0.036, respectively). Patients with mean brain natriuretic peptide concentrations ≥ 390 pg/mL showed a significantly lower survival at the end of the two-year study period. Conclusion: Brain natriuretic peptide was a good predictor of morbidity and mortality (overall and cardiovascular) in our population.

Different Electroclinical Manifestations of the Epilepsy Associated with Hamartomas Connecting to the Middle or Posterior Hypothalamus

PURPOSE: The epilepsy associated with hypothalamic hamartomas (HHs) has typical clinical, electrophysiologic, and behavioral manifestations refractory to drug therapy and with unfavorable evolution. It is well known that only sessile lesions produce epilepsy, but no correlation has been established between the different types of sessile hamartomas and the diverse manifestations of the epilepsy. We correlate anatomic details of the hamartoma and the clinical and neurophysiologic manifestations of the associated epilepsy. METHODS: HHs of seven patients with epilepsy (ages 2- 25 years) were classified as to lateralization and connection to the anteroposterior axis of the hypothalamus by using high-resolution brain magnetic resonance imaging. We correlated the anatomic classification with the clinical and neurophysiologic manifestations of the epilepsy as evaluated in long-term (24 h) video-EEG recordings. RESULTS: HHs ranged in size from 0.4 to 2.6 cc, with complete lateralization in six of seven patients. Ictal manifestations showed good correlation with the lobar involvement of ictal/interictal EEGs. These manifestations suggest the existence of two types of cortical involvement, one associated with the temporal lobe, produced by hamartomas connected to the posterior hypothalamus (mamillary bodies), and the other associated with the frontal lobe, seen in lesions connecting to the middle hypothalamus. CONCLUSIONS: A consistent clinical and neurophysiologic pattern of either temporal or frontal lobe cortical secondary involvement was found in the patients of our series. It depends on whether the hamartoma connects to the mamillary bodies (temporal lobe cases) or whether it connects to the medial hypothalamus (frontal lobe cases).