Functional EEG network analysis in schizophrenia: Evidence of larger segregation and deficit of modulation.

OBJECTIVE: Higher mental functions depend on global cerebral functional coordination. Our aim was to study fast modulation of functional networks in schizophrenia that has not been previously assessed. METHODS: Graph-theory was used to analyze the electroencephalographic (EEG) activity during an odd-ball task in 57 schizophrenia patients (18 first episode patients, FEPs) and 59 healthy controls. Clustering coefficient (CLC), characteristic path length (PL) and small-worldness (SW) were computed at baseline ([-300 0] ms prior to stimulus delivery) and response ([150 450] ms post-stimulus) windows. Clinical and cognitive assessments were performed. RESULTS: CLC, PL and SW showed a significant modulation between baseline and response in controls but not in patients. Patients obtained higher CLC and SW at baseline, lower CLC and higher PL at response, and diminished modulation of CLC and SW as compared to controls. In patients, CLC and SW modulation were inversely associated to cognitive performance in executive tasks and directly associated to working memory. Similar patterns were observed in FEPs. CLC and SW during the baseline were inversely associated to their respective modulation magnitudes. CONCLUSIONS: Our results are coherent with a hyper-segregated network at baseline (higher CLC) and a decreased modulation of the functional connectivity during cognition in schizophrenia.

A follow-up urine sample has limited value after treatment for urinary tract infection in children.

INTRODUCTION: A routine follow-up urine sample (FUS) in the form of a midstream urine sample (MSU) is recommended after treatment for urinary tract infection (UTI) according to the Danish Paediatric Society (DPS) and "Lægehåndbogen" published by Danish Regions. We studied the effect of FUS with a focus on patients without symptoms at the time of FUS. METHODS: Consecutive patients below 16.0 years treated for upper or lower UTI from 1 January 2009 to 31 December 2009 at Hvidovre Hospital in accordance with the guidelines of the department and the DPS. All patients were asked to provide a FUS within 21 days. RESULTS: A total of 87 patients were treated for upper UTI: 59 girls and 28 boys, the median age was 1.1 year (range: 0.1-15.6 years); and 42 girls were treated for lower UTI, their median age was 8.2 years (range: 2.5-15.3 years). After treatment, the risk of a UTI was 0% (0/87) after upper UTI versus 19% (8/42) after lower UTI (Fisher's exact test (FE), p < 0.0001). Among those without symptoms at FUS, the risk of a UTI was 0% (0/75) (95% confidence interval (CI): 0-4.9%) after upper UTI versus 4% (1/26) (95% CI: 0.1-19.6%) after lower UTI (FE, p = 0.2754). The cost of requesting a FUS in patients without symptoms was 166 euro after treatment for upper UTI and 66 euro after treatment of lower UTI. CONCLUSION: We do not recommend a FUS after treatment for UTI as the 95% CI of risk of missing UTI after treatment for upper UTI was below 5%. This strategy will save the patients/families and the health-care system. However, if a child has symptoms after treatment for UTI, it must be examined. FUNDING: not relevant. TRIAL REGISTRATION: The study was approved by the Danish Data Protection Agency (J. no. 2007-58-0015).

Increase in brain-derived neurotrophic factor in first episode psychotic patients after treatment with atypical antipsychotics.

Some preclinical and postmortem studies suggest that the effects of atypical antipsychotics could be mediated by brain-derived neurotrophic factor (BDNF). Olanzapine is an atypical antipsychotic with shown efficacy in psychosis treatment. The aim of this study was to compare plasma BDNF levels at baseline and after 1 year of olanzapine treatment in 18 drug-naive patients who experienced a first psychotic episode with those of 18 healthy control participants matched by age, sex, and socioeconomic level. Plasma BDNF levels were measured in patients at the index episode and at 1, 6, and 12 months of follow-up using an enzyme-linked immunosorbent assay. Symptoms and functioning of patients and controls were assessed with the Positive and Negative Symptom Scale and Global Assessment of Function Scale. BDNF levels of patients at onset were significantly lower than controls but increased toward control values during olanzapine treatment. There was a significant positive correlation between BDNF levels and functioning (Global Assessment of Function Scale). BDNF levels were also negatively correlated with positive symptoms, but not with negative symptoms or general psychopathology. Results suggest that olanzapine can offset the low BDNF levels at the onset of first psychotic episodes, and improving psychotic symptoms. The increase in BDNF levels may be its mechanism of action in improving positive symptoms.

Depersonalization in patients with schizophrenia spectrum disorders, first-degree relatives and normal controls.

BACKGROUND: Depersonalization occurs in healthy individuals and across a broad range of psychiatric patients. Data on depersonalization in persons linked to patients through genetics, environment or education are scarce. Due to their higher risk of developing psychosis, first-degree healthy relatives might show differences with the general population. This study examines depersonalization in patients with schizophrenia or schizophrenia spectrum disorders, their first-degree healthy relatives and normal controls. METHODS: The Cambridge Depersonalization Scale was used to measure depersonalization in a sample of 147 clinically stable patients with schizophrenia or schizophrenia spectrum disorders, 73 first-degree relatives with no psychiatric history and 172 healthy controls. Mixed effect models were used to account for both the familial structure of the data and the effect of sociodemographic characteristics. RESULTS: Patients obtained higher scores than relatives and controls for frequency and duration of depersonalization experiences, number of items responded positively and total depersonalization, while first-degree relatives obtained lower scores than patients and controls for all these characteristics. CONCLUSIONS: First-degree relatives of patients reported fewer episodes of depersonalization, which were less intense and of shorter duration, than healthy controls. This finding might be related to a protection mechanism that keeps first-degree relatives away from near-psychotic experiences. The nature of such a mechanism remains to be discovered.

Meningoencefalitis con afección de cerebelo asociada a neumonía por Coxiella burnetii / Meningoencephalitis with cerebellar involvement associated with Coxiella burnetti pneumonia

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