Posterior reversible encephalopathy syndrome and cerebral vasculopathy associated with influenza A infection: report of a case and review of the literature.

BACKGROUND AND PURPOSE: Influenza A infection can precipitate encephalopathy, encephalitis, or Reye syndrome with the development of cerebral edema in children and is associated with an increased incidence of stroke in adults. The mechanism of these events is poorly understood. Posterior reversible encephalopathy syndrome (PRES) is seen in association with infection/sepsis, and cerebral vasculopathy has been demonstrated in PRES. We describe a case of PRES that develops in association with influenza A. SUMMARY OF CASE: A normotensive 65-year-old woman presented with altered mentation and nausea in the setting of a viral prodromal illness ultimately confirmed as influenza A. Posterior reversible encephalopathy syndrome developed on the second day after admission. Catheter cerebral angiogram documented vasculopathy in PRES-involved regions with areas of focal vessel dilatation and string-of-bead appearance. CONCLUSIONS: The association between influenza A and PRES with documentation of cerebral vasculopathy suggests a common systemic vascular mechanism behind PRES and influenza-related encephalopathic edema and stroke.

Effect of antipsychotics on pituitary gland volume in treatment-naïve first-episode schizophrenia: a pilot study.

The objective of this study was to examine the effect of antipsychotics on pituitary volume in schizophrenic subjects. Pituitary volumes were measured in 16 patients with schizophrenia at baseline and 12 months after treatment with an antipsychotic medication using magnetic resonance imaging (MRI). A group of 12 healthy controls was evaluated at baseline and after 12 months. Pituitary volume significantly increased in the schizophrenic subjects after treatment (12% increase). This appeared to be specific to the prolactin-elevating drugs. In controls, pituitary volume did not change significantly (3% decrease). Pituitary volume may be a useful biomarker for treatments that affect neuroendocrine function.

Development and sexual dimorphism of the pituitary gland.

The pituitary gland plays a central role in sexual development and brain function. Therefore, we examined the effect of age and gender on pituitary volume in a large sample of healthy children and adults. Volumetric magnetic resonance imaging (MRI) was conducted in one hundred and fifty four (77 males and 77 females) healthy participants. Males were between the ages of 7 to 35 years (16.91+/-5.89 years) and females were 7 to 35 years of age (16.75+/-5.75 years). Subjects were divided into subgroups of age (7 to 9, 10 to 13, 14 to 17, 18 to 21, 22 and older) and sex (male/female). Pituitary gland volume differed between sexes when comparing the age groups (F=3.55, df=2, 143, p=0.03). Females demonstrated larger pituitary glands than males in the age 14 to 17 year old groups (p=0.04). Young (19 years and under) and old (20 years and older) females demonstrated a correlation between pituitary volume and age. Males did not show this relationship. These findings provide additional evidence for gender differences in the normative anatomy of the pituitary and may have relevance for the study of various childhood onset neuropsychiatric disorders in which pituitary dysfunction has been implicated.

Pituitary volume in neuroleptic-naïve schizophrenia: a structural MRI study.

Abnormalities in the hypothalamic-pituitary-adrenal axis (HPA) have been implicated in psychosis. To our knowledge, no prior study has measured pituitary volume in a neuroleptic-naïve schizophrenic population. Herein, we present data exploring the volumetric differences in a sample of antipsychotic-naïve patients with a DSM-IV diagnosis of schizophrenia versus appropriately matched healthy controls. Pituitary volumes were measured in 51 patients with schizophrenia (36 males, 15 females, mean age+/-S.D.: 25.2+/-7.4 years) and 55 healthy controls (30 males, 25 females; mean age+/-S.D.: 25.2+/-6.6 years) Measurements were conducted on 1.5 mm thick T1-weighted coronal images from a 1.5T scanner by two trained raters. Patients with schizophrenia had significantly smaller pituitary volumes than healthy control subjects (mean volume+/-S.D.=0.58+/-0.14 cm(3) and 0.66+/-0.17 cm(3) respectively; ANCOVA (using intracranial volume, gender and age as covariates), F=6.81, df=1, 101; p=0.01). These findings provide new evidence of a smaller pituitary volume in neuroleptic-naïve patients with schizophrenia. The observed alterations in pituitary volume are consistent with neuroendocrine studies that have reported abnormalities in the HPA axis in psychosis. Similar volume reductions have been seen in other neuropsychiatric populations and may cut across diagnostic boundaries.