title: Neuroimmunological parameters in panic disorder.
abstract: BACKGROUND
  The interaction between immune cells, neurotransmitters and the neuroendocrinological systems plays a role in affective disorders, especially depression. Although panic disorder (PD) shares a lot of features with depression, it is clearly a distinct disorder. Reports on immunological parameters in PD don't provide a clear picture of the immunological status of PD patients. This can partly be attributed to methodological differences between studies and small patient groups.
  
  
  OBJECTIVE
  The present study aims to assemble all studies on immunological parameters in PD in order to combine all available data to gain a broader perspective on this matter.
  
  
  METHODS
  PubMed was searched for studies describing immunological parameters in PD patients without comorbid disorders or medication use. All studies had to include a healthy control group and the outcome measures had to be shared by at least one other study.
  
  
  RESULTS
  Fourteen articles were found. Although the T-lymphocytic branch and the innate immune system were normal, the B-lymphocytic branch showed some differences between PD patients and healthy controls. B-cell counts were increased in PD patients, which was underlined by increased human leucocyte antigen (HLA)-DR counts and increased immunoglobulin A levels. However, B-cell activity following mitogen stimulation was normal.
  
  
  CONCLUSIONS
  PD patients show increased B-cell numbers. The finding that B-cell activity is not increased can possibly be attributed to functional exhaustion of these cells. The meaning of this finding remains unclear, although it may be potentially important in affective disorders as the same has been found in depression.
authors.affiliation: 1Department of Psychiatry and Neuropsychology and Vijverdal Academic Anxiety Center, Maastricht University, Maastricht, the Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: van Duinen
authors.affiliation: 1Department of Psychiatry and Neuropsychology and Vijverdal Academic Anxiety Center, Maastricht University, Maastricht, the Netherlands.
authors.forename: K R J
authors.initials: KR
authors.lastname: Schruers
authors.affiliation: 1Department of Psychiatry and Neuropsychology and Vijverdal Academic Anxiety Center, Maastricht University, Maastricht, the Netherlands.
authors.forename: E J L
authors.initials: EJ
authors.lastname: Griez
authors.affiliation: 1Department of Psychiatry and Neuropsychology and Vijverdal Academic Anxiety Center, Maastricht University, Maastricht, the Netherlands.
authors.forename: M
authors.initials: M
authors.lastname: Maes