title: Evidence of cerebrospinal fluid abnormalities in patients with depressive syndromes.
abstract: Depression is the most prevalent psychiatric disease. In addition to primary, idiopathic depression, there are multiple secondary organic forms. However, distinguishing the two can be difficult, information about cerebrospinal fluid (CSF) basic findings in patients with depressive syndromes is sparse. Therefore, we investigated CSF alterations in so far the largest sample of patients with depressive syndromes. We hypothesized that increased prevalence of CSF pleocytosis, blood-brain-barrier (BBB) dysfunction, and oligoclonal bands (OCBs) would be observed as possible markers of underlying immunological processes.
  
  
  
  From January 2006 until October 2013, we performed CSF basic diagnostics in 125 patients with depressive syndromes. We also performed serum and CSF autoantibody measurements, cerebral magnetic resonance imaging (cMRI) and electroencephalography (EEG).
  
  
  
  Four % of the patients displayed increased CSF white blood cell counts (WBC), 46.4% had increased protein concentrations, and 19.4% had pathological albumin quotients. OCBs in the CSF were detected in 6.5%. Overall, CSF basic diagnostics were abnormal in 56%. Including instrument-based diagnostics, we found alterations in 80.8% of patients. Suicidal tendencies correlated with an increased WBC count (r=0.276, p=0.002).
  
  
  
  In this open, uncontrolled study, we investigated mainly CSF samples of depressive patients with signs of organic features. Therefore, the study cohort is not representative of idiopathic depression.
  
  
  
  The main findings of this study are the high rates of pathological (although mainly unspecific) CSF findings. We discuss the findings regarding possible immunological mechanisms and the vascular depression hypothesis. If these findings are associated with low-level inflammation of the central nervous system, new treatment alternatives could be considered. More and better controlled research is necessary.
authors.affiliation: Section for Experimental Neuropsychiatry, Department for Psychiatry & Psychotherapy, Medical Center - University of Freiburg, Hauptstr. 5, 79104 Freiburg, Germany. Electronic address: dominique.endres@uniklinik-freiburg.de.
authors.forename: Dominique
authors.initials: D
authors.lastname: Endres
authors.affiliation: Section for Experimental Neuropsychiatry, Department for Psychiatry & Psychotherapy, Medical Center - University of Freiburg, Hauptstr. 5, 79104 Freiburg, Germany.
authors.forename: Evgeniy
authors.initials: E
authors.lastname: Perlov
authors.affiliation: Department for Neurology, Medical Center - University of Freiburg, Breisacher Str. 64, 79106 Freiburg, Germany.
authors.forename: Rick
authors.initials: R
authors.lastname: Dersch
authors.affiliation: Department for Neurology, Medical Center - University of Freiburg, Breisacher Str. 64, 79106 Freiburg, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Baumgartner
authors.affiliation: Department for Neurology, Medical Center - University of Freiburg, Breisacher Str. 64, 79106 Freiburg, Germany.
authors.forename: Tilman
authors.initials: T
authors.lastname: Hottenrott
authors.affiliation: Department for Neurology, Medical Center - University of Freiburg, Breisacher Str. 64, 79106 Freiburg, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Berger
authors.affiliation: Department for Neurology, Medical Center - University of Freiburg, Breisacher Str. 64, 79106 Freiburg, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Stich
authors.affiliation: Section for Experimental Neuropsychiatry, Department for Psychiatry & Psychotherapy, Medical Center - University of Freiburg, Hauptstr. 5, 79104 Freiburg, Germany.
authors.forename: Ludger
authors.initials: L
authors.lastname: Tebartz van Elst
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000418:Albumins / Q000134:cerebrospinal fluid; D001323:Autoantibodies / Q000134:cerebrospinal fluid; D015415:Biomarkers / Q000134:cerebrospinal fluid; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology; D003866:Depressive Disorder / Q000134:cerebrospinal fluid*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D007958:Leukocyte Count / Q000706:statistics & numerical data; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D055815:Young Adult
chemical_list: D000418:Albumins; D001323:Autoantibodies; D015415:Biomarkers
keywords: Blood-brain-barrier-dysfunction; Cerebrospinal fluid; Depressive syndrome; Immunological encephalopathy