title: The longitudinal profile of bilirubin and ferritin in the cerebrospinal fluid following a subarachnoid hemorrhage: diagnostic implications.
abstract: BACKGROUND
  Cerebrospinal fluid (CSF) spectrophotometry for bilirubin is a highly sensitive test in the diagnostic work up of a suspected subarachnoid hemorrhage (SAH).
  
  
  METHODS
  We report two cases suffering from an aneurysmal SAH in which extraventricular drainage for acute hydrocephalus was required. Longitudinal analyses of the CSF samples demonstrated that CSF bilirubin was detectable in all cases during the first week, becoming undetectable in one case in the second week. Importantly, CSF ferritin levels rose substantially (>1,000 ng/ml) after 6 days, peaking around 3,000 ng/ml after 2 weeks (normal upper reference range 12 ng/ml). In both cases blood was visible on the initial CT brain scan, disappearing on a later scan.
  
  
  CONCLUSIONS
  CSF ferritin levels may be an important additional laboratory test in the diagnostic work-up of patients with a suspected SAH. CSF ferritin levels may prove particularly helpful in cases with late presentation if the CT brain scan is normal and CSF bilirubin level is undetectable.
authors: Department of Neuroimmunology, UCL Institute of Neurology and The Tavistock Intensive Care Unit, The National Hospital for Neurology and Neurosurgery, Queen Square, London, WC1N 3BG, UK. a.petzold@ion.ucl.ac.uk
authors: A
authors: A
authors: Petzold
authors: V
authors: V
authors: Worthington
authors: C
authors: C
authors: Pritchard
authors: I
authors: I
authors: Appleby
authors: N
authors: N
authors: Kitchen
authors: M
authors: M
authors: Smith
mesh_terms: D001663:Bilirubin / Q000134:cerebrospinal fluid*; D015415:Biomarkers / Q000134:cerebrospinal fluid*; D005260:Female; D005293:Ferritins / Q000134:cerebrospinal fluid*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D013345:Subarachnoid Hemorrhage / Q000134:cerebrospinal fluid* / Q000175:diagnosis* / Q000000981:diagnostic imaging; D013346:Subarachnoid Space / Q000378:metabolism; D014057:Tomography, X-Ray Computed
chemical_list: D015415:Biomarkers; D005293:Ferritins; D001663:Bilirubin