title: Cerebrospinal fluid tau concentrations in HIV infected patients with suspected neurological disease.
abstract: OBJECTIVE
  To measure cerebrospinal fluid (CSF) tau in HIV infected patients with acute neurological episodes and to correlate the findings with the type and severity of neurological disease.
  
  
  METHODS
  CSF tau was prospectively measured in 76 consecutive HIV infected patients admitted to a specialist unit at UCL Hospitals, London, for investigation of acute neurological episodes: the results were compared with the clinical diagnoses.
  
  
  RESULTS
  24 patients had HIV associated dementia complex (HADC), 10 had lymphoma (including four with primary CNS lymphoma), 20 had cerebral infections (including five with CMV encephalitis, five with VZV infection, seven with cryptococcal meningitis, two with toxoplasmosis, and one with progressive multifocal leucoencephalopathy); 22 patients had miscellaneous conditions, including nine with self limiting headache/fever. 62 patients (82%) had normal CSF tau concentration and 14 patients (18%) had elevated tau. In those with HADC, there was no correlation between the degree of dementia or atrophy on magnetic resonance imaging and CSF tau. Elevated CSF tau was associated with poor outcome as six of eight patients who died within 4 weeks of lumbar puncture had elevated tau (p = 0.0024, two tailed Fisher's exact test).
  
  
  CONCLUSIONS
  CSF tau levels are not elevated in the majority of HIV infected patients presenting with acute neurological episodes. CSF tau levels show no correlation with severity of dementia/atrophy on magnetic resonance imaging. Although elevated CSF tau was observed in some patients with conditions causing cerebral necrosis, the finding did not delineate underlying pathology but was associated with poor outcome.
authors.affiliation: Department of Neuroimmunology, Institute of Neurology, National Hospital for Neurology and Neurosurgery, Queen Square, London WC1N 3BG, UK.
authors.forename: A J
authors.initials: AJ
authors.lastname: Green
authors.forename: G
authors.initials: G
authors.lastname: Giovannoni
authors.forename: M A
authors.initials: MA
authors.lastname: Hall-Craggs
authors.forename: E J
authors.initials: EJ
authors.lastname: Thompson
authors.forename: R F
authors.initials: RF
authors.lastname: Miller
mesh_terms: D015526:AIDS Dementia Complex / Q000134:cerebrospinal fluid; D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000134:cerebrospinal fluid; D018791:CD4 Lymphocyte Count; D005260:Female; D015658:HIV Infections / Q000134:cerebrospinal fluid* / Q000150:complications; D015497:HIV-1; D006801:Humans; D016483:Lymphoma, AIDS-Related / Q000134:cerebrospinal fluid* / Q000175:diagnosis; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009422:Nervous System Diseases / Q000134:cerebrospinal fluid* / Q000175:diagnosis / Q000821:virology; D011379:Prognosis; D011446:Prospective Studies; D012720:Severity of Illness Index; D016875:tau Proteins / Q000134:cerebrospinal fluid*
chemical_list: D015415:Biomarkers; D016875:tau Proteins