title: The validity of cerebrospinal fluid parameters for the diagnosis of tuberculous meningitis.
abstract: OBJECTIVE
  To assess the diagnostic validity of laboratory cerebrospinal fluid (CSF) parameters for discriminating between tuberculous meningitis (TBM) and other causes of meningeal syndrome in high tuberculosis incidence settings.
  
  
  METHODS
  From November 2009 to November 2011, we included patients with a clinical suspicion of meningitis attending two hospitals in Lima, Peru. Using a composite reference standard, we classified them as definite TBM, probable TBM, and non-TBM cases. We assessed the validity of four CSF parameters, in isolation and in different combinations, for diagnosing TBM: adenosine deaminase activity (ADA), protein level, glucose level, and lymphocytic pleocytosis.
  
  
  RESULTS
  One hundred and fifty-seven patients were included; 59 had a final diagnosis of TBM (18 confirmed and 41 probable). ADA was the best performing parameter. It attained a specificity of 95%, a positive likelihood ratio of 10.7, and an area under the receiver operating characteristics curve of 82.1%, but had a low sensitivity (55%). None of the combinations of CSF parameters achieved a fair performance for 'ruling out' TBM.
  
  
  CONCLUSIONS
  Finding CSF ADA greater than 6 U/l in patients with a meningeal syndrome strongly supports a diagnosis of TBM and permits the commencement of anti-tuberculous treatment.
authors: Unit of General Epidemiology and Disease Control, Institute of Tropical Medicine of Antwerp, Nationalestraat 155, B-2000 Antwerp, Belgium; Unidad de Análisis y Generación de Evidencias en Salud Publica (UNAGESP), Instituto Nacional de Salud del Peru, Lima, Peru. Electronic address: lelysol@hotmail.com.
authors: Lely
authors: L
authors: Solari
authors: Alonso
authors: A
authors: Soto
authors: Juan Carlos
authors: JC
authors: Agapito
authors: Vilma
authors: V
authors: Acurio
authors: Dante
authors: D
authors: Vargas
authors: Tulia
authors: T
authors: Battaglioli
authors: Roberto Alfonso
authors: RA
authors: Accinelli
authors: Eduardo
authors: E
authors: Gotuzzo
authors: Patrick
authors: P
authors: van der Stuyft
mesh_terms: D000243:Adenosine Deaminase / Q000134:cerebrospinal fluid; D000328:Adult; D019540:Area Under Curve; D005260:Female; D005947:Glucose / Q000134:cerebrospinal fluid; D006801:Humans; D008297:Male; D008875:Middle Aged; D010568:Peru; D012372:ROC Curve; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014390:Tuberculosis, Meningeal / Q000134:cerebrospinal fluid* / Q000175:diagnosis*
chemical_list: D000243:Adenosine Deaminase; D005947:Glucose
keywords: Adenosine deaminase; Diagnosis; Neurological; Sensitivity and specificity; Tuberculous meningitis