title: Rational application of adenosine deaminase activity in cerebrospinal fluid for the diagnosis of tuberculous meningitis.
abstract: OBJECTIVE
  Tuberculous meningitis (TBM) is one of the most serious and difficult to diagnose manifestations of TB. An ADA value >9.5 IU/L has great sensitivity and specificity. However, all available studies have been conducted in areas of high endemicity, so we sought to determine the accuracy of ADA in a low endemicity area.
  
  
  METHODS
  This retrospective study included 190 patients (105 men) who had ADA tested in CSF for some reason. Patients were classified as probable/certain TBM or non-TBM based on clinical and Thwaite's criteria. Optimal ADA cutoff was established by ROC curves and a predictive algorithm based on ADA and other CSF biochemical parameters was generated.
  
  
  RESULTS
  Eleven patients were classified as probable/certain TBM. In a low endemicity area, the best ADA cutoff was 11.5 IU/L with 91 % sensitivity and 77.7 % specificity. We also developed a predictive algorithm based on the combination of ADA (>11.5 IU/L), glucose (<65 mg/dL) and leukocytes (≥13.5 cell/mm(3)) with increased accuracy (Se: 91 % Sp: 88 %).
  
  
  CONCLUSIONS
  Optimal ADA cutoff value in areas of low TB endemicity is higher than previously reported. Our algorithm is more accurate than ADA activity alone with better sensitivity and specificity than previously reported algorithms.
authors: Servicio de Enfermedades Infecciosas, Hospital Universitario San Cecilio, Avda Dr. Olóriz 16, 18012, Granada, Spain. jordi@ugr.es.|Laboratorio de Investigación Anti Microbiana, Hospital Universitario San Cecilio, Granada, Spain. jordi@ugr.es.
authors: Jorge
authors: J
authors: Parra-Ruiz
authors: Servicio de Enfermedades Infecciosas, Hospital Universitario San Cecilio, Avda Dr. Olóriz 16, 18012, Granada, Spain.
authors: V
authors: V
authors: Ramos
authors: Servicio de Medicina Interna, Complejo Asistencial Universitario de Burgos, Burgos, Spain.
authors: C
authors: C
authors: Dueñas
authors: Laboratorio de Investigación Anti Microbiana, Hospital Universitario San Cecilio, Granada, Spain.|Unidad de Gestión Clínica de Laboratorio, Hospital Universitario San Cecilio, Granada, Spain.
authors: N M
authors: NM
authors: Coronado-Álvarez
authors: Servicio de Medicina Interna, Complejo Asistencial Universitario de Burgos, Burgos, Spain.
authors: R
authors: R
authors: Cabo-Magadán
authors: Servicio de Medicina Interna, Complejo Asistencial Universitario de Burgos, Burgos, Spain.
authors: V
authors: V
authors: Portillo-Tuñón
authors: Servicio de Enfermedades Infecciosas, Hospital Universitario San Cecilio, Avda Dr. Olóriz 16, 18012, Granada, Spain.
authors: D
authors: D
authors: Vinuesa
authors: Servicio de Enfermedades Infecciosas, Hospital Universitario San Cecilio, Avda Dr. Olóriz 16, 18012, Granada, Spain.
authors: L
authors: L
authors: Muñoz-Medina
authors: Servicio de Enfermedades Infecciosas, Hospital Universitario San Cecilio, Avda Dr. Olóriz 16, 18012, Granada, Spain.|Laboratorio de Investigación Anti Microbiana, Hospital Universitario San Cecilio, Granada, Spain.
authors: J
authors: J
authors: Hernández-Quero
mesh_terms: D000243:Adenosine Deaminase / Q000134:cerebrospinal fluid*; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D002555:Cerebrospinal Fluid / Q000737:chemistry*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014390:Tuberculosis, Meningeal / Q000175:diagnosis*; D055815:Young Adult
chemical_list: D000243:Adenosine Deaminase
keywords: Algorithm; Central system fluid; Meningitis; Tuberculosis