title: Serum soluble interleukin-2 receptor: a useful indicator of the clinical course in pulmonary tuberculosis.
abstract: METHODS
  In tuberculosis both host protection and most pathogenic mechanisms depend on T lymphocytes. After activation by mycobacterial antigens, T cells both secrete interleukin-2 (IL-2) and express a high affinity receptor for this molecule (IL-2R) on their own surface. A soluble fraction of IL-2 receptor (sIL-2R), released from cell membrane, is detectable in serum and its concentration is known to be elevated in tuberculosis.
  
  
  OBJECTIVE
  To ascertain the role of sIL-2R as an indicator of clinical evolution and response to antituberculosis treatment.
  
  
  METHODS
  A prospective study, in which we have measured serum sIL-2R in 52 patients (42 with active and 10 with inactive pulmonary tuberculosis) and in 36 healthy controls. In 20 patients, serum sIL-2R levels were measured serially throughout the treatment. Levels of sIL-2R were correlated to clinical and radiological parameters.
  
  
  RESULTS
  Serum sIL-2R was significantly increased in patients with tuberculosis as compared to healthy subjects. Both the radiological findings and the clinical state of patients showed a good correlation with sIL-2R. All patients with normal values of sIL-2R 6 months after starting therapy had a favourable clinical evolution.
  
  
  CONCLUSIONS
  Serum sIL-2R is a useful marker of the clinical state and evolution of patients with pulmonary tuberculosis. The detection of permanently high values beyond 3-6 months of treatment suggests that additional drugs or prolonged administration would be advisable in order to ensure full recovery.
authors.affiliation: Sección de Medicina Interna, Hospital Los Arcos, Santiago de la Ribera, Spain.
authors.forename: M J
authors.initials: MJ
authors.lastname: Avilés Inglés
authors.forename: C
authors.initials: C
authors.lastname: Contessotto
authors.forename: J
authors.initials: J
authors.lastname: Ontañón Rodriguez
authors.forename: A
authors.initials: A
authors.lastname: García Alonso
authors.forename: M
authors.initials: M
authors.lastname: Muro Amador
authors.forename: M
authors.initials: M
authors.lastname: Canteras Jordana
authors.forename: F
authors.initials: F
authors.lastname: Sánchez Gascón
authors.forename: R
authors.initials: R
authors.lastname: Alvarez López
mesh_terms: D000328:Adult; D000995:Antitubercular Agents / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011859:Radiography; D015375:Receptors, Interleukin-2 / Q000378:metabolism*; D014374:Tuberculin Test; D014397:Tuberculosis, Pulmonary / Q000097:blood* / Q000175:diagnosis / Q000000981:diagnostic imaging
chemical_list: D000995:Antitubercular Agents; D015375:Receptors, Interleukin-2