Serum soluble interleukin-2 receptor: a useful indicator of the clinical course in pulmonary tuberculosis.
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.
Avilés Inglés
M J
MJ
Sección de Medicina Interna, Hospital Los Arcos, Santiago de la Ribera, Spain.
Contessotto
C
C
Ontañón Rodriguez
J
J
García Alonso
A
A
Muro Amador
M
M
Canteras Jordana
M
M
Sánchez Gascón
F
F
Alvarez López
R
R
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
D000995:Antitubercular Agents; D015375:Receptors, Interleukin-2