[Determination of antibodies against A-60 antigen for diagnosis of M. tuberculosis infection. A useful tool for rationalization of chemoprophylaxis in HIV patients].
OBJECTIVE
To identify M. tuberculosis infection in HIV patients by use of PPD and an ELISA test detecting the presence of antibodies against antigen A-60 of M. bovis.


METHODS
116 incoming HIV patients were classified according to the CDC. The status of M. tuberculosis infection was probed with PPD (RT-23) and the state of anergy was estimated by a Multitest CM1 (Multitext). The presence of circulating antibodies of the IgG class against antigen A-60 was analysed by an ELISA. The clinical course of the patients was followed for 24 month.


RESULTS
A positive serology (A-60) was found in 52.58% of the patients, coinciding with 70.45% of the positive PPD (p < 0.003). This statical observation was found when we studied all of the individuals, and those with more than 500 CD4 lymphocytes. The Multitext was positive in 11.11% of the patients with PPD (-), all of them without antibodies against A-60. However, 42.2% of the patients who were PPD and Multitext (-), had circulating antibodies against A-60. The following up of the patients during 24 months allowed the detection of 7 news cases of pulmonary tuberculosis, 4 of them had a positive A-60 serology, and 4 were anergy.


CONCLUSIONS
HIV patients with M. tuberculosis infection have circulating antibodies against A-60 antigen of M. bovis with independence of their immunity status. In anergic patients the presence of this antibodies can be an useful tool for rationalizing the prophylaxis against M. tuberculosis. A seropositivity (A-60) indicates as well as does PPD a previous contact with M. tuberculosis.
Blanco
J R
JR
Servicio de Medicina Interna y Enfermedades Infecciosas, Hospital de La Rioja, Avda. de Viana, 1-26001 Logroño, La Rioja.
Martínez de Artola
V
V
Ibarra
V
V
Rosel
L
L
Gómez-Cadiñanos
R
R
Oteo
J A
JA
D017088:AIDS-Related Opportunistic Infections / Q000175:diagnosis / Q000517:prevention & control*; D000328:Adult; D000368:Aged; D000907:Antibodies, Bacterial / Q000276:immunology*; D000942:Antigens, Bacterial / Q000276:immunology*; D000995:Antitubercular Agents / Q000627:therapeutic use; D017635:Clonal Anergy; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009163:Mycobacterium bovis / Q000276:immunology; D009169:Mycobacterium tuberculosis / Q000276:immunology; D014374:Tuberculin Test; D014376:Tuberculosis / Q000175:diagnosis / Q000517:prevention & control*
D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D000995:Antitubercular Agents; C055539:mycobacterial A60 antigen