Our study aimed to select, among anti HIV positive PPD positive patients, those with a greater risk of developing active tuberculosis, in order to better target isoniazide chemoprophylaxis. Thus, we recruited 115 anti HIV positive (mean age 24 years) and 50 anti HIV negative (mean age 23 years). All patients were tested for: PPD skin test, CD4+ and CD8+ lymphocytes count, serum β2-microglobulin and HIV-p24 antigen detection. All subjects were followed up between 1991 and 1993 for active tuberculosis occurrence. Ten controls (20%) were PPD positive; mean β2-microglobulin among controls was 3.2 mg/l, mean CD4+ and CD8+ were 1137 and 814/mm 3 respectively. Eleven (9%) anti HIV positive were p24 positive, serum β2-microglobulin was 4.2 mg/l, CD4+ and CD8+ were 540 and 1108/mm 3 respectively: 23 anti HIV positive drug users (20%) were PPD positive. During the 2-year follow-up, none of the anti HIV negative subjects developed active tuberculosis versus 6 (5%) out of those anti HIV positive (all PPD positive). Mean β2-microglobulin and CD4+ cells, as well as the number of p24 positive patients, did not significantly differ between anti HIV positive-PPD positive with and without tuberculosis reactivation. On the contrary, the diameter of PPD-elicited cutaneous induration was bigger in those patients who reactivated tuberculosis. In addition the CD8+ number was significantly lower among anti HIV positive patients who showed clinical tuberculosis during the follow-up. Our investigation indicates a similar prevalence of PPD reactivity between anti HIV positive and anti HIV negative subjects: thus indicating that anti HIV seropositivity without an evident cellular immunodepression, does not interfere with tuberculin reactivity. Anti HIV positive patients should be tested for PPD reactivity promptly, in order to evidentiate those patients with a greater risk for tuberculosis reactivation; anti HIV and PPD positive patients should be treated with isoniazide as prophylaxis; our data suggest to target isoniazide prophylaxis to those anti HIV positive subjects with more than 5 cutaneous induration and a lower number of CD8+ lymphocytes.
|Titolo:||Factors predicting tuberculosis reactivation in HIV-infected patients|
|Data di pubblicazione:||1995|
|Appare nelle tipologie:||1.1 Articolo in rivista|