α1-acid glycoprotein and α1-antitrypsin as early markers of treatment response in patients receiving the intensive phase of tuberculosis therapy

The identification of early markers that predict the response to anti-tuberculosis treatment would facilitate evaluation of new drugs and improve patient management. This study aimed to determine whether selected acute phase proteins and micronutrients measured at the time of diagnosis and during the first weeks of treatment could predict treatment responses during the 2-month standard intensive phase of therapy. For this purpose, α1-antitrypsin, α1-acid glycoprotein, α2-macroglobulin, C-reactive protein, C3, C4, zinc, copper and selenium concentrations were measured in Brazilian patients with smear-positive tuberculosis at the time of diagnosis and 1, 3, 5 and 8 weeks after initiation of therapy. Patients were classified into fast (n = 29), intermediate (n = 18) and slow responders (n = 10) if they were smear-negative at 3, 5 or 8 weeks of treatment. α1-acid glycoprotein on enrolment and 1 week of treatment, α1-antitrypsin at week 1 and C-reactive protein and C3 after 3 weeks of therapy were higher in slow responders than in fast responders. α1-antitrypsin and α1-acid glycoprotein may be helpful in predicting treatment response at the time of initiation of therapy, and could be used as early markers to identify patients with an increased likelihood of treatment failure.