“Tuberculosis among HIV-positive Patients: An International Prospective Observational Cohort Study” is a multicenter study conducted throughout Europe, Eastern Europe and Latin America. The well-established collaboration includes 64 clinics in 19 countries, of which 18 clinics are located in the Eastern part of Europe.

Tuberculosis (TB) is the most frequent co-infection among HIV-positive patients worldwide and the most frequent cause of death. The convergence of the TB and HIV epidemics has substantially increased the incidence, difficulty in diagnosis and associated mortality of TB, and in turn, TB accelerates the progression of the HIV disease. Rapidly increasing rates of anti-TB drug resistance has been observed in recent years, particularly in the Eastern European region that holds the world’s highest number of multidrug resistant TB (MDR-TB) and extensively resistant TB (XDR-TB). The emergence of resistant cases of TB, including MDR-TB and XDR-TB, has greatly diminished the success rate of standard anti-TB therapy, which has particular implications for HIV-positive patients. Furthermore, there may be major regional diversities across Europe and Latin America in these clinical issues related to TB.

There are still several unresolved issues related to the optimal management of TB in the HIV-positive patient. These include the clinical approach to interactions between TB and HIV therapies, the overlapping toxicities between these treatments, and the role of prophylaxis against TB. The best time to initiate cART and TB therapy in relation to each other, particularly in patients with advanced HIV infection, remains a clinical dilemma because of the concern regarding potential immune reconstitution inflammatory syndrome (IRIS). Further, the best way to manage cases with resistant TB and relevant factors for the clinical outcome remains to be elucidated.