Tuberculosis a re-emerging disease.

Two billion people, nearly one-third of the population worldwide, are infected by M. tuberculosis. Since 2008, the number of foreign TB cases in Italy has overtaken native cases. Even though TB prevalently affects elderly Italian natives, the diagnosis of the disease in these subjects is difficult and frequently delayed because of the low index of suspicion due to loss of clinical experience. Moreover, the large use of TNF inhibitors has created a new risk group for the disease, highlighting the need for tougher screening practices to reduce new cases of severe TB. Immigration from high-incidence countries like Romania has increased the number of cases of multi-drug resistant TB. These cases are usually difficult to treat because of fewer treatment options and also difficulty in managing patients with adverse socioeconomic conditions such as homelessness. It is mandatory that young doctors acquire experience in the diagnosis and treatment of TB, a disease that is not so infrequent as it was a decade or two ago.