Tuberculosis/hiv Co-infection

Tuberculosis (TB) and human immunodeficiency virus/acquired immune deficiency syndrome (HIV/ AIDS) constitute the main burden of infectious disease in resource-limited countries. Estimates by the World Health Orgnisation (WHO) indicate that there are more than nine million new active cases of TB and close to two million deaths per year and 2.6 million new cases of HIV infection and 1.8 million AIDS related deaths occur per year. Myocobacterium tuberculosisHIV co-infection poses particular diagnostic and therapeutic challenges and exert immense pressure on health care systems in African countries with large populations of co-infected individuals. In the individual host the two pathogens, M. tuberculosis and HIV potentiate one another, accelerating the deterioration of immunological functions and resulting in premature death if untreated. TB is the largest single cause of death in the setting of AIDS, accounting for about 26% of AIDSrelated deaths, 99% of which occur in developing countries. Both TB and HIV have profound effects on the immune system, as they are capable of disarming the host's immune responses through mechanism that are not fully understood. HIV co-infection is the most powerful known risk factor of latent TB reactivation 20-fold. Likewise, TB has been reported to exacerbate HIV infection. Various lines of evidence indicate that inborn errors of immunity, as well as genetic polymorphisms, have an impact on susceptibility to TB and HIV.