1 Apart from severe immune compromise, such as seen with HIV infection, immune immaturity related to young age (mainly children infected before <2?years of age) is associated with a greatly increased risk to develop active disease following infection with Mycobacterium tuberculosis. Infants (i.e. children <12?months of age) experience the highest risk; 50% develop TB after infection in the absence of <a href="http://www.selleckchem.com/products/XAV-939.html
">XAV-939 nmr preventive measures and up to 30% develop progressive pulmonary or disseminated (miliary) TB.2 HIV infection increases this risk even further; a recent study in the Western Cape province, an area with a high TB incidence of 1037/100?000 population in 2006, demonstrated a relative risk of 24 (95% CI: 17�C34) for culture-confirmed TB in HIV-infected infants compared with HIV-uninfected infants.3 Reasons postulated for this increase were immunosuppression, more exposure to adult TB source cases because of increased susceptibility to TB in adults caring for these infants and the likelihood that Bacille Calmette-Gu��rin (BCG) vaccination is less effective in HIV-infected children.3 It is possible that not only HIV-infected but also HIV-exposed uninfected infants are at higher risk of TB, because of increased exposure to TB from immunodeficient household members and potential immunosuppression in these infants.4,5 On the other end of the spectrum, life expectancy continues to increase in the developed world; therefore, TB in the elderly is likely to be a continuing, if not an increasing problem. In tuclazepam
many developing countries, especially in Africa, life expectancy is decreasing mainly because of HIV infection in young adults, leading to a likely decline in number of elderly people, but with the general population having increased exposure to TB, it is likely that worldwide TB in the elderly may become an increasing problem. Although HIV infection is relatively uncommon in the elderly and therefore not a major risk factor in this age group, immunity in the elderly is often waning, and because of high infection rates with M. tuberculosis at young age even in currently developed countries, the elderly remain at high risk for TB disease mainly due to reactivation. In both extremes of age, the symptoms at presentation are often uncharacteristic at best, and often vague. Alertness click here
and awareness of TB as a possible diagnosis in these age groups is paramount. Adverse events to anti-TB treatment are more common in the elderly and more difficult to identify in the very young; therefore, more careful monitoring is needed. Identifying patients at risk in both age groups is challenging, because mothers or other household members are often not yet diagnosed with TB or unaware of the risk to the infant if an adult has TB, while contact tracing of patients living in residential or nursing homes can be very problematic and resource intense.