Tuberculosis
Unlike opportunistic infections in AIDS tuberculosis is also infectious for healthy individuals. Tuberculosis is a potent stimulator of cell-mediated immunity and so may speed up the natural history of HIV disease.
The incidence of tuberculosis is currently increasing in the USA; this is directly attributable to the effects of HIV in certain populations. No increase has occurred yet in Britain but the unpredictable features of the HIV epidemic in heterosexuals, migrants and injecting drug users means careful vigilance is required. Tuberculosis can precede the development of AIDS, be diagnosed at the same time or occur at any time during established AIDS. Tuberculosis in HIV positive patients is AIDS defining and in the USA, the UK and most other European countries is a statutorily notifiable disease.Over two thirds of cases of tuberculosis in HIV-infected patients present with pulmonary disease. Clinical presentation varies according to the stage of HIV disease. Early on, with relatively well preserved cell-mediated immunity, pulmonary tuberculosis resembles classic adult post-primary disease with upper lobe infiltrates and cavitation; the tuberculin test is usually positive and acid and alcohol fast bacteria (AAFB) are frequently seen when sputum is examined by microscopy. With advanced HIV disease and destroyed cell immunity, presentation is non-specific with fever, weight loss and fatigue, with or without cough. Patients with low CD4 counts a day. Aspergillus pulmonary infection has a very poor prognosis despite treatment with amphotericin. It occurs almost exclusively in patients with advanced HIV disease who are either neutropenic or who have received broad-spectrum antibiotics.