Coping with TB immune reconstitution inflammatory syndrome.

The TB immune reconstitution inflammatory syndrome (IRIS) is a relatively frequent complication in HIV-TB-coinfected patients after they start highly active antiretroviral therapy (HAART). There are two forms of TB IRIS: the 'paradoxical' type (clinical worsening of a patient on TB treatment) and the 'unmasking' type (undiagnosed TB becoming apparent after starting HAART). Their pathogeneses are not fully understood, although, as the name suggests, IRIS following initiation of HAART is accompanied by an increase in immune responses to Mycobacterium tuberculosis. The diagnosis of TB IRIS is mainly clinical; so far there are no laboratory tests able to diagnose or predict TB IRIS. Risk factors for TB IRIS include a low CD4(+) lymphocyte count, disseminated TB infection at HAART initiation and a short interval between TB treatment and HAART initiation. TB IRIS complicates the treatment and care for HIV-TB-coinfected patients. In this paper, we discuss some aspects of pathogenesis and options for the treatment and prevention of TB IRIS.

Identification fo Mycobacterium leprae antigens in tissues of leprosy patients using monoclonal antibodies

Five monoclonal antibodies (MAbs) directed against antigens of Mycobacterium leprae were tested for their ability to bind to components of tissue sections prepared from biopsies taken from patients with various forms of leprosy. Immunoperoxidase was the most successful marker system used, although immunofluorescence and alkaline phosphatase were also successful in certain cases. Positivity was high with all five antibodies successfully staining those sections containing a bacterial index of 3+ or more; sections with 0 bacterial counts also had areas staining positively with two of the MAbs. The positive staining in the tissues was confined to areas infiltrated by inflammatory cells; however it was not identifiable as being associated with individual bacteria. These findings suggest that immunostaining with specific monoclonal antibodies can help to identify leprosy in diagnostic samples in which acid-fast bacilli are not identifiable by standard histochemical means. Immunohistochemical techniques are likely to be valuable in studies of the distribution of M. leprae antigens and their association with individual tissue elements