Immunosuppressive therapy for chronic uveitis: optimising therapy with steroids and cyclosporin A

Abstract

Fifty per cent of cases of uveitis are classified as idiopathic12 while many of the others are associated with or form part of other disease entities. However, before considering and commencing immunosuppressive therapy for uveitis, direct infectious causes must be excluded so that appropriate therapy can be commenced. Therefore, management of endogenous posterior uveitis depends on both clinical and associated laboratory based investigations to exclude any infectious aetiology. Many cases of infectious uveitis are clinically obvious—for example, opportunistic infections in immunocompromised individuals (especially in association with HIV) are increasingly frequent causes of uveitis, the treatment of which is highly dependent on specific antimicrobial therapy. In non-immunocompromised individuals, toxoplasmosis (depending on which country and region) is one of the leading causes of uveitis,28 and although immunosuppression is used to treat this condition it must be used in conjunction with appropriate antibiotic therapy to reduce the incidence of disease relapse. In certain cases, however, differentiation between infectious and non-infectious endogenous posterior uveitis (EPU) may be more difficult. For example, Lyme disease, miliary tuberculosis, or progressive outer retinal necrosis (PORN), may present with signs identical to those of EPU and, despite adequate clinical assessment, immunosuppressive therapy may have already been started on the basis that the condition was considered non-infectious. In these cases, as well as possible ‘masquerade’ conditions such as ocular lymphoma a failure to respond should be a warning sign that the diagnosis may be incorrect and needs to be reviewed. Patients with true EPU are assumed to be autoimmune in nature,19 and the aim of this review is to focus on the treatment of these primary immune mediated conditions.