Choroidal lesions in patients with AIDS

Posterior segment manifestations of HIV/AIDS

The ocular posterior segment manifestations of AIDS may be divided into four categories: retinal vasculopathy, unusual malignancies, neuro-ophthalmologic abnormalities, and opportunistic infections. Microvasculopathy is the most common manifestation. Opportunistic infections, particularly cytomegalovirus retinitis and progressive outer retinal necrosis, are the most likely to result in visual loss due to infection or subsequent retinal detachment. Diagnosis and treatment are guided by the particular conditions and immune status of the patient.

Uveitis in HIV-infected patients

PURPOSE

To determine the prevalence of HIV infection and to find out the possible causes (associated conditions) of uveitis in HIV-infected patients.

METHODS

We retrospectively analyzed the data of 581 patients with uveitis diagnosed over an 11-year period. All patients received a routine eye examination and most of them a general examination as well as complementary tests.

RESULTS

The prevalence of HIV infection was 14.3% (89 patients). Anterior uveitis (62%) was the most frequent form, followed by posterior uveitis (22%), panuveitis (12%) and intermediate uveitis (4%). Associated conditions or causes were found in 88% of these 89 patients, the most frequent being Herpes zoster ophthalmicus (43%), tuberculosis (16%), CMV infection (12%) and toxoplasmosis (10%).

CONCLUSIONS

In HIV-infected patients uveitis is frequently associated with opportunistic infections.

Iritis associated with intravenous cidofovir

OBJECTIVE

To report two patients with AIDS and cytomegalovirus retinitis who developed iritis after receiving intravenous cidofovir. Both experienced recurrent symptoms upon rechallenge.

CASE SUMMARIES

Two HIV-positive patients with cytomegalovirus retinitis infections previously controlled with intravenous ganciclovir or foscarnet were treated with intravenous cidofovir. Symptoms of iritis developed after the second or third dose of cidofovir. One patient experienced symptoms unilaterally, while the other patient had bilateral symptoms. In both patients, the iritis resolved with topical ophthalmic therapy, but recurred following subsequent infusions of cidofovir. Therapy with cidofovir was discontinued, and no further recurrences of iritis were noted. One patient had post-inflammatory fixed dilated pupils.

CONCLUSIONS

Iritis can uncommonly occur in patients receiving intravenous cidofovir and oral probenecid. With prompt drug discontinuation and administration of topical corticosteroids and/or mydriatic agents, symptoms are usually reversible.

Extrapulmonary pneumocystosis

Extrapulmonary pneumocystosis is an exceedingly rare complication of Pneumocystis carinii pneumonia (PCP). Prior to the advent of the human immunodeficiency virus type 1 (HIV-1) epidemic, only 16 cases of extrapulmonary pneumocystosis in individuals who were immunocompromised by a variety of underlying diseases had been reported. Since the beginning of the HIV-1 and related PCP epidemic, at least 90 cases of extrapulmonary pneumocystosis have been reported. This review briefly presents a history of the discovery of P. carinii and its recognition as a human pathogen, the controversy regarding its taxonomy, and the epidemiology of this organism. A more detailed analysis of the incidence of extrapulmonary pneumocystosis in HIV-1-infected individuals and its occurrence despite widespread prophylaxis for PCP with either aerosolized pentamidine or systemic dapsone-trimethoprim is presented. The clinical features of published cases of extrapulmonary pneumocystosis in non-HIV-1-infected individuals are summarized and contrasted with those in HIV-1 infected individuals. The diagnosis of extrapulmonary pneumocystosis is discussed, and because clinical microbiologists and pathologists are the key individuals in establishing the diagnosis, the characteristic microscopic morphology of P. carinii as its appears when stained with a variety of stains is presented and reviewed. The review concludes with a brief discussion of treatments for extrapulmonary pneumocystosis.

Rifabutin-associated uveitis

OBJECTIVE

To review rifabutin-associated uveitis and discuss the mechanism and potential role of drug interactions with clarithromycin and fluconazole in contributing to this adverse event.

DATA SOURCES

A MEDLINE search (1991 through September 1994) of English-language literature using the main MeSH headings "rifabutin" and "uveitis" and the subheadings "adverse effects" and "chemically induced." Relevant articles also were selected from references of identified articles. Abstracts from recent medical conferences of infectious diseases, pharmacology, and HIV were screened for additional data.

STUDY SELECTION AND DATA EXTRACTION

All articles and abstracts reporting uveitis potentially related to rifabutin were considered for inclusion. Fifty-four cases were identified. Pertinent information from the case reports, as judged by the authors, was selected and synthesized for discussion.

DATA SYNTHESIS

Rifabutin is being prescribed increasingly for the treatment and prophylaxis of Mycobacterium avium complex (MAC) infection in the HIV-infected population. Uveitis was initially thought to be a rare, dose-limited complication of rifabutin therapy. In an early dose-ranging tolerance study, uveitis was associated with daily doses of 1200 mg or more. Because this toxicity appeared to be dose-related, lower dosages (300-600 mg/d) of rifabutin were selected for study in subsequent clinical trials. More recent reports noting the association of uveitis with these lower dosages of rifabutin have raised concerns about the prevalence of this adverse event. In the 54 identified cases, patients presented with symptoms of unilateral or bilateral uveitis from 2 weeks to more than 7 months following initiation of rifabutin therapy. In all reported cases, patients were receiving concurrent therapy with clarithromycin and/or fluconazole, both of which have inhibitory effects on rifabutin metabolism. In most cases, uveitis resolved within 1-2 months following discontinuation of rifabutin with or without administration of topical corticosteroids.

CONCLUSIONS

Rifabutin is prescribed frequently for the prophylaxis and treatment of MAC infection, especially in patients with HIV. Uveitis is a rare, dose-related toxicity of this therapy. The risk of rifabutin-associated uveitis may be increased in patients receiving concurrent therapy with clarithromycin or fluconazole because of drug interactions. Patients receiving therapy with combinations of any of these agents should be warned about signs and symptoms of uveitis and be monitored closely for the development of rifabutin toxicity. If uveitis develops, rifabutin therapy should be discontinued promptly.

Cryptococcus presenting as cloudy choroiditis in an AIDS patient

Images

Opportunistic intraocular infections in AIDS

In conclusion, this clinicopathologic study has shown that CMV ocular infection is present in about 16% of terminal AIDS patients. The treatment of CMV retinitis reduces the number of CMV-infected nonocular organs and may also lessen the severity and control the spread of concurrent nonocular infection, both of which may prolong survival in AIDS patients. Other opportunistic infections, involving primarily the choroid, were also seen in a number of patients, some of whom had concurrent intraocular infections with CMV and P carinii, M avium-intracellulare, C neoformans. In addition, all of these choroidal infections were components of disseminated infection, underscoring the increasingly important role of the ophthalmologist in the diagnosis and treatment of disseminated opportunistic infections in AIDS.