Marietta P. Karavellas

Lack of Reactivation of Cytomegalovirus (CMV) Retinitis after Stopping CMV Maintenance Therapy in AIDS Patients with Sustained Elevations in CD4 T Cells in Response to Highly Active Antiretroviral Therapy

The suppression of human immunodeficiency virus (HIV) replication and elevation in CD4 cells observed with protease inhibitor combination regimens known as HAART (highly active antiretroviral therapy) may allow AIDS patients to undergo an immune recovery that allows them to suppress the progression of cytomegalovirus (CMV) retinitis. Eleven AIDS patients receiving HAART with healed CMV retinitis in whom CMV-specific maintenance therapy was discontinued were studied. Median CD4 cell counts were 42 before the initiation of HAART and 183 at discontinuation of anti-CMV therapy. While a median 1.1 log10 drop in plasma HIV-1 RNA was obtained between starting HAART and withdrawal of maintenance therapy for CMV, only 3 of 11 patients maintained plasma HIV RNA below the limits of detection. Reactivation of CMV retinitis after withdrawal of anti-CMV therapy did not occur in any of the patients observed for a median of 156 days (range, 92-558).

Incidence of Immune Recovery Vitritis in Cytomegalovirus Retinitis Patients following Institution of Successful Highly Active Antiretroviral Therapy

This study was conducted to determine the likelihood of the development of a new ocular inflammatory syndrome (immune recovery vitritis, IRV), which causes vision loss in AIDS patients with cytomegalovirus (CMV) retinitis, who respond to highly active antiretroviral therapy (HAART). We followed 30 HAART-responders with CD4 cell counts of >/=60 cells/mm3. Patients were diagnosed with IRV if they developed symptomatic vitritis of >/=1+ severity associated with inactive CMV retinitis. Symptomatic IRV developed in 19 (63%) of 30 patients and in 26 (59%) of 44 eyes over a median follow-up from HAART response of 13.5 months. The annual incidence of IRV was 83/100 person-years. Excluding patients with previous cidofovir therapy did not significantly alter the time course of IRV (P=.79). These data suggest that IRV develops in a significant number of HAART-responders with CMV retinitis and is unrelated to previous cidofovir therapy.

Immune recovery vitritis and uveitis in AIDS: clinical predictors, sequelae, and treatment outcomes.

Purpose To determine 1) clinical predictors of an inflammatory syndrome associated with cytomegalovirus (CMV) retinitis (immune recovery vitritis or uveitis [IRV or IRU]); 2) clinical sequelae of IRV; and 3) the effect of corticosteroid treatment on visual acuity. Methods A cohort study from the AIDS Ocular Research Unit of the University of California, San Diego, and a case series from the Cleveland Clinic consisted of patients who had acquired immunodeficiency syndrome and inactive CMV retinitis who responded to highly active antiretroviral therapy (HAART) with CD4 T-lymphocyte levels >60 cells/mm3. The cohort was followed for a median of 13.5 months following increase in CD4 count. The authors studied the occurrence of IRV, defined as symptomatic (vision decrease and/or floaters) vitritis of 1+ or greater severity associated with inactive CMV retinitis. Macular edema or epiretinal membrane formation was determined by clinical examination and fluorescein angiography. Five eyes were treated with sub-Tenon corticosteroid injections. Results In the cohort study, 19 (63%) of 30 HAART responders developed IRV (26 eyes). The clinical spectrum of inflammation included vitritis, papillitis, macular edema, and epiretinal membranes. Eyes with CMV surface area >30% of the retina were at the highest risk (relative risk = 4.5) of developing IRV (P = 0.03). During follow-up, inflammation persisted without treatment for a median of 20 weeks and 14 patients (16 eyes) developed macular changes. Treatment resulted in vision improvement without reactivation of retinitis. Histology and immunohistochemistry of associated epiretinal membranes showed evidence of chronic inflammation with a predominant T-lymphocyte cell population. In the case series, 3 (38%) of 8 HAART responders developed IRV (4 eyes). All four eyes were treated and resulted in visual acuity improvement of one line. Conclusions Symptomatic IRV or IRU develops in a significant number of patients with CMV retinitis following successful HAART. Eyes with CMV surface area >30% of the retina are at the greatest risk. Eyes with IRV respond favorably to antiinflammatory therapy without reactivation of retinitis. Immune recovery vitritis may be the result of an immunologic reaction to latent CMV antigens in the eye in which T-lymphocytes play a role.

Long-term posterior and anterior segment complications of immune recovery uveitis associated with cytomegalovirus retinitis.

PURPOSE To identify and describe long-term posterior and anterior segment complications of immune recovery uveitis in patients with inactive cytomegalovirus retinitis who are undergoing highly active antiretroviral therapy-mediated recovery of immune function. METHODS A prospective cohort study at a university medical center. Twenty-nine eyes of 21 patients with immune recovery uveitis and inactive cytomegalovirus retinitis were followed for 14.5 to 116 weeks (median, 43 weeks) after diagnosis of immune recovery uveitis. RESULTS Nine eyes of nine patients developed visually important complications involving the posterior segment, anterior segment, or a combination of both. Posterior segment complications included severe proliferative vitreoretinopathy in three eyes and spontaneous vitreous hemorrhage from avulsion of a blood vessel secondary to contraction of the inflamed vitreous in one eye. Proliferative vitreoretinopathy recurred in all cases after surgery, severely compromising the visual outcome. Anterior segment complications included posterior subcapsular cataracts with vision decrease in five eyes and persistent anterior chamber inflammation after cataract extraction, resulting in posterior synechiae and large visually important lens deposits in three eyes. CONCLUSION Persistent inflammation in immune recovery uveitis may lead to vision-threatening complications, such as proliferative vitreoretinopathy, posterior subcapsular cataracts, and severe postoperative inflammation. Immune recovery uveitis is a chronic inflammatory syndrome that may result in complications months to years after the onset of inflammation.

Macular translocation with retinotomy and retinal rotation for exudative age-related macular degeneration.

PURPOSE To determine the effectiveness of macular translocation with retinotomy and retinal rotation in exudative age-related macular degeneration. METHODS After written informed consent was obtained, 20 patients underwent macular translocation. We created a 180-degree retinotomy superior, inferior, and temporal to the macula near the equator. The hinged retinal flap was rotated superiorly or inferiorly to place the center of the fovea over an area of healthy retinal pigment epithelium. The retina was flattened under silicone oil and laser photocoagulation was placed. RESULTS The fovea was moved 425 to 1,700 microm (965+/-262 microm) superiorly or inferiorly. Follow-up time was 2 to 12 months (median 8 months). Complications included macular pucker (3 eyes), subfoveal hemorrhage (2 eyes), macular hole (1 eye), and progression of cataract in phakic eyes (3 eyes). Thirteen of 20 eyes showed various degrees of proliferative vitreoretinopathy with epiretinal membrane formation over the inferior peripheral retina with the inferior retinal detachment stabilized by the silicone oil. One eye progressed to phthisis bulbi. Initial visual acuity ranged from 20/80 to 20/800 (median 20/150) and final visual acuity ranged from light perception to 20/200 (median 20/1000). CONCLUSION The fovea can be moved up to 1,700 microm with retinotomy and retinal rotation; however, there is a high rate of complications. Proliferative vitreoretinopathy is the major complication of this technique and is probably related to the extensive retinotomy and subretinal irrigation inherent in the technique. Other techniques such as scleral shortening may have fewer complications.

Highly active antiretroviral therapy-related immune recovery in AIDS patients with cytomegalovirus retinitis.

OBJECTIVE To characterize cytomegalovirus (CMV) retinitis in human immunodeficiency virus (HIV)-infected patients who demonstrate immune recovery while receiving highly active antiretroviral therapy (HAART). DESIGN Consecutive, noncomparative case series. PARTICIPANTS Twenty-two HIV-positive patients, from two institutions, with a history of CMV retinitis, and with elevated CD4 cell counts after HAART. MAIN OUTCOME MEASURES Duration of healed CMV retinitis without anti-CMV therapy, CD4 cell count, and HIV viral load. INTERVENTION Discontinuation of anti-CMV therapy after persistent elevation of CD4 cell count over 50 cell/mm3 (median, 161/mm3; range, 85-408/mm3). RESULTS The median period of healed CMV retinitis without anti-CMV therapy was 72 weeks (range, 33-116 weeks). Nineteen of 22 patients were still healed without anti-CMV therapy at study end. The three patients with CMV retinitis progression simultaneously had HAART, fail with CD4 cell counts of 37, 35, and 47/mm3. CONCLUSIONS HIV-positive patients with CMV retinitis, who demonstrate a sustained HAART-induced elevation of CD4 cell count on two consecutive counts 3 months apart and whose retinitis remains healed on anti-CMV therapy for greater than 4 months, are likely to remain healed if the anti-CMV therapy is withdrawn. It is important to monitor these patients with indirect ophthalmoscopy because HAART failure may occur and allow CMV retinitis reactivation.

Intraocular Viral And Immune Pathogenesis Of Immune Recovery Uveitis In Patients With Healed Cytomegalovirus Retinitis

Purpose: To investigate immune and viral contributions to the pathogenesis of immune recovery uveitis (IRU), which presents as vitritis, macular edema, or formation of epiretinal membranes, and develops in patients with acquired immunodeficiency syndrome (AIDS) who experienced cytomegalovirus (CMV) retinitis before antiretroviral treatment (ART) induced immune reconstitution. Methods: Aqueous and vitreous fluids from patients with IRU, active CMV retinitis, and control human immunodeficiency virus (HIV)-negative, noninflamed eyes were compared for presence of cytokines IL-6, IL12, interferon gamma using enzyme-linked immunosorbent assay techniques, and CMV DNA (by polymerase chain reaction). Results: IRU eyes (11 patients, 18 samples) had the highest levels of IL-12 (median 48 pg/mL), moderate levels of IL-6 (median 146 pg/mL), and low but significant interferon gamma (median 15 pg/mL), compared to controls (P < 0.01). All uveitis eyes tested (9/9) were CMV DNA negative. In contrast, active CMV retinitis eyes were CMV DNA positive, had higher levels of IL-6 (median 349 pg/mL) (25 patients, 41 samples) than both control (P = 0.0001) and uveitis eyes (P = 0.048), similar levels of interferon gamma (median 27 pg/mL) to uveitis eyes, but less IL-12 (median 0 pg/mL) than uveitis eyes. Conclusions: Inflammatory IRU can be differentiated from active CMV retinitis by the presence of IL-12, less IL-6, and absence of detectable CMV replication.

Retinal Blood Flow Measurements in Branch Retinal Vein Occlusion Using Scanning Laser Doppler Flowmetry

PURPOSE To determine capillary blood flow measurements in eyes with branch retinal vein occlusion using a scanning laser Doppler flowmeter. METHODS Retinal capillary blood flow in branch retinal vein occlusion areas and corresponding ipsilateral nonbranch retinal vein occlusion areas, 11 equivalent areas of the contralateral fellow eye of 12 consecutive untreated branch retinal vein occlusion patients, and 16 eyes of 11 age-matched normal control subjects were measured with scanning laser Doppler flowmetry. A template consisting of eight squares, each with a field of 100 x 100 microm (10 x 10 pixel) with space interval of 500 microm equidistant horizontally and vertically was used to obtain blood flow measurements in all subjects. Mean blood volume, flow, and velocity were obtained by averaging the mean values measured in each field. We avoided measurement over large retinal vessels to prevent the aliasing artifact of blood cells from moving faster than the sampling frequency. RESULTS Branch retinal vein occlusion areas have significantly decreased microvascular blood volume (P = .0009), flow (P = .02), and velocity (P = .016) compared with ipsilateral nonbranch retinal vein occlusion areas in the same eye. Branch retinal vein occlusion areas also have decreased blood volume (P = .001), flow (P = .0042), and velocity (P = .0044) compared with areas of contralateral fellow eyes of branch retinal vein occlusion subjects. Branch retinal vein occlusion areas have significantly decreased blood volume (P = .0012), flow (P = .008), and velocity (P = .02) compared with age-matched normal areas. CONCLUSION Average retinal blood volume, flow, and velocity in areas of branch retinal vein occlusion are significantly lower than in healthy retinas. The ability to noninvasively measure hemodynamic changes in the retinal capillary bed may be relevant to development of new therapies for retinovascular disease.

Characterization of reactivation of cytomegalovirus retinitis in patients healed after treatment with highly active antiretroviral therapy.

Purpose: To delineate the immune parameters associated with reactivation of cytomeg‐alovirus (CMV) retinitis in patients for whom highly active antiretroviral therapy (HAART) was not successful. Methods: Prospective, longitudinal observational study of a cohort of 102 patients with CMV retinitis treated with HAART and being followed up at the AIDS Ocular Research Unit of the University of California, San Diego from November 1995 to November 1998. The study included serial clinical and fundus photographic examinations with CD4 T‐lympho‐cyte counts and HIV viral load measurements. Results: Forty‐seven of the 102 patients with CMV retinitis responded to HAART. Thirty‐five of the patients were successfully withdrawn from anti‐CMV therapy. During a median follow‐up of 74.71 weeks (range, 4.86‐144 weeks) after discontinuation of anti‐CMV therapy, four patients experienced a reactivation of CMV retinitis. In each case, the CD4 count decreased before reactivation to a median of 31.5 cells/mm3 (mean, 31.25 cells/mm3; range, 23‐39 cells/mm3). The association between the CD4 count decreasing to less than 50 cells/mm3 and reactivation of CMV retinitis was statistically significant (P < 0.0003). Conclusion: Four patients treated with HAART experienced reactivation of CMV retinitis as their CD4 count decreased. The threshold CD4 count below which reactivation of CMV retinitis occurred in patients for whom HAART was not successful appeared to be 50 cells/mm3. Despite an initial response to HAART, patients are still at risk for reactivation of CMV retinitis if their CD4 count decreases to less than 50 cells/mm3. The HIV viral load did not appear to predict CMV reactivation.

Original ArticlesRetinal blood flow measurements in branch retinal vein occlusion using scanning laser doppler flowmetry 1

PURPOSE To determine capillary blood flow measurements in eyes with branch retinal vein occlusion using a scanning laser Doppler flowmeter. METHODS Retinal capillary blood flow in branch retinal vein occlusion areas and corresponding ipsilateral nonbranch retinal vein occlusion areas, 11 equivalent areas of the contralateral fellow eye of 12 consecutive untreated branch retinal vein occlusion patients, and 16 eyes of 11 age-matched normal control subjects were measured with scanning laser Doppler flowmetry. A template consisting of eight squares, each with a field of 100 x 100 microm (10 x 10 pixel) with space interval of 500 microm equidistant horizontally and vertically was used to obtain blood flow measurements in all subjects. Mean blood volume, flow, and velocity were obtained by averaging the mean values measured in each field. We avoided measurement over large retinal vessels to prevent the aliasing artifact of blood cells from moving faster than the sampling frequency. RESULTS Branch retinal vein occlusion areas have significantly decreased microvascular blood volume (P = .0009), flow (P = .02), and velocity (P = .016) compared with ipsilateral nonbranch retinal vein occlusion areas in the same eye. Branch retinal vein occlusion areas also have decreased blood volume (P = .001), flow (P = .0042), and velocity (P = .0044) compared with areas of contralateral fellow eyes of branch retinal vein occlusion subjects. Branch retinal vein occlusion areas have significantly decreased blood volume (P = .0012), flow (P = .008), and velocity (P = .02) compared with age-matched normal areas. CONCLUSION Average retinal blood volume, flow, and velocity in areas of branch retinal vein occlusion are significantly lower than in healthy retinas. The ability to noninvasively measure hemodynamic changes in the retinal capillary bed may be relevant to development of new therapies for retinovascular disease.