Cytokines and Chemokines Involved in Acute Retinal Necrosis.

Purpose: To investigate which cytokines and chemokines are involved in the immunopathogenesis of acute retinal necrosis (ARN), and whether cytokine profiles are associated with clinical manifestations, such as visual outcome. Methods: Serum and aqueous humor (AH) samples of 19 patients with ARN were analyzed by multiplex immunoassay. Infectious controls consisted of 18 patients with rubella virus-associated Fuchs' uveitis and 20 patients with ocular toxoplasmosis all confirmed by intraocular fluid analyses. The control group consisted of seven paired AH and serum samples from seven noninflammatory control patients with age-related cataract. In each sample, 4 anti-inflammatory, 12 proinflammatory, 2 vascular, and 4 other immune mediators were measured. In addition, various clinical characteristics were assessed. Results: In ARN, 10 of the 22 mediators, including most proinflammatory and vascular mediators such as IL-6, IL-8, IL-18, MIF, MCP-1, Eotaxin, IP-10, IL-15, sICAM-1, and sVCAM-1, were significantly elevated when compared to all controls. In addition, one anti-inflammatory mediator (IL-10) was significantly elevated in ARN as compared to the controls. No association was found between the time of sampling and the extent and levels of immune mediator expression. Conclusions: The pathogenesis of ARN is characterized by the presence of predominantly proinflammatory cytokines and chemokines with high expression levels as compared to other infectious causes of uveitis. There are no indications for an obvious Th-1 or Th-17 pathway. The combined data suggest that immune mediator expression is related to severity of disease, which is more fulminant in ARN, rather than to a specific uveitis entity.

Intraocular biomarker identification in uveitis associated with juvenile idiopathic arthritis.

PURPOSE: To investigate the presence of biomarkers in aqueous humor (AH) from patients with uveitis associated with juvenile idiopathic arthritis (JIA). METHODS: AH (N = 73) AND SERUM (N = 105) SAMPLES FROM 116 CHILDREN WERE ANALYZED USING SURFACE ENHANCED LASER DESORPTION/IONIZATION TIME OF FLIGHT MASS SPECTROMETRY (SELDI-TOF MS). THE SAMPLES WERE DIVIDED INTO THE FOLLOWING GROUPS: JIA, silent chronic anterior uveitis (AU), other uveitis entities, and noninflammatory controls. Statistical biomarker identification was performed using the SELDI-ToF Biomarker Analysis Cluster Wizard followed by multivariate statistical analysis. Biochemical identification of biomarkers was performed by polyacrylamide gel protein separation, followed by liquid chromatography tandem mass spectrometry. ELISA was performed in a number of AH samples representing all four study groups. RESULTS: In the JIA group, one AH protein peak at mass/charge (m/z) 13,762 had qualitative and quantitative differences in expression compared with the other uveitis entities and the controls, but not to the group of silent chronic AU. Its quantitative expression in AH of patients with JIA and other silent chronic AU was positively associated with uveitis activity. The protein at m/z 13,762 in AH was identified as transthyretin (TTR). The TTR concentration in AH differed significantly between the study groups (P = 0.006) with considerably higher TTR concentrations in JIA and silent chronic AU samples positive for m/z 13,762 than those of the other uveitis and control groups. CONCLUSIONS: TTR is a potential intraocular biomarker of JIA- associated uveitis. Its role in the pathogenesis of silent chronic AU with and without arthritis needs further investigation.

Identification of new pathogens in the intraocular fluid of patients with uveitis.

PURPOSE: To determine infectious causes in patients with uveitis of unknown origin by intraocular fluids analysis. DESIGN: Case-control study. METHODS: Ocular fluids from 139 patients suspected of infectious uveitis, but negative for herpes simplex virus, varicella-zoster virus, cytomegalovirus, and Toxoplasma gondii by polymerase chain reaction and/or antibody analysis in intraocular fluids, were assessed for the presence of 18 viruses and 3 bacteria by real-time polymerase chain reaction (PCR). The ocular fluids from 48 patients with uveitis of known etiology or with cataract were included as controls. RESULTS: Positive PCR results were found for Epstein-Barr virus, for rubella virus, and for human herpesvirus 6 each in 1 patient and for human parechovirus in 4 patients. Of the human parechovirus-positive patients, 1 was immunocompromised and had panuveitis. The other 3 patients were immunocompetent and had anterior uveitis, all with corneal involvement. CONCLUSIONS: Human parechovirus might be associated with infectious (kerato)uveitis.

Intraocular and serum levels of vascular endothelial growth factor in acute retinal necrosis and ocular toxoplasmosis.

PURPOSE: To determine the intraocular and serum vascular endothelial growth factor (VEGF) levels in patients with acute retinal necrosis (ARN) and compare those with VEGF levels found in patients with ocular toxoplasmosis (OT). METHODS: Paired intraocular fluid and serum samples of 17 patients with ARN and of 16 patients with OT were analyzed by ELISA for VEGF levels, and the clinical records were reviewed. RESULTS: The mean intraocular VEGF levels in patients with ARN were higher than in patients with OT (P = 0.005), whereas the serum levels did not differ. Intraocular VEGF levels exceeded the serum levels in 8 of 17 patients (47%) with ARN compared with 1 of 16 patients (6%) with OT (P = 0.009). The group with high intraocular VEGF was associated with a more extensive retinitis and lower visual acuity at 3-month follow-up (P < 0.001 and P = 0.031, respectively). CONCLUSION: Intraocular VEGF levels were elevated in patients with ARN compared with OT patients. Our results suggest strong intraocular VEGF production in ARN, which might be of importance for the treatment of these patients.

Rubella virus-associated uveitis: clinical manifestations and visual prognosis.

PURPOSE: To investigate the clinical profile of patients with chronic anterior uveitis and intraocular analyses positive for intraocular Rubella virus infection and assess eventual similarities to Fuchs heterochromic uveitis (FHU). DESIGN: Retrospective case-control study. METHODS: Clinical records of 30 patients with anterior uveitis positive for intraocular antibody production against Rubella virus by Goldmann-Witmer coefficient determination and/or polymerase chain reaction were reviewed and compared with clinical records of 13 patients with chronic anterior uveitis of undetermined origin. Multiple variables were assessed and patient records were evaluated at onset and at one year after their first visit to the University Medical Center Utrecht. RESULTS: Patients with Rubella virus-associated uveitis were younger at time of initial ophthalmologic presentation (P = .014). Rubella virus-positive patients presented more frequently with unilateral ocular disease (P < .001), keratic precipitates (KPs; P = .014), iris atrophy and/or heterochromia (P = .051), associated vitreous opacities (P = .024), and cataract (P = .004). Also, the combination of KPs, absence of posterior synechiae, cataract, and vitreous opacities occurred more often in the Rubella virus-positive group (P = .026) and the presence of three or four of these criteria occurred more frequently in the Rubella virus-positive group (P = .004). CONCLUSIONS: Rubella virus causes a distinct clinical spectrum of ocular symptoms similar to the FHU syndrome, which suggests that Rubella virus might be involved in the pathogenesis of FHU.

Usefulness of aqueous humor analysis for the diagnosis of posterior uveitis.

PURPOSE: To assess the clinical usefulness of aqueous fluid analysis for the diagnosis and treatment of patients suspected of having infectious posterior uveitis (PU). DESIGN: Case-control study. PARTICIPANTS: From 2002 through 2005, 152 eyes from 152 patients with active PU (16 of whom were immunosuppressed) underwent diagnostic aqueous testing. As controls, 20 patients with Fuchs' heterochromic uveitis and 20 patients with age-related cataract were included. METHODS: Aqueous samples were examined by real-time polymerase chain reaction (PCR) and by pathogen-specific analysis of intraocular antibody production (Goldmann-Witmer coefficient [GWC]) for herpes simplex virus (HSV), varicella zoster virus (VZV), cytomegalovirus (CMV), and the parasite Toxoplasma gondii. MAIN OUTCOME MEASURES: Results of aqueous analysis and any adverse effects of aqueous sampling. Correlations between the results of aqueous testing and clinical characteristics as well as the treatment of patients. RESULTS: Of 152 patients, 44 (29%) had positive results for at least one diagnostic assay (37/136 [28%] immunocompetent and 7/16 [44%] immunocompromised patients). None of the controls had positive results using PCR or GWC. A positive result was obtained predominantly in patients with focal chorioretinitis (37/87 [40%]) and in extensive retinitis (7/9 [78%]), whereas in multifocal chorioretinitis, neuroretinitis, and retinal vasculitis only a few samples demonstrated positive results (2/19, 1/29, and 0/10, respectively). Of 37 immunocompetent PU patients with positive results, 28 (76%) cases were caused by T. gondii, whereas viral infections were most common in immunocompromised patients (5/7 [71%]). In immunocompetent and toxoplasmosis PU patients, GWC was the most informative assay (34/37 [92%] and 28/30 [93%], respectively), in contrast to immunosuppressed patients (PCR positive in 5/7 and GWC positive in 4/7). Independent of the immune status of patients, positive PCR results were observed more frequently in viral infections than in toxoplasmosis (P<0.001). As a consequence of aqueous analysis, change of treatment was necessary in 36 patients (24%). None of the patients experienced complications during or after aqueous sampling. CONCLUSIONS: Despite the posterior location of inflammation, aqueous analyses with PCR and GWC for HSV, VZV, CMV, and T. gondii revealed an infectious cause in 29% of patients with PU.

Diagnosis of ocular toxocariasis by establishing intraocular antibody production.

PURPOSE: To investigate the role of Toxocara canis in posterior uveitis of undetermined origin. DESIGN: Retrospective case-study. METHODS: Paired ocular fluid (47 aqueous humor [AH] and two vitreous fluids) and serum samples of 37 adults and 12 children with undetermined posterior uveitis were retrospectively analyzed for intraocular IgG antibody production against Toxocara canis by enzyme-linked immunosorbent assay and Goldmann-Witmer coefficient (GWC) determination. Previous diagnostic investigation by polymerase chain reaction and GWC for Herpes simplex virus, Varicella zoster virus, and Toxoplasma gondii had not provided a cause of the posterior uveitis. RESULTS: Three of 12 (25%) children showed intraocular IgG production against Toxocara canis. One child had vitritis, one presented with a low-grade uveitis and a peripheral retinal lesion, and the third had posterior uveitis and a chorioretinal scar. All three children had AH IgG titers exceeding those of the corresponding serum. In fact, two children had low Toxocara serum IgG titers (<1:32) and would have been considered seronegative upon routine serology screening. Intraocular antibody production against Toxocara canis was absent in all 37 adults, including five seropositive patients. CONCLUSIONS: Our results indicate that ocular toxocariasis is mainly a pediatric disease. Serological screening is not informative for the diagnosis of intraocular Toxocara infection. Toxocara GWC analysis, however, can be of value when diagnosing patients with posterior focal lesions or vitritis of unknown etiology.

Rubella virus is associated with fuchs heterochromic iridocyclitis.

PURPOSE: To determine whether rubella virus (RV) is involved in the pathogenesis of Fuchs heterochromic iridocyclitis (FHI). DESIGN: Retrospective patient-controlled study. METHODS: Intraocular immunoglobulin G production against RV, herpes simplex virus (HSV), varicella zoster virus (VZV), and Toxoplasma gondii was determined in the aqueous humor of 14 patients with FHI, 13 control subjects with herpetic uveitis anterior, and 19 control subjects with ocular toxoplasmosis by calculation of the Goldmann-Witmer coefficient (GWC). RESULTS: All patients and control subjects were seropositive for RV. Intraocular antibody production (GWC >3) against RV was found in 13 of 14 patients (93%) with FHI. Intraocular antibody production against HSV, VZV, or T gondii was not detected. None of the control subjects with herpetic uveitis anterior or with toxoplasma chorioretinitis had a positive GWC for rubella virus (P < .0001, Fisher exact test). CONCLUSION: Rubella virus, but not HSV, VZV, or T gondii, is associated with FHI.