Characterization of phenotype and cytokine profiles of T cell lines derived from vitreous humour in ocular inflammation in man

Outcomes of pars plana vitrectomy in the management and diagnosis of patients with infectious, non-infectious, and unidentified uveitis

PURPOSE

To present the outcomes of pars plana vitrectomy (PPV) in patients with infectious, non-infectious, and unidentified uveitis, focusing on visual and clinical outcomes, diagnostic yield, and surgery-related complications.

METHODS

This retrospective, single-center study included patients who underwent 23-gauge PPV for the management of uveitis and had at least 6 months of follow-up. Patients were divided into infectious, non-infectious, and unidentified uveitis groups based on definitive diagnosis after surgery. Etiologies of uveitis, indications for surgery, diagnostic yield, visual outcomes, presence of cystoid macular edema (CME), immunosuppressive drugs, intraoperative and postoperative complications, and repeated vitrectomies were reviewed.

RESULTS

This study included 62 eyes of 54 patients. Twenty eyes were diagnosed with infectious uveitis, 24 eyes with non-infectious uveitis, and 18 eyes with unidentified uveitis. The diagnostic yield of vitrectomy was 41.7%. Mean BCVA significantly improved at postoperative 1 month compared to baseline and remained stable at following time-points in all groups. The most common early postoperative complication was increased intraocular pressure (17%), and late complication was cataract (36%). Nine eyes underwent re-vitrectomy and the most common cause was retinal detachment with proliferative vitreoretinopathy (PVR).

CONCLUSION

PPV seems to be effective in diagnosing cases of unknown origin, improving visual acuity, and reducing the need for systemic immunosuppressive drugs. PVR is the most serious complication with poor prognosis that requires repeated surgery in patients with uveitis.

Vitreoretinal Surgery in Uveitis: From Old to New Concepts - A Review

PURPOSE

The aim of this article is to do a comprehensive literature review about the current role of pars plana vitrectomy in uveitis and in its different structural complications such as cystoid macular edema, epiretinal membrane, macular hole, and retinal detachment.

METHODS

This comprehensive literature review was performed based on a search on PubMed, BioMed Central, Science Open, and CORE databases, of relevant articles abording pars plana vitrectomy in uveitis.

DISCUSSION

Uveitis is a complex disease with multiple etiologies and pathogenic mechanisms. Therapeutic pars plana vitrectomy (PPV) may aid in uveitic structural complications such as cystoid macular edema, epiretinal membranes, macular hole, and retinal detachments even though some cases may present unpredictable visual outcomes. Diagnostic PPV with appropriate ancillary testing is also a valuable tool for the assessment and diagnosis of uveitis in a large proportion of patients.

CONCLUSION

Over the years, pars plana vitrectomy has undergone significant transformations since its invention nearly 5 decades ago, however, the quality of evidence in the literature regarding its use for uveitis has not improved in the same way. Even though some structural uveitis complications (as previously mentioned) may respond well to surgery, there is still a certain unpredictability regarding its visual outcomes. On the other hand, diagnostic vitrectomy with appropriate ancillary testing is also a valuable tool for the assessment and diagnosis of uveitis in a large proportion of patients.

Mechanisms of blood-retinal barrier disruption related to intraocular inflammation and malignancy

Blood-retinal barrier (BRB) disruption is a common accompaniment of intermediate, posterior and panuveitis causing leakage into the retina and macular oedema resulting in vision loss. It is much less common in anterior uveitis or in patients with intraocular lymphoma who may have marked signs of intraocular inflammation. New drugs used for chemotherapy (cytarabine, immune checkpoint inhibitors, BRAF inhibitors, EGFR inhibitors, bispecific anti-EGFR inhibitors, MET receptor inhibitors and Bruton tyrosine kinase inhibitors) can also cause different types of uveitis and BRB disruption. As malignant disease itself can cause uveitis, particularly from breast, lung and gastrointestinal tract cancers, it can be clinically difficult to sort out the cause of BRB disruption. Immunosuppression due to malignant disease and/or chemotherapy can lead to infection which can also cause BRB disruption and intraocular infection. In this paper we address the pathophysiology of BRB disruption related to intraocular inflammation and malignancy, methods for estimating the extent and effect of the disruption and examine why some types of intraocular inflammation and malignancy cause BRB disruption and others do not. Understanding this may help sort and manage these patients, as well as devise future therapeutic approaches.

CD83+ B cells alleviate uveitis through inhibiting DCs by sCD83

Soluble CD83 (sCD83) exerts immunosuppressive functions in many autoimmune diseases, including experimental autoimmune uveitis (EAU), but the cells and mechanisms involved are unclear. This study showed that CD83+ B cells were the main sources of sCD83. They alleviated the symptoms of EAU and decreased the percentage of T cells and DCs in the eyes and lymph nodes. These CD83+ B cells decreased IL-1β, IL-18 and IFN-γ secretion by DCs through sCD83. sCD83 interacted with GTPase Ras-related protein (Rab1a) in DCs to promote Rab1a accumulation in autolysosomes and inhibit mTORC1 phosphorylation and NLRP3 expression. Hence, CD83+ B cells play a regulatory role in EAU by secreting sCD83. The lack of regulation of CD83+ B cells might be an important factor leading to hyperimmune activation in patients with autoimmune uveitis. CD83+ B cells suppress activated DCs in uveitis, indicating the potential therapeutic role of CD83+ B cells in uveitis.

Elevated interleukin-10 levels in patients with ocular toxoplasmosis

In elderly patients, ocular toxoplasmosis is one of the most common etiologies of uveitis, which should be differentially diagnosed from ocular lymphoma, another common pathology of uveitis in older adults. The high level of interleukin (IL)-10 and an IL-10/IL-6 ratio higher than 1 (>1.0) are helpful parameters to diagnose ocular lymphoma. In this study, we used aqueous humor samples to detect 4 cases of ocular toxoplasmosis in patients with high levels of IL-10 and an IL-10/IL-6 ratio higher than 1. Our results show that ocular toxoplasmosis may be associated with increased cytokine levels in aqueous humor.

Touch-free optical technologies to streamline the production of T cell therapies

Currently approved adoptive T cell therapy relies on autologous (obtained from the same patient) T cells, which often suffer from poor quality that diminishes treatment efficacy. Due to the heterogeneous nature of T cell quality between and within patients, significant efforts are aimed at optimizing cell manipulation and growth conditions for potent T cell products. We believe that touch-free imaging and sensing technologies are critical to monitor single-cell features during T cell manufacturing to ensure consistent and optimally timed methods for cell manipulation and growth. Here, we discuss emerging label-free optical imaging and sensing methods, along with machine learning techniques that could enable in-line feedback to optimize T cell quality at multiple stages during manufacturing. These methods have the potential to streamline current workflow, accelerate the manufacture of safe high-quality T cell therapies, and improve our understanding of the dynamic, heterogeneous processes of T cell manufacturing.

Cytokine Changes in the Aqueous Humor in Rubella-Related Fuchs Heterochromic Iridocyclitis

This retrospective study is aimed at determining the correlation between cytokine levels and virus status in the aqueous humor of 38 patients with Fuchs heterochromic iridocyclitis (FHI) with/without a viral presence between May 2017 and January 2020. The levels of cytokines were analyzed in the groups with and without virus-related FHI. Among the patients, 50% had rubella virus, 5.26% had cytomegalovirus, and 2.63% had herpes simplex virus infections. The expression of interleukin-6 (IL-6) and IL-8 was significantly higher, and that of basic fibroblast growth factor (bFGF) was significantly lower in the virus-positive group than in the virus-negative group (P = 0.015, P = 0.001, and P = 0.001, respectively). Although there was no significant difference in the mean expression of vascular cell adhesion protein 1 (VCAM-1), IL-10, and vascular endothelial growth factor (VEGF), that of VCAM-1 and IL-10 was higher (M = 1338 and M = 1390, respectively; M = 6.225 and 10.600, respectively) and that of VEGF was lower (M = 134.5 and M = 38.70, respectively) in the virus-positive group than in the virus-negative group. Similar findings were observed for the expressions of IL-6, IL-8, and bFGF in the rubella-positive and rubella-negative groups. Viral presence was highly related to FHI, especially that of the rubella virus. High levels of inflammatory cytokines and low levels of neovascularization-related factors are involved in rubella-related FHI. These study findings could be helpful in the diagnosis and treatment of FHI.

Cytokines, chemokines and growth factors profile in human aqueous humor in idiopathic uveitis

To investigate which cytokines, chemokines and growth factors are involved in the immunopathogenesis of idiopathic uveitis, and whether cytokine profiles are associated with. Serum and aqueous humor (AH) samples of 75 patients with idiopathic uveitis were analyzed by multiplex immunoassay. Infectious controls consisted of 16 patients with ocular toxoplasmosis all confirmed by intraocular fluid analyses. Noninfectious controls consisted of 7 patients with Behçet disease related uveitis and 15 patients with sarcoidosis related uveitis. The control group consisted of AH and serum samples from 47 noninflammatory control patients with age-related cataract. In each sample, 27 immune mediators ± IL-21 and IL-23 were measured. In idiopathic uveitis, 13 of the 29 mediators, including most proinflammatory and vascular mediators such as IL-6, IL-8, IL-12, G-CSF, GM-CSF, MCP-1, IP-10, TNF-α and VEGF, were significantly elevated in the aqueous humor when compared to all controls. Moreover, IL-17, IP-10, and IL-21, were significantly elevated in the serum when compared to all controls. We clustered 4 subgroups of idiopathic uveitis using a statistical analysis of hierarchical unsupervised classification, characterized by the order of magnitude of concentrations of intraocular cytokines. The pathogenesis of idiopathic uveitis is characterized by the presence of predominantly proinflammatory cytokines and chemokines and vascular endothelial growth factor with high expression levels as compared to other causes of uveitis. There are indications for obvious Th-1/ IL21-Th17 pathways but also IL9-Th9 and increased IFN-γ-inducing cytokine (IL12) and IFN-γ-inducible CXC chemokine (IP-10). The combined data suggest that immune mediator expression is different among idiopathic uveitis. This study suggests various clusters among the idiopathic uveitis group rather than one specific uveitis entity.

Soluble CD83 Regulates Dendritic Cell-T Cell Immunological Synapse Formation by Disrupting Rab1a-Mediated F-Actin Rearrangement

Dendritic cell-T cell (DC-T) contacts play an important role in T cell activation, clone generation, and development. Regulating the cytoskeletal protein rearrangement of DCs can modulate DC-T contact and affect T cell activation. However, inhibitory factors on cytoskeletal regulation in DCs remain poorly known. We showed that a soluble form of CD83 (sCD83) inhibited T cell activation by decreasing DC-T contact and synapse formation between DC and T cells. This negative effect of sCD83 on DCs was mediated by disruption of F-actin rearrangements, leading to alter expression and localization of major histocompatibility complex class II (MHC-II) and immunological synapse formation between DC and T cells. Furthermore, sCD83 was found to decrease GTP-binding activity of Rab1a, which further decreased colocalization and expression of LRRK2 and F-actin rearrangements in DCs, leading to the loss of MHC-II at DC-T synapses and reduced DC-T synapse formation. Further, sCD83-treated DCs alleviated symptoms of experimental autoimmune uveitis in mice and decreased the number of T cells in the eyes and lymph nodes of these animals. Our findings demonstrate a novel signaling pathway of sCD83 on regulating DC-T contact, which may be harnessed to develop new immunosuppressive therapeutics for autoimmune disease.

Response of Trametes hirsuta to hexavalent chromium promotes laccase-mediated decolorization of reactive black 5

The recalcitrant azo dyes combined with heavy metals constitute a major challenge for the bioremediation of industrial effluents. This study aimed to investigate the effect and mechanism of action of a white-rot fungus Trametes hirsuta TH315 on the simultaneous removal of hexavalent chromium [Cr(VI)] and azo dye (Reactive Black 5, RB5). Here, this study discovered that toxic Cr(VI) (1 mM) greatly promoted RB5 decolorization (from 57.15% to 83.65%) by white-rot fungus Trametes hirsuta with high Cr(VI)-reducing ability (>96%), resulting in the simultaneous removal of co-contaminants. On the basis of transcriptomic and biochemical analysis, our study revealed that the oxidative stress in co-contaminants mainly caused by Cr(VI), and a number of dehydrogenases and oxidases showed up-regulation in response to Cr(VI) stress. It was noteworthy that the oxidative stress caused by Cr(VI) in co-contaminants can both significantly induce glutathione S-transferase and laccase expression. Glutathione S-transferase potentially involved in antioxidation against Cr(VI) stress. Laccase was found to play a key role in RB5 decolorization by T. hirsuta. These results suggested that the simultaneous removal of co-contaminants by T. hirsuta could be achieved with Cr(VI) exposure. Overall, the elucidation of the molecular basis in details will help to advance the general knowledge about the fungus by facing harsh environments, and put forward a further possible application of fungi on environmental remediation.

CD4- and CD8-expressing cells in the chambers of normal, cataract and uveitic eyes: A comparative study in dogs

The main aims of this study were to determine whether CD4⁺ and CD8⁺ cells are present in the normal chambers of the eye in dogs and to verify the hypothesis that uncomplicated cataract may be associated with the local recruitment of CD4⁺ and CD8⁺ cells. The presence of CD4⁺ and CD8⁺ cells was detected in aqueous humor (AH) of normal and cataract eyes. The study did not reveal differences in the percentage and absolute number of CD4⁺ cells between normal and cataract eyes. However, the values of these parameters in AH from cataract eyes were approximately 2- and 3-fold higher than in normal eyes, respectively. The mean percentage and absolute count of CD8⁺ cells increased approximately by 2.7- and 6-fold, respectively, in AH samples from cataract eyes compared to normal ones. The absolute count of CD4⁺ and CD8⁺ cells in AH of uveitic eyes was approximately 5- and 3-fold higher than in cataract eyes. The results indicate that CD4⁺ and CD8⁺ cells occur constitutively in the normal chambers of the eye in dogs. However, it should be pointed out that both of these cell populations appeared in trace amounts. The development of uncomplicated cataract in dogs may not be immunologically neutral in terms of the local immune response, but it may be associated with the recruitment of CD8⁺ cells into the eye chambers. This event does not seem to be of an inflammatory nature because it appears on a scale a few times smaller than in the course of uveitis.

I-alowCD11bhigh DC Regulates the Immune Response in the Eyes of Experimental Autoimmune Uveitis

Regulatory dendritic cells (DC_reg) have been reported to be a negative regulator in the immune response. These cells are widely distributed in the liver, spleen, and lung. However, the status and function of DC_reg in the eyes and disease are still not very clear. Herein, we found that the number of I-a^lowCD11b^high DC increased in the eye and spleen at the recovery stage of experimental autoimmune uveitis (EAU), which is a mouse model for autoimmune uveitis. These cells expressed lower levels of CD80, CD86, and CD54 than the mature DCs and expressed interleukin 10 (IL-10), indoleamine 2,3-dioxygenase (IDO), and transforming growth factor beta (TGF-β) as well. Moreover, these DC_reg can regulate the development of EAU by promoting CD4⁺CD25⁺Foxp3⁺ regulatory T cells. The increased interferon-gamma (IFN-γ) in the aqueous humor of EAU participates in inducing DC_reg to alleviate the symptom of EAU. Furthermore, DC_reg was found to exist in the eyes of normal mice. Aqueous humor, containing a certain concentration of IL-10, TGF-β, prostaglandin E2 (PGE2), IDO, and nitric oxide (NO), induced the tolerance of DC_reg in normal eyes. It can be concluded that DC_reg exists in the eyes and plays a protective role in inflamed eyes. These DC_reg induced by IFN-γ might be used as a strategy to develop therapy for EAU management.

Macular edema associated with non-infectious uveitis: pathophysiology, etiology, prevalence, impact and management challenges

Macular edema (ME) is the most common sight-threatening complication in uveitis. The diagnostic and therapeutic management of the uveitic macular edema (UME) might be challenging due to the complex diagnostic workup and the difficulties physicians face to find the underlying cause, and due to its usually recurrent nature and the fact that it can be refractory to conventional treatment. Some of the mild cases can be treated with topical steroids, which can be combined with non-steroid anti-inflammatory drugs. However, immunomodulators such as methotrexate, tacrolimus, azathioprine, cyclosporine and mycophenolate mofetil together with anti-tumor necrosis factor-α (anti-TNF alpha) monoclonal antibodies such as adalimumab and infliximab, may be required to control the inflammation and the associated ME in refractory cases, or when an underlying disease is present. This review of the literature will focus mostly on the non-infectious UME.

The role of ocular dendritic cells in uveitis

Dendritic cells (DCs) act as a bridge between innate and adoptive immunity. They are widely distributed in various tissues and organs. Resident ocular DCs are found in the peripheral margins and juxtapapillary areas of the retina, usually in an immature state. During inflammation, DCs are activated and participate in the development of uveitis, an ocular inflammatory disease. Herein, the characteristics and status of DCs in uveitis, the possible factors affecting the status of DCs, and the clinical methods for detecting the DCs in patients are described.

CD83+ CCR7+ NK cells induced by interleukin 18 by dendritic cells promote experimental autoimmune uveitis

Natural killer (NK) cells have been reported to play a pathological role in autoimmune uveitis. However, the mechanisms regarding NK cells in uveitis and factors that affect NK-cell activation in this condition remain unclear. Here, we report that the number of CD3- NK1.1+ CD83+ CCR7+ cells is increased in the inflamed eyes within a mouse model of experimental autoimmune uveitis (EAU), and these cells express elevated levels of NKG2D, CD69 and IFN-γ. Adoptively transferring CD83+ CCR7+ NK cells aggravates EAU symptoms and increases the number of CD4+ IFN-γ+ T cells and dendritic cells (DCs) within the eye. These CD83+ CCR7+ NK cells then promote the maturation of DCs and IFN-γ expression within T cells as demonstrated in vitro. Furthermore, IL-18, as primarily secreted by DCs in the eyes, is detected to induce CD83+ CCR7+ NK cells. In EAU mice, anti-IL-18R antibody treatment also decreases retinal tissue damage, as well as the number of infiltrating CD83+ CCR7+ NK cells, T cells and DCs in the inflamed eyes and spleens of EAU mice. These results suggest that CD83+ CCR7+ NK cells, as induced by IL-18 that primarily secreted by DCs, play a critical pathological role in EAU. Anti-IL-18R antibody might serve as a potential therapeutic agent for uveitis through its capacity to inhibit CD83+ CCR7+ NK cells infiltration.

Update in treatment of uveitic macular edema

Macular edema (ME) represents the most common cause for visual loss among uveitis patients. The management of uveitic macular edema (UME) may be challenging, due to its often recalcitrant nature. Corticosteroids remain the mainstay of treatment, through their capability of effectively controlling inflammation and the associated ME. Topical steroids may be effective in milder cases of UME, particularly in edema associated with anterior uveitis. Posterior sub-Tenon and orbital floor steroids, as well as intravitreal steroids often induce rapid regression of UME, although this may be followed by recurrence of the pathology. Intra-vitreal corticosteroid implants provide sustained release of steroids facilitating regression of ME with less frequent injections. Topical nonsteroidal anti-inflammatory drugs may provide a safe alternative or adjuvant therapy to topical steroids in mild UME, predominantly in cases with underlying anterior uveitis. Immunomodulators including methotrexate, mycophenolate mofetil, tacrolimus, azathioprine, and cyclosporine, as well as biologic agents, notably the anti-tumor necrosis factor-α monoclonal antibodies adalimumab and infliximab, may accomplish the control of inflammation and associated ME in refractory cases, or enable the tapering of steroids. Newer biotherapies have demonstrated promising outcomes and may be considered in persisting cases of UME.

Total glucosides of paeony suppresses experimental autoimmune uveitis in association with inhibition of Th1 and Th2 cell function in mice

Total glucosides of paeony (TGP) are active components extracted from the roots of Paeonia lactiflora Pall. In this study, we investigated the role and mechanisms of TGP in experimental autoimmune uveitis (EAU) model of mice. The C57BL/6 mice were randomly divided into three groups: sham group, EAU-control group, and EAU-TGP group. Clinical score of images of the eye fundus were taken on 7, 14, 21, and 28 days after induction of EAU. The concentrations of proinflammatory cytokines in intraocular fluid were measured at 14 days after EAU induction with the use of a multiplex assay system. Flow cytometry was used to analyze the frequency of CD4+, CD8+, interferon-gamma (IFN-γ), and CD4+/CD8+ ratio in spleen and lymph nodes. Western blotting was used to measure expressions of mitogen-activated protein kinase (MAPK) pathway-related proteins in retina. Clinical scores for uveitis were lower in TGP-treated EAU mice than those without TGP treatment. Importantly, the concentrations of cytokines induced by T-helper 1 (Th1) and T-helper 2 (Th2) cells in intraocular fluid were reduced in EAU mice treated with TGP. Furthermore, the frequency of CD4+, IFN-γ, and CD4+/CD8+ ratio was decreased and the frequency of CD8+ was increased in spleen and lymph nodes of mice treated with TGP. The anti-inflammatory effects of TGP were mediated by inhibiting the MAPK signaling pathways. Our results showed that TGP suppressed uveitis in mice via the inhibition of Th1 and Th2 cell function. Thus, TGP may be a promising therapeutic strategy for uveitis, as well as other ocular inflammatory diseases.

Soluble CD83 Alleviates Experimental Autoimmune Uveitis by Inhibiting Filamentous Actin-Dependent Calcium Release in Dendritic Cells

Soluble CD83 (sCD83) is the extracellular domain of the membrane-bound CD83 molecule, and known for its immunoregulatory functions. Whether and how sCD83 participates in the pathogenesis of uveitis, a serious inflammatory disease of the eye that can cause visual disability and blindness, is unknown. By flow cytometry and imaging studies, we show that sCD83 alleviates experimental autoimmune uveitis (EAU) through a novel mechanism. During onset and recovery of EAU, the level of sCD83 rises in the serum and aqueous humor, and CD83⁺ leukocytes infiltrate the inflamed eye. Systemic or topical application of sCD83 exerts a protective effect by decreasing inflammatory cytokine expression, reducing ocular and splenic leukocyte including CD4⁺ T cells and dendritic cells (DCs). Mechanistically, sCD83 induces tolerogenic DCs by decreasing the synaptic expression of co-stimulatory molecules and hampering the calcium response in DCs. These changes are caused by a disruption of the cytoskeletal rearrangements at the DC–T cell contact zone, leading to altered localization of calcium microdomains and suppressed T-cell activation. Thus, the ability of sCD83 to modulate DC-mediated inflammation in the eye could be harnessed to develop new immunosuppressive therapeutics for autoimmune uveitis.

Immune Profiling of T Cells Infiltrating Vitreous Humor in Tubercular Uveitis

PURPOSE

To assess cellular composition and local cytokine response in vitreous humor of tubercular uveitis.

METHODS

Cells were collected from vitreous cassettes and peripheral blood of 8 tubercular uveitis and 5 control subjects, undergoing vitrectomy and analyzed by flow cytometry for cellular composition, activation status, proinflammatory cytokine expression, and uptake of TLR9 ligand, CpG ODN 2216.

RESULTS

CD3 + T cells with equal proportion of CD4+ and CD8 + T cells formed major fraction of infiltrating cells. The vitreous humor showed higher expression of recent activation marker, CD69, and proinflammatory cytokines, IFN-γ and IL-17A, in CD4 + T cells as compared to peripheral blood. Lastly, intraocular CD4 + T cells showed reduced uptake of ODN 2216 than peripheral blood.

CONCLUSIONS

Our results indicate that local antigenic stimuli trigger T cell infiltration and activation of CD4 + T cells that are hyporesponsive to TLR9 stimulation. These infiltrating T cells might be responsible in further aggravating ocular inflammation.

Fuchs' Uveitis Syndrome: No Longer a Syndrome?

PURPOSE

Rubella virus (RV) has a central role in the etiopathogenesis of Fuchs' uveitis syndrome (FUS). We aim to offer new insights by comprehensive analysis of recent laboratory and epidemiologic data.

METHODS

We conducted a literature search for laboratory data and papers on etiopathogenesis.

RESULTS

Aqueous humour samples of FUS patients show immunoreactivity to RV, in a specific and sensitive manner. Identification of RV genome confirm intraocular infection in a subset of FUS patients. Epidemiologic findings further support causality. The clinical spectrum of RV-associated uveitis is similar but not identical to FUS. FUS eyes exhibit a predominance of CD8 + T cells, high IFN-? and IL-10 levels.

CONCLUSIONS

RV is the leading cause of FUS. Cytokine-based findings mirror a viral etiology and chronic low-grade inflammation. RV-associated FUS represents a common pathway of intraocular RV inoculation after congenital or acquired infection. Other causes, including HSV and CMV, may lead to FUS.

Role of dendritic cell subsets in immunity and their contribution to noninfectious uveitis

Dendritic cells (DCs) are a heterogeneous population. Murine DCs consist of conventional DCs (cDCs) and plasmacytoid DCs (pDCs). In humans, the analogous populations are myeloid DCs (mDCs) and pDCs. Though distinct in phenotypes and functions, studies have shown that these DC subsets may interact or "crosstalk" during immune responses. For example, cDCs may facilitate pDC maturation, and pDCs may enhance antigen presentation of cDCs in certain pathogenic conditions or even take on a cDC phenotype themselves. The role of DCs in noninfectious uveitis has been studied primarily in the experimental autoimmune uveitis mouse model and to a more limited extent in patients. Recent evidence shows that the number, phenotype, and function of DC subsets are altered in this disease. We provide an overview of selected recent developments of pDCs and cDCs/mDCs, with special attention to their interaction and the dual roles of DC subsets in noninfectious uveitis.

Evaluation of microincision vitrectomy surgery using wide-viewing system for complications with ocular sarcoidosis

We evaluate the outcomes of microincision vitrectomy surgery (MIVS) using wide-viewing system for complications with ocular sarcoidosis resistance to medical treatment.Consecutive clinical records of 24 eyes (19 patients) with complications of ocular sarcoidosis underwent MIVS between April 2010 and December 2013 were retrospectively reviewed. MIVS and phacoemulsification were performed in 18 eyes and MIVS only in 6 eyes. Best-corrected visual acuity (BCVA), inflammation scores in the anterior segment and in the posterior segment, and central retinal thickness (CRT) of eyes with cystoid macular edema (CME) before surgery and after 1 week, 1, 3, 6, and 12 months were evaluated.LogMAR (log of the minimum angle of resolution) converted from BCVA was improved in 83.3% after 12 months and 66.7% showed improvement of more than 2 lines. The mean LogMAR was significantly improved from 1.14 ± 1.18 to 0.36 ± 0.79 in all eyes and 0.83 ± 0.86 to 0.23 ± 0.41 in eyes with MIVS and phacoemulsification, although no improvement was observed in eyes with MIVS only. Significant decrease of the mean anterior inflammation score was observed after 1 month in eyes with MIVS only and after 12 months in eyes with MIVS and phacoemulsification, and the mean posterior inflammation scores decreased after 1 week in all eyes. In eyes with preoperative CME, mean CRT was significantly decreased from 1 week after surgery. There was no case in which ocular inflammation was exacerbated by surgical stress. Improvement of visual acuity and resolution of ocular inflammation could be achieved by MIVS using wide-viewing system for complications of ocular sarcoidosis.

Primary intraocular lymphoma

Primary intraocular lymphoma (PIOL) is an ocular malignancy that is a subset of primary central system lymphoma (PCNSL). Approximately one-third of PIOL patients will have concurrent PCNSL at presentation, and 42-92% will develop PCNSL within a mean of 8-29 months. Although rare, the incidence has been rising in both immunocompromised and immunocompetent populations. The majority of PIOL is diffuse large B-cell lymphoma, though rare T-cell variants are described. Recently, PIOL has been classified by main site of involvement in the eye, with vitreoretinal lymphoma as the most common type of ocular lymphoma related to PCNSL. Diagnosis remains challenging for ophthalmologists and pathologists. PIOL can masquerade as noninfectious or infectious uveitis, white dot syndromes, or occasionally as other neoplasms such as metastatic cancers. Laboratory diagnosis by cytology has been much aided by the use of immunocytochemistry, flow cytometry, biochemical finding of interleukin changes (IL10:IL6 ratio > 1), and cellular microdissection with polymerase chain reaction amplification for clonality. Use of several tests improves the diagnostic yield. Approaches to treatment have centered on systemic methotrexate-based chemotherapy, often with cytarabine (Ara-C) and radiotherapy. Use of intravitreal chemotherapy with methotrexate (0.4 mg/0.1 mL) is promising in controlling ocular disease, and intravitreal rituximab (anti-CD20 monoclonal antibody) has also been tried. Despite these advances, prognosis remains poor.

High dose infliximab in the treatment of refractory uveitis: does dose matter?

Background. Infliximab (INF) has been shown to be beneficial in treating refractory uveitis, however, no data exist on optimal dosing and the efficacy of higher dosing. Objectives. To compare the efficacy of low-dose (LD) (<10 mg/kg), moderate-dose (MD) (≥10–15 mg/kg), and high-dose (HD) INF (≥15–20 mg/kg) in the treatment of uveitis. Methods. Retrospective chart review children with uveitis diagnosed at Childrens Hospital Los Angeles and Millers Children's Hospital, CA, USA. Results. Of the 34 INF-treated children, 6 patients received LD, 19 received MD, and 9 received HD. Average disease duration prior to therapy was 10.6, 24.6, and 37.1 months each group, respectively. Topical steroids were discontinued after an average of 3 months, 9.5 months, and 10.2 months in the LD, MD, and HD groups, respectively. We found that 66% of patients receiving LD, 42% of MD, and 66% receiving HD INF failed therapy and required either dose escalation or alternate medication for disease control. Conclusions. INF is beneficial in the treatment of uveitis, and dose escalation up to 4 times above the approved dose is often necessary to achieve disease control in patients with uveitis. Doses < 10 mg/kg every 4 weeks may not be sufficient to control disease.

Intermediate uveitis and alopecia areata: is there a relationship? Report of 3 pediatric cases

Three previously healthy children, aged 5, 8, and 15 years, with idiopathic intermediate uveitis (IU) and alopecia areata (AA) are described. These are the first 3 cases of which we are aware with this coexistence. The results of extensive diagnostic evaluations were negative in all 3 cases. AA preceded the diagnosis of bilateral IU in 1 child and followed within several months after IU diagnosis in 2 children. The severity of uveitis ranged from mild to sight-threatening, and hair loss ranged from local lesions in 2 cases to total alopecia in 1 case. Pathogenesis of both diseases is discussed. Theoretically, the coexistence of IU and AA might be based on the similarities in their complex pathogenesis. However, more research is needed to evaluate if the coexistence is based on an association between 2 autoimmune disorders or is a coincidence.

Th1- and Th2-related chemokine and chemokine receptor expression on the ocular surface in endotoxin-induced uveitis

PURPOSE

To determine whether the ocular surface inflammation in uveitis mimics or counteracts intraocular inflammatory pathways by directly comparing T-helper (Th) lymphocytes Th1 and Th2 markers in conjunctival and ciliary body expression in endotoxin-induced uveitis (EIU). This study used the following inflammatory markers: chemokine receptor, CC chemokine receptor 4 (CCR4), and its ligand, macrophage-derived chemokine (MDC), to evaluate Th2 participation; chemokine receptor, CCR5, to evaluate the Th1 system; and its ligand, regulated on activation normal T cell expressed and secreted (RANTES), to evaluate both Th1 and Th2 systems.

METHODS

Immunohistochemistry and real-time polymerase chain reaction (RT-PCR) were used to compare protein and RNA expression of CCR4, MDC, CCR5, and RANTES in the conjunctiva and ciliary body in EIU 6 h and 24 h after the lipopolysaccharide (LPS) injection and in control (without injection) Lewis rats.

RESULTS

Immunohistochemistry with CCR5, RANTES, and MDC showed an increase in fluorescent staining in the conjunctiva and ciliary body in the rats with uveitis compared to the control rats. For CCR4, immunostaining was comparable in the conjunctiva and ciliary body and did not show any clear differences between control rats and rats with EIU. For RANTES, MDC, and CCR5, RT-PCR showed a significantly higher RNA expression in conjunctiva and in ciliary body at 6 h compared to 24 h and controls. For CCR4, RT-PCR did not illustrate any significant differences in conjunctiva and in ciliary body between all groups of animals.

CONCLUSIONS

Protein and RNA expressions of RANTES, MDC, and CCR5 were higher in EIU rats than in control rats in the conjunctiva and ciliary body whereas the CCR4 level was not modified in the conjunctiva and ciliary body of EIU rats when compared to controls. Th1 activation seemed to predominate in this model with high levels of CCR5 expression and no increased expression of CCR4, but Th2 participation with MDC was noted. The expression of RANTES, MDC, CCR4 and CCR5 in EIU was quite similar between the conjunctiva and the ciliary body, so conjunctival inflammation might reproduce the intraocular inflammation, probably generated by local extension and diffusion in this model. If the ocular surface mimics intraocular inflammatory pathways, the conjunctiva may provide a new and easier access for uveitis studies.

Lentiviral-vector-mediated expression of murine IL-1 receptor antagonist or IL-10 reduces the severity of endotoxin-induced uveitis

Uveitis is a sight threatening inflammatory disorder that remains a significant cause of visual loss. We investigated lentiviral gene delivery of interleukin 1 receptor antagonist (IL-1ra) or interleukin (IL)-10 to ameliorate murine endotoxin-induced uveitis (EIU). An human immunodeficiency virus-1-based vector containing the mIL-1ra or mIL-10 cDNA demonstrated high expression of biologically active cytokine. Following administration of Lenti.GFP into the anterior chamber, transgene expression was observed in corneal endothelial cells, trabecular meshwork and iris cells. To treat EIU, mice were injected with Lenti.IL-1ra, Lenti.IL-10 or a combination of these. EIU was induced 14 days after vector administration and mice were culled 12 h following disease induction. Lenti.IL-1ra or Lenti.IL-10-treated eyes showed significantly lower mean inflammatory cell counts in the anterior and posterior chambers compared with controls. The aqueous total protein content was also significantly lower in treated eyes, demonstrating better preservation of the blood-ocular barrier. Furthermore, the treated eyes showed less in vivo fluorescein leakage from inner retinal vessels compared with controls. The combination of both IL-1ra and IL-10 had no additive effect. Thus, lentiviral gene delivery of IL-1ra or IL-10 significantly reduces the severity of experimental uveitis, suggesting that lentiviral-mediated expression of immunomodulatory genes in the anterior chamber offers an opportunity to treat uveitis.

Th1 and Th2 responses on the ocular surface in uveitis identified by CCR4 and CCR5 conjunctival expression

PURPOSE

To investigate CC chemokine receptor 4 (CCR4) and CC chemokine receptor 5 (CCR5) expression, known to be related to the Th2 and Th1 inflammatory pathways, respectively, and human leukocyte antigen-D related (HLA-DR) antigens as hallmarks for ocular surface inflammation in patients with uveitis using conjunctival impression cytologic specimens.

DESIGN

Case-controlled study.

METHODS

Conjunctival impression cytologic specimens were obtained from patients with anterior uveitis (n = 26), and their inflammatory profile was compared with those of patients with vernal keratoconjunctivitis (VKC; n = 24), keratoconjunctivitis sicca (KCS; n = 17), and normal subjects (n = 17). Expressions of CCR4, CCR5, and HLA-DR were analyzed using flow cytometry and were expressed by determining the percentage of cells expressing the markers in the conjunctival epithelium.

RESULTS

CCR4 was overexpressed in the uveitis group (mean, 19.8% +/- 19.7% of positive cells) and in the VKC group (24.7% +/- 20.1%). CCR5 was expressed only weakly in uveitis patients (6.4% +/- 13.1%) and in the normal subjects (2.4% +/- 2.4%). HLA-DR expression by conjunctival cells was increased in the uveitis patients (57.4% +/- 21.1%) and in the KCS group (52.4% +/- 12.1%) compared with the VKC group (23.9% +/- 26.8%; P < .001) and normal subjects (22.1% +/- 19.1%; P < .001).

CONCLUSIONS

CCR4, classically related to the Th2 system, and HLA-DR both were overexpressed by the conjunctival epithelium in uveitis patients, whereas CCR5, related to the Th1 system, was expressed weakly in uveitis patients. These preliminary results seem to suggest an involvement of the Th2 system on the ocular surface in uveitis. Exploration of the ocular surface in uveitis may represent a new way to understand better the immune pathways involved in this complex disease.

Protocol for the use of polymerase chain reaction in the detection of intraocular large B-cell lymphoma in ocular samples

To determine the usefulness of polymerase chain reaction (PCR) analyses in the diagnosis of lymphoid infiltrate cells in ocular samples, PCR was performed using oligonucleotide primers specific for immunoglobulin heavy chain rearrangement at framework 2, framework 3, and t(14;18) translocation of the bcl-2 gene. These were used to successfully generate amplicons of 220 to 230 bp, 110 to 120 bp, and 175 to 200 bp, respectively. After PCR amplification, primers directed against the t(14;18) detected 10 pg of B-cell lymphoma DNA. PCR against Fr2 and Fr3 IgH rearrangement detected 10 fg and 10 pg in the seminested PCR, respectively. Conventional pathological methods were highly accurate at establishing the correct final diagnosis in formalin-fixed, paraffin-embedded samples but were much less sensitive and predictive in cytological specimens of intraocular fluid. A combination of the three PCR reactions was an equally successful diagnostic approach on paraffin-embedded samples, whereas single PCR reactions did not significantly improve diagnosis over histopathological diagnostic techniques. Thus, a combination of PCR reactions is useful in the detection of B-cell monoclonality, aids the differentiation between lymphomatous and inflammatory infiltrates, and is more powerful as a diagnostic method than single PCR or conventional cytopathology for lymphoid infiltrates in ocular fluid aspirates.

A suggestive association of fuchs heterochromic cyclitis with cytotoxic T cell antigen 4 gene polymorphism

BACKGROUND

Fuchs heterochromic cyclitis (FHC) is a chronic inflammatory eye disease, usually presenting as unilateral anterior uveitis. Up to date no disease susceptibility genes have been described for FHC.

METHODS

The allele frequency of HLA DRB1 and DQB1, polymorphisms of the tumour necrosis factor (TNF) alpha promoter region (-376, -308, -238), the promoter (-318), first exon (+49) and (AT)n repeat polymorphism of the cytotoxic T cell antigen 4 (CTLA4) gene were analysed in 44 FHC patients and 139 healthy controls.

RESULTS

The CTLA4 -318 C/T genotype was increased in FHC patients [odds ratio (OR) 3.0, 95% confidence interval (CI) 1.4-6.5], as well as long CTLA4 (AT)n microsatellite alleles with more than 16 AT repeats (OR 2.6, 95% CI 1.3-5.3). A trend towards the -308 G/A TNF-alpha genotype was found in the patient cohort, whereas no difference in HLA class II allele distribution was observed.

CONCLUSION

CTLA4 but not TNF-alpha or HLA class II DRB1 and DQB1 may represent a candidate gene for disease susceptibility in FHC.

Ocular complications of childhood rheumatic diseases: uveitis

Ocular involvement is common in pediatric rheumatologic diseases, supporting the concept that these conditions cannot be understood simply as isolated entities, but rather as multisystem disorders. The reasons for the breach of the eye-brain barrier and the targeting of the usually well-shielded eye during a pan-inflammatory process remains unclear. Pediatric rheumatologists should become familiar with these ocular disorders, because as important members of the treatment team, they manage more serious cases of inflammatory eye disease. A close collaboration between the treating rheumatologist and the ophthalmologist is essential to prevent potentially devastating outcomes. Therapeutic interventions such as topical steroids, systemic immunosuppressants, and biologics must balance the necessity of controlling ocular inflammation and the adverse effects of these treatments on a growing child.

Cytokines and chemokines in uveitis: is there a correlation with clinical phenotype?

Uveitis is a general term for intraocular inflammation and includes a large number of clinical phenotypes. As a group of disorders, it is responsible for 10% of all registered blind patients under the age of 65 years. Immune-mediated uveitis may be associated with a systemic disease or may be localized to the eye. The pro-inflammatory cytokines interleukin (IL)-1beta, IL-2, IL-6, interferon-gamma and tumor necrosis factor-alpha have all been detected within the ocular fluids or tissues in the inflamed eye together with others, such as IL-4, IL-5, IL-10 and transforming growth factor-beta. The chemokines IL-8, monocyte chemoattractant protein-1, macrophage inflammatory protein (MIP)-1alpha, MIP-1beta and fractalkine are also thought to be involved in the associated inflammatory response. There have been a number of studies in recent years investigating cytokine profiles in different forms of uveitis with a view to determining what cytokines are important in the inflamed eye. This review attempts to present the current state of knowledge from in vitro and in vivo research on the inflammatory cytokines in intraocular inflammatory diseases.

Vitrectomy for juvenile uveitis: prognostic factors for the long-term functional outcome

PURPOSE

This study evaluated the long-term effect of pars plana vitrectomy (PPV) in children and adolescents with chronic uveitis on visual function, anatomical outcome, and the requirement of systemic treatment. Further, predictive preoperative factors associated with a beneficial visual outcome were assessed.

METHODS

Retrospective review of 29 eyes of 23 consecutive paediatric and juvenile patients below 20 years of age with chronic uveitis who underwent a PPV for visually significant opacities in 25 eyes, vitreous haemorrhage in three eyes, and retinal detachment in one eye. The clinical diagnosis was chronic intermediate uveitis in 22 eyes and retinal vasculitis of different origin in seven eyes.

RESULTS

LogMAR visual acuity improved from an average of 0.91 to 0.33 (P<0.001). Cystoid macular oedema (CME) was significantly reduced in eight of 10 eyes postoperatively (P=0.021). In the multiple regression analysis, a low preoperative logMAR visual acuity and the presence of a CME had a negative influence on the final logMAR visual acuity. Furthermore, the appearance of chronic uveitis relapses was significantly reduced from 15 eyes before to seven eyes after surgery (P=0.042).

CONCLUSIONS

PPV has a beneficial effect on the course and the complications of chronic uveitis in paediatric and juvenile patients with respect to the anatomical and visual outcome. Preoperative logMAR visual acuity and clinically significant CME were the most accurate predictors for the functional outcome.

Is IL-10 a good target to inhibit choroidal neovascularisation in age-related macular disease?

Lightman discusses a new study that found that in a mouse model of choroidal neovascularisation (CNV), IL-10-deficient mice had decreased amounts of CNV.

The effect of pars plana vitrectomy on cystoid macular oedema associated with chronic uveitis: a randomised, controlled pilot study

AIM

To evaluate the efficacy of pars plana vitrectomy (PPV) in the management of chronic uveitic cystoid macular oedema (CMO).

METHODS

A prospective, interventional, randomised, controlled, pilot study. 23 eyes of 23 patients with CMO secondary to chronic intermediate or posterior uveitis unresponsive to medical treatment were randomised into a surgical (group S) or medical group (group M). 12 patients in group S underwent PPV as opposed to 11 patients in group M who received systemic corticosteroid and/or immunosuppressive treatment during the study period. The primary outcome measures of the study were change in visual acuity and angiographic appearance of CMO at 6 months.

RESULTS

Mean visual acuity in group S improved significantly from 1.0 (0.62) at baseline to 0.55 (0.29) at 6 months following vitrectomy (p = 0.011), with five (42%) eyes reaching vision of 20/40 or better. Conversely, mean visual acuity in group M improved only marginally by 0.03 (0.27) (p = 0.785). CMO after vitrectomy was angiographically improved in four (33%) eyes, remained unchanged in seven (58%) eyes, and deteriorated in one (8%) eye. In the medical group, fluorescein leakage decreased in one eye, did not alter in four eyes, and deteriorated in two eyes.

CONCLUSION

PPV for macular oedema secondary to chronic uveitis despite angiographic improvement in only one third of the patients, seems to have a significant beneficial effect on visual function. This study provides enough evidence to justify a large scale trial which would define the role of vitrectomy in uveitic macular oedema.

The development of complications in patients with chronic anterior uveitis

PURPOSE

This study aimed to identify the factors determining the ocular complications and visual outcome in patients with chronic anterior uveitis.

DESIGN

Retrospective, noncomparative case study.

METHODS

Ninety-one eyes of 68 patients with anterior uveitis that lasted longer than 3 months were assessed. Patients were divided into idiopathic and nonidiopathic chronic anterior uveitis and Fuchs' heterochromic uveitis. Visual acuity and complications such as posterior synechiae, cataract formation, raised intraocular pressure (IOP), and posterior segment complications (i.e., cystoid macular edema and optic nerve involvement) were evaluated. Poor visual outcome measured by life-table analysis was considered when logMAR (log of the reciprocal of Snellen visual acuity) visual acuity was 0.3 or worse.

RESULTS

No statistically significant differences in the visual outcome were found between the three groups of patients with chronic anterior uveitis. Posterior synechiae formation was, as expected, significantly increased in patients with chronic anterior uveitis compared with those with Fuchs' heterochromic uveitis. There was a trend for patients with nonidiopathic chronic anterior uveitis to have an increased risk of cystoid macular edema compared with those with idiopathic disease. There were no significant differences in visual outcome between any of the groups with time.

CONCLUSIONS

The visual prognosis for patients with chronic anterior uveitis is generally good. Posterior segment complications appear to be more likely to occur if there is an underlying associated disease. However, the presence of complications does not seem to affect the visual outcome in patients with chronic anterior uveitis.

Intracellular T lymphocyte cytokine profiles in the aqueous humour of patients with uveitis and correlation with clinical phenotype

This study aimed to investigate whether T cells in aqueous humour are different in different types of uveitis and correlate with clinical phenotype. Patients with clinically different types of uveitis, but all displaying active anterior uveitis, were phenotyped and samples of aqueous humour (AH) and peripheral blood (PB) collected. Cells from AH and PB were separated by centrifugation and by density gradient centrifugation (to obtain mononuclear cells PBMC), respectively. Cells were activated with PMA and ionomycin in the presence of Brefeldin A, stained for surface markers and intracellular cytokines, and analysed by flow cytometry. The cytokine profile was correlated with the clinical phenotype. Increased percentages of interleukin (IL)-10+-, but not interferon (IFN)-gamma+ T lymphocytes were found in AH compared with PB in patients with acute anterior uveitis (AAU), FHC or chronic panuveitis (PU). There was a trend towards elevated levels of IL-10+ T cells in AH from patients with FHC compared with AH from acute uveitis and panuveitis patients. Increased levels of IL-10+ T cells in AH compared with PB were also found in samples from patients with isolated uveitis, but not those with associated systemic disease. Levels of cytokine-positive T cells were not associated with the use of topical steroids or to the severity of the anterior uveitis. While type I cytokine-producing T lymphocytes are present in AH during AU, the presence of increased proportions of IL-10+ T lymphocytes in AH from patients with uveitis may be indicative of an anti-inflammatory mechanism that may influence the type and course of ocular inflammation in these patients.

Homing of mucosal lymphocytes to the liver in the pathogenesis of hepatic complications of inflammatory bowel disease

Primary sclerosing cholangitis is strongly linked to inflammatory bowel disease, but any model to explain the development of primary sclerosing cholangitis must take into account the fact that it usually runs a course independent from inflammation in the bowel, illustrated by the fact that this disease can develop many years after proctocolectomy. Thus, liver disease can develop in the absence of a diseased colon and cannot be explained solely by release of toxic factors from the inflamed gut. We propose the existence of an enterohepatic circulation of lymphocytes, whereby some mucosal lymphocytes generated in the gut during active inflammatory disease subsequently persist as longlived memory cells capable of recirculation through the liver. Under the right conditions, these dual-homing lymphocytes might become activated in the liver resulting in hepatic inflammation that is independent from inflammation in the gut. Recent reports that some lymphocyte homing-receptors are shared by the liver and gut provide a molecular basis for this hypothesis and explain the distribution of extraintestinal disease in inflammatory bowel disease.

The effect of pars plana vitrectomy in the management of Fuchs heterochromic cyclitis

PURPOSE

Fuchs heterochromic cyclitis (FHC) is characterized by a unilateral chronic iridocyclitis of insidious onset and uncertain cause. Our aim was to evaluate the effect of vitreous surgery in patients with FHC and clinically significant visual symptoms caused by inflammatory vitreous debris.

METHODS

This study was a review of 12 eyes of 12 consecutive patients with FHC who underwent pars plana vitrectomy for visually significant vitreous opacities. Cataract extraction with posterior chamber lens implantation had been performed on four eyes preoperatively. Four eyes had a concomitant lensectomy for cataracts, and one had a surgical posterior capsulotomy. Visual and anatomic data were recorded before surgery and for at least 6 months after surgery.

RESULTS

Visual acuity improved in all patients from an average logMAR of 0.57 to 0.007 (P = 0.0004) and by more than 2 Snellen lines in 8 of 12 of the eyes (P < 0.05). Symptoms of floaters resolved in all 11 patients in whom they were a symptom. Vitreous haze was cleared completely from an average Nussenblatt grade of 1.7 to 0 after 1 week (P = 0.0001).

CONCLUSIONS

Pars plana vitrectomy is a safe and effective treatment for the visual symptoms associated with FHC and can be combined safely with a lensectomy if required.

Pars plana vitrectomy for cystoid macular edema secondary to sarcoid uveitis

OBJECTIVE

To examine the results of pars plana vitrectomy for cystoid macular edema secondary to sarcoid uveitis resistant to medical treatment.

DESIGN

Retrospective, interventional, noncomparative case series.

SUBJECTS

Fourteen consecutive subjects (18 eyes) with cystoid macular edema associated with sarcoid uveitis resistant to medical treatment.

INTERVENTION

All eyes underwent pars plana vitrectomy. Nine eyes also underwent peeling of the epiretinal membrane or removal of the posterior vitreous cortex.

MAIN OUTCOME MEASURES

Status of macular edema, visual acuity, and complications.

RESULTS

Ten eyes (56%) improved 2 or more lines of Snellen visual acuity within 12 months. Six eyes (33%) remained unchanged, within a line of preoperative Snellen visual acuity, and two eyes (11%) worsened by 2 or more lines of Snellen visual acuity. Slit-lamp biomicroscopy showed that cystoid macular edema had resolved in 14 eyes (78%) within 9 months postoperatively. One eye (6%) had minimal edema, whereas three eyes (17%) remained unchanged biomicroscopically at the final visit. Postoperative complications included cataract formation, glaucoma, optic nerve atrophy, epiretinal membrane formation, and tractional retinal detachment. No severe postoperative inflammation was noted.

CONCLUSIONS

Pars plana vitrectomy seems to have a beneficial effect on cystoid macular edema caused by sarcoidosis resistant to medical treatment.

Keratoconus and Fuchs' heterochromic iridocyclitis: a coincidence or a defect during embryogenesis?

PURPOSE

We aimed to discuss the possible role of developmental embryologic factors in neural crest cells in the aetiology of keratoconus and Fuchs' heterochromic iridocyclitis by presenting this case.

CASE REPORT

We diagnosed bilateral keratoconus and unilateral Fuchs' heterochromic iridocyclitis in a 19 year old women complaining of progressively blurring vision in her left eye. We also examined most of her first and second degree relatives. One niece had FHI in addition to a choroidal nevus in the inferior temporal quadrant of her left eye.

DISCUSSION

Regarding the common embryological origins of iris stroma, uveal melanocytes and corneal stroma, it might be worth considering that the combination of FHI and keratoconus is not coincidental. A role of embryologic factors in neural crest cells in the etiology of both diseases cannot be excluded.