SGLT2 inhibitors and diabetic retinopathy progression.

PURPOSE: To evaluate whether sodium-glucose co-transporter 2 (SGLT2) inhibitors affect progression of non-proliferative diabetic retinopathy (NPDR) compared to standard of care. METHODS: A retrospective cohort study compared subjects enrolled in a commercial and Medicare Advantage medical claims database who filled a prescription for a SGLT2 inhibitor between 2013 and 2020 to unexposed controls, matched up to a 1:3 ratio. Patients were excluded if they were enrolled for less than 2 years in the plan, had no prior ophthalmologic exam, had no diagnosis of NPDR, had a diagnosis of diabetic macular edema (DME) or proliferative diabetic retinopathy (PDR), had received treatment for vision-threatening diabetic retinopathy (VTDR), or were younger than 18 years. To balance covariates of interest between the cohorts, an inverse probability treatment weighting (IPTW) propensity score for SGLT2 inhibitor exposure was used. Multivariate Cox proportional hazard regression modeling was employed to assess the hazard ratio (HR) for VTDR, PDR, or DME relative to SGLT2 exposure. RESULTS: A total of 6065 patients who initiated an SGLT2 inhibitor were matched to 12,890 controls. There were 734 (12%), 657 (10.8%), and 72 (1.18%) cases of VTDR, DME, and PDR, respectively, in the SGLT2 inhibitor cohort. Conversely, there were 1479 (11.4%), 1331 (10.3%), and 128 (0.99%) cases of VTDR, DME, and PDR, respectively, among controls. After IPTW, Cox regression analysis showed no difference in hazard for VTDR, PDR, or DME in the SGLT2 inhibitor-exposed cohort relative to the unexposed group [HR = 1.04, 95% CI 0.94 to 1.15 for VTDR; HR = 1.03, 95% CI 0.93 to 1.14 for DME; HR = 1.22, 95% CI 0.89 to 1.67 for PDR]. CONCLUSION: Exposure to SGLT2 inhibitor therapy was not associated with progression of NPDR compared to patients receiving other diabetic therapies.

A large meta-analysis identifies genes associated with anterior uveitis.

Anterior Uveitis (AU) is the inflammation of the anterior part of the eye, the iris and ciliary body and is strongly associated with HLA-B*27. We report AU exome sequencing results from eight independent cohorts consisting of 3,850 cases and 916,549 controls. We identify common genome-wide significant loci in HLA-B (OR = 3.37, p = 1.03e-196) and ERAP1 (OR = 0.86, p = 1.1e-08), and find IPMK (OR = 9.4, p = 4.42e-09) and IDO2 (OR = 3.61, p = 6.16e-08) as genome-wide significant genes based on the burden of rare coding variants. Dividing the cohort into HLA-B*27 positive and negative individuals, we find ERAP1 haplotype is strongly protective only for B*27-positive AU (OR = 0.73, p = 5.2e-10). Investigation of B*27-negative AU identifies a common signal near HLA-DPB1 (rs3117230, OR = 1.26, p = 2.7e-08), risk genes IPMK and IDO2, and several additional candidate risk genes, including ADGFR5, STXBP2, and ACHE. Taken together, we decipher the genetics underlying B*27-positive and -negative AU and identify rare and common genetic signals for both subtypes of disease.

OUTER RETINOPATHY AND MICROANGIOPATHY IN ACUTE MYELOGENOUS LEUKEMIA.

PURPOSE: To describe a patient with acute myelogenous leukemia who presented with a recurrent, bilateral, outer retinopathy, before and after consolidative peripheral blood stem cell transplantation complicated by chronic graft-versus-host disease. METHODS: This is a retrospective review of records from a 23-year-old woman with acute myelogenous leukemia who underwent comprehensive ophthalmic evaluations for over a year including chromatic perimetry and multifocal electroretinograms, imaging with spectral domain optical coherence tomography, near-infrared and short-wavelength fundus reflectance and autofluorescence, fluorescein and optical coherence tomography angiography. RESULTS: The patient presented with recurrent, unilateral paracentral scotomas. There was localized loss of inner segment ellipsoid (EZ) and photoreceptor outer segment signals (IZ) in the pericentral retina of both eyes co-localizing with hyperreflective lesions on near-infrared reflectance. She subsequently lost vision (visual acuity = 20/200) in the right eye a year after consolidative peripheral blood stem cell transplantation complicated by steroid-resistant-chronic graft-versus-host disease. There was loss of the EZ and IZ signals corresponding to a dense central cone scotoma and multifocal electroretinograms depression. Near-infrared autofluorescence, fluorescein and optical coherence tomography angiography were within normal limits. Visual acuity (20/20) and retinal sensitivities improved with restoration of the EZ/IZ signals after oral prednisone and intravenous rituximab, but left a residual photoreceptor loss and paracentral scotoma. CONCLUSION: We propose that an immune-mediated microangiopathy may explain the protracted, recurrent course of primary photoreceptor abnormalities in our patient, which was further complicated by manifestations of chronic graft-versus-host disease following consolidative peripheral blood stem cell transplantation. Outer retinal findings previously documented in leukemia may be explained by a similar mechanism.

Vitreoretinal lymphoma presenting as frosted branch angiitis in a patient with diffuse large B-cell lymphoma.

Purpose: To describe the evaluation, diagnosis, and treatment of vitreoretinal lymphoma presenting as frosted branch angiitis in a patient with diffuse large B-cell lymphoma (DLBCL). Observations: A 57-year-old woman with a history of non-Hodgkin lymphoma and recent DLBCL relapse presented with frosted branch angiitis that raised suspicion for an infectious retinitis but was found to be vitreoretinal lymphoma. Conclusions and Importance: This case primarily highlights the importance of considering vitreoretinal lymphoma on the differential diagnosis of etiologies of frosted branch angiitis. Despite suspicion for vitreoretinal lymphoma, it is also important to treat empirically for infectious etiologies of retinitis in cases of frosted branch angiitis. In this case where the diagnosis was ultimately vitreoretinal lymphoma, weekly alternating intravitreal injections of methotrexate and rituximab led to improvement in visual acuity and retinal infiltration.

OPHTHALMIC ARTERY OCCLUSION AS THE PRESENTING SIGN OF ACQUIRED IMMUNODEFICIENCY SYNDROME.

BACKGROUND/PURPOSE: The purpose of this study was to describe a case of severe occlusive vasculitis that led to a diagnosis of AIDS in a previously healthy middle-aged man. METHODS: Multimodal imaging including widefield fundus photography, spectral domain optical coherence tomography, and widefield fluorescein angiography was performed. RESULTS: A healthy 46-year-old man presented with sudden onset vision loss in his left eye with an afferent pupillary defect. His examination revealed signs of retinal vascular disease in both eyes, with an ophthalmic artery occlusion in his affected left eye and a hemiretinal vein occlusion in his asymptomatic right eye. An extensive medical workup was significant for HIV positivity; he was ultimately diagnosed with AIDS, and ocular findings were attributed to an associated occlusive vasculitis. He developed anterior segment neovascularization in the left eye for which he received intravitreal bevacizumab and panretinal photocoagulation. He ultimately required cyclophotocoagulation in the left eye for poorly controlled intraocular pressure in the setting of neovascular glaucoma. CONCLUSION: Although HIV is most classically associated with a retinal microangiopathy, testing should be considered in cases of occlusive retinal vasculitis because it is a rare cause of such findings.

UTILITY OF OCULAR ß- d -GLUCAN TESTING IN PATIENTS WITH FUNGAL ENDOPHTHALMITIS.

PURPOSE: To assess the diagnostic utility of (1→3)-ß- d -glucan (BDG) in ocular fluid of patients with fungal endophthalmitis. METHODS: This prospective pilot single-center study evaluated aqueous and vitreous humor BDG levels of suspected fungal endophthalmitis, bacterial endophthalmitis, and noninfectious controls with the standard Fungitell assay and the Fungitell STAT assay. ß- d -Glucan levels were compared using generalized linear models followed by post hoc pairwise comparisons. RESULTS: Seven fungal endophthalmitis, 6 bacterial endophthalmitis, and 17 noninfectious ocular samples were evaluated. Mean aqueous BDG concentrations were 204, 11.0, and 9.6 pg/mL for fungal endophthalmitis, bacterial endophthalmitis, and noninfectious controls, respectively ( P = 0.01, fungal vs. bacterial; P = 0.0005, fungal vs. noninfectious controls). Mean vitreous BDG concentrations were 165, 30.3, and 5.4 pg/mL, respectively ( P = 0.001 for fungal vs. bacterial; P < 0.0001 for fungal vs. noninfectious controls). Mean vitreous BDG index (Fungitell STAT) values were 1.7, 0.4, and 0.3, respectively ( P = 0.001, fungal vs. bacterial; P = 0.0004, fungal vs. noninfectious controls). The Pearson correlation between BDG levels and BDG index was high (correlation coefficient = 0.99, P < 0.001). CONCLUSION: Significantly elevated ocular BDG levels were found in fungal endophthalmitis compared with bacterial endophthalmitis and noninfectious controls. Our study suggests a potential utility for BDG testing in the diagnosis of fungal endophthalmitis, and a larger study is warranted.

Implications of fibrotic extracellular matrix in diabetic retinopathy.

Fibrosis is an accumulation of extracellular matrix (ECM) proteins and fibers in a disordered fashion, which compromises cell and tissue functions. High glucose-induced fibrosis, a major pathophysiological change of diabetic retinopathy (DR), severely affects vision by compromising the retinal vasculature and ultimately disrupting retinal tissue organization. The retina is a highly vascularized, stratified tissue with multiple cell types organized into distinct layers. Chronically high blood glucose stimulates certain retinal cells to increase production and assembly of ECM proteins resulting in excess ECM deposition primarily in the capillary walls on the basal side of the endothelium. This subendothelial fibrosis of the capillaries is the earliest histological change in the diabetic retina and has been linked to the vascular dysfunction that underlies DR. Proteins that are not normally abundant in the capillary basement membrane (BM) matrix, such as the ECM protein fibronectin, are assembled in significant quantities, disrupting the architecture of the BM and altering its properties. Cell culture models have identified multiple mechanisms through which elevated glucose can stimulate fibronectin matrix assembly, including intracellular signaling pathways, alternative splicing, and non-enzymatic glycation of the ECM. The fibrotic subendothelial matrix alters cell adhesion and supports further accumulation of other ECM proteins leading to disruption of endothelial cell-cell junctions. We review evidence supporting the notion that these molecular changes in the ECM contribute to the pathogenesis of DR, including vascular leakage, loss of endothelial cells and pericytes, changes in blood flow, and neovascularization. We propose that the accumulation of ECM, especially fibronectin matrix, first around the vasculature and later in extravascular locations, plays a critical role in DR and vision loss. Strategies for DR prevention and treatment should consider the ECM a potential therapeutic target.

A NOVEL APPROACH TO SCLERAL FIXATION OF POSTERIOR CHAMBER INTRAOCULAR LENSES AND CAPSULAR TENSION RINGS AND SEGMENTS IN DEEP-SET EYES.

PURPOSE: To demonstrate a novel approach to scleral fixation of posterior chamber intraocular lenses and capsular tension rings and segments in deep-set eyes using the Finesse FlexLoop (Alcon Laboratories). METHODS: The technique described herein, based on previous approaches to scleral fixation of posterior chamber intraocular lenses, uniquely employs the FlexLoop to "lasso" Gore-Tex sutures that have already been threaded through the eyelets of a CZ70BD (Alcon Laboratories) IOL and externalize them. RESULTS: All patients who underwent surgery with this technique experienced visual improvement. The only complication was of mild hyphema in the patient who had a capsular tension segment placed, which resolved with medical therapy. CONCLUSION: The advantages of this procedure include a smaller diameter instrument (FlexLoop) as compared to the 25-gauge forceps typically employed, an easier to perform surgical maneuver that alleviates the need for both precise placement and constant tension to be exerted by the surgeon to grasp the sutures, as well as an instrument that can function when bent up to 45° to help accommodate deep-set eyes requiring this procedure.

Efficacy of Maribavir in Valganciclovir-Resistant Cytomegalovirus Retinitis.

PURPOSE: To determine whether maribavir is effective at treating ganciclovir-resistant cytomegalovirus retinitis. METHODS: Retrospective case report of a lung transplant patient with bilateral cytomegalovirus retinitis documented with serum and aqueous humor studies and color fundus photographs. RESULTS: A 72-year-old lung transplant patient with active ganciclovir-resistant cytomegalovirus was treated with intravitreal foscarnet therapy in one eye. Retinitis developed in the contralateral eye and was managed with systemic maribavir alone. Active retinitis regressed in both the eye treated with intravitreal foscarnet and the un-injected eye. CONCLUSIONS: This patient's results suggest that systemic maribavir is an effective treatment for treatment-resistant cytomegalovirus retinitis.

Central Retinal Vein Occlusion in a 46-Year-Old Man with COVID-19: Case Report and Review of the Literature.

A 46-year-old man with a history of well-controlled hypertension presented with a central retinal vein occlusion (CRVO) in his right eye, which was complicated by cystoid macular edema. When the patient noted new visual symptoms, he was also experiencing muscle aches and easy fatiguability. A standard hypercoagulability panel failed to identify an etiology for his CRVO. However, the patient underwent COVID-19 antibody testing, which returned positive. The patient received a series of aflibercept injections for his macular edema, and his vision improved. Further study is warranted to determine if there is any association between mild infection with COVID-19 and the development of CRVO.

The Proteome of Preretinal Tissue in Proliferative Vitreoretinopathy.

BACKGROUND AND OBJECTIVE: Proliferative vitreoretinopathy (PVR) is the leading cause of retinal detachment repair failure. However, the molecular pathogenesis remains incompletely understood. Determining the proteome of PVR will help to identify novel therapeutic targets. MATERIALS AND METHODS: Preretinal tissue samples, delaminated during surgery from six PVR cases and one idiopathic epiretinal membrane (ERM) were analyzed by mass spectrometry. Tandem mass spectra were extracted using the UniProt database, generating a list of 896 proteins, which were subjected to pathway set and fold-change (ERM vs PVR) analyses. RESULTS: Two pathways were enriched in PVR: extracellular matrix (ECM) organization and extracellular structure organization. A fold-change analysis comparing mean total spectral counts from PVR to an ERM control identified fibronectin, the ECM glycoprotein, as the protein most significantly elevated in PVR compared to ERM. CONCLUSION: These data identify pathwayskey to PVR progression, including thoseinvolved in cell-mediated ECM assembly and thus tractional force generation at the cellular level. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:S5-S12.].

Minireview: Fibronectin in retinal disease.

Retinal fibrosis, characterized by dysregulation of extracellular matrix (ECM) protein deposition by retinal endothelial cells, pigment epithelial cells, and other resident cell-types, is a unifying feature of several common retinal diseases. Fibronectin is an early constituent of newly deposited ECM and serves as a template for assembly of other ECM proteins, including collagens. Under physiologic conditions, fibronectin is found in all layers of Bruch's membrane. Proliferative vitreoretinopathy (PVR), a complication of retinal surgery, is characterized by ECM accumulation. Among the earliest histologic manifestations of diabetic retinopathy (DR) is capillary basement membrane thickening, which occurs due to perturbations in ECM homeostasis. Neovascularization, the hallmark of late stage DR as well as exudative age-related macular degeneration (AMD), involves ECM assembly as a scaffold for the aberrant new vessel architecture. Rodent models of retinal injury demonstrate a key role for fibronectin in complications characteristic of PVR, including retinal detachment. In mouse models of DR, reducing fibronectin gene expression has been shown to arrest the accumulation of ECM in the capillary basement membrane. Alterations in matrix metalloproteinase activity thought to be important in the pathogenesis of AMD impact the turnover of fibronectin matrix as well as collagens. Growth factors involved in PVR, AMD, and DR, such as PDGF and TGFß, are known to stimulate fibronectin matrix assembly. A deeper understanding of how pathologic ECM deposition contributes to disease progression may help to identify novel targets for therapeutic intervention.

Retina Specialists Treating Diabetic Macular Edema Recommend Different Approaches for Patients Than They Would Choose for Themselves.

BACKGROUND AND OBJECTIVE: Prior investigation shows retina specialists may select different treatment for age-related macular degeneration for themselves than for a hypothetical patient. The authors sought to investigate whether a similar bias exists for treatment decisions by retina specialists with regard to diabetic macular edema (DME). PATIENTS AND METHODS: Two surveys asked retina specialists to select treatment for hypothetical patients with DME or for themselves. In Survey 2, a distinction was drawn between a visual acuity (VA) of 20/40 or better and 20/50 or worse. RESULTS: In Survey 1, 54% to 61% of respondents selected bevacizumab (Avastin; Genentech, South San Francisco, CA) for patients and 36% to 40% selected the drug for themselves (P < .0004). It was found that 14% to 17% selected aflibercept (Eylea; Regeneron, Tarrytown, NY) for patients versus 31% to 38% who selected it for themselves (P < .0001). For a VA of 20/40 or better, 42% to 50% selected bevacizumab for their patients versus 32% to 39% (P < .0005) for themselves, and 20% to 23% selected aflibercept for patients versus 39% to 48% (P < .0007) for themselves. For a VA of 20/50 or worse, 24% to 28% chose bevacizumab for patients versus 17% to 20% for themselves (P value was not significant), and 59% to 66% selected aflibercept for their patients versus 66% to 78% for themselves (P < .05). CONCLUSION: Physicians recommend different treatment for their patients than for themselves, though not for a VA of 20/50 or worse, where data support the use of aflibercept over bevacizumab. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:544-554.].

ONE-YEAR OUTCOMES OF A NOVEL TECHNIQUE FOR RESCUING AND SCLERAL FIXATING A POSTERIOR DISLOCATED INTRAOCULAR LENS-BAG COMPLEX WITHOUT CONJUNCTIVAL OPENING (HOFFMAN POCKETS).

PURPOSE: To present the 1-year follow-up of a novel surgical technique that allows for suture fixation of a posteriorly dislocated lens-bag complex without the need for conjunctival incision. METHODS: A retrospective chart review of 19 patients who underwent posterior chamber intraocular lens rescue using the novel surgical technique was performed. Data were collected 1 year after surgery for all patients. RESULTS: Average preoperative vision was 20/500, whereas 3 months and 12 months postoperatively, the vision was 20/65 and 20/54, respectively. Three of 15 eyes had decentration of the sutured intraocular lens, 2 of which required additional surgical repair. CONCLUSION: Outcome data at 1 year support this novel technique as a viable option for the surgical repair of a dislocated lens-capsular bag complex.

Effects of high glucose on integrin activity and fibronectin matrix assembly by mesangial cells.

The filtration unit of the kidney is the glomerulus, a capillary network supported by mesangial cells and extracellular matrix (ECM). Glomerular function is compromised in diabetic nephropathy (DN) by uncontrolled buildup of ECM, especially type IV collagen, which progressively occludes the capillaries. Increased levels of the ECM protein fibronectin (FN) are also present; however, its role in DN is unknown. Mesangial cells cultured under high glucose conditions provide a model system for studying the effect of elevated glucose on deposition of FN and collagen IV. Imaging of mesangial cell cultures and analysis of detergent-insoluble matrix show that, under high glucose conditions, mesangial cells assembled significantly more FN matrix, independent of FN protein levels. High glucose conditions induced protein kinase C-dependent ß1 integrin activation, and FN assembly in normal glucose was increased by stimulation of integrin activity with Mn(2+). Collagen IV incorporation into the matrix was also increased under high glucose conditions and colocalized with FN fibrils. An inhibitor of FN matrix assembly prevented collagen IV deposition, demonstrating dependence of collagen IV on FN matrix. We conclude that high glucose induces FN assembly, which contributes to collagen IV accumulation. Enhanced assembly of FN might facilitate dysregulated ECM accumulation in DN.