Ocular mucous membrane pemphigoid: a review

Childhood-onset ocular mucous membrane pemphigoid presenting with peripheral ulcerative keratitis: a case report and review of the literature

PURPOSE

The purpose of this study was to describe the case of a pediatric patient diagnosed with mucous membrane pemphigoid (MMP) with exclusive ocular involvement presenting at diagnosis with peripheral ulcerative keratitis and provide a review of the literature.

METHODS

A 12-year-old girl presented with cicatricial conjunctivitis and peripheral ulcerative keratitis (PUK). A conjunctival biopsy and direct immunofluorescence revealed linear deposits of IgG, IgM, and C3 at the basement membrane zone, confirming a diagnosis of ocular MMP.

RESULTS

The patient was initially treated with dapsone 25 mg/day and prednisone 40 mg/day along with topical treatment including cyclosporine 0.05%, loteprednol etabonate 0.05%, and sodium hyaluronate 0.15% and trehalose 3%. Inflammation persisted as an increase in the extension of symblepharon was documented. Subsequently, dapsone was switched to oral methotrexate 15 mg/week and prednisone was successfully tapered to 5 mg/day. After three years of follow-up, disease activity remained quiescent.

CONCLUSIONS

Pediatric mucous membrane pemphigoid with ocular involvement is a rare condition of which few reports have been published, resulting in scarce information regarding its clinical course and response to treatment. We report the first case observed in a Hispanic patient, opening with peripheral ulcerative keratitis, and responding successfully to methotrexate.

Tear Protein Biomarkers for Ocular Mucous Membrane Pemphigoid Uncovered Using Targeted LC-MS/MS

Mucous membrane pemphigoid (MMP) is a multisystemic rare autoimmune disease affecting the skin and mucous membranes. Ocular involvement is characterized by chronic conjunctival inflammation causing scar formation, leading to corneal opacification and vision loss. Conjunctival biopsies are currently used to confirm diagnosis, and the associated immunosuppression treatments prescribed can have serious consequences on patients. To address these challenges, a noninvasive approach to collect patient tears using untargeted and targeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses has been developed to identify a list of potential biomarkers of ocular MMP. Samples were collected on Schirmer strips and subjected to tryptic digestion and LC-MS/MS analysis. Three cohorts of patients were studied, and targeted LC-scheduled multiple reaction monitoring (LC-sMRM) methods were developed for the verification of putative biomarkers. The comparison of three groups of patients, those diagnosed with ocular MMP, non-ocular MMP, and lichen planus, another ocular cicatricial conjunctivitis disorder, yielded 56 biomarkers of interest. Proteins distinguishing MMP patients with and without ocular involvement were linked to the extracellular matrix, metabolism, and neutrophil degranulation. The comparison between MMP and lichen planus patients highlighted lower levels of metabolic enzymes in the latter. This study highlights the use of multiple patient cohorts and tailored targeted quantitative proteomics methods for the discovery of biomarkers for diagnostic and prognostic purposes.

Incidence and Outcomes of Cataract in Eyes with Ocular Cicatricial Pemphigoid

PURPOSE

To identify the incidence of cataract and the outcomes of cataract surgery in eyes with ocular cicatricial pemphigoid (OCP).

METHODS

Phakic eyes were identified from the Systemic Immunosuppressive Therapy for Eye Diseases Cohort Study and followed for the incidence of visually significant cataract defined as: newly reduced visual acuity 20/50 or worse attributed to cataract; and/or incident cataract surgery. Secondarily, all eyes with OCP that underwent cataract surgery and had a year of follow up thereafter, were included in an analysis of visual outcome.

RESULTS

Three hundred fifty-five phakic eyes (200 patients) with OCP were at risk. Eighty eyes developed visually significant cataract over 1064 eye years (incidence rate = 7.5%/eye-year, 95% confidence interval [CI] = 5.6 to 10.1). Higher age was associated with increased incidence of cataract (adjusted hazard ratio [aHR] = 4.47; 95% CI, 1.95-10.23 for age 60-75 inclusive and aHR = 8.37; 95% CI, 3.60-19.42 for age > 75, each compared with age <60 years). Seventy-nine eyes of 61 patients were monitored for > = 1 year following cataract surgery. Cataract surgery was associated with an improvement of vision around 4 lines, which was sustained through at least 48 months. Poorer pre-operative visual acuity was associated with poorer long-term visual outcome.

CONCLUSIONS

The incidence of cataract was high in this older population. No factors predictive of cataract such as duration of OCP or use of corticosteroids were identified. Visual acuity improved after surgery by a median of 4 lines' gain at one year; poorer long-term outcome among those with initially poorer visual acuity may be secondary to corneal scarring.

Challenging corneal diseases and microRNA expression: Focus on rare diseases and new therapeutic frontiers

MicroRNAs (miRNAs) function as posttranscriptional regulators of gene expression by targeting specific messenger RNA (mRNA). This interaction modulates mRNA stability or translational efficiency, ultimately impacting the level of protein production. Emerging evidence suggests that miRNAs act as critical regulators in corneal diseases. These molecules finetune key processes like cell proliferation, differentiation, inflammation, and wound healing. We reviewed the literature to understand the role that miRNAs may play in the development of challenging and poorly understood corneal diseases. We focused on vernal keratoconjunctivitis, neurotrophic keratitis, keratoconus, Fuchs endothelial corneal dystrophy, and limbal stem cell deficiency. Furthermore, we explored currently studied agonists or antagonists of miRNAs that share similar pathways with ocular diseases and could be employed in ophthalmology in the future. The distinct miRNA expression profiles observed in different ocular surface pathologies, combined with the remarkable stability and relatively easy access of miRNA sampling in biofluids, present possibilities for the development of noninvasive and highly accurate diagnostic tools. Furthermore, comprehending miRNA's pathophysiological role could open new frontiers to a more comprehensive understanding of the pathophysiology underlying ocular surface diseases, thereby paving the way for the creation of novel therapeutic strategies.

Clinical Characteristics of Ocular Mucous Membrane Pemphigoid: A Systematic Review and Meta-Analysis

PURPOSE

To synthesize the evidence and generate a combined weighted measure on the frequency of ocular manifestations of mucous membrane pemphigoid (OMMP).

METHODS

Systematic literature review and meta-analysis, searching PubMed, Embase, VHL, and Google Scholar. Articles reporting patients with mucous membrane pemphigoid and ocular involvement were included. At least, two reviewers independently and in parallel participated in all the following phases; preliminary screening, full-text review, risk of bias assessment by validated tools, and data extraction. Qualitative analysis and meta-analysis were conducted. This study was previously registered in PROSPERO (CRD42023451844).

RESULTS

Thirty-five studies met the inclusion criteria, comprising 1,439 patients and 1,040 eyes summarized in qualitative analysis. Twenty-eight studies were included in the meta-analysis. Ages included ranged from 60.4 to 75 years. Women were reported with more frequency. The mean time for diagnosis was 55.1 months, usually with bilateral ocular disease in 90% (95% CI 78%; 96%). Trichiasis and entropion were the most frequent manifestations in up to 92%, followed by symblepharon and punctate keratitis. Ankyloblepharon, persistent epithelial defects, and visual impairment were less frequent complications. Direct immunofluorescence positivity in conjunctival biopsies was 54% (95% CI 43%; 64%). Extraocular involvement was highly frequent, being oral and skin involvement the most frequently reported.

CONCLUSIONS

Our systematic review and meta-analysis evidenced that patients around 60 years of age are the most affected population with a female preponderance, usually with bilateral ocular involvement. Trichiasis and entropion were the most frequent findings; although visual impairment and persistent epithelial defects were less reported, they should not be overlooked in suspected OMMP.

The Role of Serology in the Diagnosis of Ocular Predominant Mucous Membrane Pemphigoid and the Search for an Ocular-Specific Autoantigen

Ocular predominant mucous membrane pemphigoid (oMMP) is a severe subtype of MMP that can lead to scarring and blindness. While conjunctival biopsy for direct immunofluorescence (DIF) is considered the gold standard for diagnosis, limited sensitivity results in a false-negative rate upwards of 40%. Likewise, it remains unclear to what extent a negative biopsy, whether false-negative or true-negative, results in a different prognosis, with patients previously termed "pseudopemphigoid" demonstrating comparable disease progression. Serologic testing allows for a less invasive means to demonstrate circulating autoantibodies against known autoantigens in pemphigoid diseases. Patients with MMP, particularly oMMP, however, typically demonstrate low titers of circulating autoantibodies, limiting the diagnostic utility of these tests. The autoantigen integrin β4 has been previously reported to be a specific marker of pure ocular MMP, while in the majority of patients with oMMP, the identified target antigens are BP180 (type XVII collagen) and laminin 332. Recent studies have, however, demonstrated inconsistent reactivity and specificity for integrin β4 as an ocular-specific marker in MMP. Herein, we review the role of serologic testing in the diagnosis and prognosis of oMMP, as well as the current understanding of autoantigens in oMMP.Abbreviations: BMZ - basement membrane zone, DIF - direct immunofluorescence, IIF - indirect immunofluorescence, MMP - mucous membrane pemphigoid, oMMP - ocular predominant mucous membrane pemphigoid.

Clinical and demographic characteristics of mucous membrane pemphigoid in India: A retrospective analysis

Background Mucous membrane pemphigoid (MMP) is a rare subepidermal autoimmune blistering disorder. The clinical and demographic parameters of this disease in Indian patients have not yet been elucidated in detail. Objective We aimed to study the clinical and demographic characteristics, disease course, and treatment aspects of MMP patients. Methods The data for this study were obtained by reviewing the case record forms of patients registered in the Autoimmune Bullous Disease (AIBD) Clinic of the Department of Dermatology, Venereology & Leprology, Postgraduate Institute of Medical Education and Research, Chandigarh, a tertiary care centre in India. The diagnosis of MMP was established on the basis of clinical and immune-histopathological features which are consistent with standard diagnostic criteria for the disease. Results A total of 52 patients with MMP registered in the AIBD clinic were included. The mean age at disease onset was 50 years and the average age at presentation was 56 years. Females outnumbered males in the study with a ratio of 1.36:1. The oral and ocular mucosae were the most commonly affected sites (82.6% and 63.4% respectively). Visual difficulty was reported by half the patients (26 of 52 patients). IgG, C3, and IgA deposits were detected on direct immunofluorescence (DIF) in 29, 21, and 11 patients, respectively. Serologic analysis was performed in only 7 of the patients and of these, just 1 exhibited a positive result on multivariant ELISA and epidermal pattern of binding on salt split skin indirect immunofluorescence. Most patients were treated with prednisolone (44 of 52). Steroid-sparing adjuvants were used in combination including cyclophosphamide, azathioprine, methotrexate, dapsone, and colchicine. Rituximab was administered in 7 patients with severe or refractory disease. Limitations This is a retrospective analysis of data available from a clinic registry. In patients with negative direct immunofluorescence on biopsy, the diagnosis was based on clinico-pathologic consensus. Conclusion MMP is not as uncommon in India as the paucity of reports suggest. Visual complications are frequent in Indian MMP patients. A high index of suspicion is required for early diagnosis and appropriate treatment to prevent ocular complications.

Ocular cicatricial pemphigoid: is there an association with autoimmune diseases?

PURPOSE

To assess the prevalence of autoimmune diseases (ADs) associated with ocular cicatricial pemphigoid (OCP) and analyze clinical, laboratory, and treatment associations between these entities.

METHODS

A multicentre cross-sectional study of patients with an OCP diagnosis. The population was divided into two groups according to their association with other ADs or not. Clinical, laboratory and treatment variables were described and compared between groups. A multivariable logistic regression analysis was performed to identify variables that could suggest the association between OCP and ADs.

RESULTS

Eighty-eight patients were recruited, with a mean age at diagnosis of 64.3 years (SD 11.9). Biopsy was performed in 86.8% of the patients. There was a median delay of 2 years from the onset of symptoms to diagnosis. Extraocular involvement was evidenced in 11.5%. The group associated with ADs included 24 patients (27.3%). The most prevalent diagnosis was Sjögren´s syndrome. Hypergammaglobulinemia was associated with ADs and OCP, adjusted for age, sex, smoking, skin and mucosal involvement, and erythrocyte sedimentation rate (OR 8.7; 95%CI 1.6-46.8; p = 0.012).

CONCLUSIONS

Due to OCP's autoimmune nature, it could coexist with other ADs. This study observed that more than a quarter of the population presented with this association, and hypergammaglobulinemia could suggest it.

Diagnostic and prognostic values of conjunctival and oral biopsies analyzed by direct immunofluorescence in patients with mucous membrane pemphigoid

Introduction

Mucous membrane pemphigoid (MMP) is diagnosed on the basis of a characteristic clinical picture (a predilection for mucosal involvement and scarring in the affected tissues) and a positive direct immunofluorescence (DIF) result.

Methods

In this study, we compare the diagnostic and prognostic values of conjunctival and oral biopsies analyzed by DIF in patients with MMP. Sixteen patients with MMP and mucosal involvement as a predominant symptom were classified into three groups based on the clinical picture. Oral and conjunctival DIF were performed on all patients.

Results

Our study showed that patients with simultaneous oral and conjunctival involvement had a positive oral DIF in 83% and a positive ocular DIF in 100% of the examined cases, respectively. Patients with isolated ocular MMP had a positive oral DIF in 50% and a positive ocular DIF in 66% of the examined cases, respectively. Patients with only oral involvement with MMP had a positive oral DIF in 100% and a positive ocular DIF in 50% of the examined cases, respectively.

Discussion

Oral biopsy should be performed first and is usually sufficient for the diagnosis, even in patients with exclusively ocular MMP, whereas in patients without clinical ocular involvement, ocular DIF is positive in half of the cases and may be a predictive factor for ocular lesions in the future.

Ocular involvement in autoimmune bullous diseases

Autoimmune bullous diseases represent a heterogenous group of disorders caused by autoantibodies against adhesion molecules; the location of the target protein determines the level of cleft formation. The spectrum of ocular lesions in autoimmune bullous diseases can range from mild symptoms to severe involvement with sight impairment and even, in some cases, blindness. In pemphigus vulgaris, the prevalence of ocular involvement has been reported to be between 7% and 26%. The most common clinical sign of ocular pemphigus vulgaris is bilateral conjunctivitis with hyperemia. Ocular involvement also occurs in 41% to 70% of patients with paraneoplastic pemphigus. The main ocular manifestations are bilateral cicatrizing conjunctivitis with symblepharon formation, and shortening of the fornices. In mucous membrane pemphigoid, ocular involvement is seen in 61% to 70% of patients; the most frequent ocular finding is cicatricial conjunctivitis. Patients with autoimmune bullous diseases having common ocular involvement should be assessed by an ophthalmologist to avoid serious complications. Diagnostic procedures and treatment require multidisciplinary care based on the close cooperation between dermatologists and ophthalmologists.

The Multifold Etiologies of Limbal Stem Cell Deficiency: A Comprehensive Review on the Etiologies and Additional Treatment Options for Limbal Stem Cell Deficiency

Given the various ocular manifestations of limbal stem cell insufficiency, an awareness of the genetic, acquired, and immunological causes and associated additional treatments of limbal stem cell deficiency (LSCD) is essential for providers. We performed a comprehensive review of the literature on the various etiologies and specific therapies for LSCD. The resources utilized in this review included Medline (PubMed), Embase, and Google Scholar. All English-language articles and case reports published from November 1986 through to October 2022 were reviewed in this study. There were collectively 99 articles on these topics. No other exclusion criteria were applied. Depending on the etiology, ocular manifestations of limbal stem cell deficiency range from dry eye syndrome and redness to more severe outcomes, including corneal ulceration, ocular surface failure, and vision loss. Identifying the source of damage for LSCD is critical in the treatment process, given that therapy may extend beyond the scope of the standard protocol, including artificial tears, refractive surgery, and allogeneic stem cell transplants. This comprehensive review of the literature demonstrates the various genetic, acquired, and immunological causes of LSCD and the spectrum of supplemental therapies available.

Ocular-Surface Regeneration Therapies for Eye Disorders: The State of the Art

The ocular surface is a complex structure that includes cornea, conjunctiva, limbus, and tear film, and is critical for maintaining visual function. When the ocular-surface integrity is altered by a disease, conventional therapies usually rely on topical drops or tissue replacement with more invasive procedures, such as corneal transplants. However, in the last years, regeneration therapies have emerged as a promising approach to repair the damaged ocular surface by stimulating cell proliferation and restoring the eye homeostasis and function. This article reviews the different strategies employed in ocular-surface regeneration, including cell-based therapies, growth-factor-based therapies, and tissue-engineering approaches. Dry eye and neurotrophic keratopathy diseases can be treated with nerve-growth factors to stimulate the limbal stem-cell proliferation and the corneal nerve regeneration, whereas conjunctival autograft or amniotic membrane are used in subjects with corneal limbus dysfunction, such as limbal stem-cell deficiency or pterygium. Further, new therapies are available for patients with corneal endothelium diseases to promote the expansion and migration of cells without the need of corneal keratoplasty. Finally, gene therapy is a promising new frontier of regeneration medicine that can modify the gene expression and, potentially, restore the corneal transparency by reducing fibrosis and neovascularization, as well as by stimulating stem-cell proliferation and tissue regeneration.

Research progress on the mechanism of ferroptosis and its role in diabetic retinopathy

Ferroptosis is iron-dependent regulatory cell death (RCD). Morphologically, ferroptosis is manifested as mitochondrial atrophy and increased mitochondrial membrane density. Biochemically, ferroptosis is characterized by the depletion of glutathione (GSH), the inactivation of glutathione peroxidase 4 (GPX4), and an increase in lipid peroxides (LPO)and divalent iron ions. Ferroptosis is associated with various diseases, but the relationship with diabetic retinopathy(DR) is less studied. DR is one of the complications of diabetes mellitus and has a severe impact on visual function. The pathology of DR is complex, and the current treatment is unsatisfactory. Therefore, exploring pathogenesis is helpful for the clinical treatment of DR. This paper reviews the pathological mechanism of ferroptosis and DR in recent years and the involvement of ferroptosis in the pathology of DR. In addition, we propose problems that need to be addressed in this research field. It is expected to provide new ideas for treating DR by analyzing the role of ferroptosis in DR.

Conjunctivitis: A Primer on Conjunctival Biopsy and Approach to Histopathologic Diagnosis

Conjunctivitis, or inflammation of the mucosal covering the anterior third of sclera and inner eyelid, is a common clinical condition of varied causation. Most cases are self-limited due to infection or allergy and rarely necessitate biopsy. Inflammation of the conjunctiva, however, is one of the most common principal histopathologic diagnoses rendered when the tissue is biopsied. In the context of conjunctivitis, biopsy is usually performed when inflammation is chronic and recalcitrant to therapy, has clinically atypical features, or requires an etiologic diagnosis when one cannot be reached through other laboratory methods. The exclusion of ocular surface neoplasia in a chronically inflamed conjunctiva is a common justification for biopsy. When inflammation is the principal histopathology finding, it is desirable-whenever feasible-to establish the cause. This brief review provides a guide in how histologic findings of an inflamed conjunctiva can direct the clinical evaluation towards an etiologic diagnosis.

Oxidative stress and visual system: a review

Different types of tissues respond differently to the action of oxidative stress. The visual system is very sensitive to oxidative action due to continuous exposure to light. In consideration of the growing interest of scientific studies towards various compounds endowed with antioxidant and anti-inflammatory properties, we performed a review of the literature focusing on the use of some antioxidant molecules for the treatment of conditions affecting the visual system. In this study, we focused on the ability of two antioxidant agents, the small molecule α-lipoic acid (ALA) and the enzyme superoxide dismutase (SOD), to influence the neurodegenerative physiological processes related to aging and oxidative stress affecting the ocular segment. The literature data report that ALA and SOD can protect against neurodegenerative effects both the optic nerve and retina and, if administered together, they are able to lower the levels of oxidative stress, thus preventing neurodegeneration and reducing the apoptotic process.

A Review of the Diagnosis and Treatment of Limbal Stem Cell Deficiency

Limbal stem cell deficiency (LSCD) can cause significant corneal vascularization and scarring and often results in serious visual morbidity. An early and accurate diagnosis can help prevent the same with a timely and appropriate intervention. This review aims to provide an understanding of the different diagnostic tools and presents an algorithmic approach to the management based on a comprehensive clinical examination. Although the diagnosis of LSCD usually relies on the clinical findings, they can be subjective and non-specific. In such cases, using an investigative modality offers an objective method of confirming the diagnosis. Several diagnostic tools have been described in literature, each having its own advantages and limitations. Impression cytology and in vivo confocal microscopy (IVCM) aid in the diagnosis of LSCD by detecting the presence of goblet cells. With immunohistochemistry, impression cytology can help in confirming the corneal or conjunctival source of epithelium. Both IVCM and anterior segment optical coherence tomography can help supplement the diagnosis of LSCD by characterizing the corneal and limbal epithelial changes. Once the diagnosis is established, one of various surgical techniques can be adopted for the treatment of LSCD. These surgeries aim to provide a new source of corneal epithelial stem cells and help in restoring the stability of the ocular surface. The choice of procedure depends on several factors including the involvement of the ocular adnexa, presence of systemic co-morbidities, status of the fellow eye and the comfort level of the surgeon. In LSCD with wet ocular surfaces, autologous and allogeneic limbal stem cell transplantation is preferred in unilateral and bilateral cases, respectively. Another approach in bilateral LSCD with wet ocular surfaces is the use of an autologous stem cell source of a different epithelial lineage, like oral or nasal mucosa. In eyes with bilateral LSCD with significant adnexal issues, a keratoprosthesis is the only viable option. This review provides an overview on the diagnosis and treatment of LSCD, which will help the clinician choose the best option amongst all the therapeutic modalities currently available and gives a clinical perspective on customizing the treatment for each individual case.

Cicatricial Conjunctivitis and Concurrent Clinical Features: A Case Study

Purpose:

We report a case of cicatricial conjunctivitis to illustrate the clinical approach for management of such a case. This is a 52-year-old Chinese man who presented with bilateral red eyes associated with itching for a year. He had a history of chronic itchy rash in the chest and the arms. Otherwise there was no history of autoimmune disease, asthma, sinusitis, or drug allergy. On examination, he had diffuse hyperemia over both conjunctivae, with symblepharon involving the inferior bulbar and palpebral conjunctivae, associated with cicatrization of the caruncles, and obliteration of inferior lacrimal puncta. There were mild subtarsal papillary reaction with Meibomian gland dysfunction and presence of inferior mis-directed eyelashes. The corneas showed multiple foci of superficial epitheliopathy. A clinical diagnosis of chronic cicatricial conjunctivitis was made, with differential diagnosis of chronic atopic allergic conjunctivitis. Conjunctival biopsy was performed from the inferior conjunctival adhesions and it showed patchy chronic stromal inflammation with focal lymphoplasmacytic sub-epithelial infiltrates and loss of goblet cells. The stroma shows marked fibrosis, with no evidence of mast cells or eosinophils. In particular, there were no deposits of IgA, IgM, C3, and fibrinogen in the basement membrane. The patient was treated with topical loteprednol, glucocorticoids and artificial tears, and his symptoms improved after treatment.

Conclusion:

We present a man with cicatricial conjunctivitis with chronic subconjunctival inflammation and fibrosis but no immune deposits in the conjunctival basement membrane on histology, to illustrate the clinical approach and diagnostic challenges in managing such a case.

Perioperative Management and Long-Term Outcomes in Ocular Cicatricial Pemphigoid Patients Undergoing Cataract Surgery

Objective

To observe the outcomes of cataract surgery in ocular cicatricial pemphigoid (OCP) patients and explore routine perioperative medical treatments.

Design

Retrospective case series.

Methods

Fourteen eyes of 8 patients were included in the study. Foster's stage 1-4 OCP patients were given human intravenous immunoglobulin, whereas patients with active inflammation were treated with prednisone tablets and methotrexate. Those who were intolerant to methotrexate and had severe inflammatory symptoms were treated with cyclophosphamide. Cataract surgery was performed for all patients after three months of systemic treatment under stable conditions. The conjunctival biopsy was evaluated by immunofluorescence microscopy. Then, patients were divided into individuals with or without ankyloblepharon. Records were reviewed for OCP stage, type of surgery, best-corrected visual acuity (BCVA), Schirmer I test, corneal fluorescein sodium staining, meibomian gland coloboma range, and ocular surface disease index (OSDI) scores. Follow-up was for the duration of taking topical and systemic medication.

Results

Nine female (64.29%) and 4 male (35.71%) eyes were diagnosed with OCP by biopsy. The mean follow-up time was 60.64 ± 35.62 months. Thirteen eyes (92.86%) of 7 patients underwent phacoemulsification. One eye underwent phacoemulsification combined with amniotic membrane transplantation. The intracapsular extraction of cataract was applied to one eye. The BCVA improved significantly in all the patients, which remained stable until the last follow-up. The Schirmer I test was higher than that before the surgery. Corneal fluorescein sodium staining after surgery showed a decrease in score compared to the preoperative score. The BCVA of the patients after surgery increased significantly. The OSDI scores of patients with ankyloblepharon were significantly higher than for those without it. Postoperative symblepharon showed no significant difference compared to the preoperative symblepharon.

Conclusions

In this series, OCP patients with cataracts were able to undergo phacoemulsification surgery, whereas routine use of immunosuppression and closed postoperative follow-up were necessary.

Efficacy and Safety of Antivascular Endothelial Growth Factor (Anti-VEGF) in Treating Neovascular Age-Related Macular Degeneration (AMD): A Systematic Review and Meta-analysis

This study is aimed at assessing the efficacy and safety of antivascular endothelial growth factor (anti-VEGF) inhibitors in treating age-related macular degeneration (AMD). PubMed, Embase, and Cochrane library were searched. Weighted mean difference (WMD) and relative risk (RR) with 95% confidence interval (CI) were applied to assess outcomes. Eighteen randomized controlled trials involved 8,847 neovascular AMD patients were selected for the meta-analysis. Pegaptanib (WMD: 6.70; $P<0.001$ ) and ranibizumab (WMD: 17.80; $P<0.001$ ) were associated with greater BCVA changes than control after 1 year. Bevacizumab was linked with less changes in central macular thickness after 1 year compared to control (WMD: -38.50; $P<0.001$ ), but more changes compared to ranibizumab (WMD: 10.69; $P=0.024$ ). The incidence of gain of 15 or more letter visual acuity after 1 year was increased when compared with bevacizumab versus control (RR: 7.80; $P=0.001$ ), pegaptanib versus control (RR: 2.83; $P=0.015$ ), and ranibizumab versus control (RR: 3.92; $P=0.003$ ). Moreover, ranibizumab was associated with more BCVA changes and an increased incidence of gain of 15 or more letter visual acuity after 2 years compared with control (RR: 5.77; $P<0.001$ ). This study found that most anti-VEGF inhibitors provided better efficacy than non-anti-VEGF intervention, and the treatment effectiveness among various anti-VEGF agents was equally effective.

Biochemical Functions and Clinical Characterizations of the Sirtuins in Diabetes-Induced Retinal Pathologies

Diabetic retinopathy (DR) is undoubtedly one of the most prominent causes of blindness worldwide. This pathology is the most frequent microvascular complication arising from diabetes, and its incidence is increasing at a constant pace. To date, the insurgence of DR is thought to be the consequence of the intricate complex of relations connecting inflammation, the generation of free oxygen species, and the consequent oxidative stress determined by protracted hyperglycemia. The sirtuin (SIRT) family comprises 7 histone and non-histone protein deacetylases and mono (ADP-ribosyl) transferases regulating different processes, including metabolism, senescence, DNA maintenance, and cell cycle regulation. These enzymes are involved in the development of various diseases such as neurodegeneration, cardiovascular pathologies, metabolic disorders, and cancer. SIRT1, 3, 5, and 6 are key enzymes in DR since they modulate glucose metabolism, insulin sensitivity, and inflammation. Currently, indirect and direct activators of SIRTs (such as antagomir, glycyrrhizin, and resveratrol) are being developed to modulate the inflammation response arising during DR. In this review, we aim to illustrate the most important inflammatory and metabolic pathways connecting SIRT activity to DR, and to describe the most relevant SIRT activators that might be proposed as new therapeutics to treat DR.

Mucous membrane pemphigoid

Mucous membrane pemphigoid (MMP) is a clinically and immunopathologically heterogenous disease with an incidence of about 2/million inhabitants/year in central Europe. Pemphigoid diseases are characterized by autoantibodies against structural proteins of the epidermis and/or surface-close epithelia. MMP has been defined as pemphigoid disease with predominant mucosal lesions. Most frequently, the oral cavity and the conjunctivae are affected. Lesions outside the mouth tend to heal with scarring leading to visual impairment and finally blindness, as well as, more rarely, impairment of breathing and food intake. Autoantibodies target BP180 (collagen type XVII), laminin 332, BP230 (nearly always in conjunction with other antigens), and type VII collagen in about 75%, 10-20%, 10-30%, and <5% of MMP patients, respectively. While the main autoantibody isotype is IgG, additional, and less frequently, exclusive IgA autoantibodies can be detected in the majority of patients. Assaying for anti-laminin 332 reactivity is pivotal, since in about a quarter of patients with anti-laminin 332 MMP, a malignancy, mainly solid cancers, is associated. The pathophysiology of MMP is yet incompletely understood. A recent mouse model of anti-laminin 332 MMP replicating characteristic clinical and immunopathological findings of the human disease may be helpful to close this knowledge gap. Diagnosis is established by the clinical picture with predominant mucosal lesions and visualization of tissue-bound anti-basement membrane zone antibodies by direct immunofluorescence microscopy. In recent S3 guidelines initiated by the European Academy of Dermatology and Venereology, the clinical spectrum and diagnostic strategies are detailed. In addition, treatment regimens for different clinical situations including patients with exclusive oral or ocular involvement are outlined. Future studies are needed to better understand the clinal complexity and associations as well as to establish widely available diagnostic assays and evidence-based therapeutic strategies.

Chronic Early-Stage Ocular Cicatricial Pemphigoid

Ocular cicatricial pemphigoid (OCP) represents an insidious, autoimmune-mediated disease of the conjunctiva, initially presenting as chronic conjunctivitis and progressing to fibrosis, cicatrization, and eventually blindness secondary to corneal keratinization. This series reports 3 cases presenting with chronic conjunctivitis lasting an average of 10 years without cicatrix formation, ultimately diagnosed as OCP based on direct immunofluorescence of conjunctival biopsy samples. This chronic conjunctivitis without fibrosis suggests the possibility of an OCP subtype with a prolonged early stage or prodrome prior to cicatrization, which may benefit from early diagnosis and treatment to prevent complications of this disease.

Knockdown of LncRNA SNHG1 Suppresses Corneal Angiogenesis by the Regulation of miR-195-5p/VEGF-A

LncRNA SNHG1 (SNHG1) has been widely studied as the causative factor of angiogenesis and proliferative agent in gastric, lung, cervical, and hepatocellular carcinomas. However, its significance of angiogenesis and progression of corneal neovascularization (CRNV) is least understood. This study focuses on the molecular mechanisms followed by SNHG1 to establish CRNV and its angiogenesis. Bioinformatics analysis to identify potential miRNA targets of SNHG1 and vascular endothelial growth factor A (VEGF-A) was conducted using StarBase and was subsequently confirmed by the luciferase reporter assay. Relative quantitative expression of SNHG1 in human umbilical vein endothelial cells (HUVECs) was detected through qRT-PCR and western blot analysis. Cell proliferation was detected through CCK-8 assay, whereas migratory abilities of the cells were determined with transwell assay. A capillary-like tube formation assay was performed to detect the tube formation ability of the cells. Following this, relative expression of miR-195-5p and VEGF-A was determined through qRT-PCR and western blot analysis. Results from the experiments manifested upregulated levels of SNHG1 and VEGF-A in HUVECs and CRNV tissues as compared with the control group, whereas downregulated levels of miR-195-5p were measured in the CRNV tissues and HUVECs, suggesting the negative correlation between lncRNA and miRNA. Overexpressed vascular endothelial growth factor promoted cell proliferation and tube formation; however, its silencing leads to inhibition in angiogenesis and proliferation. Potential binding sites of SNHG1 showed miR-195-5p as its direct target and SNHG1 as a sponge for this miRNA. Knockdown and downregulated levels of SNHG1 showed a notable decrease and inhibition in angiogenesis and migration of CRNV cells. The study showed that SNHG1 inhibition significantly reduced cell proliferation, migration, and tube formation in HUVECs transfect with lncRNA SNHG1. Mechanistic insights into the SNHG1 showed that SNHG1 acts as a sponge for miR-195-5p and upregulates the levels of VEGF-A.

Ocular mucous membrane pemphigoid: novel treatment strategies

PURPOSE OF REVIEW

To describe current treatments of ocular mucous membrane pemphigoid (OMMP), including conventional systemic immunosuppression (CIST) and novel biologic agents.

RECENT FINDINGS

CIST remains the main stay therapy for the management of OMMP. The choice of agents is tailored to disease severity - mild disease is treated with dapsone, whereas moderately severe cases are often treated with mycophenolate mofetil or sulfa-based drugs and severe cases are treated with cyclophosphamide. In recalcitrant disease newer biologics such as Rituximab, intravenous immunoglobins and tumour necrosis alpha antagonists have proven to be effective in disease control. Control of inflammation with topical therapy and halting conjunctival fibrosis remain as areas of unmet clinical needs.

SUMMARY

OMMP is largely treated with CIST. The recent introduction of new biologic agents could shape the way the disease is treated in the near future.

Differential gene expression of the healthy conjunctiva during the day

PURPOSE

To determine if there is diurnal variation in gene expression in normal healthy conjunctival cells.

METHODS

Bulbar conjunctival swab samples were collected from four healthy subjects in the morning and evening of the same day. The two swab samples were taken from one eye of each participant, with a minimum of five hours gap between the two samples. RNA was extracted and analysed using RNA sequencing (RNA-Seq).

RESULTS

A total of 121 genes were differentially expressed between the morning and the evening conjunctival samples, of which 94 genes were upregulated in the morning, and 27 genes were upregulated in the evening. Many of the genes that were upregulated in the morning were involved in defence, cell turnover and regulation of gene expression, while the genes upregulated in the evening were involved in signalling and mucin production.

CONCLUSIONS

This study has identified several genes whose expression changes over the course of the day. Knowledge of diurnal variations of conjunctival gene expression provides an insight into the regulatory status of the healthy eye and provides a baseline for examining changes during ocular surface disease.

Development of pemphigus foliaceus in a mucous membrane pemphigoid patient: An insight into possible mechanism eliciting a distinct autoimmune bullous disease in a rare anti-basement membrane autoimmunity

Mucous membrane pemphigoid (MMP) rarely coexists with another autoimmune bullous disease (AIBD). Herein, we report an extremely rare MMP case who sequentially developed pemphigus foliaceus (PF). A 72-year-old man had been treated by azathioprine monotherapy for anti-BP180 MMP for 1.5 years. Clinical findings suggestive of PF, represented by scaly erythema and erosions, started to appear approximately 1 month after the episode of diarrhea. Serological and immunohistochemical examinations confirmed the diagnosis of PF. The mucocutaneous lesions were controlled by oral azathioprine and topical corticosteroids. To our knowledge, this is a previously unreported case of PF coexistent with MMP. A literature review of MMP cases associated with AIBD elucidated that 16 out of 18 cases simultaneously developed MMP and AIBD, while only two cases were diagnosed sequentially by the changes in clinical symptoms similar to our case. The titer of anti-desmoglein 1 antibodies lineally correlated with the changes in the severity of scaly erythema. Mild but noticeable exacerbation of mucosal erosion prior to the gradual increase in anti-BP180-NC16a antibodies was also noted. Unlike in other cases where MMP/AIBD coexisted, sequential development of autoantibodies in our case cannot be explained by the epitope-spreading theory as autoantigens are micro-anatomically isolated from one other. The preceding viral infection and/or continuous moderate inflammation due to azathioprine monotherapy for MMP might have contributed to the development of PF in our case.

[Paraneoplastic autoimmune dermatoses]

Paraneoplastic skin manifestations associated with malignancies are extremely polymorphous. Clinicians should be familiar with paraneoplastic dermatoses to establish an early diagnosis of the underlying neoplasm. Lack of familiarity with cutaneous clues for internal malignancies may delay diagnosis and treatment of cancer. In this review, we describe several paraneoplastic autoimmune dermatoses, including paraneoplastic autoimmune multiorgan syndrome, paraneoplastic bullous pemphigoid, and paraneoplastic dermatomyositis.

Current Insights Into 3D Bioprinting: An Advanced Approach for Eye Tissue Regeneration

Three-dimensional (3D) printing is a game changer technology that holds great promise for a wide variety of biomedical applications, including ophthalmology. Through this emerging technique, specific eye tissues can be custom-fabricated in a flexible and automated way, incorporating different cell types and biomaterials in precise anatomical 3D geometries. However, and despite the great progress and possibilities generated in recent years, there are still challenges to overcome that jeopardize its clinical application in regular practice. The main goal of this review is to provide an in-depth understanding of the current status and implementation of 3D bioprinting technology in the ophthalmology field in order to manufacture relevant tissues such as cornea, retina and conjunctiva. Special attention is paid to the description of the most commonly employed bioprinting methods, and the most relevant eye tissue engineering studies performed by 3D bioprinting technology at preclinical level. In addition, other relevant issues related to use of 3D bioprinting for ocular drug delivery, as well as both ethical and regulatory aspects, are analyzed. Through this review, we aim to raise awareness among the research community and report recent advances and future directions in order to apply this advanced therapy in the eye tissue regeneration field.

Anti-VEGF Treatment in Corneal Diseases

BACKGROUND

Corneal neovascularization (CN) is a clue feature of different ocular pathological conditions and can lead to corneal edema and opacification with subsequent vision loss. Vascular endothelial growth factor (VEGF), which plays a key role in new vessels formation, proliferation and migration, was found to be up-regulated in these conditions. Nowadays, it is possible to downregulate the angiogenic process by using anti-VEGF agents administered by different routes.

OBJECTIVE

To evaluate the efficacy, safety and possible future directions of anti-VEGF agents used for the treatment of CNV owing to different aetiologies.

METHODS

A computerized search of articles dealing with the topic of anti-VEGF therapy in CN was conducted in PubMed, Scopus and Medline electronic databases. The following key phrases were used: anti-VEGF agents, corneal neovascularization, bevacizumab, ranibizumab, vascular endothelial growth factor, angiogenesis.

RESULTS

The use of anti-VEGF therapy in the treatment of CN reduced pathological vessel density without causing significant side effects. Various administration routes such as topical, subconjunctival and intrastromal ones are available, and the choice depends on patient and disease characteristics. Much more effectiveness is achieved in case of early administration before mature and wellestablished vessels take place. A combined approach between various drugs including anti-VEGF agents should be adopted in those cases at higher risk of neovascularization recurrence such as chronic long-standing diseases where ischemic and inflammatory stimuli are not definitively reversed.

CONCLUSION

The efficacy and safety of anti-VEGF agents support their adoption into the daily clinical practice for the management of CN.