Endoplasmic Reticulum Stress and Unfolded Protein Response in Vernal Keratoconjunctivitis

Purpose

Vernal keratoconjunctivitis (VKC) is an ocular allergic disease characterized by a type 2 inflammation, tissue remodeling, and low quality of life for the affected patients. We investigated the involvement of endoplasmic reticulum (ER) stress and unfolded protein response in VKC.

Methods

Conjunctival imprints from VKC patients and normal subjects (CTs) were collected, and RNA was isolated, reverse transcribed, and analyzed with the Affymetrix microarray. Differentially expressed genes between VKC patients and CTs were evaluated. Genes related to ER stress, apoptosis, and autophagy were further considered. VKC and CT conjunctival biopsies were analyzed by immunohistochemistry (IHC) with specific antibodies against unfolded protein response (UPR), apoptosis, and inflammation. Conjunctival fibroblast and epithelial cell cultures were exposed to the conditioned medium of activated U937 monocytes and analyzed by quantitative PCR for the expression of UPR, apoptosis, autophagy, and inflammatory markers.

Results

ER chaperones HSPA5 (GRP78/BiP) and HYOU1 (GRP170) were upregulated in VKC patients compared to CTs. Genes encoding for ER transmembrane proteins, PKR-like ER kinase (PERK), activating transcription factor 6 (ATF6), ER-associated degradation (ERAD), and autophagy were upregulated, but not those related to apoptosis. Increased positive reactivity of BiP and ATF6 and unchanged expression of apoptosis markers were confirmed by IHC. Cell cultures in stress conditions showed an overexpression of UPR, proinflammatory, apoptosis, and autophagy markers.

Conclusions

A significant overexpression of genes encoding for ER stress, UPR, and pro-inflammatory pathway components was reported for VKC. Even though these pathways may lead to ER homeostasis, apoptosis, or inflammation, ER stress in VKC may predominantly contribute to promote inflammation.

Evaluation of Autophagy in Conjunctival Fibroblasts

Vernal keratoconjunctivitis (VKC) is a serious eye allergy characterized by poorly understood pathogenic mechanisms and a lack of effective treatments. Autophagy, a process involved in both triggering and suppressing immune and inflammatory responses, plays a role in VKC's pathophysiology. Understanding autophagy's involvement in VKC could lead to new treatment possibilities, such as utilizing specific topical substances to induce or inhibit autophagy and prevent severe complications of this eye condition. In our current protocol, we present a robust methodology established in our laboratory for studying autophagy in primary conjunctival fibroblasts. We assess autophagy through techniques like immunocytochemistry, immunoblotting, and qPCR.

Coexistence of neuropathic corneal pain, corneal nerve abnormalities, depression, and low quality of life

PURPOSE

To evaluate the quality of life (QoL), mental health conditions and corneal morphology in neuropathic corneal pain (NCP) subjects without a significant ocular surface disease.

METHODS

A composite questionnaire was administered to 228 consecutive subjects, assessing the pain intensity, duration, and quality using a modified version of the Self-Administered Leeds Assessment of Neuropathic Symptoms and Signs (S-LANSS) and Pain Detect (PD) questionnaires. Subjects diagnosed with possible central NCP and two sub-groups of patients diagnosed with peripheral ocular pain completed an additional battery of mental health questionnaires and were examined by In Vivo Confocal Microscopy (IVCM).

RESULTS

Of the 76 subjects that reported chronic ocular pain (duration >1 month), 53 were classified with probable NCP. Nine subjects without signs that justify the pain and non-responding to topical anaesthesia, were considered affected by central NCP. In these patients, a significant negative correlation was found between the presence pain and the mental component of the QoL (R2 = 0.733), and a positive correlation between the severity of pain the presence post-traumatic stress disorder (R2 = 0.83) and depression (R2 = 0.93). Although neuromas and sprouting had higher frequency in the central NCP group compared the control groups, these differences was not statistically different.

CONCLUSIONS

The assessment of ocular pain characteristics using multiple questionnaires and IVCM may help to recognize differences between nociceptive and neuropathic pain. An association between pain intensity and mental health condition may guide the therapeutical choices.

NOVATIVE: A Phase II/III, Multicenter, Double-masked, Randomized Study of Cyclosporine A 0.05% and 0.1% Ophthalmic Cationic Emulsion Versus Vehicle in Patients with Vernal Keratoconjunctivitis

PURPOSE

This study evaluates the efficacy and tolerability of cyclosporine A cationic emulsion (CsA-CE) in patients ≥4 years of age with moderate-to-severe vernal keratoconjunctivitis (VKC).

METHODS

This Phase II/III, multicenter, double-masked, dose-ranging study had 2 treatment periods: a 4-week, randomized, vehicle-controlled period in which patients received 0.05% CsA-CE, 0.1% CsA-CE, or vehicle eye drops 4 times daily (period 1) and a 3-month period in which patients received 0.05% CsA-CE or 0.1% CsA-CE 2 or 4 times daily (period 2). The primary efficacy end point was rating of subjective symptoms at day 28 in period 1 per the BenEzra scale.

FINDINGS

All groups showed improvement in subjective VKC symptoms at day 28, without a statistically significant difference between 0.05% or 0.1% CsA-CE vs vehicle. Both CsA-CE doses produced statistically significant improvements in corneal fluorescein staining scores vs vehicle at day 28; improvements were evident as early as week 1 and continued through month 1. Progressive reduction in subjective itching was evident after week 1 and continued through month 1. Treatment for an additional 3 months further improved subjective symptoms and objective signs of VKC in both CsA-CE groups. Improvement was most notable with 0.1% CsA-CE in patients with severe keratitis. The safety and tolerability profile is favorable.

IMPLICATIONS

Although treatment with 0.05% and 0.1% CsA-CE showed clinical efficacy in alleviating keratitis and itching as early as week 1, with sustained benefit through 1 month, the primary efficacy end point was not met. These findings informed the design of the Phase III trial of 0.1% CsA-CE (Vernal Keratoconjunctivitis Study).

CLINICALTRIALS

gov identifier: NCT00328653.

Efficacy and Satisfaction of Cyclosporine 0.1% in Patients with Vernal Keratoconjunctivitis

Vernal keratoconjunctivitis (VKC) is a severe form of ocular allergy that compromises the quality of life of affected patients. Topical cyclosporine 0.1% cationic emulsion (CsA-CE) has been recently authorized for the treatment of severe VKC. We treated 29 VKC patients with on-label CsA-CE and recorded signs and symptoms, subjective patient's treatment satisfaction and the additional use of topical corticosteroids in case of exacerbations. CsA-CE was effective in reducing signs and symptoms in daily clinical practice. The overall subjective improvement of symptoms, efficacy of the treatment, tolerability to the drug and compliance reached a high level of subjective satisfaction score.55% of treated patients required the additional use of a 3-day course of topical dexamethasone with 1.13 ± 0.81 mean courses/month. In conclusions, VKC patients reported an overall high satisfaction with used the on-label topical CsA-CE with a limited use of additional topical corticosteroid treatment.

Impaired autophagy in the lower airways and lung parenchyma in stable COPD

Background

There is increasing evidence of autophagy activation in COPD, but its role is complex and probably regulated through cell type-specific mechanisms. This study aims to investigate the autophagic process at multiple levels within the respiratory system, using different methods to clarify conflicting results reported so far.

Methods

This cross-sectional study was performed on bronchial biopsies and peripheral lung samples obtained from COPD patients (30 and 12 per sample type, respectively) and healthy controls (25 and 22 per sample type, respectively), divided by smoking history. Subjects were matched for age and smoking history. We analysed some of the most important proteins involved in autophagosome formation, such as LC3 and p62, as well as some molecules essential for lysosome function, such as lysosome-associated membrane protein 1 (LAMP1). Immunohistochemistry was used to assess the autophagic process in both sample types. ELISA and transcriptomic analysis were performed on lung samples.

Results

We found increased autophagic stimulus in smoking subjects, regardless of respiratory function. This was revealed by immunohistochemistry through a significant increase in LC3 (p<0.01) and LAMP1 (p<0.01) in small airway bronchiolar epithelium, alveolar septa and alveolar macrophages. Similar results were obtained in bronchial biopsy epithelium by evaluating LC3B (p<0.05), also increased in homogenate lung tissue using ELISA (p<0.05). Patients with COPD, unlike the others, showed an increase in p62 by ELISA (p<0.05). No differences were found in transcriptomics analysis.

Conclusions

Different techniques, applied at post-transcriptional level, confirm that cigarette smoke stimulates autophagy at multiple levels inside the respiratory system, and that autophagy failure may characterise COPD.

Ciclosporin A Cationic Emulsion 0.1% for the Management of Dry Eye Disease: Facts That Matter for Eye-Care Providers

Dry eye disease (DED) is a chronic inflammatory disease of the ocular surface requiring long-term therapy. Severe forms of DED generally do not respond to tear substitutes alone or combined, and often require treatment with topical anti-inflammatory agents to break the vicious circle of inflammation. This review summarises data from randomised controlled trials and real-world evidence on the efficacy and safety of ciclosporin A 0.1% cationic emulsion (Ikervis®) for the management of DED. Improvements in clinical signs and symptoms were reported from as early as 4 weeks after treatment initiation, although it can take a few months to reach the full benefits. Treatment periods of up to 12 months provide sustained benefit to patients. In the most responsive patients, treatment discontinuation is possible with no further substantial relapse over 12 months in over 65% of patients. Transient local ocular effects are the most commonly reported adverse events.

Diagnostic criteria of chronic conjunctivitis: atopic keratoconjunctivitis and vernal keratoconjunctivitis

PURPOSE OF REVIEW

Chronic ocular allergies, vernal (VKC) and atopic keratoconjunctivitis (AKC) are relatively rare conditions that require definite diagnostic criteria to the most appropriate therapeutical approach.

RECENT FINDINGS

The diagnosis of both VKC and AKC is generally based on clinical history, signs and symptoms, and the results of allergic tests, which allow to identify the different diseases phenotypes. However, other subtypes of the two diseases and/or overlaps may occur making the diagnosis non always so clear, such as VKC and AKC overlaps or adult-like VKC disease. Each of these phenotypes may be sustained by different mechanisms which are still not well defined but not only related to a type 2 inflammation. The further challenges will be to correlate clinical or molecular biomarkers to a single subtype or disease severity.

SUMMARY

Definite criteria of chronic allergies will further guide to more specific therapeutical approaches.

Topical cyclosporine A cationic ophthalmic emulsion in paediatric vernal keratoconjunctivitis: pooled analysis of randomised NOVATIVE and VEKTIS trials

BACKGROUND/OBJECTIVES

Cyclosporine A cationic ophthalmic emulsion (CsA CE) was evaluated in paediatric and adolescent patients with vernal keratoconjunctivitis (VKC) in the NOVATIVE (NCT00328653) and VEKTIS (NCT01751126) trials. The similarity of these studies permitted pooled assessment of the effect of CsA CE on corneal damage as well as safety and tolerability.

SUBJECTS/METHODS

Pooled outcomes were assessed for the first 28 days of treatment. In NOVATIVE, 118 patients were randomised to 4 times daily (QID) CsA CE 0.05%, 0.1%, or vehicle eye drops. In VEKTIS, 169 patients were randomised to CsA CE 0.1% QID or twice daily (BID) or vehicle. For these analyses, treatment groups comprised: (1) pooled CsA CE 0.1% QID arms (high-dose; n = 96); (2) pooled CsA CE 0.05% QID arm from NOVATIVE and CsA CE 0.1% BID data from VEKTIS (low-dose; n = 93); and (3) pooled vehicle QID arms (vehicle; n = 98).

RESULTS

Changes from baseline to day 28 (mean ± standard deviation) in corneal fluorescein staining (CFS) scores for CsA CE high-dose, low-dose, and vehicle groups were -1.6 ± 1.47 (95% CI: -0.9, -0.1; p = 0.0124 vs vehicle), -1.7 ± 1.39 (95% CI: -1.1, -0.3; p = 0.0015 vs vehicle), and -1.0 ± 1.55, respectively. Adverse events (AEs) of any type were reported in 37.5%, 34.4%, and 37.8% of the high-dose, low-dose, and vehicle groups, respectively. Most were mild or moderate in severity.

CONCLUSIONS

CsA CE significantly decreased corneal damage and was safe and well tolerated in patients with VKC. These data support CSA CE as a treatment option for the management of VKC.

Meta-Analysis of Keratoconus Transcriptomic Data Revealed Altered RNA Editing Levels Impacting Keratin Genomic Clusters

Introduction

Keratoconus (KC) is an ocular disorder with a multifactorial origin. Transcriptomic analyses (RNA-seq) revealed deregulations of coding (mRNA) and non-coding RNAs (ncRNAs) in KC, suggesting that mRNA-ncRNA co-regulations can promote the onset of KC. The present study investigates the modulation of RNA editing mediated by the adenosine deaminase acting on dsRNA (ADAR) enzyme in KC.

Materials

The level of ADAR-mediated RNA editing in KC and healthy corneas were determined by two indexes in two different sequencing datasets. REDIportal was used to localize known editing sites, whereas new putative sites were de novo identified in the most extended dataset only and their possible impact was evaluated. Western Blot analysis was used to measure the level of ADAR1 in the cornea from independent samples.

Results

KC was characterized by a statistically significant lower RNA-editing level compared to controls, resulting in a lower editing frequency, and less edited bases. The distribution of the editing sites along the human genome showed considerable differences between groups, particularly relevant in the chromosome 12 regions encoding for Keratin type II cluster. A total of 32 recoding sites were characterized, 17 representing novel sites. JUP, KRT17, KRT76, and KRT79 were edited with higher frequencies in KC than in controls, whereas BLCAP, COG3, KRT1, KRT75, and RRNAD1 were less edited. Both gene expression and protein levels of ADAR1 appeared not regulated between diseased and controls.

Conclusions

Our findings demonstrated an altered RNA-editing in KC possibly linked to the peculiar cellular conditions. The functional implications should be further investigated.

The Management of Dry Eye Disease: Proceedings of Italian Dry Eye Consensus Group Using the Delphi Method

Dry eye disease (DED) is a highly prevalent, chronic and progressive condition that affects 5-33% of the world's adult population [...].

The multifaceted aspects of ocular allergies: Phenotypes and endotypes

Like the lung, skin, and nose, the external eye is a common target of allergic inflammation. Ocular allergy (OA) represents a collection of underestimated diseases of the eye observed in children and adults. The ocular manifestations are the expression of multifactorial immune mechanisms that generally have a good prognosis, but for a few patients, long term inflammation may remarkably reduce the visual function. Evidence suggests that other co-participant systems, including epigenetic, genetic, environmental, individual factors, sex hormones, and the central and autonomic nervous systems may influence the ocular response from distant sites. This is consistent with the concept that the eye is an organ fully integrated with the rest of the body and that the therapeutic approach should be holistic, dynamic, and personalized. For instance, androgens and estrogens binding to receptors on the ocular surface and the continuous cross-talking of neuromediators and growth factors with immune cells act to maintain the ocular surface homeostasis in response to environmental challenges. The immune system links and regulates the response of the ocular surface. Complex and incompletely understood mechanisms influence the innate and adaptive immune responses and generate different OA phenotypes and endotypes discussed in the present review.

Epithelial barrier dysfunction in ocular allergy

The epithelial barrier is the first line of defense that forms a protective barrier against pathogens, pollutants, and allergens. Epithelial barrier dysfunction has been recently implicated in the development of allergic diseases such as asthma, atopic dermatitis, food allergy, and rhinitis. However, there is limited knowledge on epithelial barrier dysfunction in ocular allergy (OA). Since the ocular surface is directly exposed to the environment, it is important to understand the role of ocular epithelia and their dysfunction in OA. Impaired epithelial barrier enhances allergen uptake, which lead to activation of immune responses and development of chronic inflammation as seen in allergies. Abnormal expression of tight junction proteins that helps to maintain epithelial integrity has been reported in OA but sufficient data not available in chronic atopic (AKC) and vernal keratoconjunctivitis (VKC), the pathophysiology of which is not just complex, but also the current treatments are not completely effective. This review provides an overview of studies, which indicates the role of barrier dysfunction in OA, and highlights how ocular barrier dysfunction possibly contributes to the disease pathogenesis. The review also explores the potential of ocular epithelial barrier repair strategies as preventive and therapeutic approach.

Prevalence and features of delirium in older patients admitted to rehabilitation facilities: a multicenter study

BACKGROUND

Delirium is thought to be common across various settings of care; however, still little research has been conducted in rehabilitation.

AIM

We investigated the prevalence of delirium, its features and motor subtypes in older patients admitted to rehabilitation facilities during the three editions of the "Delirium Day project".

METHODS

We conducted a cross-sectional study in which 1237 older patients (age ≥ 65 years old) admitted to 50 Italian rehabilitation wards during the three editions of the "Delirium Day project" (2015 to 2017) were included. Delirium was evaluated through the 4AT and its motor subtype with the Delirium Motor Subtype Scale.

RESULTS

Delirium was detected in 226 patients (18%), and the most recurrent motor subtype was mixed (37%), followed by hypoactive (26%), hyperactive (21%) and non-motor one (16%). In a multivariate Poisson regression model with robust variance, factors associated with delirium were: disability in basic (PR 1.48, 95%CI: 1.17-1.9, p value 0.001) and instrumental activities of daily living (PR 1.58, 95%CI: 1.08-2.32, p value 0.018), dementia (PR 2.10, 95%CI: 1.62-2.73, p value < 0.0001), typical antipsychotics (PR 1.47, 95%CI: 1.10-1.95, p value 0.008), antidepressants other than selective serotonin reuptake inhibitors (PR 1.3, 95%CI: 1.02-1.66, p value 0.035), and physical restraints (PR 2.37, 95%CI: 1.68-3.36, p value < 0.0001).

CONCLUSION

This multicenter study reports that 2 out 10 patients admitted to rehabilitations had delirium on the index day. Mixed delirium was the most prevalent subtype. Delirium was associated with unmodifiable (dementia, disability) and modifiable (physical restraints, medications) factors. Identification of these factors should prompt specific interventions aimed to prevent or mitigate delirium.

Tracing the SARS-CoV-2 infection on the ocular surface: Overview and preliminary corneoscleral transcriptome sequencing

COVID-19's impact on the ocular surface has already been recognized, however the molecular mechanisms induced by the infection on the ocular surface are still unclear. The aim of this paper is to provide a first overview of the transcriptional perturbations caused by SARS-CoV-2 on the ocular surface by analyzing gene expression profile of corneoscleral ring samples from post-mortem SARS-CoV-2 positive donors (PD). The presence of SARS-CoV-2 on the ocular surface, in tears and corneal tissues has rarely been detected in infected individuals in both the presence and the absence of ocular manifestations. In this preliminary study, 6 human corneoscleral tissues of 3 PD and two tissues from a negative donor (CTRL) were obtained at the local eye bank. The presence of genomic and sub-genomic SARS-CoV-2 RNAs was assessed by qRT-PCR, while transcriptome analysis (RNA-sequencing) was performed by Illumina. Principal Component Analysis (PCA), search for differentially expressed genes (DEGs) and Gene Ontology (GO)-enrichment analysis were performed. Three samples from PD were found positive for SARS-CoV-2 genomic RNA, although the absence of sub-genomic RNAs indicated an inactive virus. PCA analysis grouped 3 different clusters, one including CTRL, and the other two including, respectively, PD with undetected SARS-CoV-2 (PD-SARS-neg) and PD with detected SARS-CoV-2 (PD-SARS-pos). The DEGs in common with the 2 PD clusters included several genes associable to the interferon pathway, such as ADAMTS4, RSAD2, MMP1, IL6, ISG15 and proinflammatory cytokines. Among the down-regulated genes we found AQP5. GO analysis revealed 77 GO terms over-represented in PD-SARS-neg vs. CTRL, and 17 GO terms in PD-SARS-pos vs. CTRL. The presence of SARS-CoV-2 RNA and RNA-sequencing reads in ocular surface tissues supports the possibility that the eye acts as an entry route. The modulation of early responsive genes, together with several ISGs suggests a potential protective responsiveness of the ocular tissues to SARS-CoV-2.

The association between low skeletal muscle mass and delirium: results from the nationwide multi-centre Italian Delirium Day 2017

Introduction

Delirium and sarcopenia are common, although underdiagnosed, geriatric syndromes. Several pathological mechanisms can link delirium and low skeletal muscle mass, but few studies have investigated their association. We aimed to investigate (1) the association between delirium and low skeletal muscle mass and (2) the possible role of calf circumference mass in finding cases with delirium.

Methods

The analyses were conducted employing the cross-sectional “Delirium Day” initiative, on patient 65 years and older admitted to acute hospital medical wards, emergency departments, rehabilitation wards, nursing homes and hospices in Italy in 2017. Delirium was diagnosed as a 4 + score at the 4-AT scale. Low skeletal muscle mass was operationally defined as calf circumference ≤ 34 cm in males and ≤ 33 cm in females. Logistic regression models were used to investigate the association between low skeletal muscle mass and delirium. The discriminative ability of calf circumference was evaluated using non-parametric ROC analyses.

Results

A sample of 1675 patients was analyzed. In total, 73.6% of participants had low skeletal muscle mass and 24.1% exhibited delirium. Low skeletal muscle mass and delirium showed an independent association (OR: 1.50; 95% CI 1.09–2.08). In the subsample of patients without a diagnosis of dementia, the inclusion of calf circumference in a model based on age and sex significantly improved its discriminative accuracy [area under the curve (AUC) 0.69 vs 0.57, p < 0.001].

Discussion and conclusion

Low muscle mass is independently associated with delirium. In patients without a previous diagnosis of dementia, calf circumference may help to better identify those who develop delirium.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40520-021-01950-8.

The effects of the COVID-19 pandemic on the treatment of allergic eye diseases

PURPOSE OF REVIEW

To analyze if recommendations given before and during the COVID-19 pandemic are still a valid option for patients suffering of ocular allergy (OA).

RECENT FINDINGS

During the last year many doctors and patients requested suggestions for the treatment of OA patients in COVID-19 time. Most of them were given by phone calls and emails following the recommendations given by Scientific Societies.

SUMMARY

Considering the current multiple problems related to the COVID-19 pandemic, OA has not been considered a priority, even though patients need treatments. Topical antiallergic drugs are still the first option to treat all kind of OA, with the addition of topical corticosteroids in the severe forms of vernal and atopic keratoconjunctivitis (VKC and AKC) even in patients at risk of COVID-19. Topical immunomodulation is still recommended in severe forms of VKC and AKC unless the patient is infected. The number of patients treated with these drugs in our Center was similar than previous years. The risk to have a VKC patient affected by COVID-19 is similar to the general pediatric population but with a lower OR. In 2021, still in COVID-time, the management of OA should follow the previous recommendations with an update due to the risk of infection.

Tear N-glycomics in vernal and atopic keratoconjunctivitis

PURPOSE

Tear fluid N-Glycome from patients affected with vernal (VKC) and atopic keratoconjunctivitis (AKC) was investigated to identify specific changes in tears and to recognize possible glyco-biomarkers.

METHODS

The analysis of the N-glycans was performed using matrix-assisted laser desorption ionization mass spectrometry on single tear samples. Tears from control normal subjects (CTRL), VKC and AKC patients were processed and treated with peptide N-glycosidase F (PNGase F) to deglycosylate N-glycoproteins. Released N-glycans were purified, permethylated, and analyzed by matrix-assisted laser desorption/ionization-time of flight mass spectrometry and tandem mass spectrometry (MALDI-TOF MS and MALDI-TOF MS/MS).

RESULTS

More than 150 complex N-glycans, including highly fucosylated biantennary, triantennary, tetra-antennary, and bisecting species, were observed in our spectra. Three distinct patterns for CTRL, VKC, and AKC patients were identified in terms of relative intensities for some N-glycans structures. Major variations involved bisecting and hyperfucosylated glycoforms. The most intense ions were associated with species at m/z 1907.0 (asialo, agalacto, bisected, biantennary structure-NGA2B) in CTRL MS profiles, at m/z 2605.3 and 2966.5 in VKC, and at m/z 2792.4 in AKC corresponding to a well-known biantennary, disialylated N-glycan. Several peaks were associated with structures bearing one or two Lewis X epitopes. Structures were confirmed by MS/MS analysis. Quantitative differences among the three groups were statistically significant.

CONCLUSIONS

Tear MS profiles are rich in specific glycoforms, particularly those with a high fucosylation degree, indicating both core and peripheral decoration. Tear N-glycome analysis provided important information for a better comprehension of VKC and AKC alterations at the molecular level.

Allergy and Dry Eye Disease

Ocular allergy (OA) and dry eye disease (DED) are the most common ocular surface disorders with a potential severe impact on the patient's quality of life. OA and DED may coexist and have a significant clinical overlap. Therefore, clinical features commonly believed to be distinctive of OA or DED may be sometimes insufficient for a differential diagnosis. Alterations of the tear film, epithelial barrier, and corneal innervation are described in OA and can pave the way to DED. Conversely, DED may facilitate or worsen allergic reactions in predisposed (atopic) patients. For these reasons, OA and DED should be considered as reciprocal predisposing conditions that share ocular surface inflammation as a common background.

Open mini-incision vs laparoscopic appendectomy A retrospective single Centre study

INTRODUCTION

Laparoscopy appendectomy (LA) is the most widely used method for the treatment of acute appendicitis (AA). The interest has shifted towards the mini-incision open method (MOA).

MATERIALS AND METHODS

A retrospective study was conducted considering all patients who underwent surgery due to suspected appendicitis from December 2014 to January 2019. The final analysis included 234 patients. The following data were collected: patient age, sex, surgery duration, hospitalization time, wound infections, and mortality.

RESULTS

The average time of surgery was 69.89 minutes in the LA group and 62.17 minutes in the MOA group, while the average time of postoperative hospitalization was respectively 5.579 days and 5.143 days. Wound infections occurred in 2 patients in the LA group and in 3 patients in the MOA group.

CONCLUSION

Laparoscopic appendectomy has a similar operating time, hospitalization time and wound infections as Mini-incision open appendectomy. Therefore,both techniques are to be considered valid.

KEY WORDS

Appendicitis, Laparoscopic appendectomy, Appendectomy, Instrumentation, Open approach.

Role of computed tomography in predicting critical disease in patients with covid-19 pneumonia: A retrospective study using a semiautomatic quantitative method

Background

So far, only a few studies evaluated the correlation between CT features and clinical outcome in patients with COVID-19 pneumonia.

Purpose

To evaluate CT ability in differentiating critically ill patients requiring invasive ventilation from patients with less severe disease.

Methods

We retrospectively collected data from patients admitted to our institution for COVID-19 pneumonia between March 5th-24th. Patients were considered critically ill or non-critically ill, depending on the need for mechanical ventilation. CT images from both groups were analyzed for the assessment of qualitative features and disease extension, using a quantitative semiautomatic method. We evaluated the differences between the two groups for clinical, laboratory and CT data. Analyses were conducted on a per-protocol basis.

Results

189 patients were analyzed. PaO₂/FIO₂ ratio and oxygen saturation (SaO₂) were decreased in critically ill patients. At CT, mixed pattern (ground glass opacities (GGO) and consolidation) and GGO alone were more frequent respectively in critically ill and in non-critically ill patients (p < 0.05). Lung volume involvement was significantly higher in critically ill patients (38.5 % vs. 5.8 %, p < 0.05). A cut-off of 23.0 % of lung involvement showed 96 % sensitivity and 96 % specificity in distinguishing critically ill patients from patients with less severe disease. The fraction of involved lung was related to lactate dehydrogenase (LDH) levels, PaO₂/FIO₂ ratio and SaO₂ (p < 0.05).

Conclusion

Lung disease extension, assessed using quantitative CT, has a significant relationship with clinical severity and may predict the need for invasive ventilation in patients with COVID-19.

High-intensity focused ultrasound for prostate cancer

High-intensity focused ultrasound (HIFU) is a noninvasive procedure that has shown promising results in a wide range of malignant and nonmalignant conditions, including localized prostate cancer (PCa). This review aims to describe the application of HIFU in the management of patients with PCa, explaining its basic therapeutic principles, going through the main phases during aHIFU session, and providing an overview of the main available pieces of evidence from literature. HIFU treatment for prostate cancer is increasingly performed with high success and safety. MR guidance (MR-guided HIFU) has the advantage of real-time intraprocedural thermometric feedback that ensures that the whole region of interest has been covered by critical thermal damage (and that all surrounding healthy tissues have been spared). The absence of comparative long-term trials prevents HIFU from being considered as afirst choice for the treatment of patients with PCa.

Ocular Surface Expression of SARS-CoV-2 Receptors

PURPOSE

The spike proteins of SARS-CoV-2 interact with ACE2 or basigin/CD147 receptors, regulating human-to-human transmissions of COVID-19 together with serine protease TMPRSS2. The expression of these receptors on the ocular surface is unknown.

MATERIAL AND METHODS

Gene expression of SARS-CoV-2 receptors was investigated in conjunctival epithelial cell samples and in ex-vivo cornea samples using microarray or transcriptome sequencing.

RESULTS

ACE2 is expressed in conjunctival samples at a low level, while BSG and TMPRSS2 are expressed at intermediate levels in both conjunctiva and cornea. Other receptors such as ANPEP, AGTR2 are expressed at low level in the conjunctiva. Two RNA editing enzymes involved in antiviral responses, APOBEC3A, and ADAR-1 were also highly expressed.

CONCLUSIONS

The ocular surface may represent an entry point for the SARS-CoV-2 in the human body. The conjunctiva and the cornea can adopt antiviral countermeasures which may explain the low prevalence of eye involvement.

Cationic Emulsion-Based Artificial Tears as a Mimic of Functional Healthy Tear Film for Restoration of Ocular Surface Homeostasis in Dry Eye Disease

Dry eye disease (DED) is a complex multifactorial disease that affects an increasing number of patients worldwide. Close to 30% of the population has experienced dry eye (DE) symptoms and presented with some signs of the disease during their lifetime. The significant heterogeneity in the medical background of patients with DEs and in their sensitivity to symptoms renders a clear understanding of DED complicated. It has become evident over the past few years that DED results from an impairment of the ocular surface homeostasis. Hence, a holistic treatment approach that concomitantly addresses the different mechanisms that result in the destabilization of the tear film (TF) and the ocular surface would be appropriate. The goal of the present review is to compile the different types of scientific evidence (from in silico modeling to clinical trials) that help explain the mechanism of action of cationic emulsion (CE)-based eye drop technology for the treatment of both the signs and the symptoms of DED. These CE-based artificial tear (AT) eye drops designed to mimic, from a functional point of view, a healthy TF contribute to the restoration of a healthy ocular surface environment and TF that leads to a better management of DE patients. The CE-based AT eye drops help restore the ocular surface homeostasis in patients who have unstable TF or no tears.

The epitranscriptomic writer ALKBH8 drives tolerance and protects mouse lungs from the environmental pollutant naphthalene

The epitranscriptomic writer Alkylation Repair Homolog 8 (ALKBH8) is a transfer RNA (tRNA) methyltransferase that modifies the wobble uridine of selenocysteine tRNA to promote the specialized translation of selenoproteins. Using Alkbh8 deficient (Alkbh8^def) mice, we have investigated the importance of epitranscriptomic systems in the response to naphthalene, an abundant polycyclic aromatic hydrocarbon and environmental toxicant. We performed basal lung analysis and naphthalene exposure studies using wild type (WT), Alkbh8^{de f} and Cyp2abfgs-null mice, the latter of which lack the cytochrome P450 enzymes required for naphthalene bioactivation. Under basal conditions, lungs from Alkbh8^def mice have increased markers of oxidative stress and decreased thioredoxin reductase protein levels, and have reprogrammed gene expression to differentially regulate stress response transcripts. Alkbh8^def mice are more sensitive to naphthalene induced death than WT, showing higher susceptibility to lung damage at the cellular and molecular levels. Further, WT mice develop a tolerance to naphthalene after 3 days, defined as resistance to a high challenging dose after repeated exposures, which is absent in Alkbh8^def mice. We conclude that the epitranscriptomic writer ALKBH8 plays a protective role against naphthalene-induced lung dysfunction and promotes naphthalene tolerance. Our work provides an early example of how epitranscriptomic systems can regulate the response to environmental stress in vivo.

Clinical efficacy assessment in severe vernal keratoconjunctivitis: preliminary validation of a new penalties-adjusted corneal fluorescein staining score

Introduction and objective: Vernal keratoconjunctivitis (VKC) is a rare allergic eye condition that occurs in children and is characterised by a combination of debilitating symptoms. Repeated use of topical corticosteroid rescue therapy is often necessary in severe forms. This study aims to assess the validity of a new composite endpoint: the penalties-adjusted corneal staining score (PACS-S) proposed as primary endpoint in VEKTIS trial evaluating the efficacy of a new corticosteroid-sparing treatment, VERKAZIA® (ciclosporin 1 mg/ml eye drops), in severe VKC patients. Methodology: This research comprised a systematic literature review to identify efficacy endpoints being proposed in clinical trials for pediatric patients with severe VKC, followed by a remote expert advisory board assessing the validity of the PACS-S. Results: While no agreed or validated endpoint for assessing efficacy in VKC was identified when VEKTIS trial started, the experts' board acknowledged a high face validity of PACS-S as a subjective integrated measure matching the current clinical practice. A fair external validity was considered with regards to VEKTIS trial secondary endpoints. Conclusion: PACS-S appears to be a reliable, valid and clinically meaningful primary endpoint that allows significant improvement over existing endpoints in severe VKC trials. Additional research is needed to validate this endpoint.

Twelve-Month Results of Cyclosporine A Cationic Emulsion in a Randomized Study in Patients With Pediatric Vernal Keratoconjunctivitis

PURPOSE

To assess the safety and efficacy of cyclosporine A cationic emulsion (CsA CE) 0.1% eye drops in pediatric patients with severe active vernal keratoconjunctivitis (VKC).

DESIGN

Multicenter, double-masked, randomized controlled trial 8-month safety analysis.

METHODS

Of 169 patients (age range, 4-17 years) initially randomized in the 4-month VErnal KeratoconjunctiviTIs Study (VEKTIS), 142 entered the 8-month follow-up period during which CsA CE patients remained on their original regimen (CsA CE 4 times daily [QID, high-dose] or CsA CE twice daily [BID, low-dose] + vehicle BID) and vehicle patients were allocated to one of these 2 active regimens. Main outcome measures were safety, including treatment-emergent adverse events, and efficacy, including corneal fluorescein staining (CFS) score.

RESULTS

Improvements in CFS score, rescue medication use, key VKC symptoms (photophobia, tearing, itching, and mucous discharge), and quality of life (QoL) assessed by QUICK questionnaire observed with CsA CE compared with vehicle during the 4-month evaluation period remained stable during the 8-month follow-up period, with the high-dose regimen continuing to provide greater benefits in most efficacy measures. CsA CE was well tolerated. Treatment-related treatment-emergent adverse events during the 12-month study were reported in 15 (20.8%) and 11 (15.7%) of the CsA CE high-dose and low-dose patients, respectively, most commonly instillation site pain (13.9% and 7.1%, respectively). Laboratory data, vital signs, slit lamp examination, best-corrected distance visual acuity, and intraocular pressure raised no safety concerns.

CONCLUSIONS

Improvements in keratitis, symptoms, and QoL achieved after CsA CE treatment for 4 months remained stable over the 8-month follow-up period. CsA continued to maintain a favorable safety profile.

ICON: Diagnosis and management of allergic conjunctivitis

Ocular allergy (OA), interchangeably known as allergic conjunctivitis, is a common immunological hypersensitivity disorder affecting up to 40% of the population. Ocular allergy has been increasing in frequency, with symptoms of itching, redness, and swelling that significantly impacts an individual's quality of life (QOL). Ocular allergy is an often underdiagnosed and undertreated health problem, because only 10% of patients with OA symptoms seek medical attention, whereas most patients manage with over-the-counter medications and complementary nonpharmacological remedies. The clinical course, duration, severity, and co-morbidities are varied and depend, in part, on the specific ocular tissues that are affected and on immunologic mechanism(s) involved, both local and systemic. It is frequently associated with allergic rhinitis (commonly recognized as allergic rhino conjunctivitis), and with other allergic comorbidities. The predominance of self-management increases the risk of suboptimal therapy that leads to recurrent exacerbations and the potential for development of more chronic conditions that can lead to corneal complications and interference with the visual axis. Multiple, often co-existing causes are seen, and a broad differential diagnosis for OA, increasing the difficulty of arriving at the correct diagnosis(es). Ocular allergy commonly overlaps with other anterior ocular disease disorders, including infectious disorders and dry eye syndromes. Therefore, successful management includes overcoming the challenges of underdiagnosis and even misdiagnosis by a better understanding of the subtleties of an in-depth patient history, ophthalmologic examination techniques, and diagnostic procedures, which are of paramount importance in making an accurate diagnosis of OA. Appropriate cross-referral between specialists (allergists and eyecare specialists) would maximize patient care and outcomes. This would significantly improve OA management and overcome the unmet needs in global health.

Loss of epitranscriptomic control of selenocysteine utilization engages senescence and mitochondrial reprogramming☆

Critically important to the maintenance of the glutathione (GSH) redox cycle are the activities of many selenocysteine-containing GSH metabolizing enzymes whose translation is controlled by the epitranscriptomic writer alkylation repair homolog 8 (ALKBH8). ALKBH8 is a tRNA methyltransferase that methylates the wobble uridine of specific tRNAs to regulate the synthesis of selenoproteins. Here we demonstrate that a deficiency in the writer ALKBH8 (Alkbh8^def), alters selenoprotein levels and engages senescence, regulates stress response genes and promotes mitochondrial reprogramming. Alkbh8^def mouse embryonic fibroblasts (MEFs) increase many hallmarks of senescence, including senescence associated β-galactosidase, heterocromatic foci, the cyclin dependent kinase inhibitor p16^Ink4a, markers of mitochondrial dynamics as well as the senescence associated secretory phenotype (SASP). Alkbh8^def cells also acquire a stress resistance phenotype that is accompanied by an increase in a number redox-modifying transcripts. In addition, Alkbh8^def MEFs undergo a metabolic shift that is highlighted by a striking increase in the level of uncoupling protein 2 (UCP2) which enhances oxygen consumption and promotes a reliance on glycolytic metabolism. Finally, we have shown that the Alkbh8 deficiency can be exploited and corresponding MEFs are killed by glycolytic inhibition. Our work demonstrates that defects in an epitransciptomic writer promote senescence and mitochondrial reprogramming and unveils a novel adaptive mechanism for coping with defects in selenocysteine utilization.

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Deficiencies in selenocysteine utilization engages cellular senescence and the senescence associated secretory phenotype.

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Alkbh8 deficiency promotes mitochondrial elongation, increased oxygen consumption and a reliance on glycolytic metabolism.

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Cellular adaptions to Alkbh8 deficiency confer stress resistance.

Epitranscriptomic systems regulate the translation of reactive oxygen species detoxifying and disease linked selenoproteins

Here we highlight the role of epitranscriptomic systems in post-transcriptional regulation, with a specific focus on RNA modifying writers required for the incorporation of the 21st amino acid selenocysteine during translation, and the pathologies linked to epitranscriptomic and selenoprotein defects. Epitranscriptomic marks in the form of enzyme-catalyzed modifications to RNA have been shown to be important signals regulating translation, with defects linked to altered development, intellectual impairment, and cancer. Modifications to rRNA, mRNA and tRNA can affect their structure and function, while the levels of these dynamic tRNA-specific epitranscriptomic marks are stress-regulated to control translation. The tRNA for selenocysteine contains five distinct epitranscriptomic marks and the ALKBH8 writer for the wobble uridine (U) has been shown to be vital for the translation of the glutathione peroxidase (GPX) and thioredoxin reductase (TRXR) family of selenoproteins. The reactive oxygen species (ROS) detoxifying selenocysteine containing proteins are a prime examples of how specialized translation can be regulated by specific tRNA modifications working in conjunction with distinct codon usage patterns, RNA binding proteins and specific 3' untranslated region (UTR) signals. We highlight the important role of selenoproteins in detoxifying ROS and provide details on how epitranscriptomic marks and selenoproteins can play key roles in and maintaining mitochondrial function and preventing disease.

Neutrophils cause obstruction of eyelid sebaceous glands in inflammatory eye disease in mice

Meibomian glands (MGs) are sebaceous glands of the eyelid margin that secrete lipids needed to avert tear evaporation and to help maintain ocular surface homeostasis. Obstruction of MGs or other forms of MG dysfunction can promote chronic diseases of the ocular surface. Although chronic eyelid inflammation, such as allergic eye disease, is an associated risk factor for obstructive MG dysfunction, it is not clear whether inflammatory processes contribute to the pathophysiology of MG obstruction. We show that polymorphonuclear neutrophils (PMNs) promoted MG obstruction in a chronic inflammatory model of allergic eye disease in mice. Analysis of leukocytes in tears of patients with MG dysfunction showed an increase in PMN numbers compared to healthy subjects. Moreover, PMN numbers in tears positively correlated with clinical severity of MG dysfunction. Our findings point to a role for PMNs in the pathogenesis and progression of MG dysfunction.

Management of ocular allergy

The treatment and management of ocular allergy (OA) remain a major concern for different specialties, including allergists, ophthalmologists, primary care physicians, rhinologists, pediatricians, dermatologists, clinical immunologists, and pharmacists. We performed a systematic review of all relevant publications in MEDLINE, Scopus, and Web Science including systematic reviews and meta-analysis. Publications were considered relevant if they addressed treatments, or management strategies of OA. A further wider systematic literature search was performed if no evidence or good quality evidence was found. There are effective drugs for the treatment of OA; however, there is a lack an optimal treatment for the perennial and severe forms. Topical antihistamines, mast cell stabilizers, or double-action drugs are the first choice of treatment. All of them are effective in reducing signs and symptoms of OA. The safety and optimal dosing regimen of the most effective topical anti-inflammatory drugs, corticosteroids, are still a major concern. Topical calcineurin inhibitors may be used in steroid-dependent/resistant cases of severe allergic keratoconjunctivitis. Allergen-specific immunotherapy may be considered in cases of failure of first-line treatments or to modify the natural course of OA disease. Based on the current wealth of publications and on the collective experience, recommendations on management of OA have been proposed.

Cornea verticillata in Fabry disease: a comparative study between slit-lamp examination and in vivo corneal confocal microscopy

Purpose

To compare the diagnostic power of slit-lamp examination with the in vivo corneal confocal microscopy (IVCM) as the gold standard in assessing the presence of corneal epithelial deposits in patients with Fabry disease (FD).

Methods

Fourteen patients with FD (4 males, 10 females; mean age, 46.8 years) and eight healthy controls (4 males, 4 females; mean age, 36.75 years) were included. All subjects underwent slit-lamp examination and IVCM of both central and peripheral corneal quadrants with the Heidelberg Retina Tomograph-III in combination with the Rostock Cornea Module.

Results

In patients with FD, 9 of 28 eyes (32%) showed the presence of cornea verticillata at the slit-lamp examination and 25 eyes (89%) showed the presence of epithelial hyper-reflective deposits at the IVCM. Of the 19 eyes negative at the slit-lamp examination, 16 eyes showed the presence of epithelial deposits at the IVCM. Compared with controls, patients with FD had a significantly reduced number, density and length of nerve fibres at the level of corneal sub-basal nerve plexus, but a significantly higher grade of fibres tortuosity.

Conclusions

The slit-lamp examination has a limited diagnostic power in the detection of epithelial deposits in patients with FD when compared with the IVCM. In fact, the slit-lamp examination suffers from a high number of false negative results and, consequently, from a low negative predictive value (16%). IVCM allows the detection of corneal microstructural changes in patients with FD and may represent a reliable tool for the early diagnosis and follow-up of the disease.

Efficacy and safety of 0.1% ciclosporin A cationic emulsion in dry eye disease: a pooled analysis of two double-masked, randomised, vehicle-controlled phase III clinical studies

BACKGROUND/AIM

To assess the treatment effect of 0.1% ciclosporin A cationic emulsion (CsA CE) versus vehicle on signs/symptoms of dry eye disease (DED) in various subgroups (moderate-to-severe DED/severe DED/Sjögren's syndrome (SS)/SS with severe DED).

METHODS

Pooled data were analysed from two similar phase III studies: SICCANOVE (moderate-to-severe DED) and SANSIKA (severe DED with severe keratitis). In both studies, patients aged ≥18 years received CsA CE 0.1% (n=395) or vehicle (n=339) once daily for 6 months. A composite responder efficacy endpoint (corneal fluorescein staining-Ocular Surface Disease Index (CFS-OSDI) at month 6) was used to evaluate the efficacy of CsA CE in alleviating signs/symptoms of DED (response defined as improvement of ≥2 grades in CFS and ≥30% in OSDI (baseline to month 6)). Human leucocyte antigen-DR (HLA-DR) conjunctival expression was used as a biomarker of ocular surface inflammation.

RESULTS

CsA CE-treated patients were significantly more likely to be CFS-OSDI responders than vehicle-treated patients in the overall (OR 1.66, 95% CI 1.11 to 2.50; P=0.015), severe DED (1.80, 1.04 to 3.19; P=0.038) and SS with severe DED (3.37, 1.20 to 11.19; P=0.030) populations. The difference was not significant for CsA CE versus vehicle for the overall Sjögren's population (OR 1.77, CI 0.89 to 3.66; P=0.109). CsA CE also significantly reduced median HLA-DR expression versus vehicle at 6 months (P=0.002).

CONCLUSION

Pooled phase III data indicate CsA CE produced significant improvement in signs/symptoms versus vehicle in patients with moderate-to-severe DED (especially in those with severe keratitis), including patients with SS with severe DED.

Persistence of Efficacy of 0.1% Cyclosporin A Cationic Emulsion in Subjects with Severe Keratitis Due to Dry Eye Disease: A Nonrandomized, Open-label Extension of the SANSIKA Study

PURPOSE

Results from a 6-month double-masked and a 6-month open-label study (SANSIKA) established the efficacy and safety of once-daily 0.1% cyclosporin A cationic emulsion (CsA CE) in severe keratitis due to dry eye disease (DED). This article presents results from the Post-SANSIKA study, a 24-month extension of SANSIKA assessing the sustained efficacy of CsA CE after treatment discontinuation.

METHODS

Time to relapse (corneal fluorescein staining [CFS] score ≥4 [modified Oxford scale]) was assessed after treatment discontinuation in patients from the SANSIKA study who had CFS improvement from a score of 4 to ≤2 after 6 or 12 months of treatment with CsA CE.

FINDINGS

Of 62 patients who achieved a CFS score ≤2 at the end of the SANSIKA study, 38 did not relapse and 24 (39%) relapsed during the 24-month period after CsA CE discontinuation; the latter (relapse) group comprised 35% of patients initially treated with CsA CE for 12 months in SANSIKA versus 47% of those treated for 6 months only. Patients spent the most time during the extension study at CFS scores of 1 or 2 (median duration of 8.5 weeks and 14.7 weeks per year, respectively), indicating marked improvement, and less time at scores of 3, 4, or 5 (median time, 2.0 weeks, 0 weeks, and 0 weeks per year). Of 23 patients eligible for safety analysis (ie, patients who received the study treatment at least once), 12 (52.2%) reported a total of 26 ocular adverse events (AEs). Among these, 5 ocular AEs, reported in 5 patients (21.7%), were considered related to study treatment: 3 events of mild instillation site pain in 3 patients (13.0%) and eye discharge and foreign body sensation, each reported in 1 patient (4.3%). Only 1 systemic AE (nasal congestion), reported in 1 patient (4.3%), was considered related to study treatment. None of the AEs led to treatment discontinuation.

IMPLICATIONS

The majority of patients who discontinued CsA CE after experiencing DED improvement in the SANSIKA study did not experience a relapse in this 24-month follow-up study; these patients spent the most time at CFS scores consistent with marked improvement. CsA CE had a favorable safety/tolerability profile over 2 years. Treatment for up to 12 months with CsA CE provides sustained improvements in patients with severe keratitis due to DED. EudraCT registration no. 2012-002066-12.

Efficacy and Tolerability of Ketotifen in the Treatment Of Seasonal Allergic Conjunctivitis: Comparison between Ketotifen 0.025% and 0.05% Eye Drops

Purpose: To study the tolerability and efficacy of two formulations of topical ketotifen ophthalmic solutions for the treatment of seasonal allergic conjunctivitis (SAC).Methods: 81 active SAC patients were treated with either ketotifen 0.025% or 0.05% eye drops for 3 weeks. Allergic signs and symptoms were evaluated at baseline (V0), after 7 (V1) and 21 days (V2). Drugs tolerability and ratings of global efficacy were recorded.Results: Both concentrations of ketotifen were highly effective. The total signs and symptoms scores (TSSS) were significantly better reduced by ketotifen 0.025% compared to 0.05% at both V1 and V2 (p < 0.001). Ketotifen 0.025% was better tolerated than 0.05% at the first instillation and at days 2, 4, and 6 (p < 0.0001), and had a better responder rate (p < 0.001) according to the patient's and investigator's assessments.Conclusions: Ketotifen 0.025% was more effective and better tolerated than 0.05% in SAC.

Intravitreal Sirolimus for the Treatment of Noninfectious Uveitis: Evolution through Preclinical and Clinical Studies

In recent decades, the treatment paradigm for noninfectious intermediate uveitis, posterior uveitis, and panuveitis, a group of intraocular inflammatory diseases, has included systemic and local (periocular or intraocular) corticosteroids, biologics, and other steroid-sparing immunomodulatory therapy agents. Recently, an intravitreal formulation of sirolimus, an immunosuppressant that inhibits the mammalian target of rapamycin, a key regulator of cell growth in the immune system, was developed. On the basis of this mechanism and the local method of delivery, it was hypothesized that intravitreal sirolimus can improve ocular inflammation in patients with noninfectious intermediate uveitis, posterior uveitis, and panuveitis, with minimal systemic exposure and systemic adverse events (AEs). This review summarizes the pharmacokinetics, efficacy, and safety results of intravitreal sirolimus from 3 preclinical studies and 4 phase 1-3 clinical studies. Preclinical studies in rabbits showed that 22 to 220 μg intravitreal sirolimus results in sustained release of sirolimus in the vitreous for 2 months or more, with systemic concentrations below the threshold for systemic immunosuppression (approximately 8 ng/ml). Subsequently, 2 phase 1 studies (n = 50 and n = 30) established that intravitreal sirolimus improves ocular inflammation in humans. Further investigation in phase 2 and 3 studies (n = 24 and n = 347, respectively) suggested that 440 μg has the best benefit-to-risk profile. In the phase 3 study, the proportion of patients who showed complete resolution of ocular inflammation at month 5 was significantly higher in the 440-μg group than in the 44-μg group (22.8% vs. 10.3%; P = 0.025, Fisher exact test). In addition, 47 of 69 patients (68.1%) who were treated with systemic corticosteroids at baseline discontinued corticosteroid use at month 5. No sirolimus-related systemic AEs were reported in phase 1-3 studies. Collectively, these preclinical and clinical study data of intravitreal sirolimus support the therapeutic rationale of treating noninfectious uveitis with a local mammalian target of rapamycin inhibitor and suggest that 440 μg intravitreal sirolimus has the potential to be an effective and well-tolerated anti-inflammatory and corticosteroid-sparing treatment for noninfectious intermediate uveitis, posterior uveitis, and panuveitis.