The gut microbiome and HLA-B27-associated anterior uveitis: a case-control study.

BACKGROUND: The human gut microbiome (GM) is involved in inflammation and immune response regulation. Dysbiosis, an imbalance in this ecosystem, facilitates pathogenic invasion, disrupts immune equilibrium, and potentially triggers diseases including various human leucocyte antigen (HLA)-B27-associated autoinflammatory and autoimmune diseases such as inflammatory bowel disease (IBD) and spondyloarthropathy (SpA). This study assesses compositional and functional alterations of the GM in patients with HLA-B27-associated non-infectious anterior uveitis (AU) compared to healthy controls. METHODS: The gut metagenomes of 20 patients with HLA-B27-associated non-infectious AU, 21 age- and sex-matched HLA-B27-negative controls, and 6 HLA-B27-positive healthy controls without a history of AU were sequenced using the Illumina NovaSeq 6000 platform for whole metagenome shotgun sequencing. To identify taxonomic and functional features with significantly different relative abundances between groups and to identify associations with clinical metadata, the multivariate association by linear models (MaAsLin) R package was applied. RESULTS: Significantly higher levels of the Eubacterium ramulus species were found in HLA-B27-negative controls (p = 0.0085, Mann-Whitney U-test). No significant differences in microbial composition were observed at all other taxonomic levels. Functionally, the lipid IVA biosynthesis pathway was upregulated in patients (p < 0.0001, Mann-Whitney U-test). A subgroup analysis comparing patients with an active non-infectious AU to their age- and sex-matched HLA-B27-negative controls, showed an increase of the species Phocaeicola vulgatus in active AU (p = 0.0530, Mann-Whitney U-test). An additional analysis comparing AU patients to age- and sex-matched HLA-B27-positive controls, showed an increase of the species Bacteroides caccae in controls (p = 0.0022, Mann-Whitney U-test). CONCLUSION: In our cohort, non-infectious AU development is associated with compositional and functional alterations of the GM. Further research is needed to assess the causality of these associations, offering potentially novel therapeutic strategies.

Investigation of the acute pathogenesis of spondyloarthritis/HLA-B27-associated anterior uveitis based on genome-wide association analysis and single-cell transcriptomics.

BACKGROUND: Patients with spondyloarthritis (SpA)/HLA-B27-associated acute anterior uveitis (AAU) experience recurring acute flares, which pose significant visual and financial challenges. Despite established links between SpA and HLA-B27-associated AAU, the exact mechanism involved remains unclear, and further understanding is needed for effective prevention and treatment. METHODS: To investigate the acute pathogenesis of SpA/HLA-B27-associated AAU, Mendelian randomization (MR) and single-cell transcriptomic analyses were employed. The MR incorporated publicly available protein quantitative trait locus data from previous studies, along with genome-wide association study data from public databases. Causal relationships between plasma proteins and anterior uveitis were assessed using two-sample MR. Additionally, colocalization analysis was performed using Bayesian colocalization. Single-cell transcriptome analysis utilized the anterior uveitis dataset from the Gene Expression Omnibus (GEO) database. Dimensionality reduction, clustering, transcription factor analysis, pseudotime analysis, and cell communication analysis were subsequently conducted to explore the underlying mechanisms involved. RESULTS: Mendelian randomization analysis revealed that circulating levels of AIF1 and VARS were significantly associated with a reduced risk of developing SpA/HLA-B27-associated AAU, with AIF1 showing a robust correlation with anterior uveitis onset. Colocalization analysis supported these findings. Single-cell transcriptome analysis showed predominant AIF1 expression in myeloid cells, which was notably lower in the HLA-B27-positive group. Pseudotime analysis revealed dendritic cell terminal positions in differentiation branches, accompanied by gradual decreases in AIF1 expression. Based on cell communication analysis, CD141+CLEC9A+ classic dendritic cells (cDCs) and the APP pathway play crucial roles in cellular communication in the Spa/HLA-B27 group. CONCLUSIONS: AIF1 is essential for the pathogenesis of SpA/HLA-B27-associated AAU. Myeloid cell differentiation into DCs and decreased AIF1 levels are also pivotal in this process.

Genetic variations of IL10 and IL6R genes in acute anterior uveitis in Han Chinese.

BACKGROUND: Several autoimmune disorders have been linked to polymorphisms in IL10 and IL6R genes. This research aimed to study whether single nucleotide polymorphisms (SNPs) in the genes of IL10 and IL6R were associated with acute anterior uveitis (AAU) in Han Chinese. METHODS: Genotyping was carried out by the iPLEX Gold Genotyping Assay. Our study comprised 420 patients with AAU and 918 healthy subjects from Han Chinese. Using the chi-square (χ2) test, alleles and genotypes were analyzed between AAU subjects and healthy controls. RESULTS: All ten SNPs were successfully genotyped and four SNPs (IL10/rs1800871, IL10/rs3021094, IL10/rs2222202, IL6R/rs4845618) exhibited weak associations with AAU, as indicated by their Puncorr values. However, upon applying the Bonferroni correction, there was no significant association between AAU and the control subjects. Additionally, the haplotype analysis of the ten SNPs revealed no association with AAU. CONCLUSION: Our findings suggested that polymorphisms of the tested ten SNPs on the IL10 and IL6R genes did not show any association with the risk of developing AAU among the Han Chinese population.

Retinal and choroidal thickness in fuchs uveitis syndrome: a contralateral eye study.

BACKGROUND: To investigate the subfoveal retinal and choroidal thickness in patients with unilateral Fuchs Uveitis Syndrome (FUS). METHODS: This comparative contralateral study was performed in affected eyes with FUS versus fellow eyes. For each eye parameters such as subfoveal choroidal thickness (SCT), subfoveal choriocapillary thickness (SCCT), central macular thickness (CMT), and central macular volume (CMV) were measured; then the measured values of affected and fellow unaffected eye were compared. RESULTS: Thirty-seven patients (74 eyes) including 19 females (51.4%) with a mean age of 36.9 ± 7.6 years were enrolled. The mean SCT was lower in the affected eyes (344.51 ± 91.67) than in the fellow (375.59 ± 87.33) with adjusting for duration of disease and axial lengths (P < 0.001). The mean SCCT, CMT, and CMV were higher in eyes with FUS than in fellow eyes (P < 0.05). CONCLUSIONS: The result of our study demonstrated that affected eyes in patients with FUS tend to have thinner SCT and thicker SCCT and CMT compared to uninvolved fellow eyes.

Prevalence of anterior uveitis in cases of systemic inflammatory response syndrome in dogs and cats.

OBJECTIVE: To determine the prevalence of anterior uveitis in dogs and cats hospitalized with a diagnosis of systemic inflammatory response syndrome (SIRS). ANIMALS STUDIED: Dogs and cats hospitalized between May 2020 and January 2021 were prospectively included. PROCEDURES: Patients were categorized into two different groups: The first group included patients diagnosed with SIRS, and the second group included patients hospitalized without SIRS as a control group. Daily physical and ophthalmological examinations were conducted during hospitalization. Diagnosis of anterior uveitis was made based on the presence of aqueous flare, low intraocular pressure, and other associated ocular signs such as episcleral injection and miosis. A multinomial logistic regression analysis was conducted to investigate factors associated with SIRS and anterior uveitis development. RESULTS: The study comprised 42 patients with SIRS and 26 patients without SIRS. Among those with SIRS, 38% developed anterior uveitis, whereas only 7.7% of patients without SIRS showed signs of anterior uveitis. The prevalence of uveitis was significantly higher in animals with SIRS compared to those without SIRS (p < .05). CONCLUSION: Anterior uveitis is more prevalent in patients with SIRS than patients without SIRS. Therefore, complete ophthalmic examination is recommended in all patients presenting with this syndrome.

Association of TBX21 gene polymorphisms and acute anterior uveitis risk in a Chinese population: A case-control study.

Copy number variations (CNVs) in TBX21 gene have been reported to be significantly and positively correlated with acute anterior uveitis (AAU). Our study was performed to further determine whether single nucleotide polymorphisms (SNPs) in TBX21 gene confer susceptibility to AAU in a Chinese population. In our case-control study, 420 AAU patients and 918 healthy controls were included. SNP genotyping was conducted via the MassARRAY™ iPLEX Gold platform. Association and haplotype analyses were performed via SPSS 23.0 and SHEsis software. No significant association was observed between two candidate SNPs of TBX21 gene (rs4794067, rs11657479) and susceptibility to AAU (Pc > 0.05). In stratification analysis, the result also showed no significant difference between the HLA-B27 positive AAU patients and non-typed healthy controls. Additionally, no association was detected between TBX21 haplotypes and AAU risk. In conclusion, the polymorphisms rs4794067 and rs11657479 in TBX21 gene did not confer disease susceptibility to AAU in a Chinese population.

Relationship between Helicobacter pylori and undifferentiated non-granulomatous anterior uveitis.

PURPOSE: The relationship of Helicobacter pylori infection with ocular diseases, including anterior uveitis, has been reported. The objective of this study was to determine the presence of anti-H. pylori IgG antibodies in patients with idiopathic non-granulomatous anterior uveitis and compare the results with a control group. METHODS: A prospective, comparative, and cross-sectional study was conducted. Patients with idiopathic granulomatous anterior uveitis and a group of control subjects were included. The presence of anti-H. pylori IgG antibodies was determined. The chi-square test was performed for comparative analysis with GraphPad Prism V5.0 software. RESULTS: Thirty patients with idiopathic non-granulomatous anterior uveitis and 35 control subjects were included. In the determination of anti-H. pylori IgG antibodies, 24 (80%) patients and 19 (54%) control subjects were positive. A significant difference (p = 0.0263) was found between the groups and an odds ratio (OR) of 3.37. CONCLUSIONS: A direct relationship was found between the presence of anti-H. pylori IgG antibodies and idiopathic non-granulomatous anterior uveitis. An association can be established between idiopathic non-granulomatous anterior uveitis and H. pylori infection, without this being a causal or physiopathogenic relationship.

Immunity status and expression of molecular markers (ICAM-1, CD5, CD25, CD95) on lymphocytes of patients with recurrent anterior uveitis complicated by macular edema.

BACKGROUND: Treatment of macular edema in uveitis is a key goal of treatment, because this complication remains a potential therapeutic problem for specialists. MATERIAL AND METHODS: Examination was carried out in 1-2 groups - 50 persons with uncomplicated recurrent anterior uveitis (AU) in the stage of relapse or remission - and 3-4 groups - 26 persons with recurrent AU complicated by uveitic macular edema (UME) in the stage of relapse or remission of AU. Control group - 27 healthy volunteers. All patients underwent an ophthalmologic examination, using OCT (Spectralis HRA + OCT (Heidelberg Engineering)). The state of cellular and humoral immunity and the expression of activation markers on blood lymphocytes in all patients were assessed. An immunohistocytochemical analysis using monoclonal antibodies (the peroxidase-anti-peroxidase method) was employed to assess the expression of lymphocyte activation markers. The monoclonal antibody panel (MCAP) for immunophenotyping included antibodies reacting with CD5, CD54 (ICAM-1), CD25, and CD95 (FAS) antigens. Immunophenotyping was performed using immunohistochemistry. RESULTS: In the patients with AU + UME, the parameters of the T-cell link of the immune response were increased and the parameters of humoral immunity (CD19, IgA, IgG) were decreased in comparison with the uncomplicated AU patients. The absolute and relative numbers of natural killer cells in the peripheral blood were higher, and the relative numbers of phagocytic neutrophils were lower in the group of anterior uveitis with UME than in uncomplicated AU. The absolute and relative expression levels of ICAM-1 (CD54) and the absolute expression level of CD5 on peripheral blood lymphocytes were increased in relapse at patients with AU + UME compared with uncomplicated AU. The expression levels of CD25 and CD95 were not different in these groups. CONCLUSION: Activation of cellular immunity markers ICAM-1 and CD5 seems to play a role in uveitic macular edema. The expression levels of CD25 and CD95 were not significantly different in these groups.

Acute exacerbation of ocular graft-versus-host disease and anterior uveitis after COVID-19 vaccination.

BACKGROUND: To report a case of simultaneous occurrence of acute exacerbation of ocular graft-versus-host disease (GVHD) and anterior uveitis following coronavirus disease 2019 (COVID-19) vaccination. CASE PRESENTATION: A 60-year-old man with primary myelofibrosis and GVHD after receiving allogeneic hematopoietic stem cell transplantation (HSCT), developed acute exacerbation of ocular GVHD and anterior uveitis after receiving first dose of COVID-19 vaccine. The patient developed erythema of the eyelids, conjunctival hyperemia, superficial punctate keratopathy, and prominent anterior chamber inflammation in both eyes. The ocular GVHD and anterior uveitis were managed with mainly topical corticosteroids, antibiotics, lubricants, and systemic corticosteroids, but were difficult to control. Intravitreal injection of dexamethasone was administered, and the inflammation gradually subsided 6 months after the onset of initial symptoms. CONCLUSIONS: Clinicians should be aware of rare refractory anterior uveitis and acute exacerbation of ocular GVHD after COVID-19 vaccination in patients undergoing HSCT. Early diagnosis and aggressive treatment should be considered to reduce the likelihood of severe complications.

Cidofovir-induced anterior uveitis in an allogeneic stem cell transplant recipient.

Anterior uveitis is a reported complication of intravenous cidofovir, almost exclusively described in human immunodeficiency virus (HIV) infected patients treated for cytomegalovirus retinitis. In this study, we report the case of an allogeneic stem cell transplant recipient with significant visual impairment and hypotony following administration of high-dose intravenous cidofovir for hemorrhagic cystitis due to BK virus.

Iridian anterior segment OCT in rubella uveitis syndrome and cytomegalovirus anterior uveitis: a comparative study.

PURPOSE: To compare iris affectation in cytomegalovirus anterior uveitis (CMVAU), rubella virus-associated uveitis (RVU), and healthy contralateral eyes, using swept-source anterior segment optical coherence tomography (SS-AS-OCT). MATERIALS AND METHODS: A comparative, transversal, retrospective study examining 60 eyes from 30 patients-18 eyes (17 patients) with CMVAU, 14 eyes (13 patients) with RVU, and 28 healthy eyes-was performed. Six-millimeter cross-sectional SS-AS-OCT B-scans were obtained in each iris quadrant. Images were exported to ImageJ®. Qualitative and quantitative analyses were done: stromal thickness (ST), smooth index (SI), and optical density (OD) of pigment epithelium. Comparisons between measurements and clinical-demographic parameters were performed using SPSS®. RESULTS: Qualitative analysis showed extensive damage in iris stroma but was unable to differentiate between both uveitis. RVU eyes had a lower mean ST (315.72 µm ± 42.4) compared to those with CMVAU (348.6 µm ± 46) (p = 0.047) and a lower ST in the upper (338.9 µm ± 38.52)/(386.25 µm ± 47.2) (p = 0.005) and temporal (281.5 µm ± 57.3)/(326.43 µm ± 62.3) (p = 0.016) quadrants. Mean (0.94 ± 0.02)/(0.9 ± 0.03) (p = 0.001), temporal (0.94 ± 0.02)/(0.89 ± 0.03) (p < 0.001), and nasal SI (0.094 ± 0.02)/(0.9 ± 0.04) (p = 0.005) were higher in RVU. OD was similar in both uveitis. In healthy eyes, mean ST (376.8 µm ± 39.7) was higher and mean SI was lower (0.87 ± 0.04) than in RVU (p < 0.001) and CMVAU eyes (p = 0.032). Mean OD was higher in healthy eyes (911 ± 130) than in CMVAU eyes (800 ± 200) (p = 0.037). CONCLUSIONS: The quantitative analysis of the SS-AS-OCT iris images allows for the differentiation between healthy eyes and those with CMVAU and RVU, as well as between both uveitis.

Uveitis and nail psoriasis in a patient without articular involvement: a case report.

BACKGROUND: This study aimed to report a case of bilateral anterior non-granulomatous chronic non-infectious uveitis associated with isolated nail psoriasis without articular involvement. CASE PRESENTATION: A 55-year-old man with a history of open-angle glaucoma was referred to our uveitis and ocular immunology center with intraocular inflammation concordant with chronic non-infectious bilateral anterior non-granulomatous uveitis. At presentation, he had moderate inflammation in the anterior chamber bilaterally and lesions characteristic of nail psoriasis. Nail psoriasis was later confirmed by nail ultrasonography performed by a radiologist who specialized in psoriasis. Appropriate clinical and paraclinical assessments were conducted, ruling out all other possible causes of uveitis. The patient required dual systemic immunomodulatory therapy with methotrexate and adalimumab, topical anti-inflammatory drugs (steroidal and non-steroidal), and anti-glaucoma therapy to achieve satisfactory inflammatory and ocular pressure control. DISCUSSION AND CONCLUSIONS: This is the first report of non-infectious uveitis associated with nail compromise in a patient without other manifestations of psoriasis. Despite reports on the relationship between psoriatic disease and uveitis, there is insufficient information on clinical phenotypes associated with uveitis that could lead to later diagnosis and treatment of associated intraocular inflammation. Clinicians should be aware of all subtypes of psoriasis that increases a risk of developing uveitis in these patients.

Herpetic uveitis caused by herpes simplex virus after cataract surgery in a patient without prior viral keratitis or uveitis: a case report.

BACKGROUND: To report a case of herpetic uveitis caused by herpes simplex virus after cataract surgery in a patient without prior viral keratitis or uveitis. CASE PRESENTATION: A 70-year-old female was referred to our clinic with a 16-day history of acute blurry vision with painful redness in the right eye. She accepted cataract surgery for the right eye ten days before initial of ocular symptoms. There was significant inflammation in anterior chamber of the right eye. Retina exam showed moderate dense vitreous opacity but not necrotic or focal retinal lesion in the right eye. The aqueous humor collected from the right eye was positive for herpes simplex virus (HSV) DNA by PCR. The diagnosis of herpetic uveitis in the right eye was made due to clinical presentations and aqueous humor examination. CONCLUSION: Herpetic virus reactivation might occasionally occur after intraocular surgery in patients without prior ocular viral diseases, inducing atypical postoperative intraocular inflammation.

Long-term outcome in corneal endotheliitis with molecular detection of herpes simplex virus 1 and human herpes virus 6: a case report.

BACKGROUND: Human herpesvirus 6B (HHV-6B) is known to cause exanthema subitem and has been detected in various ocular diseases, including keratitis, uveitis, optic neuritis, and endophthalmitis; however, the long-term outcome after the reactivation of HHV-6B has not been well-addressed. Sugita et al. previously reported the concomitant presence of HHV-6B with herpes simplex virus-1 (HSV-1) in the aqueous fluid at the onset of corneal endotheliitis. We focused on the same patient with corneal endotheliitis, in whom both HSV-1 and HHV-6B sequences were observed, and reported the clinical course and long-term outcomes. CASE PRESENTATION: A 64-year-old woman was referred to our center for visual disturbances in the left eye. Her best-corrected visual acuity in the left eye was 0.5 and the left intraocular pressure was elevated to 33 mmHg. Mid-sized keratic precipitates and 2+ cells were observed in the anterior chamber with corneal endothelial edema and reduction of the corneal endothelial cell density to 1828 cells/mm2. The patient was diagnosed with corneal endotheliitis with increased intraocular pressure. Polymerase chain reaction analysis revealed the concomitant presence of both HSV-1 and HHV-6B sequences in the left aqueous fluid. After treatment with oral valacyclovir and topical betamethasone, her intraocular inflammation gradually improved and has not recurred at 12 years after corneal endotheliitis onset although corneal opacity remained. CONCLUSIONS: Reactivation of HHV-6B infection might be associated with HSV-1 corneal endotheliitis; however, no serious late sequelae occurred after appropriate treatment for HSV-1 infection in this immunocompetent host.

Multisystem inflammatory syndrome in children during severe acute respiratory syndrome coronavirus-2 pandemic in Turkey: A single-centre experience.

AIM: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection may result in a life-threatening hyperinflammatory condition named multisystem inflammatory syndrome in children (MIS-C). We aimed to assess demographics, clinical presentations, laboratory characteristics and treatment outcomes of patients with MIS-C. METHODS: We performed a retrospective study of patients with MIS-C managed between August 2020 and March 2021 at Dr. Sami Ulus Maternity Child Health and Diseases Training and Research Hospital in Turkey. RESULTS: A total of 45 patients (23 male, 51%) with a median age of 8.7 years (interquartile range: 5.6-11.7 years) were enrolled to study. The SARS-CoV-2 serology was positive in 43 (95%) patients. Organ-system involvement included the dermatologic in 41 (91%), cardiovascular in 39 (87%), hematologic in 36 (80%) and gastrointestinal in 36 (80%) patients. Acute anterior uveitis was diagnosed in nine (20%) patients. Two patients presented with clinical findings of deep neck infection such as fever, neck pain, trismus, swelling and induration on the cervical lymph node. One patient presented with Henoch-Schonlein purpura-like eruption. Coronary artery dilatation was detected in five (11%) patients. For treatment of MIS-C, intravenous immunoglobulin was used in 44 (98%) patients, methylprednisolone in 27 (60%) and anakinra in 9 (20%) patients. The median duration of hospitalisation was nine days. All patients recovered. CONCLUSIONS: Children with MIS-C might have variable clinical presentations. Acute anterior uveitis might be a prominent presentation of MIS-C and require ophthalmological examination. It is essential to make patient-based decisions and apply a stepwise approach for the treatment of this life-threatening disease.

Comparison of metabolic profiles in aqueous humour of Fuchs' syndrome and presumed viral-induced anterior uveitis patients.

BACKGROUND: To investigate and compare the metabolic profiles in the aqueous humour of Han Chinese patients with Fuchs' syndrome and presumed viral-induced anterior uveitis (PVIAU). METHODS: The metabolites in the aqueous humour of 20 Fuchs' syndrome patients, 20 PVIAU patients and 20 senile cataract control patients were detected by liquid chromatography with mass spectrometry. Differential metabolites were analysed by Student's t test, multivariate analysis, cluster analysis and correlation analysis. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was applied to explore the potential disrupted metabolic pathways in Fuchs' syndrome and PVIAU. RESULTS: Comparisons of metabolic profiles identified 29 differential metabolites between Fuchs' syndrome patients and controls, 36 differential metabolites between PVIAU patients and controls, and 30 differential metabolites between Fuchs' syndrome patients and PVIAU patients. DL-serine was markedly elevated in Fuchs' syndrome, and 1-palmitoyl-sn-glycero-3-phosphocholine in PVIAU. KEGG pathway analysis suggested that the differential metabolites in Fuchs' syndrome compared with control were mostly enriched in central carbon metabolism in cancer, adenosine triphosphate-binding cassette (ABC) transporters and mineral absorption, while those in PVIAU compared with control were mostly enriched in protein digestion and absorption, biosynthesis of unsaturated fatty acids, and ABC transporters. The metabolic pathways differentially affected in Fuchs' syndrome compared to PVIAU included central carbon metabolism in cancer, protein digestion and absorption and ascorbate and aldarate metabolism. CONCLUSIONS: In Fuchs' syndrome and PVIAU patients, the aqueous humour exhibited specific metabolic profiles and enriched metabolic pathways, which provides a better understanding of the pathogenesis of Fuchs' syndrome and PVIAU in Han Chinese patients.

An unusual case of eosinophilic uveitis in a cat.

An 8-year-old female spayed domestic short-haired cat was examined for recurrent unilateral anterior uveitis of 5 month's duration. No underlying cause was found on infectious disease screening. The cat also had a 4-year history of allergic or immune-mediated skin disease that was controlled with corticosteroid injections followed by long-term oral cyclosporine therapy. Medical management with frequent topical anti-inflammatory drugs (prednisolone acetate 1% suspension, diclofenac 0.1% solution) controlled the intraocular inflammation; however, the uveitis would relapse when therapy was discontinued. Eventually, secondary glaucoma developed OD and the eye was enucleated. At the time of surgery, a complete blood count showed a mild eosinophilia. Histopathology revealed a marked panuveitis characterized by an abundant accumulation of mixed inflammatory cells, with a predominantly eosinophilic infiltrate in the anterior chamber, iris, ciliary body, and choroid. No etiologic agents were found on serial sections, and there were no cellular criteria for malignancy noted. Nine months after enucleation, the chronic dermatitis appeared to be in remission despite no further medical management. This is the first known report of a primarily eosinophilic uveitis in a cat with chronic allergic skin disease and may be considered an ocular variant of feline eosinophilic granuloma complex.

The feasibility of clinical evaluation for anterior uveitis through spectral-domain optical coherence tomography in dogs.

OBJECTIVE: To evaluate the clinical application of spectral-domain optical coherence tomography (SD-OCT) for anterior uveitis in dogs. Animals and procedures Client-owned dogs presenting with anterior uveitis and clinically healthy dogs were enrolled in this study. Included eyes were divided into 5 groups by flare grade and 3 groups by cell grade through slit-lamp biomicroscopy. Each eye was examined using SD-OCT following slit-lamp biomicroscopy. The ratio of aqueous signal intensity to air signal intensity, which is called the aqueous-to-air relative intensity (ARI) index, was used to evaluate the flare grade. Cell number, central corneal thickness (CCT), and the presence of keratic precipitates (KPs) were analyzed on SD-OCT. The OCT parameters, including ARI index, cell number, and CCT, were compared to the slit-lamp clinical flare and cell grade. RESULTS: Thirty-six eyes with anterior uveitis and 27 healthy eyes were enrolled. The ARI index showed a significant correlation with clinical flare grade (rs  = 0.811, p < .001). In multiple regression analysis, the ARI index and CCT showed a significant negative correlation (r = -0.258, p = .044). The number of cells on SD-OCT significantly increased with cell grade on slit-lamp biomicroscopy (rs  = 0.653, p < .001). The clinical flare grade and CCT were significantly correlated in the partial correlation analysis after controlling for age (partial correlation coefficient = 0.471, p = .002). KPs were observed in 61% of the eyes with flare using SD-OCT (22/36 eyes). CONCLUSIONS: Spectral-domain optical coherence tomography could provide quantitative information, including the ARI index, cell counts, and CCT in dogs. SD-OCT is an auxiliary modality for slit-lamp biomicroscopy when evaluating anterior uveitis in dogs.

Covid-19 association with anterior uveitis (post-covid acute anterior uveitis).

The Covid-19 outbreak in Wuhan on 31st December 2019 soon became a pandemic. Ocular manifestations in post covid patients have been widely reported. Anterior uveitis is a common form of intraocular inflammation observed on a daily basis by Ophthalmologists. Diagnosis of AAU is relatively simple but identification of its etiology is difficult, specifically with Covid-19. Post Covid-19 AAU is not reported in Pakistan yet. The patient in the given case is investigated thoroughly, no possible cause of AAU is identified. The patient was managed for uveitis.

Aqueous Humor Analysis in Overlapping Clinical Diagnosis of Cytomegalovirus and Rubella Virus Anterior Uveitis.

Background and Objectives: A cross-sectional single-center study was conducted to investigate the etiology in hypertensive anterior uveitis whose clinical features are not fully distinctive from cytomegalovirus or from rubella virus and to demonstrate the possible coexistence of both these viruses in causing anterior uveitis. Materials and Methods: The clinical charts of a cohort of patients with hypertensive viral anterior uveitis of uncertain origin consecutively seen in a single center from 2019 to 2022 were retrospectively reviewed; data on the clinical features, aqueous polymerase chain reaction, and antibody response to cytomegalovirus and rubella virus were collected. Results: Forty-three eyes of as many subjects with viral anterior uveitis of uncertain origin were included. Thirty-two patients had an aqueous polymerase chain reaction or antibody index positive to cytomegalovirus only, while 11 cases had an aqueous antibody response to both cytomegalovirus and rubella virus. This latter overlapping group had a statistically significant higher rate of hypochromia and anterior vitritis (p-value: 0.02 and < 0.001, respectively). Conclusions: The simultaneous presence of intraocular antibodies against cytomegalovirus and rubella virus could redefine the differential diagnosis of hypertensive viral anterior uveitis, demonstrating a possible "converged" immune pathway consisting in a variety of stimuli.