Prevalence and levels of serum antibodies to gram negative microorganisms in Turkish patients with HLA-B27 positive acute anterior uveitis and controls

Spondyloarthritis, Acute Anterior Uveitis, and Fungi: Updating the Catterall-King Hypothesis

Spondyloarthritis is a common type of arthritis which affects mostly adults. It consists of idiopathic chronic inflammation of the spine, joints, eyes, skin, gut, and prostate. Inflammation is often asymptomatic, especially in the gut and prostate. The HLA-B*27 allele group, which presents intracellular peptides to CD8+ T cells, is by far the strongest risk factor for spondyloarthritis. The precise mechanisms and antigens remain unknown. In 1959, Catterall and King advanced a novel hypothesis explaining the etiology of spondyloarthritis: an as-yet-unrecognized sexually acquired microbe would be causing all spondyloarthritis types, including acute anterior uveitis. Recent studies suggest an unrecognized sexually acquired fungal infection may be involved in prostate cancer and perhaps multiple sclerosis. This warrants reanalyzing the Catterall-King hypothesis based on the current literature. In the last decade, many links between spondyloarthritis and fungal infections have been found. Antibodies against the fungal cell wall component mannan are elevated in spondyloarthritis. Functional polymorphisms in genes regulating the innate immune response against fungi have been associated with spondyloarthritis (CARD9 and IL23R). Psoriasis and inflammatory bowel disease, two common comorbidities of spondyloarthritis, are both strongly associated with fungi. Evidence reviewed here lends credence to the Catterall-King hypothesis and implicates a common fungal etiology in prostate cancer, benign prostatic hyperplasia, multiple sclerosis, psoriasis, inflammatory bowel disease, and spondyloarthritis. However, the evidence available at this time is insufficient to definitely confirm this hypothesis. Future studies investigating the microbiome in relation to these conditions should screen specimens for fungi in addition to bacteria. Future clinical studies of spondyloarthritis should consider antifungals which are effective in psoriasis and multiple sclerosis, such as dimethyl fumarate and nystatin.

The Rate of Helicobacter pylori Seropositivity in a Group of Korean Patients with HLA-B27-Associated Acute Anterior Uveitis

Purpose

To investigate an association between Helicobacter pylori seropositivity and HLA-B27-positive acute anterior uveitis (AAU) in Korean patients.

Methods

Retrospective analysis was performed with data from 106 patients previously diagnosed with AAU without clinical evidence of spondyloarthropathy. Serum immunoglobulin G antibodies to H. pylori were measured by enzyme-linked immunosorbent assay, and HLA typing was performed using polymerase chain reaction of DNA amplification. We included 72 non-uveitis patients and 35 age- and sex-matched healthy controls in the study.

Results

Of the 106 patients with AAU, 41 (38.7%) were HLA-B27-positive, and 45 (42.5%) were seropositive for H. pylori. Patients with HLA-B27-positive AAU had a significantly lower prevalence of H. pylori seropositivity compared to those with HLA-B27-negative AAU and healthy controls (24.4% vs. 53.8%, p = 0.003; 24.4% vs. 57.1%, p = 0.004, respectively). In the non-uveitis group, however, HLA-B27-positive patients exhibited similar H. pylori seropositivity prevalence to HLA-B27-negative patients and healthy controls (45.5% vs. 55.7%, p = 0.529; 45.5% vs. 57.1%, p = 0.497, respectively). In multivariate analysis, a low prevalence of H. pylori seropositivity was significantly associated with HLA-B27-positive AAU (odds ratio = 0.340, 95% confidence interval 0.135–0.855, p = 0.022).

Conclusions

Our results suggest an inverse association between H. pylori seropositivity and HLA-B27-positive AAU. Further investigation of this association is needed, given the low prevalence of H. pylori seropositivity observed in patients with HLA-B27-positive AAU.

Plasma metabonomics study of the patients with acute anterior uveitis based on ultra-performance liquid chromatography-mass spectrometry

BACKGROUND

The identification of the biomarkers of patients with acute anterior uveitis (AAU) may allow for a less invasive and more accurate diagnosis, as well as serving as a predictor in AAU progression and treatment response. The aim of this study was to identify the potential biomarkers and the metabolic pathways from plasma in patients with AAU.

METHODS

Both plasma metabolic biomarkers and metabolic pathways in the AAU patients versus healthy volunteers were investigated using ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and a metabonomics approach. The principal component analysis (PCA) was used to separate AAU patients from healthy volunteers as well as to identify the different biomarkers between the two groups. Metabolic compounds were matched to the KEGG, METLIN, and HMDB databases, and metabolic pathways associated with AAU were identified.

RESULTS

The PCA for UPLC-MS data shows that the metabolites in AAU patients were significantly different from those of healthy volunteers. Of the 4,396 total features detected by UPLC-MS, 102 features were significantly different between AAU patients and healthy volunteers according to the variable importance plot (VIP) values (greater than two) of partial least squares discriminate analysis (PLS-DA). Thirty-three metabolic compounds were identified and were considered as potential biomarkers. Meanwhile, ten metabolic pathways were found that were related to the AAU according to the identified biomarkers.

CONCLUSIONS

These data suggest that metabolomics study can identify potential metabolites that differ between AAU patients and healthy volunteers. Based on the PCA, PLS-DA, several potential metabolic biomarkers and pathways in AAU patients were found and identified. In addition, the UPLC-MS technique combined with metabonomics could be a suitable systematic biology tool in research in clinical problems in ophthalmology, and can provide further insight into the pathophysiology of AAU.