Síndrome de Blau: infiltrados subepiteliais como manifestações oftalmológicas incomuns / Blau Syndrome: subepithelial infiltrates as uncommon ophthalmologic manifestation

Resumo A Síndrome de Blau é uma doença de caráter hereditário autossômico dominante a qual também pode ocorrer de forma esporádica via mutação "de novo". Em geral, tem aparecimento precoce ainda na primeira infância e sua tríade clássica inclui artrite, dermatite e uveíte. Este trabalho visa relatar as manifestações clínicas e principalmente oftalmológicas de uma paciente diagnosticada com Síndrome de Blau com ênfase ao achado incomum de infiltrados corneanos subepiteliais, raramente descrito na literatura.

Abstract The Blau syndrome is an autosomal dominant hereditary disease which can also occur sporadically via "de novo" mutation. Overall it has early onset and its classic triad includes arthritis, dermatitis and uveitis. This paper describes clinical and mainly especially ophthalmologic manifestations of a patient diagnosed with Blau syndrome with emphasis on an uncommon finding of corneal subepithelial infiltrates, rarely described in the literature.

Two Likely Pathogenic Variants of COL2A1 in Unrelated Korean Patients With Ocular-Only Variants of Stickler Syndrome: The First Molecular Diagnosis in Korea

Stickler syndrome is a genetically heterogeneous disorder that affects the ocular, auditory, and musculoskeletal systems. Ocular-only variant of Stickler syndrome type 1 (OSTL1) is characterized by high risk of retinal detachment without systemic involvement and is caused by alternatively spliced exon 2 mutation of COL2A1. We report the cases of two Korean families with OSTL1 carrying likely pathogenic variants of COL2A1. All patients presented with membranous vitreous anomaly, peripheral retinal degeneration, and/or rhegmatogenous retinal detachment, but no systemic manifestations. By genetic analysis, two likely pathogenic non-exon 2 variants, c.2678dupC (p.Ala895Serfs*49) and c.3327+ 1G>C, were identified in COL2A1. Our results demonstrate that COL2A1 defects in OSTL1 are not confined to mutations in exon 2. Together with molecular data, ophthalmologists should consider genetic diagnosis of Stickler syndrome in patients with vitreous anomaly to prevent blindness from retinal detachment. To our knowledge, this is the first report of genetically confirmed OSTL1 in Korea.

Crosstalk between FLS and chondrocytes is regulated by HIF-2alpha-mediated cytokines in arthritis

Rheumatoid arthritis (RA) and osteoarthritis (OA), two common types of arthritis, affect the joints mainly by targeting the synovium and cartilage. Increasing evidence indicates that a significant network connects synovitis and cartilage destruction during the progression of arthritis. We recently demonstrated that hypoxia-inducible factor (HIF)-2alpha causes RA and OA by regulating the expression of catabolic factors in fibroblast-like synoviocytes (FLS) or chondrocytes. To address the reciprocal influences of HIF-2alpha on FLS and chondrocytes, we applied an in vitro co-culture system using a transwell apparatus. When co-cultured with HIF-2alpha-overexpressing chondrocytes, FLS exhibited increased expression of matrix metalloproteinases and inflammatory mediators, similar to the effects induced by tumor-necrosis factor (TNF)-alpha treatment of FLS. Moreover, chondrocytes co-cultured with HIF-2alpha-overexpressing FLS exhibited upregulation of Mmp3 and Mmp13, which is similar to the effects induced by interleukin (IL)-6 treatment of chondrocytes. We confirmed these differential HIF-2alpha-induced effects via distinct secretory mediators using Il6-knockout cells and a TNF-alpha-blocking antibody. The FLS-co-culture-induced gene expression changes in chondrocytes were significantly abrogated by IL-6 deficiency, whereas TNF-alpha neutralization blocked the alterations in gene expression associated with co-culture of FLS with chondrocytes. Our results further suggested that the observed changes might reflect the HIF-2alpha-induced upregulation of specific receptors for TNF-alpha (in FLS) and IL-6 (in chondrocytes). This study broadens our understanding of the possible regulatory mechanisms underlying the crosstalk between the synovium and cartilage in the presence of HIF-2alpha, and may suggest potential new anti-arthritis therapies.

Evidence to show MHC-linked factors other than HLA-B27 governing susceptibility to spondylo-arthropathies in Asian Indians.

The HLA antigen profile of 129 North Indian patients with ankylosing spondylitis, 66 patients with Reiter's syndrome and 57 patients with 'unclassifiable' arthritis was compared with 380 normal, healthy controls. Besides B27 which appeared with a significantly increased frequency in the three patient groups, other HLA antigens, viz. A2 and B35, showed deviated frequencies. The HLA supratype A2, B27 was found to be at an elevated frequency in patients with ankylosing spondylitis and unclassifiable arthritis whereas the B35, B27 combination showed a decreased frequency in our Reiter's syndrome sample. These data suggest that besides B27, other HLA-linked factors influence susceptibility to spondylitic disorders and might act as 'modifier' genes for the type and severity of spondylo-arthropathy in a B27-positive individual.