Gabriel J. Tobón, Colombia

Fundación Valle del Lili, Universidad Icesi GIRAT

Presenter of 2 Presentations

RNASEQ ANALYSIS OF THE IMMUNOLOGICAL DISTURBANCES IN PYODERMA GANGRENOSUM

Session Type
PARALLEL SESSIONS
Date
29.05.2021, Saturday
Session Time
13:30 - 15:30
Room
HALL E
Lecture Time
14:50 - 15:00
Session Icon
Pre Recorded

Abstract

Background and Aims

Pyoderma gangrenosum (PG) is an inflammatory disease, which is histologically characterized by an inflammatory infiltrate mediated mainly by granulocytes without evidence of infection. The pathophysiology of this disease is not clear, primarily the uncontrolled production of pro-inflammatory cytokines, which activate neutrophils are the reason why PG is classified as auto-inflammatory. To evaluate the immune profile of the disease, we conducted an RNAseq analysis in skin biopsies of four patients with PG and four healthy controls.

Methods

After total RNA extraction, mRNA was obtained by an Oligo-dT sequence. Afterwards sequenced in an Illumina platform, the readings were mapped against the GRCh38 genome.

Results

We obtained information of 19799 genes, 2798 genes were up-regulated and 2842 down-regulated comparing PG vs. healthy skin. The primary 100 genes were selected in each group. After a functional enrichment analysis, the central up-regulated genes were lytic tissue-destroying genes such as MMPs but also wound healing and angiogenesis genes. Also, pro-inflammatory proteins and neutrophil chemokines, reported in the literature associated with PG, were identified. Besides, an exciting group of genes, S100A genes, were remarkably up-regulated, whose functions of regulating the immune response could trigger the excessive degranulation of neutrophils that damages tissue. Finally, we observed the down-regulation of skin structural support and permeability genes as KRT2 and CLDN10 and the low expression of epidermal growth factors such as ERBB4.

Conclusions

The homeostasis impairment of these molecules in the skin can trigger a PG-type lesion; these findings will be functionally validated in vitro and animal models.

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VARIABILITY OF CLINICAL CHARACTERISTICS AND OUTCOMES OF PATIENTS WITH ANCA-ASSOCIATED VASCULITIDES IN A LATIN-AMERICAN HOSPITAL

Session Type
PARALLEL SESSIONS
Date
31.05.2021, Monday
Session Time
10:00 - 12:00
Room
HALL A
Lecture Time
11:10 - 11:20
Session Icon
Pre Recorded

Abstract

Background and Aims

ANCA-associated vasculitis (AAV) are necrotizing vasculitis, predominantly affecting small vessels, and associated with ANCA specific for myeloperoxidase (MPO-ANCA) or proteinase 3 (PR3-ANCA), with a very varied clinical spectrum. This study aimed to describe the clinical characteristics of patients with ANCA-associated vasculitis (AAV) in the first disease presentation and the ultimate clinical control. Besides to determine serological characteristics, treatment, and outcomes.

Methods

A total of 68 patients with AAV diagnosed between January 2011 and June 2019, in a high-complexity Hospital in Cali - Colombia was retrospectively analyzed. The activity was established using the Birmingham Vasculitis Activity Score (BVAS).

Results

Altogether, 60.2% had granulomatosis with polyangiitis (GPA), 19.1% microscopic polyangiitis (MPA), and 17,6% eosinophilic granulomatosis with polyangiitis (EGPA). The mean age at diagnosis was 50,3 ± 15,4 years in GPA, 50,2 ± 14,5 years in MPA, and 49,2 ± 14,7 years in EGPA. Arthralgia and ear-nose-throat (ENT) symptoms were the most common at disease onset (Figure 1). The initial BVAS was 12 (3-18) in GPA patients. Outcomes were variable, 11 patients with end-stage chronic renal failure, and five patients requiring renal transplantation.

Conclusions

The prevalence of AAV and the clinical characteristics in Latin-American patients are unknown; for that reason, these studies are necessaries.

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