Evaluating Gut Imaging and Stool Biomarkers in Patients With Scleroderma-associated Gastrointestinal Disease

Overview

Systemic sclerosis (SSc) is characterized by autoimmunity and vasculopathy resulting in fibrosis of the skin and internal organs including the Gastrointestinal (GI) tract. Key unmet clinical needs are the availability of non-invasive biomarkers for early diagnosis of SSc-GI, further characterization of different stages of SSc-GI and SSc-GI treatment response. The investigators propose combining MRI FDG-PET with MRI T1-MOLLI mapping, which has been applied to cardiac imaging to quantify histologically correlated cardiac fibrosis. T1-MOLLI enables detection and quantification of diffuse fibrosis without the need for contrast. Aim 1: FDG-PET-MRI imaging (primary biomarker) and stool markers (secondary biomarker) will be compared between patients with VEDOSS/early SSc and those with late SSc not on immunosuppressive treatment. Aim 2: Evaluation of change in biomarker levels from pre-treatment baseline to 6 months (primary end-point) and 12-months (secondary end-point) following MMF treatment, in early SSc patients Using precision medicine approach in diagnosis and treatment evaluation, the investigators anticipate that this study will contribute significantly to advance management strategies for, and improve outcomes of SSc-GI disease.

1. Aim 1 Determine if FDG-PET-MRI imaging biomarkers differentiate patients with VEDOSS/ early SSc (predominantly inflammatory) from those with late SSc (predominantly fibrosis). Stool markers will be used as secondary biomarkers supporting inflammation. Study design: cross-sectional; The investigators will compare biomarkers between patients with VEDOSS/early SSc and those with late SSc not on immunosuppressive treatment. 2. Aim 2 Evaluate FDG-PET-MRI imaging biomarker change over a 6- and 12-month treatment period with mycophenolate mofetil (MMF) in patients with early SSc. Stool markers will be used as secondary biomarkers supporting inflammation. Study design: longitudinal; In early SSc patients, the investigators will determine change in biomarker levels from pre-treatment baseline to 6 months (primary end-point) and 12-months (secondary end-point) following MMF treatment. 3. Exploratory Aim: In patients with VEDOSS/early SSc not on immunosuppressive treatment, the investigators will characterize imaging and stool biomarker changes over one year.