Rochester, Minnesota


Koster.Matthew@mayo.edu Clinical Profile


The research interests of Matthew J. Koster, M.D., are focused on the pathogenesis, epidemiology and treatment of all forms of vasculitis with particular emphasis on giant cell arteritis and Takayasu's arteritis. In addition, Dr. Koster and his vasculitis colleagues perform research on associated inflammatory conditions that can affect the arteries, including immunoglobulin G4 (IgG4)-related disease; retroperitoneal fibrosis (RPF); and vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic (VEXAS) syndrome.

Focus areas

  • Clinical trials in vasculitis. Dr. Koster and his colleagues collaborate with the pharmaceutical industry and the Vasculitis Clinical Research Consortium (VCRC) in performing national and international, multicenter clinical trials and evaluating new treatments for vasculitis. In addition, Dr. Koster is involved in the designing and implementation of clinical trials at Mayo Clinic with a goal to identify novel therapeutics that can be used in larger clinical trials for the treatment of vasculitis and its associated conditions.
  • Epidemiology studies in vasculitis and its associated conditions. Dr. Koster is engaged in epidemiologic research on giant cell arteritis, Takayasu's arteritis, IgG4-related disease, retroperitoneal fibrosis and VEXAS syndrome. Through understanding the trends in incidence, changes in diagnostic modalities, risk factors associated with disease development, frequency of disease-associated complications, and short- and long-term treatment outcomes, Dr. Koster seeks to identify knowledge gaps among these conditions that can be targeted to improve patient care and management.
  • Translational studies in vasculitis and inflammatory conditions. Dr. Koster is studying the underlying cellular and biochemical mechanisms of giant cell arteritis and retroperitoneal fibrosis with periaortitis through a close collaboration with Cornelia M. Weyand, M.D., Ph.D., with an aim to understand the pathophysiology of these conditions and to inform development of novel therapeutics. Through a partnership with Joerg Goronzy, M.D., Dr. Koster is evaluating the genetics and pathophysiology of IgG4-related disease. Additionally, Dr. Koster's collaboration with Jaeyun Sung, Ph.D., involves multiomic studies, which focus on genetic and protein signatures in tissues affected by vasculitis with the intent to further understand the pathomechanisms of these diseases, with the goal of identifying novel biomarkers that can be utilized in disease diagnosis and monitoring of disease activity.

Significance to patient care

Vasculitis and arterial inflammatory syndromes are rare but life-threatening diseases. Dr. Koster and his colleagues aim to improve the health and long-term outcomes of patients with vasculitis and associated arterial inflammatory conditions by gaining a greater understanding of the underlying mechanisms of these diseases in order to assist in earlier diagnosis, accurate disease monitoring and effective targeted treatments.

Professional highlights

  • Teacher of the Year, Rheumatology, Mayo Fellows Association, 2018 and 2021
  • Department of Medicine Laureate Award — Rheumatology, 2021
  • Outstanding Alumnus Research Award, Trinity Christian College, 2017
  • American College of Rheumatology, Distinguished Fellow Award, 2016
  • Philip S. Hench Award, Mayo Clinic Rheumatology, 2016


Primary Appointment

  1. Consultant, Division of Rheumatology, Department of Internal Medicine

Academic Rank

  1. Assistant Professor of Medicine


  1. Clinical Fellowship - Rheumatology Rheumatology Fellowship Program, Mayo Graduate School of Medicine, Mayo Clinic College of Medicine
  2. Chief Medical Resident - Internal Medicine Department of Medicine, Loyola University & Stritch School of Medicine
  3. Residency - Internal Medicine Department of Medicine, Loyola University & Stritch School of Medicine
  4. MD Loyola University Stritch School of Medicine
  5. BA - Biology, Theology Trinity Christian College

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