Hemophilia A and B are defined as rare disorders in the United States, affecting fewer than 200,000 Americans. Bleeding and clotting disorders less common that hemophilia A and B exist worldwide, and knowledge about these conditions and their management lags far behind. It is these very rare and heterogeneous disorders that are addressed in a new online resource— the Rare Coagulation Disorders Resource Room.

The Resource Room, a dynamic, open-access website, was developed as a collaboration of the international RBDD Registry, the Indiana Hemophilia & Thrombosis Center, and the Rare Coagulation Disorders Subcommittee of the Medical and Scientific Advisory Council of the National Bleeding Disorders Foundation.

The educational content in the  Resource Room was written by experts in coagulation disorders and represents revised and rewritten information previously available in articles published in the 2008 supplement of Haemophilia (see link at the top of this page). The content has been formatted to provide current and searchable information on topics such as the basic science, clinical management, available laboratory and genetic testing, clinical trials, and global research initiatives for these very rare and heterogeneous coagulation disorders.

The Resource Room aims to serve as a first-line educational source for both healthcare providers and individuals with these coagulation disorders. Healthcare professionals often have little direct experience with these disorders, with limited resources for their diagnosis and treatment. Moreover, as rare coagulation disorders represent a small potential commercial market, few, if any, specific therapies exist for these conditions. As a result, affected individuals often face delayed diagnosis, insufficient laboratory evaluation, and limited treatment options.

Recent pharmaceutical efforts have focused on the development of safe and accessible products for a few of these rare disorders. In addition, global registries and networks have been developed to provide coordinated and consistent data collection to increase knowledge of these conditions and their management.

Global programs continue to promote international data harmonization. In the United States, the American Thrombosis and Hemostasis Network has expanded its data collection system to include individuals affected with very rare coagulation disorders followed through the U.S. federal network of hemophilia treatment centers. In Europe, Dr. Flora Peyvandi, under the auspices of the International Society on Thrombosis and Haemostasis, has spearheaded the development of an international network of care providers and a registry to better identify the number of affected individuals worldwide and define the clinical manifestations and sequelae of these disorders.

The Rare Coagulation Disorders Resource Room  represents an important step in a global initiative to further enhance these efforts, with the goal of improving the health and quality of life of individuals with rare coagulation disorders. We encourage the international rare coagulation disorders community to contribute to, and benefit from, this free global endeavor.


Explore the Rare Coagulation Disorders Resource Room.


Flora Peyvandi, MD, PhD
Associate Professor of Internal Medicine
Angelo Bianchi Bonomi Hemophilia and Thrombosis Center
University of Milan, Milan, Italy

Amy D. Shapiro, MD
Medical Director
Indiana Hemophilia and Thrombosis Center
Indianapolis, IN, United States


Rare Coagulation Disorders Subcommittee of the National Bleeding Disorders Foundation


Suchitra S. Acharya, MD
Pediatric Hematologist
Hematology/Oncology/Stem Cell Transplantation
Cohen Children’s Medical Center of New York
New Hyde Park, NY, United States

Craig M. Kessler, MD
Unit Director
Comprehensive Hemophilia and Thrombophilia Treatment Center
Georgetown University Lombardi Cancer Center
Washington, DC, United States

Marion A. Koerper, MD
Emerita Professor of Pediatric Hematology
UCSF Children’s Hospital
San Francisco, CA, United States

Marilyn Manco-Johnson, MD
Hemophilia and Thrombosis Center
University of Colorado
Aurora, CO, United States

Diane J. Nugent, MD
Medical Director
CHOC Children’s Hospital/UC Irvine Medical Center, and Center for Comprehensive Care and Diagnosis of Inherited Blood Disorders
Orange, CA, United States

Amy D. Shapiro, MD
Medical Director
Indiana Hemophilia and Thrombosis Center
Indianapolis, IN, United States