NORD gratefully acknowledges Barry S. Coller, MD, David Rockefeller Professor of Medicine; Head, Allen and Frances Adler Laboratory of Blood and Vascular Diseases, The Rockefeller University, for assistance in the preparation of this report.
The symptoms of Glanzmann thrombasthenia usually begin at birth or shortly thereafter and include the tendency to bruise and bleed easily and sometimes profusely, especially after surgical procedures. Other symptoms may include susceptibility to easy bruising, nosebleeds (epistaxis), bleeding from the gums (gingival), intermittent gastrointestinal bleeding, and/or variably large red or purple colored spots on the skin that are caused by bleeding in the skin (purpura). Women with GT often also have unusually heavy menstrual bleeding, irregular uterine bleeding, and excess bleeding in childbirth. Rarely, internal bleeding and blood in the urine (hematuria) can occur. The severity of the symptoms varies greatly. Some affected individuals have mild bruising and others have severe hemorrhages that can be life threatening.
Glanzmann thrombasthenia is inherited in an autosomal recessive pattern. An abnormality in either the gene for IIb (glycoprotein IIb; GPIIb) or the gene for β3 (glycoprotein IIIa; GPIIIa) results in an abnormal platelet IIbβ3 (GPIIb/IIIa) integrin family receptor and prevents platelets from forming a plug when bleeding occurs. Many different abnormalities in these genes have been identified. Recent evidence suggests that approximately 0.5% of healthy individuals in the general population are probably carrying one gene with an abnormal variant of aIIb or β3.
Genetic diseases are determined by the combination of genes for a particular trait that are on the chromosomes received from the father and the mother. Recessive genetic disorders occur when an individual inherits an abnormal variant of a gene from each parent. If an individual receives one normal gene and one abnormal variant gene for the disease, the person will be a carrier for the disease, but usually will not show symptoms. This is true for carriers of Glanzmann thrombasthenia. The risk for two carrier parents to both pass the defective gene and, therefore, have an affected child is 25% with each pregnancy. The risk to have a child who is a carrier, like the parents, is 50% with each pregnancy. The chance for a child to receive the normal genes from both parents and therefore be genetically normal for that particular trait is 25%. The risk is the same for males and females.
Glanzmann thrombasthenia is a rare disorder that affects males and females in equal numbers. The symptoms of this disease are usually apparent at birth (neonates) or during infancy. Approximately 500 cases have been reported, but many cases have probably not been reported. This condition occurs with greater frequency in populations in which intermarriage within a group (consanguinity) is more prevalent such as in some regions of the Middle East, India, and France.
Most individuals affected with Glanzmann thrombasthenia have a normal number of platelets but have a prolonged bleeding time, which means it takes longer than usual for a standardized cut to stop bleeding. Platelet aggregation studies are abnormal and show that platelets are not able to clump together when stimulated as they should to form platelet aggregates. Glanzmann thrombasthenia is definitively diagnosed by tests that determine if there is a deficiency of the aIIbβ3 (GPIIb/GPIIIa) receptor. These tests usually involve monoclonal antibodies and flow cytometry. Genetic tests can identify the DNA mutations responsible for the disorder.
Carrier and prenatal testing by DNA analysis is possible if the specific gene abnormality has been identified in an affected family member. Otherwise prenatal testing can be performed based on analyzing the fetus’s platelet aIIbβ3.
Some individuals with GT may require blood platelet transfusions. Since transfusions may continue to be necessary throughout life, affected individuals may benefit from transfusions from HLA matched donors. Some patients develop antibodies to transfused platelets and these antibodies may diminish the benefit from subsequent platelet transfusions.
In 2014, NovoSeven RT, a recombinant factor VIIa product, was approved to treat Glanzmann thrombasthenia. This medication is indicated to treat bleeding episodes and perioperative management when platelet transfusions are not effective. NovoSeven RT is manufactured by Novo Nordisk.
Treatment is usually given prior to most surgical procedures or should be available if needed. Platelet transfusions are usually necessary prior to delivery.
Nosebleeds can usually be treated with nasal packing or application of foam soaked in thrombin. Regular dental care is important to prevent bleeding from the gums.
Hormonal therapy can be used to suppress menstrual periods.
Other treatment of GT is symptomatic and supportive, including use of antifibrinolytic agents.
Genetic counseling is recommended for people with GT and their families.
Bone marrow transplantation has successfully cured a number of patients with severe disease.
Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. government funding, and some supported by private industry, are posted on this government web site.
For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:
Tollfree: (800) 411-1222
TTY: (866) 411-1010
Some current clinical trials also are posted on the following page on the NORD website:
For information about clinical trials sponsored by private sources, contact:
For information about clinical trials conducted in Europe, contact:
Rao, A.K., Coller, B.S. Hereditary qualitative platelet disorders. In Williams Hematology, 9th Edition, Kaushansky, K., Lichtman, M.A., Prchal, J.T., Levi, M.M., Press, O.W., Burns, L.J., Caligiuri, M.A., eds. McGraw-Hill, Inc., New York, 2015, pps 2039-2071.
Mitchell WB and French DL. Glanzmann Thrombasthenia. In: The NORD Guide to Rare Disorders, Philadelphia: Lippincott, Williams and Wilkins; 2003:383-384.
Nurden AT, Pillois X. ITGA2B and ITGB3 gene mutations associated with Glanzmann thrombasthenia. Platelets. 2018;29:98-101.
Buitrago, L., Rendon, A., Liang, Y., Turro, E., Simeoni, I., Negri, A., ThromboGenomics Consortium, Filizola, M., Ouwehand, W.H., Coller. B.S. αIIbβ3 variants defined by next generation sequencing: predicting variants likely to cause Glanzmann thrombasthenia. PNAS. 2015;112:E1898-19907.
Nurden AT, Fiore M, Nurden P, et al. Glanzmann thrombasthenia: a review of ITGA2B and ITGB3 defects with emphasis on variants, phenotypic variability, and mouse models. Blood 2011;118:5996-6005.
Wiegering V, Winkler B, Langhammer F, et al. Allogeneic hematopoietic stem cell transplantation in Glanzmann thrombasthenia complicated by platelet alloimmunization. Klin Padiatr. 2011;223:173-175.
Kitko CL, Levine JE, Matthews DC, et al. Successful unrelated donor cord blood transplantation for Glanzmann’s thrombasthenia. 2011;15:e42-46.
Miller W, Dunn A, Chiang KY. Sustained engraftment and resolution of bleeding phenotype after unrelated cord blood hematopoietic stem cell transplantation for severe glanzmann thrombasthenia. J Pediatr Hematol Oncol. 2009;31:437-439.
Ishaqi MK, El-Hayek M, Gassas A, et al. Allogeneic stem cell transplantation for Glanzmann thrombasthenia. Pediatr Blood Cancer. 2009;52:682-683.
Di Minno G, Coppola A, Di Minno MN, et al. Glanzmann’s thrombasthenia (defective platelet integrin alphaIIb-beta3): proposals for management between evidence and open issues. Thromb Haemostas. 2009;102:1157-1164.
Connor P, Khair K, Liesner R, et al. Stem cell transplantation for children with Glanzmann thrombasthenia. Br J Hematol 2008;140:568-571.
Bellucci s, Damaj G, Boval B, et al. Bone marrow transplantation in severe Glanzmann’s thrombasthenia with antiplatelet alloimmunization. Bone Marrow Transplant 2000;25:327-330.
French DL, Coller BS. Hematologically important mutations: Glanzmann thrombasthenia. Blood Cells Mol Dis. 1997;23:39-51.
George JN, Caen JP, Nurden AT. Glanzmann thrombasthenis:the spectrum of clinical disease. Blood 1990;75:1383-1395.
Ali ZA. Glanzmann Thrombasthenia.Medscape. http://emedicine.medscape.com/article/200311-overview Updated: Dec 29, 2017. Accessed March 8, 2018.
Online Mendelian Inheritance in Man (OMIM). The Johns Hopkins University. Glanzmann Thrombasthenia; GT. Entry No: 273800. Last Edited 09/23/2011. Available at: http://omim.org/entry/273800 Accessed March 8, 2018.
The information in NORD’s Rare Disease Database is for educational purposes only and is not intended to replace the advice of a physician or other qualified medical professional.
The content of the website and databases of the National Organization for Rare Disorders (NORD) is copyrighted and may not be reproduced, copied, downloaded or disseminated, in any way, for any commercial or public purpose, without prior written authorization and approval from NORD. Individuals may print one hard copy of an individual disease for personal use, provided that content is unmodified and includes NORD’s copyright.
National Organization for Rare Disorders (NORD)
55 Kenosia Ave., Danbury CT 06810 • (203)744-0100