Congenital amegakaryocytic thrombocytopenia (CAMT, MIM# 604498) is a rare congenital bone marrow failure syndrome which presents early in life with abnormal bleeding because of thrombocytopenia. Classically, megakaryocytes are decreased to absent in the bone marrow. The development of aplastic anemia early in childhood has led to the recommendation for early stem cell transplantation. Quantitative or loss-of-function mutations in the myeloproliferative leukemia gene (c-mpl), whose gene product functions as the thrombopoietin receptor, have been identified as causative for CAMT. Approximately 100 cases of CAMT are published in the medical literature. We describe 2 cases of CAMT who demonstrate disparate clinical courses, thereby highlighting phenotypic differences and increasing awareness of this clinical entity.
Departments of *Pediatrics
†Pathology, Stanford University School of Medicine, Stanford, CA
C.L.: abstracted the patient data and drafted the initial manuscript. E.A.: obtained data on case 1. R.O.: provided the images and title for Figure 1. M.J.: obtained data on case 2. All authors reviewed and revised the manuscript and approved the final manuscript as submitted and agree to be accountable for all aspects of the work.
The authors declare no conflict of interest.
Reprints: Clara Lo, MD, 1000 Welch Road, Suite 300, Palo Alto, CA 94304-1812 (e-mail: email@example.com).
Received December 15, 2016
Accepted July 12, 2017