Congenital amegakaryocytic thrombocytopenia

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

Overview

Congenital amegakaryocytic thrombocytopenia (CAMT) is a rare inherited disorder.^[1]^[2]^[3]

Historical Perspective

Classification

Pathophysiology

Causes

The cause for this disorder appears to be a mutation in the gene for the TPO receptor, c-mpl, despite high levels of serum TPO.^[4]^[5] In addition, there may be abnormalities with the central nervous system including the cerebrum and cerebellum which could cause symptoms.^[4]

Differentiating Congenital amegakaryocytic thrombocytopenia from Other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications, and Prognosis

Natural History

The primary manifestations are thrombocytopenia and megakaryocytopenia, or low numbers of platelets and megakaryocytes. There is an absence of megakaryocytes in the bone marrow with no associated physical abnormalities.^[6]

Complications

Prognosis

Diagnosis

Diagnostic Criteria

History and Symptoms

Physical Examination

Laboratory Findings

Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

The primary treatment for CAMT is bone marrow transplantation.^[7]

Bone Marrow/Stem Cell Transplant is the only thing that ultimately cures this genetic disease. Frequent platelet transfusions are required to ensure that platelet levels do not fall to dangerous levels, although this is not always the case. It is known for patients to continue to create very small numbers of platelets over time.

Surgery

Prevention

References

↑ Ballmaier M, Germeshausen M, Schulze H, et al. (January 2001). “c-mpl mutations are the cause of congenital amegakaryocytic thrombocytopenia”. Blood. 97 (1): 139–46. doi:10.1182/blood.V97.1.139. PMID 11133753.
↑ Germeshausen M, Ballmaier M, Welte K (March 2006). “MPL mutations in 23 patients suffering from congenital amegakaryocytic thrombocytopenia: the type of mutation predicts the course of the disease”. Hum. Mutat. 27 (3): 296. doi:10.1002/humu.9415. PMID 16470591.
↑ Rose MJ, Nicol KK, Skeens MA, Gross TG, Kerlin BA (June 2008). “Congenital amegakaryocytic thrombocytopenia: the diagnostic importance of combining pathology with molecular genetics”. Pediatr Blood Cancer. 50 (6): 1263–5. doi:10.1002/pbc.21453. PMID 18240171.
↑ ^4.0 ^4.1 Ihara K, Ishii E, Eguchi M, Takada H, Suminoe A, Good RA, Hara T (1999). “Identification of mutations in the c-mpl gene in congenital amegakaryocytic thrombocytopenia”. Proc. Natl. Acad. Sci. 96 (6): 3133–6. doi:10.1073/pnas.96.6.3132. PMC 15907. PMID 10077649.
↑ Ballmaier M, Germeshausen M, Schulze H, Cherkaoui K, Lang S, Gaudig A, Krukemeier S, Eilers M, Strauss G, Welte K (2001). “C-mpl mutations are the cause of congenital amegakaryocytic thrombocytopenia”. Blood. 97 (1): 139–46. doi:10.1182/blood.V97.1.139. PMID 11133753.
↑ Freedman MH, Estrov Z (1990). “Congenital amegakaryocytic thrombocytopenia: an intrinsic hematopoietic stem cell defect”. Am. J. Pediatr. Hematol. Oncol. 12 (2): 225–230. doi:10.1097/00043426-199022000-00020. PMID 2378417.
↑ King S, Germeshausen M, Strauss G, Welte K, Ballmaier M (December 2005). “Congenital amegakaryocytic thrombocytopenia: a retrospective clinical analysis of 20 patients”. Br. J. Haematol. 131 (5): 636–44. doi:10.1111/j.1365-2141.2005.05819.x. PMID 16351641.

External links

Amegakaryocytic Thrombocytopenia research study of Inherited Bone Marrow Failure Syndromes (IBMFS)
CAMT Specific Infant Bone Marrow Transplant Journal – One of the few non Medical Research related sources on the web with some information on CAMT. There appears to be no generic resource for CAMT patients on the web, and this is potentially due to the rariety of the disease
https://www.facebook.com/topic.php?uid=38970584460&topic=6387#/group.php?gid=38970584460 This is the closest thing to a ‘support group’ for this condition.

[pmid11133753-1] Ballmaier M, Germeshausen M, Schulze H, et al. (January 2001). “c-mpl mutations are the cause of congenital amegakaryocytic thrombocytopenia”. Blood. 97 (1): 139–46. doi:10.1182/blood.V97.1.139. PMID 11133753.

[pmid16470591-2] Germeshausen M, Ballmaier M, Welte K (March 2006). “MPL mutations in 23 patients suffering from congenital amegakaryocytic thrombocytopenia: the type of mutation predicts the course of the disease”. Hum. Mutat. 27 (3): 296. doi:10.1002/humu.9415. PMID 16470591.

[pmid18240171-3] Rose MJ, Nicol KK, Skeens MA, Gross TG, Kerlin BA (June 2008). “Congenital amegakaryocytic thrombocytopenia: the diagnostic importance of combining pathology with molecular genetics”. Pediatr Blood Cancer. 50 (6): 1263–5. doi:10.1002/pbc.21453. PMID 18240171.

[Ihara-4] 4.0 ^4.1 Ihara K, Ishii E, Eguchi M, Takada H, Suminoe A, Good RA, Hara T (1999). “Identification of mutations in the c-mpl gene in congenital amegakaryocytic thrombocytopenia”. Proc. Natl. Acad. Sci. 96 (6): 3133–6. doi:10.1073/pnas.96.6.3132. PMC 15907. PMID 10077649.

[Ballmaier-5] Ballmaier M, Germeshausen M, Schulze H, Cherkaoui K, Lang S, Gaudig A, Krukemeier S, Eilers M, Strauss G, Welte K (2001). “C-mpl mutations are the cause of congenital amegakaryocytic thrombocytopenia”. Blood. 97 (1): 139–46. doi:10.1182/blood.V97.1.139. PMID 11133753.

[Freedman-6] Freedman MH, Estrov Z (1990). “Congenital amegakaryocytic thrombocytopenia: an intrinsic hematopoietic stem cell defect”. Am. J. Pediatr. Hematol. Oncol. 12 (2): 225–230. doi:10.1097/00043426-199022000-00020. PMID 2378417.

[pmid16351641-7] King S, Germeshausen M, Strauss G, Welte K, Ballmaier M (December 2005). “Congenital amegakaryocytic thrombocytopenia: a retrospective clinical analysis of 20 patients”. Br. J. Haematol. 131 (5): 636–44. doi:10.1111/j.1365-2141.2005.05819.x. PMID 16351641.

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