Kasabach-Merrit Phenomenon

Also known as: KMS, Hemangiomas with thrombocytopenia

What is Kasabach-Merrit syndrome?

Kasabach-Merritt syndrome (KMS) is also known as “hemangiomas with thrombocytopenia.” It is a combination of hemangioma, thrombocytopenia, and coagulopathy. It is a rare disease of infancy in which the thrombocytopenia (decreased platelet count) results from the hemangioma trapping and activating platelets, which in turn promotes further growth of the vascular tumor.

Bleeding problems can ensue and may be life-threatening. Laboratory testing including blood counts and clotting studies are important, as well as imaging studies and biopsy of the tumor when necessary.

What are the signs and symptoms for Kasabach-Merrit syndrome?

Some of the signs and symptoms include:

  • Visible cutaneous giant hemangioma or multiple smaller hemangiomas, usually on the extremities
  • Enlarged abdomen
  • Hepatomegaly
  • Petechiae, bruising, and bleeding
  • Painful lesions
  • Anemia

What are the treatment options for Kasabach-Merrit syndrome?

Generally, treatment of the underlying vascular tumor results in resolution of KMS. Surgical resection may provide a cure if it poses no threat to the patient. Other treatments include embolization and compression bandages to decrease the tumor’s blood supply, corticosteroids, alpha-interferon, and chemotherapy. Mortality rate is about 30%. Patients need close follow-up with dermatologists for residual cosmetic lesions.

This page was last updated on: July 27, 2021 04:28 PM

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Platelets (thrombocytes) are cells produced in the bone marrow that help the blood to clot by clumping together and forming a plug, at the site of a damaged blood vessel. Thrombocytopenia is the condition where there is a low platelet count (less than 150,000/microL) and this results in bleeding (hemorrhage) because the blood doesn't clot properly. Learn more

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