MLT/CAT (Multifocal Lymphangiomatosis and Thrombocytopenia or Cutaneous Angiomatosis and Thrombocytopenia)

MLT or CAT is a very rare condition described by 2 names coming from the two medical teams that discovered it simultaneously. It usually appears in early childhood and becomes chronic, with the highest severity at diagnosis and amelioration of symptoms as time goes. It is characterized by the appearance of multiple, small blood vessel abnormalities (with mixed venous and lymphatic elements) inside the bowel and the brain, a persistent skin rash and low platelet count (not enough cells in the blood stream to stop bleeding).

Signs and Symptoms

Characteristics may include:

  • Bleeding from the vascular anomalies inside the bowel that may be very severe and patients may require blood transfusions
  • Bleeding from the vascular anomalies inside the brain that may cause stroke and neurologic deficits
  • Multiple brownish - dark red patches on the skin (usually not bleeding)
  • Bleeding and bruising from small injuries and surgical interventions due to low platelet count
  • Anemia due to frequent bleeding
  • Usually the platelet count increases as the child grows and bleeding is less frequent


Unknown genetic cause for the condition.

Diagnosis and Tests

Diagnosis and tests may consist of:

  • Physical exam
  • Blood work (to check for anemia and platelet count)
  • Endoscopy and Colonoscopy for detection of vascular anomalies inside the bowel
  • Imaging
  • Magnetic Resonance Imaging (MRI) of the brain to screen or monitor vascular anomalies


Management of MLT/CAT involves a multidisciplinary team. Care may include:

  • Sclerotherapy or embolization – a solution is injected into the abnormal vessels to help make them shrink. It may target either the bleeding vessels inside the bowel (to be performed via an endoscopic procedure) or inside the brain
  • Surgical intervention to remove the bleeding vascular anomalies
  • Medical therapy with sirolimus – aimed at increasing the platelet count and preventing bleeding
  • Supportive care with blood products and preparation before any surgical or invasive procedure to reduce the risk of bleeding
  • Neurologic care after stroke, if needed