Saturday April 26 , 2008
Regarding Thrombocytosis - 2
Continuing our theme from yesterday on thrombocytosis


Q: Although thrombocytosis seems to cause more thrombotic symptoms, than why GI bleed is one of the most common presenting symptom?

A; This is true that thrombosis is the basis of most symptoms, particularly with a platelet count greater than 1 million/mL. Thrombosis of large veins and arteries is common and may result in occlusion of the leg, coronary, and renal arteries. Other arteries may be involved. Symptoms from venous thrombosis of the splenic, hepatic, or leg and pelvic veins may develop. Priapism is a another known complication. Pulmonary hypertension may result from pulmonary vasculature occlusion.

The gastrointestinal tract is the common site of bleeding complications due to duodenal arcade thrombosis, resulting in sloughing of the duodenal mucosa and GI bleed. Similarly sloughing of mucosa at other sites may cause bleeding too like eyes, gums, urinary tract and possibly brain.

Another cause of bleeding could be an acquired von Willebrand's deficiency particularly with extreme thrombocytosis, ie, more than 1.5 million platelets/μL.