Thrombosis at Unusual Sites: Focus on Myeloproliferative Neoplasms and Paroxysmal Nocturnal Hemoglobinuria

Patients with thrombosis thrombosis: (throm-BOE-suss) A blood clot (thrombus) that develops and attaches to a blood vessel. at an unusual site will need to be explored for rare causes of thrombosis. Two of these rare causes include myeloproliferative neoplasms (MPNs) and paroxysmal nocturnal hemoglobinuria paroxysmal nocturnal hemoglobinuria: (par-uk-SIZ-muhl nok-TURN-uhl hee-muh-gloe-buh-NYOOR-ee-uh) A rare and serious blood disease that causes red blood cells to break apart. Paroxysmal means sudden and irregular. Nocturnal means at night. Hemoglobinuria means hemoglobin in the urine. Hemoglobin is the red part of red blood cells. A… (PNH). It is important not to overlook these causes, since they require specific management, in addition to antithrombotic treatment (anticoagulants, antiplatelet agents). Unusual sites of venous thrombosis venous thrombosis: Blood clot in a vein include upper extremity veins, splanchnic veins, cerebral veins, and retinal veins, and unusual sites of arterial thrombosis include renal, adrenal, splenic and mesenteric arteries, and intracardiac and aortal locations. Suspicion for MPN and PNH should be raised if there are concomitant abnormalities, such as elevated or decreased blood cell counts or splenomegaly. Diagnosis of MPN and PNH should include JAK2V617F mutational screening as well as flow cytometric assessment of GPI-anchored proteins in the peripheral blood, respectively. Specific treatments for MPN may include phlebotomy or cytoreductive drugs such as hydroxyurea hydroxyurea: Hydroxyurea is in a class of medications called antimetabolites. Hydroxyurea treats cancer by slowing or stopping the growth of cancer cells in your body. It can be used alone or with other medications to treat a certain types of leukemias.  , anagrelide, pegylated interferon-alpha, or Janus kinase inhibitors. Drugs used for PNH treatment include terminal complement inhibitors, such as eculizumab eculizumab: Eculizumab (Soliris ®) is given as an IV into a vein at the doctor’s office or at a special center. The procedure usually takes about 35 minutes. You will probably get an IV once a week for the first 4 weeks. Starting in the 5th week, you will get a slightly higher dose of Soliris every 2 weeks. … and ravulizumab, as well as proximally acting inhibitors such as pegcetacoplan pegcetacoplan: EMPAVELI® is the first PNH treatment that binds to complement protein C3. It was approved by the Food and Drug Administration in May 2021 for treating adult patients with paroxysmal nocturnal hemoglobinuria (PNH). EMPAVELI is given skin (subcutaneously) by using the Empaveli injector or with an… or iptacopan iptacopan: FABHALTA, a complement factor B inhibitor, is the first oral medication approved to treat adults with paroxysmal nocturnal hemoglobinuria (PNH). It was approved by the U.S. Food and Drug Administration in December 2023. Fabhalta is taken twice a day in a capsule form. What is FABHALTA? … . Patients with MPN and PNH are at high risk for thrombosis during their entire lifetime and should thus be followed by specialists experienced in the care of these diseases.