10/04/2024 Important insight for Castleman disease patients: In a study published in the European Journal of Haematology, researchers presented four cases of patients with idiopathic multicentric Castleman disease (iMCD), a condition where an overactive immune system leads to inflammation and organ dysfunction, who were found to have extramedullary hematopoiesis (EMH). EMH, an abnormal phenomenon that occurs when blood cells are produced in sites other than the bone marrow, was observed in the lymph nodes of three patients and the spleen of one patient. Researchers believe that a protein called IL-6, which is involved in inflammation and has previously been linked to iMCD, might be responsible for this abnormal blood cell production. Though previously seen in mouse studies of MCD, this is the first study to report EMH in human iMCD cases, offering potential insights into what creates the characteristic features seen on the lymph nodes of CD patients.
