Hemapheresis refers to the selective removal of certain component(s) of the blood by the use of a machine specially designed for this purpose. The blood component may require removal because it may be diseased or may be present in excess. Therapeutic hemapheresis can be broken down with 4 general types of treatment approaches.
(a) Plasma exchange: The plasma of certain patients contains harmful, disease-causing components which must be removed and replaced by an isotonic albumin solution. For certain diseases, fresh frozen plasma (provided by the Blood Bank) is used as a replacement fluid. Diseases for which plasma exchange is beneficial are numerous and include many neurological diseases, (Myasthenia Gravis, Guillian-Barre Syndrome, etc.) and hematological diseases such as TTP, among others.
(b) Cytapheresis: In certain hematological disorders, the white blood count or platelet count is dangerously high, and these components can be selectively removed using leukapheresis or platelet-apheresis.
(c) LDL apheresis: In this procedure, the patient’s blood is filtered through a unique type of membrane which selectively removes the harmful plasma lipid components, leaving behind the beneficial lipids and all other healthy plasma constituents. As of 2002, we have two types of machines to perform LDL apheresis.
One is a unique machine (DALI) which was acquired by Hadassah in March 2000. It performs whole blood filtration using a special affinity column. The other machine separates the plasma and precipitates the LDL using altered pH and heparin (HELP). Two separate systems are needed to meet the specific requirements of all of our patients. We are at present one of 2 centers in Israel providing this service.
LDL apheresis is lifesaving in that it prevents or reverses atherosclerosis of individuals with hypercholesterolemia who for various reasons, are not able to be treated by medical therapy using cholesterol-lowering drugs. These patients are referred and followed closely by Professor Eran Leitersdorf, of the Internal Medicine “B” Department, who is a renowned specialist in lipid disorders.
(d) Extracorporeal Photopheresis: A novel type of therapy which was developed only within the last decade is extracorporeal photopheresis. The treatment was initially designed for patients with skin lymphomas who had malignant cells circulating in their blood as well as being present in the skin.
Since these diseases were often not responsive to systemic chemotherapy, a unique treatment was devised in which the patient's white blood cells (including the malignant cells) could be radiated outside the body of the patient. First the white blood cells are removed from the body by leukocytapheresis, and then a special photosensitizing medication (8-hydroxy-MOP) is injected into the blood collection bag. This medication renders the cells highly sensitive to ultraviolet irradiation.
The addition of the medication directly to the collection bag of white blood cells allows only a small dose of medication to be used, greatly reducing the possibility of any side effects. The bag of cells is then placed in a special machine which delivers a specific amount of ultraviolet radiation over a short period of time, about a half an hour. This causes damage to the malignant cells, which ultimately leads to their destruction. The last step in the treatment is retransfusing the radiated cells into the body of the patient, where they are removed by action of the immune system of the patient. This also stimulates the body to destroy the other malignant cells which were not removed and radiated, such as those located in the skin.
The therapy is often effective in treating the cutaneous lymphomas, which may be refractory to regular medical therapy. However, besides this type of direct cytotoxic application, there are many other potential uses for extracorporeal photopheresis. An important application of this therapy is in the treatment of patients who have received organ or bone marrow transplants. For example, this therapy has been found to prolong the survival of transplanted solid organs such as cardiac transplants, by preventing rejection. Similarly, lung transplant patients have been successfully treated for rejection with extracorporeal photopheresis. The treatment can also be used to successfully treat severe graft versus host disease after allogeneic bone marrow transplantation.
In short, this promising novel form of "extracorporeal photochemotherapy" has many therapeutic applications. We are proud to say that Hadassah Ein Kerem was the first hospital in Israel to perform this type of treatment and we have performed more of these procedures than any other center in Israel.
The hemapheresis unit is headed by Professor Deborah Rund. Mrs. Tova Schaap is the senior technician, and they both have nearly 2 decades of hemapheresis experience. Mrs. Schaap is exclusively dedicated to hemapheresis, and frequently travels abroad to keep up to date on the newest developments in this rapidly changing field. This has enabled Hadassah to remain at the forefront of apheresis treatment not only in Israel but in the world. The technician staff consists of highly trained medical technologists who undergo an extensive period of supervised training in the techniques of these various apheresis procedures. Two of our technicians are experienced cardiac intensive care nurses. They are indispensable for treating our cardiac patients who undergo LDL apheresis.
Referrals for therapeutic hemapheresis are made by the treating physician, by calling (02)6776696. The unit operates 5 days a week, 8:00 am. - 4:00 pm.
Emergency referrals are made by calling the same number or Professor Deborah Rund, or the Senior Hematologist on call through the Hadassah operator (02-6777111). There is a hemapheresis technician on call for emergencies 24 hours a day, 365 days a year.