View clinical trials related to Hemolysis.
Filter by:This study will try to determine what causes toxic side effects of stem cell transplantation, such as increased blood pressure, increased heart rate, decreased kidney function and abnormal heart rhythms. Stem cells are used to treat various diseases, including cancer, aplastic anemia and sickle cell disease. The cells may be given fresh to the patient or they may be preserved first with a chemical called DMSO and frozen for later use. Some stem cell transplant procedures include infusion of red blood cells along with the stem cells. This study will examine whether side effects of stem cell transplants are associated with the DMSO preservative in frozen cells or with hemoglobin (a protein released from defrosted red blood cells) or neither of these factors. Healthy volunteers and patients scheduled to receive a stem cell transplant may be eligible for this study. Candidates must be between 10 and 80 years of age. Transplant patients will undergo a stem cell transplant. The cells are infused through a catheter placed in a vein for the procedure. Depending on the patient s requirements, the infusion may or may not include red blood cells and may or may not contain DMSO. Healthy volunteers undergo a 4-hour saline infusion. The saline (water mixed with salt) is infused through a catheter (plastic tube) placed in a vein in the arm. In addition, all participants have the following tests and procedures: - Heart monitoring: Healthy volunteers wear a portable heart monitor, attached to the chest using four stickers, for 24 hours starting the morning of the infusion. Transplant patients wear the same device for 48 hours, starting the morning before the infusion. - Blood draws and urine collections before, during, just after and the morning after the infusion of saline or stem cells. - Heart ultrasound before, during or just after and the morning after the infusion. - Peripheral artery tonometry: A small cup is placed on one finger of each hand to measure blood flow in the finger. A blood pressure cuff is inflated around the lower arm and tight pressure is maintained for about 5 minutes.
The general objective of this study is to assess the efficacy and safety of Rituximab in the management of patients with refractory or relapsed thrombotic thrombocytopenic purpura-hemolytic uremic syndrome (TTP-HUS). There have been several case reports and case series describing the use of Rituximab in patients with TTP-HUS; however its use has not been studied in a large trial. It is hypothesized that Rituximab may ameliorate the severity of certain cases of TTP-HUS by decreasing the number of activity of B-cells which may result in decreased production of the ADAMTS13 protease inhibitor. Patients with TTP-HUS not responding to standard therapy or patients with relapsed disease may have particular benefit. Treatments that decrease the frequency of relapse or shorten the time to remission of TTP-HUS will be of benefit by decreasing the need for blood product support.
Treatment for patients with autoimmune destruction of blood cells is poor. The part of the body that fights infections is called the immune system and white blood cells (WBCs) are part of the immune system. Normally, a person's body creates WBCs to fight infections and eliminates WBCs which have stopped helping the body function. Patients with autoimmune destruction of blood cells have difficulty eliminating old WBCs. The abnormal WBCs build up and can damage other healthy cells, which can lead to anemia, fatigue, jaundice, internal bleeding, infection, and cancer. Few effective medications exist for treatment for patients with autoimmune cytopenias and those commonly used are fraught with side effects. Nevertheless, as scientific understanding of autoimmune diseases has improved, more directed and less toxic therapies are becoming available. A number of groups have been studying the efficacy of a medication called sirolimus in patients with autoimmune diseases. This medicine has been FDA-approved for over 20 years. Sirolimus is a medicine used in children with other diseases. Sirolimus works, in part, by eliminating old and abnormal WBCs. Our group and others have shown that sirolimus is effective in mice with autoimmunity and in children with a rare condition called Autoimmune Lymphoproliferative Syndrome (ALPS). We believe sirolimus will help children with autoimmune cytopenias. We believe it will improve their symptoms and make them less sick. We propose to study sirolimus in children with chronic and/or refractory autoimmune cytopenias.
To understand how AKI (Acute Kidney Injury) leads to chronic kidney disease so therapies can be found to alter the progression of events thereby significantly impacting the long-term outcomes of children who develop AKI.
This study will evaluate new treatments for people who have pulmonary hypertension, or high blood pressure in the lungs, caused by sickle cell anemia or thalassemia. Patients ages 18 and older with a diagnosis of sickle cell disease or thalassemia, who have mild to severe pulmonary hypertension, and who are not pregnant or breastfeeding may be eligible for this study. There are three stages in the study, with up to 200 participants in the screening. Patients will undergo pulmonary function tests, including those for asthma and measurement of oxygen levels in the arterial blood. They will have a chest X-ray, computed tomography (CT) scan of the lungs, ventilation perfusion lung scan to look for blood clots, echocardiogram, test to measure how far patients can walk in 6 minutes, nighttime oxygen measurement done while asleep, blood collection, magnetic resonance imaging (MRI) scan of the heart, and exercise test. About 3 to 4 days are needed for the tests, all of which can be done while patients are outpatients, except for the sleep study. For the CT scan, patients lie on a table while an X-ray beam takes images of the lungs and heart. The lung scan involves breathing of a small amount of a radioactive aerosol called Tc99m DTPA while pictures are taken of the lungs from various angles. Then an injection of albumin, a protein with a small amount of radioactivity, will be given, and more lung pictures will be taken. For the MRI scan, patients lie on a table that slides into a machine. A medication called gadolinium will be injected, to help improve images made through the scan. After the tests, patients will be admitted to the Clinical Center for 1 day. A small plastic catheter, or tube, will be placed in the vein of an arm. A longer catheter will go into a deeper vein (neck or leg), and a pulmonary artery catheter will be inserted to measure blood pressure in the blood vessels. Doctors will guide the catheter into the lung artery. Patients will be asked to pedal on a stationary bicycle while heart and lung pressure is measured. If pulmonary hypertension is present, patients will proceed to the second stage (up to 50 participants). While the catheter is still in place, patients will wear a face mask and breathe nitric oxide (NO) for 20 minutes. They will take 50 mg of sildenafil by mouth, and pressure in the heart and lungs will be monitored for about 4 hours. They will again receive NO for another 20 minutes. Blood samples will be taken, and the heart rhythm and pressure in the lungs will be monitored. Sildenafil can cause headache, flushing, and indigestion. Side effects of the lung scan involve allergic reactions to DTPA and albumin. Patients with an allergy to eggs should not have that test. Up to 25 patients can enter the third stage. They will breathe NO by using a tank of gas that delivers it through tubes to the nose, for a period of 6 weeks. They will continue taking sildenafil as previously prescribed and visit the clinic every 2 to 4 weeks for an echocardiogram, blood tests, and 6-minute walk test. After 6 weeks, patients will have catheterization of the heart again to measure pressure in the heart and lungs. Then NO will be stopped, and pressure in the lungs will be checked to see if NO has helped lower the blood pressure-and to make sure that the blood pressure does not increase when medication is stopped. Patients whose symptoms have improved as a result of breathing NO may wish to continue with that therapy.
This study will examine blood for factors that may cause or prevent diseases involving iron or red blood cells. Iron is an important nutrient for human health that is needed to produce red blood cells. Red blood cells carry oxygen to body tissues. A better understanding of iron and red blood cells may help lead to better treatment of several diseases including anemia. Patients of all ages with red cell abnormalities in the following categories may be eligible for this study: - Diseases with deficiency, overload or maldistribution of iron - Known red blood cell diseases, such as anemias and hemoglobinopathies - Red blood cell diseases of unknown cause, such as hemolysis of unknown cause - Red blood cell abnormalities with no overt clinical disease, such as hereditary persistence of fetal hemoglobin Participants undergo the following procedures: - Medical history - Physical examination - Standard medical tests related to the individual's iron or red blood cell condition Blood draw for the following purposes: - Testing for syphilis and for the hepatitis B and C, HIV, and HTLV-1viruses, and for a pregnancy test for women who can become pregnant - Research purposes. This blood is analyzed for genes, proteins, sugars, and fat molecules.
OBJECTIVES: I. Determine the effect of SYNSORB Pk therapy on mortality and frequency of severe extrarenal complications observed in children with acute stage E. coli-associated hemolytic uremic syndrome. II. Determine the effect of SYNSORB Pk therapy on the need for the duration of dialysis in these patients. III. Determine the effect of SYNSORB Pk therapy on the recovery of renal function and resolution of urinary abnormalities in these patients.
Platelets are particles found along with red and white blood cells in the blood that play a role in the process of blood clotting. Disorders affecting the platelets can lower the amount of platelets in the blood and put patients at risk of bleeding. The condition of low platelets is referred to as thrombocytopenia. Thrombocytopenia can be associated with a variety of diseases including cancer, leukemia, tuberculosis, or as a result of an autoimmune reaction. Autoimmune reactions are disorders in which the normal immune system begins attacking itself. Autoimmune thrombocytopenia (AITP) is a disorder of low blood platelet counts in which platelets are destroyed by antibodies produced by the immune system. Unfortunately, many patients with AITP do not respond to standard treatments for thrombocytopenia. Cyclophosphamide is a drug that works to suppress the activity of the immune system. Researchers believe that combining this drug with transplanted rescued blood stem cells may provide effective treatment for AITP. The purpose of this study is to explore the affordability and safety of this therapy for the treatment of AITP. The effectiveness of the therapy will be measured by the number of patients whose platelet levels rise greater than 100,000/m3. If this treatment approach appears affordable, this study will form the basis for a larger study to compare alternate treatment approaches.