View clinical trials related to Anemia, Sickle Cell.
Filter by:This study will determine whether niacin can improve blood flow in people with sickle cell disease, in which abnormal red blood cells interfere with blood flow to cause the disease symptoms. Niacin, a drug that has been used to increase HDL (good cholesterol) levels, improves blood flow in people without sickle cell disease. This study will see if it can do the same in people with the disease. Patients with sickle cell disease between 18 and 65 years of age may be eligible for this study. Candidates are screened with a medical history, physical examination, blood tests, echocardiogram and 6-minute walk test of exercise capacity. Participants have the following baseline blood flow studies: - Flow-mediated dilation (FMD): An ultrasound picture of the artery in the forearm is obtained. A blood pressure cuff is then placed on the upper arm and inflated for 5 minutes. After the pressure cuff is released, the ultrasound is repeated. - Peripheral artery tonometry (PAT): A sensor is placed on the subject s finger. The sensor puts pressure on the finger and measures blood flow. - Standard forearm blood flow test: Small tubes are placed in the artery of the forearm at the inside of the elbow. Saline is infused into one tube. Pressure cuffs are applied to the wrist and upper arm. A strain gauge (rubber band device) is placed around the forearm. When the cuffs are inflated, blood flows into the arm, stretching the strain gauge, and the flow measurement is recorded. Blood samples are collected from the tube in the artery to measure blood counts, proteins and other chemicals. At various times, small doses of the following drugs are administered through the tube in the vein: - Sodium nitroprusside causes blood vessels to dilate and increases blood flow to the heart. - Acetylcholine causes blood vessels to dilate and slows heart rate. - LNMMA decreases blood flow by blocking the production of nitric oxide. Blood flow is measured after each dose of the different drugs. There are rest periods between injections of the different drugs. Pictures of the forearm are taken during the studies using an infrared camera and computer. -Drug Treatment. Participants are assigned to take three 4-week courses of niacin or placebo. They return to the Clinical Center at the following intervals from the time they start the test drug for followup: - Weeks 2, 6 and 10: Brief medical history, review of medication side effects and blood tests. - Weeks 4 and 8: Physical examination, brief medical history, review of medication side effects and blood tests, repeat FMD and PAT blood flow studies and 6-minute walk test. - Week 12: Same as weeks 4 and 8 plus standard blood flow studies and echocardiogram.
Recent clinical and experimental data indicate that statins have effects beyond cholesterol lowering that may be beneficial in sickle cell disease by protecting the vascular endothelium. Statins have been shown to attenuate endothelial dysfunction through their anti-inflammatory, anti-oxidant and anti-thrombotic properties. This phase I/II dose-escalating trial is designed to assess the safety and potential clinical efficacy of oral simvastatin (Zocor)in adolescents and adults with sickle cell disease (SCD).
The study will look at the risk factors for pulmonary hypertension (high blood pressure in the lungs) in children and adolescents with sickle cell anemia (SCA) and examine the role of hypoxia (oxygen shortage) in the disease. In patients with SCA, red blood cells become sickle-shaped and tend to form clumps that get stuck in blood vessels, blocking blood flow to the limbs and organs. Blocked blood vessels can cause pain, serious infections, and organ damage. Many patients with SCA also develop pulmonary hypertension. Children and adolescents with SCA or Chuvash polycythemia (another blood disorder that carries an increased risk for pulmonary hypertension) may be eligible for this study. Participants undergo the following procedures at the beginning (baseline) and end of the study: - History, physical examination and blood tests . - Echocardiography (ultrasound study of heart function). - Transcranial doppler (brain ultrasound study to measure brain blood flow). - Lung function tests. - 6-minute walk (measure of the distance covered in 6 minutes of walking). In addition, patients are followed by telephone or by clinic visits every 6 months for a review of their medical history and medications. A physical examination is also done at 12 months.
Sickle cell anemia and sickle cell thalassemia are frequent diseases among the israeli arab population. The purpose of this study is to assess the clinical characteristics of the patients in one arab village and the laboratory characteristics in the carriers of this gene based in the screening for pregnant women that is carried out in the population of northern Israel. The results can be useful in order to institute universal screening for sickle cell anemia in northern Israel.
Hydroxyurea was found to be a good treatment in adult patients with sickle cell anemia with significant decrease in the frequency of vaso-occlusive crises and other crises related to SCA. Several studies were published with relative short term follow up in pediatric and young adult age. The purpose of this study is to assess the long term follow up in a group of patients that initiated Hydroxyurea treatment in childhood.
Patients diagnosed as having hemoglobinopathies are exposed to serious bacterial infections, principally those patients that underwent splenectomy. Since the introduction of anti pneumococcal vaccine the incidence decreased significantly but other bacteria besides encapsulated bacteria takes place as principal cause of invasive infections. The purpose of this study is to analyse in a retrospective study the incidence of those infections in a group of patients suffering from thalassemia and sickle cell anemia treated in our clinic.
Sickle cell disease is an inherited blood disorder that affects red blood cells (RBCs). People with sickle cell disease frequently experience anemia, or a low number of RBCs. RBCs are responsible for carrying oxygen to the brain and other body tissues that need oxygen to function properly. The purpose of this study is to determine what changes, which were possibly caused by anemia, exist in the brains of individuals with sickle cell disease.
The purpose of this research study is to find out whether Placenta Growth Factor (PlGF) and related tests can predict the development of acute chest syndrome (ACS) in patients with sickle cell disease (SCD) during a period where patients are well and during admission to the hospital for an acute sickle event to see if these measures can predict the development of ACS. Understanding events precipitating ACS may lead to preventative and interventional therapies which will improve patient outcomes and quality of life.
This Phase 2a, multicenter, open-label, dose-escalation study is designed to assess the safety and biologic activity of daily oral administration of 4 escalating doses of sapropterin dihydrochloride over 16 weeks in subjects with sickle cell disease. During an optional extension phase, the study will assess the safety, tolerability, and efficacy of extended treatment with sapropterin dihydrochloride, for a total of up to 2 years; The extension phase of this study was terminated.
The study will be conducted at 15-20 US centers in a randomized, placebo-controlled, double-blind fashion. Enrollees will be hospitalized sickle cell disease (SCD) patients at-risk for acute chest syndrome (ACS) based on the presence of vaso-occlusive crisis (VOC), fever (T ≥38.0°C) and serum sPLA2 concentration ≥50 ng/mL.