Eosinophilia

This study will investigate how, why and under what conditions eosinophils (a type of white blood cell) become activated and will examine their function in immune reactions. Eosinophil counts often rise in response to allergies, asthma, and parasitic worm infections. They can also go up in uncommon autoimmune conditions and, rarely, in association with tumors. Elevated levels of these cells is called eosinophilia. Usually, eosinophilia causes no apparent symptoms, but in rare cases there may be local swelling and itching, allergic lung problems, heart disease or nerve damage caused by the release of toxic substances in these cells into body tissues. Patients 1 to 100 years of age with eosinophil counts greater than 750/ml or an abnormal accumulation of eosinophils in the skin or body tissues may be eligible for this study. All participants will have a thorough medical history, physical examination and blood tests. Depending on the person's age and symptoms, other diagnostic tests may be done, including specialized studies of the eye, lungs, skin, bone marrow, nerves or heart. This is not a treatment study, and no experimental treatments will be offered. Patients who require treatment will receive standard medical care. Certain other procedures may be requested solely for research purposes. All participants will be asked to donate extra blood for laboratory studies investigating how immune cells and other immune substances in the blood act to stimulate a rise in eosinophils. In addition, some participants may undergo one or more of the following: * Annual Follow-up evaluations - Physical examinations and blood tests to evaluate changes in the patient's condition and eosinophil counts over time. * Bone marrow biopsy and aspiration will be recommended during the initial evaluation, and in certain patients at other times when it is important to look directly at the newly developing cells in the bone marrow. For this procedure an area of skin and bone is anesthetized with xylocaine (an anesthetic similar to that used by dentists), and a very sharp needle is used to sample the bone marrow for evaluation. Bone marrow biopsy and aspiration can have side effects of pain and/or bleeding into the skin and soft tissues at the site of the procedure. Rarely the area at the biopsy site can become infected, and is treated with antibiotics. * Genetic testing: Some of the blood drawn from you as part of this study will be used for genetic tests. Genetic tests can help researchers study how health or illness is passed on to you by your parents or from you to your children. Any genetic information collected or discovered about you or your family will be confidential. * Leukapheresis (only patients 18 years and older) to collect large numbers of certain cells - In this procedure, whole blood is collected through a needle placed in an arm vein. The blood circulates through a machine that separates it into its components. The white cells are then removed and the rest of the blood is returned to the body, either through the same needle used to draw the blood or through a second needle placed in the other arm....

Eosinophils are a type of white blood cell. Elevated eosinophil levels can damage the heart, nerves, and other organs, in the syndrome known as hypereosinophilic syndrome (HES). Some individuals have a hereditary form of HES known as familial eosinophilia (FE). More research on the causation and mechanisms of HES is needed in order to design more effective and less toxic therapies. This study will investigate FE and its genetic causes, damage mechanisms, and disease markers (such as blood test abnormalities). It will enroll approximately 50 individuals (both adults and children) from a previously studied family with FE. This is a long-term study of indefinite duration. Participants will undergo yearly clinical examinations including medical history, physical examination, bloodwork, EKG, echocardiogram, and pulmonary function tests, with additional or more frequent examinations and tests as required. In addition, participants will donate blood and tissue for research purposes. Both adult and child participants will donate blood. At the initial evaluation, adult participants will donate bone marrow. During the study, some adult participants will also undergo a limited number of leukaopheresis sessions, in which blood is donated from one arm, the blood is separated into red blood cells and other components, and the red blood cells are returned into the donor's other arm.

Unexplained chronic hypereosinophilia (HE) and hypereosinophilic syndromes (HES) are heterogeneous regarding the organ involvements (heart, lungs, skin, .. or none), the evolutionary profiles, the response to treatments. Underlying mechanisms are largely unknown and may associate genetic predisposing factors (germinal ? somatic?), environmental factors (alimentation, tobacco use, hormones, infections, ..) The COHESion study aims to study all clinical and biological characteristics of HE/HES patients and their evolutionary profiles, with a focus on genetic factors and the mechanisms supporting transitory or persistant chronic HE/HES (in absence of any well identified extrinsic trigger like drugs, parasitosis, ..)

This phase II trial studies how well ruxolitinib works in treating patients with hypereosinophilic syndrome or primary eosinophilic disorders.

There are a few guidelines recommend about management of eosinophilia worldwide, most of guielines recommend a thorough history-taking and physical examination. Subsequently, investigations are requested based on suspected causes. In cases where parasite infection is suspected, particularly in developing countries, stool microscopy and serology are recommended. However, limitations such as low sensitivity of stool microscopy, the inconvenience of collecting multiple stool samples, and the high cost and unavailability of serology may arise. Consequently, some physicians opt for empiric anthelminthic regimens in managing eosinophilic patients, even without stool tests or if stool test results are normal. If subsequent complete blood count (CBC) results show a recovery of absolute eosinophil count, it is assumed that eosinophilia was caused by a parasite infection. While some studies demonstrate the efficacy and simplicity of this approach, there is a risk of overestimating parasite infection in eosinophilic patients, potential adverse drug reactions from unnecessary anthelminthic treatment, and the possibility of drug resistance due to inappropriate dosing. To address this gap, no study has yet compared the efficacy between specific anthelminthic treatment based on test results and empirical anthelminthic treatment in eosinophilic patients. Therefore, the investigators are conducting this study.