Esta página se tradujo automáticamente y no se garantiza la precisión de la traducción. por favor refiérase a versión inglesa para un texto fuente.

Etiología, patogenia e historia natural de la linfocitopenia CD4+ idiopática

Background:

  • Idiopathic CD4+ lymphocytopenia (ICL) is a condition in which there is a decreased level of CD4+ lymphocytes (a type of white blood cell), which can lead to opportunistic infections or autoimmune disorders and diseases.

Objectives:

  • To characterize the natural history with regard to CD4+ T cell count and onset of infection, malignancy, and autoimmunity.
  • To describe the immunological status of patients affected by ICL while providing the best possible standard therapy to eradicate opportunistic infections.
  • To establish the timeline of CD4 lymphocytopenia, with particular focus on defining subgroups of patients according to the decline, stabilization, or rise of CD4+ T cell counts over time.
  • To characterize the opportunistic infections that occur in ICL patients at microbiologic and molecular levels.
  • To characterize the immunophenotype and possible genetic immunodeficiency causes of ICL.
  • To determine whether measurable immunologic parameters correlate with the development of opportunistic infections or other comorbidities such as lymphoma in patients with ICL.
  • To determine whether there is any association between ICL and autoimmunity.
  • To determine CD4+ T cell turnover, survival, functionality, and cytokine responsiveness in ICL patients.

Eligibility:

  • Patients 2 years of age and older with an absolute CD4 count less than 300 in children 6 years or older and adults or less than 20% of T cells in children younger than 6 on two occasions at least 6 weeks apart.
  • Patients with negative results of HIV testing by ELISA, Western Blot, and viral load.
  • Patients must not have underlying immunodeficiency conditions, be receiving cytotoxic chemotherapy (anti-cancer drugs that kill cells), or have cancer.

Design:

  • At the initial visit to the National Institutes of Health, the following evaluations will be conducted:
  • Personal and family medical histories.
  • Physical examination, including rheumatology evaluation and other consultations as medically indicated (e.g., dermatology, pulmonology, ophthalmology, imaging studies).
  • Blood samples for analysis of red and white blood cell counts, liver function, immune hormones, and antibody and autoantibody levels, white blood cell growth and function, and DNA.
  • Urinalysis and urine pregnancy testing for female patients of childbearing age.
  • Evaluation and treatment of active infections as medically indicated, including biopsies, buccal swabs, pulmonary function tests, and imaging studies.
  • Follow-up visits will take place approximately every 12 months or more frequently if indicated, and will continue for a minimum of 4 years and a maximum of 10 years.
  • Evaluations at follow-up will include blood samples (i.e., CBC with differential, biochemical profile, HIV testing, etc.) and urinalysis and rheumatology consults.

Descripción general del estudio

Descripción detallada

Idiopathic CD4+ lymphocytopenia (ICL) is a disorder characterized by decreased numbers of circulating CD4+ T lymphocytes in the absence of known causes of CD4+ lymphocytopenia. ICL is defined as an absolute CD4+ T cell count of less than 300 cells/microL in a patient with no human immunodeficiency virus infection or known immunodeficiency syndrome. The causes and frequency of the disorder remain unknown. The condition is typically diagnosed when patients present with a serious infection. In this natural history protocol, we will evaluate patients with CD4+ T cell counts below 300 cells/microL. We propose to follow 300 ICL patients for a minimum of 4 and maximum of 20 years, with a particular focus on the association between ICL and autoimmune disease. In addition to the ICL patients, we will enroll blood relatives and household contacts to better understand pathogenesis and etiologies of the syndrome. We will collect blood and other tissues for immunologic, rheumatologic, and genetic testing in an effort to identify and understand the underlying defects that cause ICL and follow its course in a cohort of patients who will receive best standard therapy for opportunistic infections.

Tipo de estudio

De observación

Inscripción (Estimado)

950

Contactos y Ubicaciones

Esta sección proporciona los datos de contacto de quienes realizan el estudio e información sobre dónde se lleva a cabo este estudio.

Estudio Contacto

  • Nombre: Irini Sereti, M.D.
  • Número de teléfono: (301) 496-5533
  • Correo electrónico: isereti@niaid.nih.gov

Ubicaciones de estudio

    • Maryland
      • Bethesda, Maryland, Estados Unidos, 20892
        • Reclutamiento
        • National Institutes of Health Clinical Center

Criterios de participación

Los investigadores buscan personas que se ajusten a una determinada descripción, denominada criterio de elegibilidad. Algunos ejemplos de estos criterios son el estado de salud general de una persona o tratamientos previos.

Criterio de elegibilidad

Edades elegibles para estudiar

18 años y mayores (Adulto, Adulto Mayor)

Acepta Voluntarios Saludables

Sí

Géneros elegibles para el estudio

Todos

Método de muestreo

Muestra no probabilística

Población de estudio

Adults with idiopathic CD4+ lymphocytopenia (ICL) who have CD4 <300/microliters or < 20% of total T cells and their blood relatives and household contacts.

Descripción

  • ICL PARTICPANT INCLUSION CRITERIA:

To be eligible for this study, patients must satisfy all of the following inclusion criteria:

  1. Age greater than or equal to 18 years
  2. Absolute CD4 count < 300 cells/microL or < 20% of total T cells on at least two occasions at least 6 weeks apart
  3. Ongoing care by a referring primary care physician
  4. Willingness to allow storage of blood and tissue samples for future analysis

ICL PARTICPANT EXCLUSION CRITERIA:

Patients will be ineligible for this study if they satisfy any of the following criteria:

  1. Known infection with HIV-1, HIV-2, or human T-cell lymphotropic viruses (HTLV-1 or HTLV-2) as demonstrated by enzyme-linked immunosorbent assay (ELISA) and western blot and/or viral load testing
  2. Known underlying immunodeficiency syndrome other than ICL
  3. Evidence of active malignancy
  4. Receipt of medications, herbal substances, or biologic agents known to diminish the CD4+ count within 30 days of when the CD4+ lymphocytopenia was detected
  5. Any condition that in the judgment of the investigators would place the subject at undue risk or compromise the results of the study.

BLOOD RELATIVE INCLUSION CRITERIA:

To be eligible for study participation as a blood relative, subjects must be greater than or equal to 18 years of age and be a blood relative of an individual who meets or has met the CDC criteria for ICL.

HOUSEHOLD CONTACT INCLUSION CRITERIA:

To be eligible for study participation as a household contact, subjects must be greater than or equal to18 years of age and live within the same household as an ICL subjects participating in this protocol. Blood relatives who are household contacts are eligible to participate.

Plan de estudios

Esta sección proporciona detalles del plan de estudio, incluido cómo está diseñado el estudio y qué mide el estudio.

¿Cómo está diseñado el estudio?

Detalles de diseño

  • Modelos observacionales: COHORT
  • Perspectivas temporales: PROSPECTIVE

Cohortes e Intervenciones

Grupo / Cohorte
Blood Relatives

Blood Relatives of ICL subjects

Household Contacts

Household contacts of ICL subjects

ICL Subjects

Patients with confirmed idiopathic CD4 lymphocytopenia

¿Qué mide el estudio?

Medidas de resultado primarias

Medida de resultado
Medida Descripción
Periodo de tiempo
CD4 <300/microliters or < 20% of total T cells and their blood
Periodo de tiempo: Baseline and annually

To further characterize the natural history of ICL while also investigating the genetic, environmental, and immunologic features of the condition.

Baseline and annually

Medidas de resultado secundarias

Medida de resultado
Medida Descripción
Periodo de tiempo
Determine CD4+ T cell turnover, survival, functionality and cytokineresponsiveness in selected ICL patients.
Periodo de tiempo: Baseline and annually

Collection of research blood (PBL, serum and plasma) for storage

Baseline and annually
Investigate ICL immune cell homeostasis and trafficking by immunologic studies including tissue biopsies and the utilization of ahumanized mouse model.
Periodo de tiempo: Baseline and annually

Collection of research blood (PBL, serum and plasma) for storage

Baseline and annually
Establish the prognosis of CD4 lymphocytopenia, with particular focus on defining subgroups of patients according to the decline, stabilization, or rise of CD4+T cell counts over time.
Periodo de tiempo: Baseline and annually

Collection of research blood (PBL, serum and plasma) for storage

Baseline and annually
Determine whether measurable immunologic parameters correlate with the development of opportunistic infections or other co-morbidities
Periodo de tiempo: Baseline and annually

Determine whether measurable immunologic parameters correlate with the development of opportunistic infections or other co-morbidities such as lymphoma in patients with ICL. Investigate the associations between idiopathic CD4+ lymphocytopenia and autoimmunity.Collection of research blood (PBL, serum and plasma) for storage

Baseline and annually
Determine the relationship between ICL and the microbiome.
Periodo de tiempo: Baseline and annually

Collection of rectal swab and dietary questionnaire

Baseline and annually

Colaboradores e Investigadores

Aquí es donde encontrará personas y organizaciones involucradas en este estudio.

Investigadores

  • Investigador principal: Irini Sereti, M.D., National Institute of Allergy and Infectious Diseases (NIAID)

Publicaciones y enlaces útiles

La persona responsable de ingresar información sobre el estudio proporciona voluntariamente estas publicaciones. Estos pueden ser sobre cualquier cosa relacionada con el estudio.

Publicaciones Generales

Fechas de registro del estudio

Estas fechas rastrean el progreso del registro del estudio y los envíos de resultados resumidos a ClinicalTrials.gov. Los registros del estudio y los resultados informados son revisados ​​por la Biblioteca Nacional de Medicina (NLM) para asegurarse de que cumplan con los estándares de control de calidad específicos antes de publicarlos en el sitio web público.

Fechas importantes del estudio

Inicio del estudio (Actual)

13 de julio de 2009

Fechas de registro del estudio

Enviado por primera vez

20 de marzo de 2009

Primero enviado que cumplió con los criterios de control de calidad

20 de marzo de 2009

Publicado por primera vez (Estimado)

23 de marzo de 2009

Actualizaciones de registros de estudio

Última actualización publicada (Actual)

16 de octubre de 2026

Última actualización enviada que cumplió con los criterios de control de calidad

15 de octubre de 2026

Última verificación

8 de enero de 2026

Más información

Esta información se obtuvo directamente del sitio web clinicaltrials.gov sin cambios. Si tiene alguna solicitud para cambiar, eliminar o actualizar los detalles de su estudio, comuníquese con register@clinicaltrials.gov. Tan pronto como se implemente un cambio en clinicaltrials.gov, también se actualizará automáticamente en nuestro sitio web. .

Suscribir