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Ex Vivo Infection of Human Lymphoid Tissue and Female Genital Mucosa with Human Immunodeficiency Virus 1 and Histoculture
Published on: October 12, 2018
[How should an immunodeficiency be explored?]
1Laboratoire d'immunologie pédiatrique, hôpital Necker-Enfants Malades AP-HP, 149, rue de Sèvres, 75743 Paris, France. ledeist@necker.fr
Insights
Simple blood tests and clinical evaluation help diagnose immunodeficiency. Early identification of lymphopenia and neutropenia guides further specific testing for immune disorders.
Area of Science:
- Clinical Immunology
- Pediatric Hematology
Context:
- Immunodeficiency diagnosis requires careful interpretation of early laboratory findings.
- Physiological variations in young children can complicate initial assessments.
Purpose:
- To outline essential initial investigations for suspected immunodeficiency.
- To highlight the diagnostic value of blood cell counts and immunoglobulin levels.
Summary:
- Lymphopenia, indicating cellular immunity deficits, is often missed in young children due to normal hyperlymphocytosis.
- Neutropenia below 500/mm3 is a significant clinical sign of potential immune compromise.
- Serum immunoglobulin (IgG, IgA, IgM) levels are interpretable after 4-5 months of age.
- Combined with medical history and clinical exam, these simple tests direct further specialized immunodeficiency investigations.
Impact:
- Facilitates earlier and more accurate diagnosis of primary immunodeficiencies.
- Improves patient outcomes by enabling timely targeted therapies.
- Reduces unnecessary investigations by guiding clinicians toward specific diagnostic pathways.
Abstract:
When immunodeficiency is suspected, simple investigations allow to direct the diagnosis. Blood cell count brings essential elements: the lymphopenia, signing a deficit of cellular immunity, is often ignored because of the physiological hyperlymphocytosis of the young child. Only a neutropenia lower than 500/mm3 could be responsible for obvious clinical signs. The level of the serum immunoglobulins IgG, IgA, and IgM becomes interpretable only after the age of 4-5 months. In most of the cases, all the elements brought by these simple laboratory investigations jointly to those brought by the medical history and the clinical examination make it possible to target the more specific investigations required in a second time, according to the type of evoked immunodeficiency.
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