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06:27
Use of a Monocyte Monolayer Assay to Evaluate Fcγ Receptor-mediated Phagocytosis
Published on: January 2, 2017
Hemophagocytic syndromes
1Department of Hematology and Oncology, Children's Hospital, University of Hamburg, Martinistrasse 52, 20246 Hamburg, Germany. janka@uke.uni-hamburg.de
Blood Reviews
|June 26, 2007
Summary
Hemophagocytic lymphohistiocytosis (HLH) is a severe inflammatory condition characterized by fever, low blood counts, and enlarged organs. Early diagnosis and treatment are crucial for survival, as untreated HLH is often fatal.
Area of Science:
- Immunology
- Hematology
- Pediatrics
- Rheumatology
Background:
- Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome.
- Cardinal symptoms include prolonged fever, cytopenias, hepatosplenomegaly, and hemophagocytosis.
- While often genetic in children, adult HLH typically lacks a known immune defect.
Purpose of the Study:
- To describe the clinical presentation and diagnostic criteria of HLH.
- To highlight the importance of early recognition and timely intervention.
- To differentiate HLH from common infections and related conditions like macrophage activation syndrome.
Main Methods:
- Review of clinical symptoms and biochemical markers.
- Discussion of underlying immune dysfunction, particularly Natural Killer (NK) cell and Cytotoxic T-lymphocyte (CTL) function.
- Identification of common triggers and associated conditions such as infections and malignancies.
Main Results:
- Impaired NK cell and CTL function are hallmarks of both genetic and acquired HLH.
- Infections (especially herpes viruses) and malignant lymphomas are frequent triggers.
- Macrophage activation syndrome is a specific form of HLH in rheumatic diseases.
Conclusions:
- HLH can mimic common infections, necessitating high clinical suspicion.
- Prompt initiation of immunosuppressive/immunomodulatory therapy is vital for improving outcomes.
- Awareness of HLH diagnostic criteria is essential for life-saving treatment.
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