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Updated: Jun 5, 2026
06:29
Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells
Published on: January 29, 2014
Extreme hypercomplementemia in the setting of mixed cryoglobulinemia
Bharath Manu Akkara Veetil1, Thomas G Osborn, Dean F Mayer
1Division of Rheumatology, Mayo Clinic, 200 First St SW, Rochester, MN 55905, USA. akkaraveetil.bharathmanu@mayo.edu
Clinical Rheumatology
|January 8, 2011
Summary
Extremely high levels of complement components C3 and C4 were observed in a patient with lymphoplasmacytic lymphoma. Despite unprecedented elevations, no organ damage occurred, challenging typical understandings of hypercomplementemia.
Area of Science:
- Immunology
- Hematology
- Clinical Medicine
Background:
- Complement components C3 and C4 are typically elevated in inflammatory conditions, reflecting immune system stimulation.
- Such elevations are not usually considered causative of organ injury.
- Extremely high levels are rare and typically associated with hematopoietic malignancies.
Observation:
- This report details a unique case of C3 elevation to 9.22 g/L (5x ULN) and C4 to 2.48 g/L (6x ULN).
- These unprecedented magnitudes of hypercomplementemia were observed in a patient with lymphoplasmacytic lymphoma.
- No adverse end-organ damage was noted despite the excessive complement levels.
Findings:
- Documented case of record-breaking C3 and C4 hypercomplementemia.
- Correlation of extreme hypercomplementemia with lymphoplasmacytic lymphoma.
- Absence of organ damage in the presence of severe hypercomplementemia.
Implications:
- Challenges the assumption that severe hypercomplementemia invariably leads to organ damage.
- Suggests potential for novel therapeutic targets or management strategies in lymphoplasmacytic lymphoma.
- Highlights the need for further research into the clinical significance of extreme hypercomplementemia.
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