Detection of B-cell populations with monotypic light chain expression in cerebrospinal fluid specimens from patients with multiple sclerosis by polychromatic flow cytometry.

Abstract

BACKGROUND:

Flow cytometric immunophenotyping is an established method for the detection of occult leptomeningeal disease in patients with aggressive B-cell non-Hodgkin lymphoma, and is increasingly being used in the evaluation of patients without an established diagnosis of lymphoma who present with signs and/or symptoms referable to the central nervous system. However, the specificity of flow cytometric immunophenotyping in the identification of monoclonal B-cell populations in cerebrospinal fluid (CSF) has not been systematically evaluated.

METHODS:

We searched a consecutive series of CSF specimens submitted to our laboratory for polychromatic (8-color) flow cytometric immunophenotyping between June, 2010 and December, 2012 for cases in which a B-cell population with monotypic immunoglobulin light chain expression was detected in patients without clinical or radiographic evidence of lymphoma.

RESULTS:

A B-cell population with monotypic light chain expression was identified in CSF specimens from three patients whose subsequent clinical and radiologic evaluation provided no evidence for lymphoma. In all three patients, a diagnosis of multiple sclerosis was ultimately rendered upon completion of the clinical evaluation.

CONCLUSIONS:

We conclude that the detection of a B-cell population with monotypic light chain expression in CSF by polychromatic flow cytometry is not diagnostic of occult leptomeningeal involvement by a B-cell non-Hodgkin lymphoma. Moreover, these findings suggest that monotypic B-cell populations detectable by polychromatic flow cytometry may be prevalent in patients with multiple sclerosis, and highlight the importance of clinicopathologic correlation in this application of polychromatic flow cytometry.

• Authors: Poopak Vafaii, Joseph A DiGiuseppe
• Journal: Cytometry. Part B, Clinical cytometry (Cytometry B Clin Cytom) Vol. 86 Issue 2 Pg. 106-10 (Mar 2014) ISSN: 1552-4957 [Electronic] United States
• PMID: 23818243 (Publication Type: Journal Article)
• Copyright: Copyright © 2013 Clinical Cytometry Society.

Chemical References

• Immunoglobulin Light Chains

Topics

• Adult
• B-Lymphocytes (cytology, immunology)
• Cerebrospinal Fluid (cytology, immunology)
• Female
• Flow Cytometry
• Humans
• Immunoglobulin Light Chains (biosynthesis, immunology)
• Immunophenotyping
• Male
• Multiple Sclerosis (diagnosis, immunology)
• Young Adult