Abstract

AIMS
A review of practice to determine whether serum-free light chain (SFLC) assays are helpful in detecting underlying clonal B-cell disorders or amyloidosis in patients with primary antibody deficiency (PAD) and recurrent infection.
METHODS
SFLC were assayed by nephelometry (BN2 nephelometer, Siemens; FREELITE assay, Binding Site). We reviewed SFLC test results recorded in our regional laboratory over a 4-year time period; 20 adults with PAD were identified as having been tested on at least two occasions.
RESULTS
Of 20 patients, 4 with PAD had abnormal serum-free kappa/lambda (K/L) ratios but no evidence of B-cell clonality. We also found extremely low levels of kappa and or lambda (below the limits of reliable detection) in 19/20 PAD cases (mostly common variable immunodeficiency), such that in many, ratios were not calculable.
CONCLUSIONS
The data suggest that the abnormal ratios are generated by an inability to produce and/or secrete SFLCs, particularly kappa FLC. In this small initial study, we seek to highlight PAD cases where a suspicious K/L ratio, typically with very low absolute quantities of SFLCs, most likely points to B-cell dysfunction, rather than to B lymphocyte clonality.

Links

Publisher Full Text

Authors

Unsworth DJ, Wallage MJ, Sarkar E, Lock RJ

Institution

Department of Immunology and Immunogenetics, Pathology Sciences, North Bristol NHS Trust, Southmead Hospital, Bristol, UK. Joe.Unsworth@nbt.nhs.uk

Source

Journal of clinical pathology 65:12 2012 Dec pg 1128-31

MeSH

Adolescent
Adult
Aged
Antibodies
B-Lymphocytes
Female
Humans
Immunoglobulin kappa-Chains
Immunoglobulin lambda-Chains
Immunologic Deficiency Syndromes
Male
Middle Aged

Pub Type(s)

Journal Article
Research Support, Non-U.S. Gov't

Language

eng

PubMed ID

23002283