Serum immunoglobulin free light chain measurements and heavy chain isotype usage provide insight into disease biology in patients with POEMS syndrome.
POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, skin changes) syndrome is a rare paraneoplastic syndrome in which nearly all patients have a monoclonal lambda restricted plasma cell disorder. We investigated whether patients with POEMS have abnormal serum immunoglobulin free light chain (FLC) ratios. Fifty patients with newly diagnosed POEMS syndrome were assessed. Cystatin C levels were measured to discern whether subclinical renal insufficiency could account for FLC elevations in the presence of a normal FLC ratio. Forty-five patients (90%) had elevated lambda FLC; however, only nine (18%) had abnormal FLC ratios. The rise in serum FLC of POEMS patients appeared to be multifactorial-both a function of subclinical renal insufficiency and polyclonal activation of medullary and extramedullary plasma cells. Those patients expressing a clonal IgA were more likely to have clonal plasmacytosis observed on iliac crest biopsy than those with IgG. In summary, serum immunoglobulin profiles are unique in POEMS syndrome as compared with other plasma cell disorders.
Department of Laboratory Medicine and Pathology, Mayo Clinic College of Medicine, Rochester, Minnesota, USA.
Trista
T
Stankowski-Drengler
Morie A
MA
Gertz
Jerry A
JA
Katzmann
Martha Q
MQ
Lacy
Shaji
S
Kumar
Nelson
N
Leung
Suzanne R
SR
Hayman
Francis
F
Buadi
Robert A
RA
Kyle
S Vincent
SV
Rajkumar
Angela
A
Dispenzieri
D000328:Adult; D000368:Aged; D001706:Biopsy; D002999:Clone Cells / Q000473:pathology*; D055316:Cystatin C / Q000097:blood; D005260:Female; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D006801:Humans; D007085:Ilium / Q000473:pathology; D007070:Immunoglobulin A / Q000097:blood*; D007074:Immunoglobulin G / Q000097:blood*; D007143:Immunoglobulin Heavy Chains / Q000097:blood*; D007147:Immunoglobulin Light Chains / Q000097:blood*; D007146:Immunoglobulin lambda-Chains / Q000097:blood; D008297:Male; D008875:Middle Aged; D016878:POEMS Syndrome / Q000097:blood* / Q000276:immunology; D010950:Plasma Cells / Q000473:pathology*
C525030:CST3 protein, human; D055316:Cystatin C; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007146:Immunoglobulin lambda-Chains