Creatine phosphokinase-linked immunoglobulin associated with hypokalemic myopathy.
We present three women with hypokalemic myopathy in whom serum creatine phosphokinase (CPK) was bound to serum immunoglobulin (macro-CPK). In all three cases, CPK isozyme electrophoresis demonstrated an extra CPK band between CPK-MM and CPK-MB. The bound immunoglobulins were identified as IgA/A-kappa and lambda, IgA-lambda and IgA-kappa and lambda, respectively. In all cases, histological examination of the biopsied muscles revealed necrotic and/or regenerating fibers. In each patient, potassium replacement therapy returned the macro-CPK as well as the marked elevations of serum muscle enzymes to normal. Taken together with other recent reports, our findings suggested that CPK-immunoglobulin binding may be related to the emergence of pathophysiology of hypokalemic myopathy.
Hoshino
J
J
Second Department of Internal Medicine, Gunma University School of Medicine, Maebashi.
Arai
H
H
Fukusato
T
T
Nakamura
T
T
Nushiro
N
N
Sato
K
K
Sakamaki
T
T
Murata
K
K
D000368:Aged; D001665:Binding Sites; D001706:Biopsy; D003402:Creatine Kinase / Q000097:blood*; D005260:Female; D006801:Humans; D007008:Hypokalemia / Q000097:blood* / Q000473:pathology / Q000628:therapy; D007070:Immunoglobulin A / Q000097:blood*; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism / Q000473:pathology*
D007070:Immunoglobulin A; D003402:Creatine Kinase