[Extraordinary high elevation of serum CA19-9 levels in an apparently healthy subject].
We studied the woman presenting extraordinarily high serum CA19-9 levels who did not have any disease that was known to result in elevation of the serum CA19-9 level. Her CA19-9 values in sera obtained by 16 determinations with the enzyme immunoassay (EIA) over a period of 7 years were from 820 U/ml to 1,310 U/ml (median 1,015 U/ml). The correlation was good between serum CA19-9 levels in this subject with the EIA and radio immunoassay (RIA). The molecular weight of CA19-9 was determined by high-performance liquid chromatography (TSK gel G4000 SWXL column). While the molecular weights of CA19-9 in each patient with pancreatic cancer, cholangioma, cholecystitis or pancreatitis that were used as controls, were greater than 1,000 kDa, the CA19-9 of this subject had the molecular weight of approximately 550 kDa. To further determine whether human immunoglobulin was involved in the elevation of CA19-9 in the serum of this subject, we investigated the effect of adding rabbit anti-human IgM, IgG and IgA sera to the serum of this subject, CA19-9 values were unaffected by these antisera. Thus, the data obtained from the absorption study indicated that an anti-idiotypic antibody against the anti-CA19-9 antibody is unlikely to be responsible for an elevation of CA19-9 in the serum of this subject.
Kaneko
Y
Y
Department of Clinical Pathology, Kobe City General Hospital.
Shibata
Y
Y
Nakamura
H
H
Kuroda
M
M
Nakazima
T
T
Kasakura
S
S
D000888:Antibodies, Anti-Idiotypic; D014408:Biomarkers, Tumor / Q000097:blood*; D018395:CA-19-9 Antigen / Q000097:blood* / Q000276:immunology; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D005189:False Positive Reactions; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007124:Immunoenzyme Techniques; D008875:Middle Aged; D008970:Molecular Weight
D000888:Antibodies, Anti-Idiotypic; D014408:Biomarkers, Tumor; D018395:CA-19-9 Antigen