Spontaneously occurring antibodies to parathyroid hormone.
A 76-yr-old female with acute pancreatitis and a normal/borderline elevated serum calcium level was found to have an elevated immunoreactive circulating PTH concentration using a C-terminal assay. This high PTH concentration misled the attending physicians and resulted, in retrospect, in an unnecessary neck exploration. When the patient's serum was examined it was found to contain a binding component that bound both C-terminal and PTH-(1-84). This binding component was not retained on a Sep-Pak column and was precipitated by antiserum directed against human immunoglobulin M. The presence of circulating anti-PTH immunoglobulin M explains the apparently high PTH concentrations measured by RIA. The antibodies occurred spontaneously. To the best of our knowledge, this phenomenon has not previously been described.
Wilkinson
M
M
Department of Endocrinology, Royal North Shore Hospital, St. Leonards, New South Wales, Australia.
McElduff
A
A
Wilson
J
J
Haber
P
P
Freeman
A
A
Robertson
M
M
Mathews
P
P
D000208:Acute Disease; D000368:Aged; D000906:Antibodies / Q000276:immunology*; D001667:Binding, Competitive; D002118:Calcium / Q000097:blood; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D007075:Immunoglobulin M; D010195:Pancreatitis / Q000150:complications; D010279:Parathyroid Diseases / Q000175:diagnosis; D010281:Parathyroid Hormone / Q000097:blood / Q000276:immunology*
D000906:Antibodies; D007075:Immunoglobulin M; D010281:Parathyroid Hormone; D002118:Calcium