Sudden death caused by interaction between a macroglobulin and a divalent drug

Area of Science:

• Radiology
• Immunology
• Pathology

Background:

• Intravenous contrast media are essential diagnostic tools.
• Adverse reactions to contrast media can occur, ranging from mild to severe.
• Monoclonal gammopathies, such as macroglobulinemia, involve abnormal antibody production.

Purpose of the Study:

• To investigate the mechanism of intravascular precipitation caused by a specific divalent X-ray contrast medium.
• To determine the role of monoclonal macroglobulin in contrast-induced precipitation.
• To compare the effects of divalent and monovalent contrast media on macroglobulin.

Main Methods:

• Case study of a patient experiencing adverse reaction to ioglycamic acid.
• Passive transfer experiments in mice using patient serum and contrast media.
• In vitro binding studies of contrast media to purified IgM.

Main Results:

• Ioglycamic acid (divalent) induced intravascular precipitation and death in a patient with monoclonal macroglobulin.
• Mice in passive transfer experiments showed similar precipitation with ioglycamic acid.
• Acetrizoic acid (monovalent) bound to IgM but did not cause precipitation or adverse effects in mice.

Conclusions:

• Divalent X-ray contrast media can precipitate with monoclonal macroglobulins, leading to severe adverse events.
• The valency of the contrast medium is critical in determining its interaction with macroglobulins.
• Monovalent contrast media appear safer in the context of monoclonal gammopathies.