Monoclonal elevation of circulating IgG concentration

What it means

An increase in circulating immunoglobulins characterized by a single band in serum electrophoresis but not the broad diffuse band that characterizes a polyclonal increase in circulating immunoglobulins.

Monoclonal gammopathies are associated with a clonal process that is malignant or potentially malignant. In contrast, polyclonal gammopathies may be caused by any reactive or inflammatory process, and they usually are associated with nonmalignant conditions.

Rare diseases that can present with this1

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Monoclonal elevation of circulating IgG level