IgM-Associated Cryoglobulinaemia

Cryoglobulinaemia is characterised by serum immunoglobulins that precipitate at temperatures below 37 °C and redissolve on warming. Monoclonal IgM immunoglobulin can be associated with type I and II cryoglobulinaemia with underlying Waldenström macroglobulinemia, monoclonal gammopathy of undetermined significance, or another non-Hodgkin lymphoma. In this research, we review the clinical characteristics of monoclonal IgM-associated cryoglobulinaemia and suggest a management approach for addressing them. Laboratory testing is critical as even a minimal amount of measurable cryoglobulin may result in symptoms. Accurate detection of cryoglobulins may be challenging, care must be taken with preanalytical variables, and repeated testing of monoclonal protein and cryoglobulins is indicated if clinical suspicion is high. Presentations range from asymptomatic to showing multisystem involvement, meaning that careful evaluation of the features and a thorough interrogation of organ systems and the underlying clone are critical. Immediate management is required for clinical red-flag features. Due to their rarity, data to inform treatment decisions are scant and collaborative research is imperative must be conducted to aid researchers in efforts to define optimal treatment strategies.