Cryoglobulinaemia is relatively often associated with connective tissue diseases. Type II and type III cryoglobulinaemia, also known as mixed cryoglobulinaemia, are mainly associated with autoimmune diseases. From the clinical point of view it is most important to make the right differential diagnosis between rheumatoid arthritis, Sjögren’s syndrome and cryoglobulinaemia in a HCV infection because rheumatoid factors are present
in all of these diseases. The causes of cryoglobulinaemia, pathophysiology, evaluation of serum cryoglobulins, clinical manifestations and therapy are discussed in the presented paper.