Type II cryoglobulinemia in a patient with chronic lymphocytic leukemia/small lymphocytic lymphoma and Sjögren's disease.

Type II cryoglobulinemia is a rare disorder characterized by abnormal immunoglobulins (Igs) precipitating in the blood at low temperatures and redissolving upon warming. Sjogren's disease (SjD) is an autoimmune disorder involving secretory gland malfunction that leads to persistent dryness of the mouth and eyes. Here, we report the case of a 61-year-old woman with a 7-year history of SjD who was diagnosed with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). However, her complicated clinical features could not be sufficiently explained by this disease alone. Immunofixation electrophoresis revealed monoclonal IgM-κ and polyclonal IgG-κ. The presence of precipitated cryoglobulin and elevated rheumatoid factor levels confirmed a diagnosis of type II cryoglobulinemia for this patient. To the best of our knowledge, this case represents the first report of a patient with CLL/SLL, SjD, and type II cryoglobulinemia, which increased our understanding of immune system-related disorders. Because certain similar mechanisms are involved in the pathogenesis of these three diseases, a combination treatment of rituximab, ibrutinib, and dexamethasone resulted in a favorable prognosis for this patient.