Antiphospholipid syndrome, monoclonal gammopathy, and cryoglobulinemia overlap leading to recurrent cutaneous microvascular thrombosis: A case report and retrospective cohort study

Abstract Antiphospholipid syndrome (APS), cryoglobulinemia, and monoclonal gammopathies are variably accompanied by thrombotic complications. We describe a patient with recurrent skin microvascular thrombosis, APS, cryoglobulinemia, marginal zone lymphoma, and IgMκ monoclonal gammopathy, responsive to chemoimmunotherapy. The cryoglobulin fraction contained the IgMκ paraprotein, while antiphospholipid antibodies (aPL) were predominantly in the cryosupernatant. A retrospective analysis of aPL‐positive patients in our institution showed that 8.1% co‐expressed monoclonal gammopathy. These overlap patients had thrombotic complications and most had recurrences. Patients with multiple gammopathies of thrombotic significance may have several autoantibodies and constitute a high‐risk group.