Retrospective cohort study of 148 patients with polyclonal gammopathy

• Objective: To quantify clinical conditions and laboratory values associated with moderate to marked polyclonal gammopathy. • Patients and Methods: Patient characteristics, laboratory correlates, evolving disease states, and survival of all patients seen at the Mayo Clinic, Rochester, Minn, during 1991 with a polyclonal gamma globulin level of 3.0 g/dL or higher were reviewed in this retrospective cohort study. • Results: One hundred forty-eight patients were identified (median age, 58 years; 59% female). In 130 patients (88%), only 1 diagnosis was identified. Liver disease was the most common single disease association in 79 (61%) of 130 patients, followed by connective tissue diseases in 28 (22%), chronic infections in 8 (6%), hematologic disorders in 6 (5 %), and nonhematologic malignancies in 4 (3 %). No difference in gamma globulin levels existed between groups. With a median follow-up of 67 months, 90 (63%) of 143 patients for whom follow-up was available were alive. By multivariate analysis, age, albumin concentration, disease group, and platelet count were predictive of survival. No patient developed myeloma or a clonal plasmaproliferative disorder. • Conclusion: Moderate to marked polyclonal gammopathy may reflect an underlying condition: liver disease, connective tissue disease, hematologic disorder, infection, or malignancy.