Case Presentation: A 31-year-old male with rheumatoid arthritis (RA), left central retinal vein occlusion (CRVO), and bilateral sensorineural hearing loss presented to the emergency department (ED) with abnormal labs. Several weeks prior, he was diagnosed with left CRVO after experiencing blurry vision. During that hospitalization, he was referred to hematology due to concern for hypercoagulable state versus hyperviscosity syndrome (HVS). Labs obtained by the hematologist revealed Na 121 mmol/L, bicarbonate 12 mmol/L, hemoglobin 9.6 g/dL, antithrombin III 67%, Protein S 31%, Protein C 62%. He was sent to the ED for hyponatremia and concern for HVS due to ongoing blurry vision, hearing loss, vertigo, and paresthesias. During this admission, labs revealed Na 120 mmol/L, hemoglobin 10.2 g/dL, ANA titer of 1:1280, rheumatoid factor (RF) antibody titer at 999, anti-cyclic citrullinated >250, immunoglobulin G 3559 mg/dL, C3 low at 11 mg/dL and C4 low at 2.9 mg/dL. He was admitted, and both hematology and rheumatology were consulted for hypercoagulability and elevated RF with concern for an RA flare, respectively. Further workup showed a serum viscosity level elevated at 12 and serum protein electrophoresis showed an elevated kappa/lambda ratio of 2.18 with the presence of a paraprotein. Bone marrow biopsy and skeletal survey were normal. The patient’s hyperviscosity was presumed to be from excess RF production. Management included intravenous methylprednisone 1 gram for three days and four sessions of plasmapheresis, which resulted in symptomatic improvement.
Discussion: This case describes the atypical association of HVS with RA. HVS is characterized by excess levels of proteins or cellular components that increase serum viscosity, which impairs tissue perfusion. The excess proteins come from another underlying disease process, commonly Waldenstrom’s Macroglobulinemia or multiple myeloma. Both diseases can cause HVS through a high tumor burden which produces large quantities of immunoglobulins. Rarely, RA has been associated with HVS through the excess production of RF. The most reported symptoms of RA-associated HVS include bleeding diathesis, neurological symptoms, heart failure, and constitutional symptoms. Our patient exhibited predominantly neurological symptoms. One study found that synovitis is present in 86% of RA patients diagnosed with HVS. Interestingly, our patient did not have clinically active synovitis. Although he was asymptomatic from that standpoint, his RF was elevated, suggesting active disease. This case emphasizes the importance of immunosuppression in asymptomatic RA patients as the underlying inflammatory process may be active even without symptoms. Hospitalists must recognize RA-associated HVS, as early identification and treatment are vital to avoid permanent complications. Immunosuppression can help prevent complications of RA, such as HVS, and help prevent recurrence.
Conclusions: Hyperviscosity syndrome is one of the few hematologic emergencies; it requires immediate intervention due to the risk of permanent neurologic complications. Our case emphasizes the need for urgent evaluation, diagnosis, and treatment of HVS by hospitalist teams to prevent such complications. RA-associated HVS is even more uncommon, and patients may not have clinically active RA upon presentation. Acute management of HVS with plasmapheresis, and immunosuppressive treatment for RA is necessary to prevent recurrence of HVS.