Hyperviscosity Syndrome Clinical Presentation

Updated: Sep 09, 2021
  • Author: Thomas J Hemingway, MD, FACEP; Chief Editor: Barry E Brenner, MD, PhD, FACEP  more...
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The clinical presentation of hyperviscosity syndrome consists principally of the triad of mucosal bleeding, visual changes, and neurologic symptoms. [4] Constitutional symptoms and cardiorespiratory symptoms also contribute to the clinical presentation.

The tendency to bleed is the most common manifestation of hyperviscosity syndrome. Patients may present with any of the following:

  • Spontaneous gum bleeding
  • Epistaxis
  • Rectal bleeding
  • Menorrhagia
  • Persistent bleeding after minor procedures

Visual changes range from blurred vision to vision loss. Neurologic manifestations are frequent and varied, and may include the following:

  • Vertigo
  • Hearing loss
  • Paresthesias
  • Ataxia
  • Headaches
  • Seizures
  • Somnolence progressing to stupor and coma

Other manifestations may include heart failure, shortness of breath, hypoxia, fatigue, and anorexia. In fact, the clinician should have a high index of suspicion for hyperviscosity syndrome in patients with unexplained coma/altered mental status or unexplained shortness of breath, especially in those with an underlying hematologic disorder. 

Blood hyperviscosity plays a role in the pathogenesis of several cardiovascular diseases, including hypertension, atherosclerosis,and the metabolic syndrome. [9]



Physical findings are related to the major organ systems involved, as follows:

  • Bruises, epistaxis, or gum bleeding may be noted

  • Ophthalmic examination may reveal decreased visual acuity, dilated retinal veins, "sausage-linked" or "boxcar segmentation" of the retinal veins, or retinal hemorrhages [10]

  • Neurologic examination may reveal various abnormalities, including diminished mental status, confusion, ataxia, or nystagmus

  • Cardiopulmonary examination may reveal signs of congestive heart failure with volume overload (rales, lower extremity edema, elevated jugular venous pressure, and hypoxia)



Increased serum viscosity usually results from increased circulating serum immunoglobulins and can be seen in Waldenström macroglobulinemia, multiple myeloma, cryoglobulinemia, and Sjögren syndrome. [11, 12]

Less commonly, the hyperproliferative blood cell disorders such as the leukemias, myeloproliferative diseases, polycythemia, or thrombocytosis may be implicated for the increased viscosity caused by proliferation of their respective cellular components.