Hyperviscosity syndrome


  • Increased serum viscosity due to:
  • Symptoms arise from poor capillary flow and organ congestion

Clinical Features

Differential Diagnosis

Detailed differential can be found on each page

Oncologic Emergencies

Related to Local Tumor Effects

Related to Biochemical Derangement

Related to Hematologic Derangement

Related to Therapy



  • CBC, coags, type and screen, chem 10
  • Urinalysis
  • CT head if neuro symptoms
  • CXR
  • Consider initiating inpatient testing with: Total protein, albumin, SPEP, UPEP, IgA, IgG, IgM
  • Note: ABGs might have SaO2 vs. SpO2 discrepancies
    • Causing spurious hypoxemia on ABG, with low PaO2 (as opposed to dyshemoglobinemia)
    • Due to "leukocyte larceny," "platelet larceny"[1][2][3]
    • Excessive O2 consumption by WBCs or platelets following blood sample collection


Symptoms of hyperviscosity can appear when one of the following occur:

  • Red cell mass > 25% of normal[4]
  • Platelets >600,000/µL[5]
  • Leukocytosis >100,000
  • Serum viscosity >4-5cP (normal 1.4-1.8cP)[6] or Globulin gap (Total protein - albumin) > 4


  • ABCs
  • IVF, supportive care
  • Ig mediated/Dysproteinemia
  • Leukostasis
    • Leukapheresis
  • Thrombocytosis
    • Plateletpheresis
    • Consider ASA
  • Polycythemia
    • Phlebotomy
  • If pheresis is not unavailable, phlebotomize 2-3 units, give 2-3 L IVF


  • Typically require admission if symptomatic
  • Hem/Onc consult

See Also

External Links


  1. Mehta A, Lichtin AE, Vigg A, Parambil JG. Platelet larceny: spurious hypoxaemia due to extreme thrombocytosis. Eur Respir J. 2008 Feb;31(2):469-72.
  2. Sacchetti A, Grynn J, Pope A, Vasso S. Leukocyte larceny: spurious hypoxemia confirmed with pulse oximetry. J Emerg Med. 1990 Sep-Oct;8(5):567-9.
  3. Lele AV, Mirski MA, Stevens RD. Spurious hypoxemia. Crit Care Med. 2005 Aug;33(8):1854-6.
  4. Pearson TC and Messinezy M. The diagnostic criteria of polycythaemia rubra vera. Leuk Lymphoma. 1999; 22 (1):87-93.
  5. Murphy S et al. Diagnostic criteria and prognosis in polycythemia vera and essential thrombocythemia. Semin Hematol. 1999; 36(1):9-13.
  6. Mehta J and Singhal S. Hyperviscosity syndrome in plasma cell dyscrasias. Semin Thromb Hemost. 2003; 29(5):467-471.