title: Abnormal clot retraction, altered fibrin structure, and normal platelet function in multiple myeloma.
abstract: Clot retraction, measured by serum expression, is absent in some cases of multiple myeloma. Decreased clot retraction has been attributed to platelet dysfunction. A new instrument allows simultaneous measurement of platelet-mediated force development during clot retraction and of clot elastic modulus. We report 10 patients with immunoglobulin (Ig) G myeloma in whom the abnormalities of fibrin structure were quantitatively defined and platelet-fibrin interactions were assessed. Fiber mass-to-length ratios were calculated from gel turbidity. Platelet force development and clot elastic modula were measured in platelet-rich plasma gels. Fiber mass-to-length ratios for IgG myeloma patients were smaller (means +/- SE) (0.98 +/- 0.19 x 10(13) Da/cm) than for normal controls (1.36 +/- 0.06 x 10(13) Da/cm), indicating thinner fiber formation. Elastic modula of myeloma clots (51,013 +/- 14,660 dyn/cm2) were strikingly larger than modula for normal controls (23,355 +/- 1,887 dyn/cm2), indicating that such clots are mechanically less flexible. Platelet force development 1,200 s after thrombin addition was not diminished in myeloma patients (8,315 +/- 1,155 dyn) vs. controls (6,906 +/- 606 dyn). Abnormal clot retraction in myeloma appears to be primarily due to altered clot structure rather than platelet dysfunction.
authors.affiliation: Department of Medicine, Medical College of Virginia, Richmond.
authors.forename: M E
authors.initials: ME
authors.lastname: Carr
authors.forename: S L
authors.initials: SL
authors.lastname: Zekert
mesh_terms: D000368:Aged; D001777:Blood Coagulation / Q000187:drug effects; D001792:Blood Platelets / Q000502:physiology*; D003018:Clot Retraction; D004548:Elasticity; D004594:Electrophysiology; D005337:Fibrin / Q000737:chemistry*; D006801:Humans; D007074:Immunoglobulin G / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D009101:Multiple Myeloma / Q000097:blood*; D012016:Reference Values; D008258:Waldenstrom Macroglobulinemia / Q000097:blood
chemical_list: D007074:Immunoglobulin G; D005337:Fibrin