Myelofibrosis and acute megakaryoblastic leukemia in a child: topographic relationship between fibroblasts and megakaryocytes with an alpha-granule defect.

Abstract

In a child with acute megakaryoblastic leukemia--severe thrombocytopenia and myelofibrosis, EM studies on bone marrow showed a strict topographic relationship between the presence of clusters of abnormal megakaryocytes and the increased number of fibroblasts and extracellular fibers. Megakaryocytes and platelets lacked alpha-granules while the plasma thromboglobulin level was three times the normal level. This suggested that the alpha-granular proteins were synthesized but not retained in alpha-granules. If this occurs, the increased marrow levels of platelet-derived growth factor and factor 4 would favor the proliferation of fibroblasts and the synthesis of collagen, and thereby promote myelofibrosis. After therapy-induced remission, the number of marrow megakaryocytes decreased, the alpha-granules were normally produced, the plasma beta-thromboglobulin level was normal and the myelofibrosis disappeared. These observations suggest that during acute megakaryoblastic leukemia, an acquired gray-platelet syndrome occurs and that the local excretion of alpha-granule proteins triggers the myelofibrosis.

• Authors: J Breton-Gorius, M Bizet, F Reyes, E Dupuy, C Mear, J P Vannier, P Tron
• Journal: Leukemia research (Leuk Res) Vol. 6 Issue 1 Pg. 97-110 ( 1982) ISSN: 0145-2126 [Print] England
• PMID: 6461801 (Publication Type: Case Reports, Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• beta-Thromboglobulin

Topics

• Blood Platelets (ultrastructure)
• Bone Marrow (pathology, ultrastructure)
• Child, Preschool
• Female
• Humans
• Megakaryocytes (ultrastructure)
• Microscopy, Electron
• Primary Myelofibrosis (blood, complications, pathology)
• Thrombocythemia, Essential (blood, complications, pathology)
• beta-Thromboglobulin (blood)