title: Extramedullary haematopoiesis in massive hepatic necrosis.
abstract: OBJECTIVE
  To determine the frequency of extramedullary haematopoiesis (EMH) in massive hepatic necrosis (MHN).
  
  
  RESULTS
  Explanted livers of 11 adult patients transplanted consecutively for MHN were examined histologically and immunohistochemically for the presence of EMH. The aetiology of the liver damage was unknown in seven cases and drug induced in four. The presence of stem cell markers (CD34, c-kit), erythroid precursors (glycophorin A), myeloid precursors (myeloperoxidase) and megakaryocyte precursors (CD31) was investigated by immunohistochemistry. Erythroid, myeloid and megakaryocyte precursors were observed in all cases. Morphologically, haematopoietic blast cells were clustered in areas of collapse, separating islands of regenerating ductules and scattered between ductules, in a similar distribution to immunohistochemically identified c-kit-positive putative stem cells. No CD34+ cells other than endothelial cells were seen. All 11 patients were anaemic at the time of transplantation.
  
  
  CONCLUSIONS
  EMH is a frequent finding in patients undergoing liver transplantation for MHN. This may be a consequence of the anaemia associated with this condition. Alternatively, the possibility that intrahepatic haematopoiesis is linked with hepatopoiesis is an additional, intriguing possibility that deserves further study.
authors.affiliation: Academic Department of Histopathology, Royal Free and University College Medical School, London, UK. ccraig@rfc.ucl.ac.uk
authors.forename: C E H
authors.initials: CE
authors.lastname: Craig
authors.forename: A
authors.initials: A
authors.lastname: Quaglia
authors.forename: A P
authors.initials: AP
authors.lastname: Dhillon
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers; D005260:Female; D006021:Glycophorins / Q000378:metabolism; D006411:Hematopoiesis, Extramedullary / Q000502:physiology*; D006801:Humans; D007150:Immunohistochemistry; D008099:Liver / Q000473:pathology; D008297:Male; D047508:Massive Hepatic Necrosis / Q000503:physiopathology*; D008875:Middle Aged; D009195:Peroxidase / Q000378:metabolism; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism
chemical_list: D015415:Biomarkers; D006021:Glycophorins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D009195:Peroxidase