TY  - CHAP
M1  - Book, Section
TI  - Hereditary and Acquired Sideroblastic Anemias
A1  - Lichtman, Marshall A.
A1  - Kaushansky, Kenneth
A1  - Kipps, Thomas J.
A1  - Prchal, Josef T.
A1  - Levi, Marcel M.
PY  - 2011
T2  - Williams Manual of Hematology, 8e
AB  - Sideroblastic  anemias  may  be  acquired  or  hereditary  (see  Table  11–1)  and  are  characterized  by:—  Ringed  (pathologic)  sideroblasts  and  increased  storage  iron  in  the  marrow  are  the  hallmarks  of  this  group  of  disorders.—  Increased  red  cell  precursors  in  the  marrow  in  the  face  of  anemia  and  a  low  reticulocyte  count  (ineffective  erythropoiesis).  The  anemia  is  the  result  of  increased  apoptosis  of  late  erythroid  precursors.—  A  population  of  hypochromic  erythrocytes  in  the  blood  film  is  a  common  finding.All  normal  red  cell  precursors  have  siderosomes,  iron-containing  cytoplasmic  aggregates  in  the  cytoplasm,  a  normal  part  of  intraerythrocytic  iron  metabolism  and  hemoglobin  synthesis.  They  can  be  seen  by  transmission  electron  microscopy.  These  aggregates  are  often  below  the  resolution  of  the  light  microscope.  Thus,  in  Prussian  blue-stained  marrow  specimens,  about  20  to  50  percent  of  normal  red  cell  precursors  can  be  found  to  have  one  to  three  very  small,  pinhead  sized  blue  granules  in  the  cytoplasm  under  oil  immersion  optics,  depending  on  the  quality  of  the  preparation.Pathologic  sideroblasts  are  of  two  types.  The  classical  type  is  a  ringed  sideroblast  with  relatively  large,  Prussian  blue-stained  granules  in  an  approximate  circumferential  position  around  the  nucleus  of  the  erythroblast.  This  location  reflects  their  intramitochondrial  location;  mitochondria  in  erythroblasts  being  positioned  closely  surrounding  the  nucleus.  The  other  type  of  pathologic  sideroblast  has  large  and  multiple  cytoplasmic  granules  (see  Fig.  11–1).Drugs  that  reduce  the  formation  of  pyridoxal  5′-phosphate  from  pyridoxine  decrease  heme  synthesis  and  cause  sideroblastic  anemia.The  main  factor  responsible  for  the  anemia  is  ineffective  erythropoiesis,  with  increased  plasma  iron  turnover,  normal  to  decreased  red  cell  survival,  and  increased  excretion  of  fecal  stercobilin.  
SN  - 
PB  - McGraw-Hill Education
CY  - New York, NY
Y2  - 2024/04/19
UR  - hemonc.mhmedical.com/content.aspx?aid=1126651243
ER  -