TY  - CHAP
M1  - Book, Section
TI  - Chapter 433. Hemolytic Anemia
A1  - Yates, Amber Mayfield
A1  - Ware, Russell E.
A2  - Rudolph, Colin D.
A2  - Rudolph, Abraham M.
A2  - Lister, George E.
A2  - First, Lewis R.
A2  - Gershon, Anne A.
PY  - 2011
T2  - Rudolph's Pediatrics, 22e
AB  - Red  blood  cells  (RBCs)  have  a  normal  life  span  of  approximately  120  days.  An  operational  definition  of  hemolysis,  therefore,  is  accelerated  RBC  destruction  with  premature  removal  from  the  circulation,  which  usually  causes  anemia.  Hemolytic  anemia  can  occur  in  a  wide  range  of  clinical  settings  featuring  various  etiologies;  signs  and  symptoms  reflect  the  location  and  severity  of  hemolysis.  Intravascular  hemolysis  occurs  when  erythrocytes  are  destroyed  in  the  blood  vessel  itself,  whereas  extravascular  hemolysis  occurs  in  the  hepatic  and  splenic  macrophages  within  the  reticuloendothelial  system.  Intravascular  hemolysis  is  often  dramatic,  with  free  hemoglobin  released  into  the  plasma  leading  to  hemoglobinuria  (positive  blood  on  urine  dipstick  but  few  erythrocytes  on  microscopic  examination).  Examples  of  intravascular  hemolysis  include  enzyme  defects  such  as  glucose-6-phosphate  dehydrogenase  (G6PD)  deficiency  or  certain  immune-mediated  processes.  Extravascular  hemolysis  usually  results  from  more  subtle  RBC  destruction,  typically  with  chronic  splenic  enlargement  and  jaundice.  Extravascular  hemolysis  is  more  common  with  RBC  membrane  disorders  such  as  hereditary  spherocytosis.  Some  forms  of  hemolytic  anemia  feature  both  intravascular  and  extravascular  hemolysis.  The  degree  of  anemia  depends  on  how  rapidly  the  erythrocytes  are  being  removed  from  circulation  and  how  well  the  bone  marrow  compensates  with  increased  reticulocytosis.  
SN  - 
PB  - The McGraw-Hill Companies
CY  - New York, NY
Y2  - 2024/04/19
UR  - accesspediatrics.mhmedical.com/content.aspx?aid=7039705
ER  -