RT Book, Section
A1 Marshall, John
A2 Tintinalli, Judith E.
A2 Stapczynski, J. Stephan
A2 Ma, O. John
A2 Yealy, Donald M.
A2 Meckler, Garth D.
A2 Cline, David M.
SR Print(0)
ID 1121497967
T1 Sickle Cell Disease In Children
T2 Tintinalli’s Emergency Medicine: A Comprehensive Study Guide, 8e
YR 2016
FD 2016
PB McGraw-Hill Education
PP New York, NY
SN 9780071794763
LK accessmedicine.mhmedical.com/content.aspx?aid=1121497967
RD 2024/04/19
AB Sickle  cell  disease  is  a  spectrum  of  blood  disorders  of  which  sickle  cell  anemia  (SCA)  is  the  most  serious.  SCA  is  found  primarily  in  children  of  African,  Arab,  or  Mediterranean  descent.  It  is  caused  by  a  single  amino  acid  substitution  in  the  sixth  position  of  the  β-globulin  chain  of  normal  adult  hemoglobin  (HbA),  which  creates  the  abnormal  sickle  hemoglobin  (HbS).  The  HbS  chain  found  in  patients  with  SCA  creates  a  hydrophobic  region  of  the  hemoglobin  tetramer  when  it  is  deoxygenated.1  In  this  state,  noncovalent  polymerization  of  the  hemoglobin  molecules  creates  chains  that  distort  the  shape  of  the  membrane,  causing  the  characteristic  sickle  appearance.  The  altered  red  blood  cell  shape  and  its  associated  rigidity  and  decreased  deformability  cause  sickle  cells  to  impede  blood  flow.  This  is  responsible  for  most  of  the  clinical  manifestations  of  SCA  through  two  primary  mechanisms:  hemolytic  anemia  and  vaso-occlusion  with  subsequent  ischemia-reperfusion  injury.  Interruption  of  blood  flow  created  by  the  abnormal  cells  leads  to  poor  tissue  perfusion,  acidosis,  and  hypoxia,  which  cause  further  sickling.  The  need  to  reverse  these  conditions  is  central  to  the  management  of  SCA-related  complications.