RT Book, Section
A1 Prchal, Josef T.
A2 Kaushansky, Kenneth
A2 Lichtman, Marshall A.
A2 Prchal, Josef T.
A2 Levi, Marcel M.
A2 Press, Oliver W.
A2 Burns, Linda J.
A2 Caligiuri, Michael
SR Print(0)
ID 1121095073
T1 Primary and Secondary Erythrocytoses
T2 Williams Hematology, 9e
YR 2015
FD 2015
PB McGraw-Hill Education
PP New York, NY
SN 9780071833004
LK hemonc.mhmedical.com/content.aspx?aid=1121095073
RD 2024/04/19
AB SUMMARYIncreased  blood  red  cell  mass  can  be  termed  either  polycythemia  or  erythrocytosis;  no  clear  consensus  for  either  term  has  been  achieved.  Primary  polycythemias  are  caused  by  acquired  or  inherited  mutations  causing  functional  changes  within  hematopoietic  stem  cells  or  erythroid  progenitors  leading  to  an  accumulation  of  red  cells.  The  most  common  primary  polycythemia,  polycythemia  rubra  vera,  which  is  a  clonal  disorder,  is  discussed  in  Chap.  84;  other  primary  polycythemias,  such  as  those  inherited  from  mutations  in  the  erythropoietin  receptor  or  congenital  disorders  of  hypoxia  sensing,  are  discussed  herein.  In  contrast,  secondary  polycythemias  are  a  result  of  either  an  appropriate  or  inappropriate  increase  in  the  red  cell  mass,  most  often  as  a  result  of  augmented  levels  of  erythropoietin;  these  polycythemias  can  also  be  either  acquired  or  hereditary.  Although  the  clinical  presentations  of  primary  and  secondary  polycythemias  may  be  similar,  distinguishing  amongst  them  is  important  for  accurate  diagnoses  and  proper  management.For  example,  those  secondary  polycythemic  states  that  represent  an  appropriate  physiologic  compensation  to  tissue  hypoxia,  should  not  be  treated  by  phlebotomies.  An  occasional  patient  may  experience  hyperviscosity  symptoms  and  may  benefit  from  isovolemic  reduction  of  hematocrit.  Inappropriate  polycythemias  are  caused  by  erythropoietin-secreting  tumors,  self-administration  of  erythropoiesis-stimulating  agents,  including  androgens,  inherited  disorders  of  hypoxia  sensing,  or,  rarely,  some  endocrine  disorders  (described  in  Chap.  38).  Correction  of  hypoxia,  discontinuation  of  erythropoiesis-stimulating  agents  or  resection  of  erythropoietin-secreting  tumors  will  typically  correct  the  associated  polycythemia.