This article is about the presence of spheroid red blood cells. For the hereditary cause of this disorder, see Hereditary spherocytosis.
Spherocytosis is the presence of spherocytes in the blood, i.e. erythrocytes (red blood cells) that are sphere-shaped rather than bi-concave disk shaped as normal. Spherocytes are found in all hemolytic anemias to some degree. Hereditary spherocytosis and autoimmune hemolytic anemia are characterized by having only spherocytes.[1]
Spherocytosis
Spherocytosis seen in a peripheral blood smear from a patient with hereditary spherocytosis
Spherocytes are found in immunologically-mediated hemolytic anemias and in hereditary spherocytosis, but the former would have a positive direct Coombs test and the latter would not. The misshapen but otherwise healthy red blood cells are mistaken by the spleen for old or damaged red blood cells and it thus constantly breaks them down, causing a cycle whereby the body destroys its own blood supply (auto-hemolysis). A complete blood count (CBC) may show increased reticulocytes, a sign of increased red blood cell production, and decreased hemoglobin and hematocrit. The term "non-hereditary spherocytosis" is occasionally used, albeit rarely.[2]
Spherocytosis most often refers to hereditary spherocytosis. This is caused by a molecular defect in one or more of the proteins of the red blood cell cytoskeleton, including spectrin, ankyrin, Band 3, or Protein 4.2. Because the cell skeleton has a defect, the blood cell contracts to a sphere, which is its most surface tension efficient and least flexible configuration. Though the spherocytes have a smaller surface area through which oxygen and carbon dioxide can be exchanged, they in themselves perform adequately to maintain healthy oxygen supplies. However, they have a high osmotic fragility—when placed into water, they are more likely to burst than normal red blood cells. These cells are more prone to physical degradation.[citation needed]
In short, spherocytosis has an attribute of decreased cell deformability.[4]
Spherocytosis can be diagnosed in Peripheral blood film by seeing spherical red blood cells rather than biconcave. Because spherical red blood cells are more prone to lysis in water (because they lack some proteins in their cytoskeleton) there will be increased osmotic fragility on acidified glycerol lysis test.[citation needed]
Treatmentedit
Treatment may vary depending on the cause of the condition. In the case of hereditary spherocytosis, although research is ongoing, at this point there is no cure for the genetic defect that causes hereditary spherocytosis.[5] Current management focuses on interventions that limit the severity of the disease. Treatment options for this type of spherocytosis include:
Splenectomy: As in non-hereditary spherocytosis, acute symptoms of anemia and hyperbilirubinemia indicate treatment with blood transfusions or exchanges and chronic symptoms of anemia and an enlarged spleen indicate dietary supplementation of folic acid and splenectomy,[6] the surgical removal of the spleen. Splenectomy is indicated for moderate to severe cases, but not mild cases.[7] To decrease the risk of sepsis, post-splenectomy spherocytosis patients require immunization against the influenza virus, encapsulated bacteria such as Streptococcus pneumoniae and meningococcus, and prophylactic antibiotic treatment. However, the use of prophylactic antibiotics, such as penicillin, remains controversial.[5]
Partial splenectomy: Since the spleen is important for protecting against encapsulated organisms, sepsis caused by encapsulated organisms is a possible complication of splenectomy.[7] The option of partial splenectomy may be considered in the interest of preserving immune function. Research on outcomes is currently limited,[7] but favorable.[8]
^Robert S. Hillman; Kenneth A. Ault; Henry M. Rinder (2005). Hematology in clinical practice: a guide to diagnosis and management. McGraw-Hill Professional. pp. 146–. ISBN978-0-07-144035-6. Retrieved 15 November 2010.
^Thoma J, Kutter D, Casel S, et al. (2005). "HbSC hemoglobinopathy suspected by chest x-ray and red blood cell morphology". Acta Clin Belg. 60 (6): 377–82. doi:10.1179/acb.2005.057. PMID 16502600. S2CID 43340793.
^Hirschmann, editors, Douglas C. Tkachuk, Jan V. (2007). Wintrobe's atlas of clinical hematology. Philadelphia, PA [etc.]: Lippincott Williams & Wilkins. ISBN978-0781770231. {{cite book}}: |first1= has generic name (help)CS1 maint: multiple names: authors list (link)
^Mohandas, Narla; Gallagher, Patrick G. (2008-11-15). "Red cell membrane: past, present, and future". Blood. 112 (10): 3939–3948. doi:10.1182/blood-2008-07-161166. ISSN 0006-4971. PMC2582001. PMID 18988878.
^ abcAnthony S. Fauci; Eugene Braunwald; Dennis L. Kasper; Stephen L. Hauser; Dan L. Longo; J. Larry Jameson; Joseph Loscalzo (2008). Harrison's principles of internal medicine (17th ed.). New York: McGraw-Hill Medical. pp. Chapter 106. ISBN978-0071466332.[permanent dead link]
^Bolton-Maggs PH, Stevens RF, Dodd NJ, Lamont G, Tittensor P, King MJ (August 2004). "Guidelines for the diagnosis and management of hereditary spherocytosis". Br. J. Haematol. 126 (4): 455–74. doi:10.1111/j.1365-2141.2004.05052.x. PMID 15287938. S2CID 5870305.
^ abcBolton-Maggs, P. H. B.; Stevens, R. F.; Dodd, N. J.; Lamont, G.; Tittensor, P.; King, M. -J.; General Haematology Task Force of the British Committee for Standards in Haematology (2004). "Guidelines for the diagnosis and management of hereditary spherocytosis". British Journal of Haematology. 126 (4): 455–474. doi:10.1111/j.1365-2141.2004.05052.x. PMID 15287938. S2CID 5870305.
^Buesing, K. L.; Tracy, E. T.; Kiernan, C.; Pastor, A. C.; Cassidy, L. D.; Scott, J. P.; Ware, R. E.; Davidoff, A. M.; Rescorla, F. J.; Langer, J. C.; Rice, H. E.; Oldham, K. T. (2011). "Partial splenectomy for hereditary spherocytosis: A multi-institutional review". Journal of Pediatric Surgery. 46 (1): 178–183. doi:10.1016/j.jpedsurg.2010.09.090. PMID 21238662.
External linksedit
A picture of spherocytes from Medline
Hereditary Spherocytosis from Medscape
January 01, 1970
spherocytosis, this, article, about, presence, spheroid, blood, cells, hereditary, cause, this, disorder, hereditary, spherocytosis, presence, spherocytes, blood, erythrocytes, blood, cells, that, sphere, shaped, rather, than, concave, disk, shaped, normal, sp. This article is about the presence of spheroid red blood cells For the hereditary cause of this disorder see Hereditary spherocytosis Spherocytosis is the presence of spherocytes in the blood i e erythrocytes red blood cells that are sphere shaped rather than bi concave disk shaped as normal Spherocytes are found in all hemolytic anemias to some degree Hereditary spherocytosis and autoimmune hemolytic anemia are characterized by having only spherocytes 1 SpherocytosisSpherocytosis seen in a peripheral blood smear from a patient with hereditary spherocytosisSpecialtyHematology Contents 1 Causes 2 Pathophysiology 3 Diagnosis 4 Treatment 5 See also 6 References 7 External linksCauses editSpherocytes are found in immunologically mediated hemolytic anemias and in hereditary spherocytosis but the former would have a positive direct Coombs test and the latter would not The misshapen but otherwise healthy red blood cells are mistaken by the spleen for old or damaged red blood cells and it thus constantly breaks them down causing a cycle whereby the body destroys its own blood supply auto hemolysis A complete blood count CBC may show increased reticulocytes a sign of increased red blood cell production and decreased hemoglobin and hematocrit The term non hereditary spherocytosis is occasionally used albeit rarely 2 Lists of causes 3 Warm autoimmune hemolytic anemia Cold autoimmune hemolytic anemia paroxysmal cold hemoglobinuria Acute and delayed hemolytic transfusion reactions ABO hemolytic diseases of newborn Rh hemolytic disease of newborn Hereditary spherocytosis Intravenous water infusion or drowning fresh water Hypophosphatemia Bartonellosis Snake bites Hyposplenism Rh null phenotypePathophysiology editSpherocytosis most often refers to hereditary spherocytosis This is caused by a molecular defect in one or more of the proteins of the red blood cell cytoskeleton including spectrin ankyrin Band 3 or Protein 4 2 Because the cell skeleton has a defect the blood cell contracts to a sphere which is its most surface tension efficient and least flexible configuration Though the spherocytes have a smaller surface area through which oxygen and carbon dioxide can be exchanged they in themselves perform adequately to maintain healthy oxygen supplies However they have a high osmotic fragility when placed into water they are more likely to burst than normal red blood cells These cells are more prone to physical degradation citation needed In short spherocytosis has an attribute of decreased cell deformability 4 Diagnosis edit nbsp Spherocyte compared to other forms of poikilocytosis Spherocytosis can be diagnosed in Peripheral blood film by seeing spherical red blood cells rather than biconcave Because spherical red blood cells are more prone to lysis in water because they lack some proteins in their cytoskeleton there will be increased osmotic fragility on acidified glycerol lysis test citation needed Treatment editTreatment may vary depending on the cause of the condition In the case of hereditary spherocytosis although research is ongoing at this point there is no cure for the genetic defect that causes hereditary spherocytosis 5 Current management focuses on interventions that limit the severity of the disease Treatment options for this type of spherocytosis include Splenectomy As in non hereditary spherocytosis acute symptoms of anemia and hyperbilirubinemia indicate treatment with blood transfusions or exchanges and chronic symptoms of anemia and an enlarged spleen indicate dietary supplementation of folic acid and splenectomy 6 the surgical removal of the spleen Splenectomy is indicated for moderate to severe cases but not mild cases 7 To decrease the risk of sepsis post splenectomy spherocytosis patients require immunization against the influenza virus encapsulated bacteria such as Streptococcus pneumoniae and meningococcus and prophylactic antibiotic treatment However the use of prophylactic antibiotics such as penicillin remains controversial 5 Partial splenectomy Since the spleen is important for protecting against encapsulated organisms sepsis caused by encapsulated organisms is a possible complication of splenectomy 7 The option of partial splenectomy may be considered in the interest of preserving immune function Research on outcomes is currently limited 7 but favorable 8 Surgical removal of the gallbladder may be necessary 5 See also editAnemia Blood Blood diseases Red blood cells Hereditary diseasesReferences edit Robert S Hillman Kenneth A Ault Henry M Rinder 2005 Hematology in clinical practice a guide to diagnosis and management McGraw Hill Professional pp 146 ISBN 978 0 07 144035 6 Retrieved 15 November 2010 Thoma J Kutter D Casel S et al 2005 HbSC hemoglobinopathy suspected by chest x ray and red blood cell morphology Acta Clin Belg 60 6 377 82 doi 10 1179 acb 2005 057 PMID 16502600 S2CID 43340793 Hirschmann editors Douglas C Tkachuk Jan V 2007 Wintrobe s atlas of clinical hematology Philadelphia PA etc Lippincott Williams amp Wilkins ISBN 978 0781770231 a href Template Cite book html title Template Cite book cite book a first1 has generic name help CS1 maint multiple names authors list link Mohandas Narla Gallagher Patrick G 2008 11 15 Red cell membrane past present and future Blood 112 10 3939 3948 doi 10 1182 blood 2008 07 161166 ISSN 0006 4971 PMC 2582001 PMID 18988878 a b c Anthony S Fauci Eugene Braunwald Dennis L Kasper Stephen L Hauser Dan L Longo J Larry Jameson Joseph Loscalzo 2008 Harrison s principles of internal medicine 17th ed New York McGraw Hill Medical pp Chapter 106 ISBN 978 0071466332 permanent dead link Bolton Maggs PH Stevens RF Dodd NJ Lamont G Tittensor P King MJ August 2004 Guidelines for the diagnosis and management of hereditary spherocytosis Br J Haematol 126 4 455 74 doi 10 1111 j 1365 2141 2004 05052 x PMID 15287938 S2CID 5870305 a b c Bolton Maggs P H B Stevens R F Dodd N J Lamont G Tittensor P King M J General Haematology Task Force of the British Committee for Standards in Haematology 2004 Guidelines for the diagnosis and management of hereditary spherocytosis British Journal of Haematology 126 4 455 474 doi 10 1111 j 1365 2141 2004 05052 x PMID 15287938 S2CID 5870305 Buesing K L Tracy E T Kiernan C Pastor A C Cassidy L D Scott J P Ware R E Davidoff A M Rescorla F J Langer J C Rice H E Oldham K T 2011 Partial splenectomy for hereditary spherocytosis A multi institutional review Journal of Pediatric Surgery 46 1 178 183 doi 10 1016 j jpedsurg 2010 09 090 PMID 21238662 External links editA picture of spherocytes from Medline Hereditary Spherocytosis from Medscape Retrieved from https en wikipedia org w index php title Spherocytosis amp oldid 1194908073, wikipedia, wiki, book, books, library,
