Normal red blood cells live for about 3 to 4 months. Intravascular hemolysis hemoglobin release in the blood haptoglobin levels drop as it tries to capture free hgb hemoglobinuria dark urine extravascular hemolysis buildup of hgb breakdown products conjugating systems of liver are overwhelmed excess unconjugated bilirubin leaks into blood unconjugated bilirubinemia. Nov 25, 2017 i have mentioned that hemoglobinhaptoglobin complex forms in the plasma, but this is not true. Extravascular hemolytic transfusion reaction wikem.
Intravascular hemolysis results in hemoglobinemia when the amount of hemoglobin released into plasma exceeds the hemoglobinbinding capacity of the plasmabinding protein haptoglobin, a protein normally present in concentrations of about 100 mgdl 1. Indirect bilirubin is a byproduct of hemoglobin catabolism and is increased in intravascular or extravascular hemolysis. If the damage is severe enough, immediate lysis occurs within the circulation intravascular hemolysis if the damage is less severe, the cell is destroyed within the monocytemacrophage system in the spleen, liver, bone marrow, and lymph nodes extravascular hemolysis iv. Intravenous administration of a hypotonic solution or plain distilled water will also destroy red blood. Extravascular hemolysis refers to hemolysis taking place in the liver, spleen, bone marrow, and lymph nodes. Jan 18, 2012 normal intravascular and extravascular hemolysis 001. Intravascular hemolysis article about intravascular. Disease bioinformatics research of extravascular haemolysis has been linked to hemolysis disorder, anemia, anemia, hemolytic, intravascular hemolysis, hemoglobinuria. Causes of hemolytic anemia due to extracorpuscular defects i. Intravascular hemolysis the rbcs are lysed within the blood vessel such as by mechanical damage of a heart valve, or because of complement fixation as in paroxysmal nocturnal hemoglobinuria. Common causes of acquired intravascular hemolysis in adults microangiopathic hemolytic anemia.
Jun 01, 2004 microangiopathic hemolytic anemia maha, or fragmentation hemolysis, is caused by a mechanical disruption of the red blood cell membrane in circulation, leading to intravascular hemolysis and the. Intravascular vs extravascular hemolysis depending on the etiology, hemolysis may occur within the blood stream itself intravascular or be caused by increased destruction by the reticuloendothelial system. Extravascular hemolysis and complement consumption in. Intravascular hemolysis results in hemoglobinemia, hemoglobinuria, methemalbuminemia, and hemosiderinuria whereas splenomegaly is indicative of extravascular hemolysis. The study of extravascular haemolysis has been mentioned in research publications which can be found using our bioinformatics tool below. Hemolysis is the destruction of red blood cells in the circulation way before their life span is over. Alloimune hemolysis hemolytic transfusion reaction caused by recognition of foreign antigens on transfused blood cells several types immediate intravascular hemolysis minutes due to preformed antibodies. Daven port transfusion medicine division, department of pathology, university of michigan, ann arbor, michigan. Somatic mutation occurs on the piga gene codes cd55 and cd59 this prevents rbcs from being protected from lysis via complement. Daven port transfusion medicine division, department of pathology, university of. When the rbcs are prematurely removed from the circulation and destroyed by the macrophages in the spleen and liver, it is referred to as extravascular hemolysis. Inc in expired carbon monoxide carboxyhemoglobin unconjugated bilirubin urine and fecal urobilinogen dec haptoglobin in severe hemolysis 15.
Extravascular hemolysis definition of extravascular. Intravascular hemolysis may occur when red blood cells are targeted by autoantibodies, leading to complement fixation, or by damage by parasites such as babesia. To identify the presentation, diagnosis, management of common hemolytic anemia such as spherocytosis, enzymopathies, autoimmune hemolysis and acquired non immune hemolytic anemia. Overview of hemolytic anemia hematology and oncology. To differentiate between intravascular and extra vascular hemolysis. Tsuji a1, tanabe m, onishi k, kitamura t, okinaka t, ito m, isaka n, nakano t. Intravascular hemolysis is the destruction of red blood cells occurring intravascularly, or within the circulation. Intravascular hemolysis is also suggested by urinary hemosiderin. Extracorpuscular hemolytic anemia linkedin slideshare. Rother, phd leonard bell, md peter hillmen, mb, phd mark t. Pleiotropic effects of intravascular hemolysis on vascular.
Dark urine and intra vs extravascular hemolysis student. In addition, intravascular hemolysis releases the erythrocyte contents directly into plasma, as distinguished from extravascular hemolysis, in which reticuloendothelial macrophages phagocytose senescent red cells, with little or no release of erythrocyte contents into plasma. Autoimmune hemolytic anemia hematology and oncology. Intravascular and extravascular hemolysis of infected rbcs may occur in malaria. Causes include mechanical trauma, complement fixation, and other toxic damage to the rbc. Intravascular hemolysis is suggested by rbc fragments schistocytes on the peripheral smear and by decreased serum haptoglobin levels. I have mentioned that hemoglobinhaptoglobin complex forms in the plasma, but this is not true. Hemolysis may be either intravascular or extravascular.
Symptoms of hemolytic anemia are similar to other anemias and include. The hemoglobin is released into the blood and immediately bound by haptoglobin for clearance in the liver. Some microbes form substances called hemolysins that have the specific action of destroying red blood cells. With extravascular hemolysis which is normally how effete rbc are removed from the circulation, i. Overview of hemolytic anemia hematology and oncology msd. The direct antiglobulin test dat, also known as the direct coombs test, demonstrates the presence of. On the other hand deficiency of pyruvate kinase leads to extravascular hemolysis by splenic macrophages. Drugs and toxins may cause intravascular hemolysis through the formation of heinz bodies resulting in damaged membranes thus destroying rbcs. Intravascular hemolysis and jaundice student doctor network. However, treatment responses are reported heterogeneous with some patients presenting residual hemolysis and requiring rbc transfusions. Pdf a case of extravascular hemolysis with tkactivation.
Intravascular hemolysis is the state when the red blood cell ruptures as a result of the complex of complement autoantibodies attached fixed on the surfaces of rbcs attack and rupture rbcs membranes, or a parasite such as babesia exits the cell that ruptures the rbcs membrane as it goes. Accelerated hemoglobin catabolism varies with the type of hemolysis as follows extravascular hemoglobin catabolism see figure 71. Intravascular hemolysis is the state when the red blood cell ruptures as a result of the complex of complement autoantibodies attached fixed on the surfaces of rbcs attack and rupture rbcs membranes, or a parasite such as babesia exits the cell that ruptures the rbcs membrane as it goes upon rbcs rupture, components of which are released and circulating. A 67yearold woman with rheumatic aortic stenosis for 20 years was admitted to our hospital. Depending on the etiology, hemolysis may occur within the blood stream itself intravascular or be caused by increased destruction by the reticuloendothelial system. Somatic mutation occurs on the piga gene codes cd55 and cd59 this prevents rbcs. Hemolysis is usually described as intravascular hemolysis or extravascular hemolysis. May 11, 2012 alloimune hemolysis hemolytic transfusion reaction caused by recognition of foreign antigens on transfused blood cells several types immediate intravascular hemolysis minutes due to preformed antibodies. Hemolytic anemia is a form of anemia due to hemolysis, the abnormal breakdown of red blood cells rbcs, either in the blood vessels intravascular hemolysis or elsewhere in the human body extravascular. Intravascular hemolysis and the pathophysiology of sickle cell disease article pdf available in journal of clinical investigation 1273. Hemolysis may occur in vivo or in vitro inside or outside the body one cause of hemolysis is the action of hemolysins, toxins that are produced by certain pathogenic. Learn vocabulary, terms, and more with flashcards, games, and other study tools.
Intravascular hemolysis is an important part of many anemias depending on its severity, hemolysis may contribute to vascular complications pulmonary hypertension, stroke, blood clots, leg ulcers, priapism screening strategies and treatments have been developed in scd. Extravascular hemolysis destruction of red cells by reticuloendothelial cells in the liver, spleen, and bone marrow significant lab finding. Ttp, hus, prosthetic valve leak direct trauma runners transfusion reactions infection clostridium perfringens sepsis with degradation of phospholipids of the red cell membrane bilayer and the structural membrane proteins, severe. This most commonly occurs within the spleen, but also can occur in the reticuloendothelial system or mechanically prosthetic valve damage. Examples include autoimmune hemolytic anemia, microangiopathic hemolytic anemias, disseminated intravascular coagulation.
There are numerous causes of hemolytic anemia, including inherited and acquired conditions, acute and chronic processes, and mild to potentially lifethreatening severity. Start studying intravascular and extravascular hemolysis. Hemolytic anemia ppt presentation linkedin slideshare. Intravascular versus extravascular hemolysis usmle forums. Transfusionassociated circulatory overload taco transfusionrelated acute lung injury trali. An understanding of this is important for physician assistant exam pance purposes.
In intravascular hemolysis rbcs lyse in the circulation releasing hemoglobin into the plasma. Gladwin, mdh emoglobin is a highly conserved molecule found in speciesrangingfromsinglecell organisms to mammals, but the role of hemoglobin in different organisms varies. Hemolytic anemia is defined as anemia due to a shortened survival of circulating red blood cells rbcs due to their premature destruction. Acquired hemolytic, megaloblastic and sideroblastic anemias. Pdf intravascular hemolysis and the pathophysiology of. Mar 10, 20 intravascular hemolysis the rbcs are lysed within the blood vessel such as by mechanical damage of a heart valve, or because of complement fixation as in paroxysmal nocturnal hemoglobinuria. Introduction acquired hemolytic anemias are a group of disorders characterized by hemolysis of red blood cells rbcs not due to congenital or inherited disorders of hemoglobin synthesis or of the rbc membrane. Hemolysis occurs in spleen, liver, and bone marrow.
Hemolysis of rbcs can take place within the intravascular space or in the extravascular spaces of the spleen and liver and. Acute intravascular hemolysis is due to destruction of erythrocytes by a sudden flux of copper ions from the necrosing hepatocytes. Autoimmune hemolytic anemia is caused by autoantibodies that react with red blood cells at temperatures. The destruction or dissolution of red blood cells, with subsequent release of hemoglobin. The clinical sequelae of intravascular hemolysis and.
A normocytic, normochromic anemia acute intravascular hemolysis is due to destruction of erythrocytes by a sudden flux of copper ions from the necrosing hepatocytes. The image above shows severe hemolysis red discolored supernatant plasma of blood centrifuged in a microhematocrit tube from edta plasma as part of a hemogram, where we assess plasma appearance in a dog with an immunemediated hemolytic anemia the dog has extravascular and intravascular hemolysis. Intravascular hemolysis represents a severe pathological condition in a number of vital organ systems. G6pd hemolysis is predominantly intravascular as hemolysis is due to increase oxidant stress inside rbc.
1265 1452 650 642 1605 1153 1229 49 1119 1364 328 1191 1509 114 1403 1071 1332 1076 701 1149 1075 1060 1507 816 272 77 329 815 423 739 662 1550 54 1507 542 350 509 1022 1281 43 673 552 788 967 652 1135