Autoimmune hemolytic anemia: Definition from Answers.com

Autoimmune hemolytic anemia
Classification and external resources
ICD-10	D 59.0-D 59.1
ICD-9	283.0
MeSH	D000744

Autoimmune hemolytic anemia (AIHA) is a type of hemolytic anemia where the body's immune system attacks its own red blood cells (RBCs), leading to their destruction (hemolysis).^[1]^[2] Types of AIHA include Warm autoimmune hemolytic anemia, Cold agglutinin disease, and Paroxysmal cold hemoglobinuria.

1 Terminology
2 Pathophysiology
3 Classification
4 Laboratory findings
5 See also
6 References
7 External links

Terminology

Although MeSH uses the term "autoimmune hemolytic anemia",^[3] some sources prefer the term "immunohemolytic anemia" so that drug reactions can be included in this category.^[4]^[5]

The National Cancer Institute considers "immunohemolytic anemia", "autoimmune hemolytic anemia", and "immune complex hemolytic anemia" to all be synonyms.^[6]

Pathophysiology

Antibodies and associated complement system components become fixed onto the RBC surface. These antibodies can be detected with the direct antiglobulin test, also known as the direct Coombs test.

AIHA can also be induced by several drugs including methyldopa and fludarabine.

Classification

Haemolysis can be intravascular or extravascular.

Intravascular haemolysis: Red blood cell lysis occurs in the circulation as a result of activation of the complement system cascade.

Extravascular haemolysis: Red Blood Cells that are coated with antibodies are specifically recognized in the reticuloendothelial system and destroyed by macrophages.

Laboratory findings

Evidence for Haemolysis^[7]

Increased red cell breakdown:

Elevated serum bilirubin (unconjugated)
Excess urinary urobilinogen
Reduced plasma haptoglobin
Raised serum lactic dehydrogenase (LDH)

Increased red cell production:

Reticulocytosis
Erythroid hyperplasia of the bone marrow

Specific Investigations

Positive direct Coombs test

References

^ Autoimmune hemolytic anemia at Mount Sinai Hospital
^ "Hemolytic Anemia: Overview - eMedicine Hematology". http://emedicine.medscape.com/article/201066-overview. Retrieved 2009-02-07.
^ MeSH Autoimmune+hemolytic+anemia
^ Wright MS (1999). "Drug-induced hemolytic anemias: increasing complications to therapeutic interventions". Clin Lab Sci 12 (2): 115–8. PMID 10387489.
^ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease. St. Louis, Mo: Elsevier Saunders. pp. 636. ISBN 0-7216-0187-1.
^ "Definition of immunohemolytic anemia - NCI Dictionary of Cancer Terms". http://www.cancer.gov/templates/db_alpha.aspx?CdrID=523291. Retrieved 2009-02-07.
^ Kumar P, Clark M (2005), Clinical Medicine 6th Ed, Elsevier Saunders pg 437

External links

Case report of Autoimmune Hemolytic Anemia with typical laboratory findings. Clinical Cases and Images.

Pathology: hematology · hematologic diseases of RBCs and megakaryocytes / MEP (D50-69,74, 280-287)

↑

↓

Micro-: Iron deficiency anemia (Plummer-Vinson syndrome)

Macro-: Megaloblastic anemia (Pernicious anemia)

Hemolytic
(mostly Normo-)

Hereditary	enzymopathy: G6PD · glycolysis (PK, TI, HK) hemoglobinopathy: Thalassemia (alpha, beta, delta) · Sickle-cell disease/trait · HPFH membrane: Hereditary spherocytosis (Minkowski-Chauffard syndrome) · Hereditary elliptocytosis (Ovalocytosis) · Hereditary stomatocytosis

Acquired	Autoimmune (WAHA, CAD, PCH) membrane (PNH) MAHA · TM (HUS) Drug-induced autoimmune · Drug-induced nonautoimmune Hemolytic disease of the newborn

Aplastic
(mostly Normo-)

Hereditary: Fanconi anemia · Diamond-Blackfan anemia

Acquired: PRCA · Sideroblastic anemia · Myelophthisic

Blood tests

MCV (Normocytic, Microcytic, Macrocytic) · MCHC (Normochromic, Hypochromic)

Other

Methemoglobinemia · Sulfhemoglobinemia · Reticulocytopenia

Coagulation/
coagulopathy/
bleeding
diathesis

↑

Thrombocytosis	Essential thrombocytosis

Hypercoagulability	primary: Antithrombin III deficiency · Protein C deficiency/Activated protein C resistance/Protein S deficiency/Factor V Leiden · Hyperprothrombinemia acquired: DIC (Congenital afibrinogenemia, Purpura fulminans) · autoimmune (Antiphospholipid)

↓

myeloid navs: cells/physio, disease of RBCs+megakaryocytes/monocytes+granulocytes/neoplasia, symptoms+signs/eponymous
↑ means increased, ↓ means decreased

Immune disorders: hypersensitivity and autoimmune diseases

Type I/allergy/atopy
(IgE)

Foreign	Atopic dermatitis · Allergic urticaria · Hay fever · Allergic asthma · Anaphylaxis · Food allergy (Milk, Egg, Peanut, Tree nut, Seafood, Soy, Wheat), Penicillin allergy

Autoimmune	none

Type II/ADCC
(IgM, IgG)

Foreign

Pernicious anemia · Hemolytic disease of the newborn

Autoimmune

Cytotoxic	Autoimmune hemolytic anemia · Idiopathic thrombocytopenic purpura · Bullous pemphigoid · Pemphigus vulgaris · Rheumatic fever · Goodpasture's syndrome

"Type 5"/receptor	Graves' disease · Myasthenia gravis

Type III
(Immune complex)

Foreign	Henoch-Schönlein purpura · Hypersensitivity vasculitis · Reactive arthritis · Rheumatoid arthritis · Farmer's lung · Post-streptococcal glomerulonephritis · Serum sickness · Arthus reaction

Autoimmune	Systemic lupus erythematosus · Subacute bacterial endocarditis

Type IV/cell-mediated
(T-cells)

Foreign	Contact dermatitis · Mantoux test

Autoimmune	Diabetes mellitus type 1 · Hashimoto's thyroiditis · Guillain–Barré syndrome · Multiple sclerosis · Coeliac disease · Giant cell arteritis

GVHD	Transfusion-associated graft versus host disease

Unknown/
multiple

Foreign	Hypersensitivity pneumonitis (Allergic bronchopulmonary aspergillosis) · Transplant rejection · Latex allergy (I+IV)

Autoimmune	Sjögren's syndrome · Autoimmune hepatitis · Autoimmune polyendocrine syndrome (APS1, APS2) · Autoimmune adrenalitis

lymphocyte navs: cells/physio, immunodeficiency/immunoproliferative immunoglobulin/neoplasia, proc

This immunology article is a stub. You can help Wikipedia by expanding it.

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)

Donate to Wikimedia

	What are the symptoms of hemolytic anemia? Read answer...
	How do you treat hemolytic anemia in dogs? Read answer...
	Can a person with hemolytic anemia be a blood donor? Read answer...

	What foods should a dog with autoimmune hemolytic anemia be fed?
	In a case of cold autoimmune hemolytic anemia a patient's serum would most likely react 4 at immediate spin with what?
	Nursing intervention for hemolytic anemia?

		Sci-Tech Dictionary. McGraw-Hill Dictionary of Scientific and Technical Terms. Copyright © 2003, 1994, 1989, 1984, 1978, 1976, 1974 by McGraw-Hill Companies, Inc. All rights reserved. Read more
		Medical Dictionary. The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Read more
		Wikipedia. This article is licensed under the Creative Commons Attribution/Share-Alike License. It uses material from the Wikipedia article "Autoimmune hemolytic anemia". Read more

Autoimmune hemolytic anemia

Contents