paroxysmal nocturnal hemoglobinuria

hemoglobinuria /he·mo·glo·bin·uria/ (he″mo-glo″bĭ-nu´re-ah) free hemoglobin in the urine.hemoglobinu´ric

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march hemoglobinuria  that seen after prolonged exercise.

paroxysmal cold hemoglobinuria  an autoimmune or postviral disease marked by episodes of hemoglobinemia and hemoglobinuria after exposure to cold, caused by complement-dependent hemolysis due to Donath-Landsteiner antibody.

paroxysmal nocturnal hemoglobinuria  (PNH) a chronic acquired blood cell abnormality with episodes of intravascular hemolysis and venous thrombosis.

toxic hemoglobinuria  that caused by ingestion of a poison.

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paroxysmal nocturnal hemoglobinuria

n.

An infrequent disorder the onset of which usually occurs in the third or fourth decades of life and is characterized by periods of hemolytic anemia, hemoglobinuria primarily at night, pallor, bronzing of the skin, moderate splenomegaly, and red blood cells that are macrocytic and vary considerably in size. Also called Marchiafava-Micheli syndrome.

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Paroxysmal nocturnal hemoglobinuria (PNH)

A rare complement disorder characterized by episodes of red blood cell destruction (hemolysis) and blood in the urine (hemoglobinuria) that is worse at night.

Mentioned in: Complement Deficiencies

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paroxysmal nocturnal hemoglobinuria (PNH),

a disorder characterized by intravascular hemolysis and hemoglobinuria. It occurs in irregular episodes of several days' duration, especially at night. The basic defect in the red blood cell is an unusual sensitivity to lysis by complement or a deficiency or absence of acetylcholinesterase. The cause of the condition is unknown, but it is seen in association with abnormalities of the function of the bone marrow. Occurring predominantly in adults between 25 and 45 years of age, it is characterized by abdominal pain, back pain, dark colored urine, and headache. Its course may be complicated by thrombotic episodes and by iron deficiency caused by excessive loss of hemoglobin. Therapy includes blood transfusion and the oral or parenteral administration of iron. Corticosteroids are sometimes used and found useful. Treatment of thromboses may require anticoagulant therapy.

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hemoglobinuria [he″mo-glo″bĭ-nu´re-ah]

the presence of free hemoglobin in the urine. adj., adj hemoglobinu´ric.

march hemoglobinuria hemolysis caused by repeated uncushioned shocks or trauma to some body part, such as in some soldiers on long marches, in marathon runners, and in karate practitioners.

paroxysmal cold hemoglobinuria an autoimmune or postviral disease in which there is a biphasic IgG antibody directed against the P blood group antigen. It is marked by episodes of hemoglobinemia and hemoglobinuria after exposure to cold and is detected by the Donath-Landsteiner test. The condition is treated with prednisone and cyclophosphamide and by protection from exposure to cold.

paroxysmal nocturnal hemoglobinuria (PNH) an acquired blood cell abnormality with proliferation of abnormal red blood cells (PNH cells) that are readily hemolyzed by complement, and episodes of severe hemolysis and thrombosis, particularly of the hepatic veins. It is detected by the ham test. Treatment is with androgens or prednisone and, during thrombotic episodes, with heparin.

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paroxysmal nocturnal hemoglobinuria

An acquired hemolytic disease, due to proliferation of an abnormal clone(s) of myeloid stem cells, the progeny of which are susceptible to complement-mediated membrane damage and hemolysis–CMH Clinical Thromboses, ↑ infections; PNH may evolve into aplastic or sideroblastic anemia, myelofibrosis, AML Lab Leukopenia, thrombocytopenia, dimorphic RBC population, iron-deficiency, ↓ leukocyte alk phos, ↓ RBC acetylcholinesterase, altered properdin–alternate pathway of complement lysis, hemoglobinuria, hemosiderinuria, positive Ham test, positive sucrose lysis test; negative direct Coombs' test, ↑ susceptibility of RBCs to CMH