Akademik

Hemoglobinuria
The presence of free hemoglobin in the urine, an abnormal finding, that may make the urine look dark. Hemoglobin is the protein in the red blood cells which carries oxygen from the lungs to the tissues of the body and returns carbon dioxide from the tissues to the lungs. The iron contained in hemoglobin gives red blood cells their characteristic color. Red blood cells are normally taken out of circulation after approximately 4 months; they are trapped and disassembled in the spleen, bone marrow, and liver. If, however, red cells hemolyze (break down) within the vascular system, the components are set free in the blood stream. Free hemoglobin is bound by haptoglobin (another protein) and reprocessed. But if the level of hemoglobin in the blood rises above the ability of haptoglobin to reclaim it, hemoglobin begins to appear in the urine — there is hemoglobinuria. Normally, there is no hemoglobin in the urine. Hemoglobinuria is a sign of a number of conditions including: {{}}acute nephritis (acute glomerulonephritis), burns, kidney cancer, malaria, paroxysmal nocturnal hemoglobinuria (dark urine in the morning that lightens up during the day), the hemolytic-uremic syndrome (HUS), pyelonephritis, sickle cell anemia (or any other type of hemolytic anemia), a transfusion reaction (due to an immune response against transfused red blood cells), thrombotic thrombocytic purpura (TTP), and tuberculosis of the urinary tract.
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The presence of hemoglobin in the urine, including certain closely related pigments that are formed from slight alteration of the hemoglobin molecule; when present in sufficient quantities, they result in the urine being colored varying shades from light red-yellow to fairly dark red. [hemoglobin + G. ouron, urine]
- epidemic h. the presence of hemoglobin, or of pigments derived from it, in the urine of young infants, attended with cyanosis, jaundice, and other conditions; may be due to secondary methemoglobinemia; also called Winckel disease.
- intermittent h. recurrent episodic attacks of h. characteristic of paroxysmal nocturnal h. or paroxysmal cold h..
- malarial h. a condition, now uncommon, resulting from Plasmodium falciparum infection (malignant tertian malaria with severe hemolysis); seen in whites after interrupted treatment. SYN: blackwater fever, hemoglobinuric fever, West African fever.
- march h. a form occurring after marathon races, protracted marching, or heavy physical exercise.
- paroxysmal cold h. a rare disorder in which acute severe hemolysis follows exposure to cold.
- paroxysmal nocturnal h. an infrequent disorder with insidious onset (usually in the third or fourth decade) and chronic course, characterized by episodes of hemolytic anemia, h. (chiefly at night), pallor, icterus or bronzing of the skin, a moderate degree of splenomegaly, and sometimes hepatomegaly; red blood cells are usually macrocytic and vary considerably in size, but there is no evidence of spherocytosis, erythrophagocytosis, or abnormal leukocytes. The disorder is a result of an abnormality of the red cell membrane which makes the red cell unusually sensitive to lysis by complement. SYN: Marchiafava-Micheli anemia, Marchiafava-Micheli syndrome.
- postparturient h. a sudden, severe hemolytic disease that appears sporadically in well-nourished dairy cows 2–4 weeks after calving, and usually occurs in stabled animals in the winter and early spring; the cause is not known, although the disease is often associated with hypophosphatemia. SYN: puerperal hemoglobinemia.
- toxic h. h. occurring after the ingestion of various poisons, in certain blood diseases, and in certain infections.

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he·mo·glo·bin·uria or chiefly Brit hae·mo·glo·bin·uria .hē-mə-.glō-bə-'n(y)u̇r-ē-ə n the presence of free hemoglobin in the urine
he·mo·glo·bin·uric or chiefly Brit hae·mo·glo·bin·uric -'n(y)u̇(ə)r-ik adj

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he·mo·glo·bin·uria (he″mo-glo″bĭ-nuґre-ə) the presence of free hemoglobin in the urine. hemoglobinuric adj

Medical dictionary. 2011.