Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + INTRODUCTION Download Section PDF Listen +++ ++ Hemolysis can be mainly intravascular (ie, hypotonic lysis or heat damage) or predominantly extravascular (ie, arsine gas and oxygen). Certain drugs can induce hemolysis in individuals with abnormalities of erythrocytic enzymes, such as glucose-6-phosphate dehydrogenase, or with an unstable hemoglobin (see Chaps. 14 and 17). Such drugs can also cause hemolysis in normal individuals if given in sufficiently large doses. Other drugs induce hemolytic anemia through an immunologic mechanism (see Chap. 24). The drugs and chemicals discussed here cause hemolysis by other mechanisms. + ARSENIC HYDRIDE (ARSINE, AsH3) Download Section PDF Listen +++ ++ Arsine gas (arsenic hydride is formed in many industrial processes) may lead to hemolysis. In some areas, the water supply can be tainted with arsenic. Inhalation of arsine gas can lead to severe anemia, hemoglobinuria, and jaundice as a result of the oxidation of sulfhydryl groups in the red cell membrane. The red cells may become spherocytic and stomatocytic and severely hypochromic from hemoglobin loss (red cell ghosts) (Figure 20–1A). ++ FIGURE 20–1 A. Blood film prepared from a patient exposed to arsenic hydride (AsH). Note the very pale red cells resulting from partial hemoglobin loss secondary to membrane damage. An extreme example, represented by the virtual ghost thinly rimmed with scant residual hemoglobin, can be found in the upper left-hand corner. Other cells are spherocytic or stomatocytic. B. Blood film from person with lead poisoning. Note the tear-drop–shaped red cell with basophilic stippling. The stippling may be fine or course but may be minimized or absent in blood anticoagulated with Na2EDTA. C. Wilson disease. In this image from a patient with Wilson disease, there are numerous visible sequelae of oxidative damage caused by excess copper. The striking dense microspherocytes indicates damage to the membrane. Damage to hemoglobin is demonstrated by the Heinz bodies projecting from red cells (asterisks show two examples). The horizontal arrow points to one of several microspherocytes. The vertical arrow points to a macrocyte (reticulocyte). An occasional cell shows damage to both membrane and hemoglobin. The presence of echinocytes (oblique arrows show two examples) suggests that the liver is also affected. D. Blood film prepared at admission from a patient who had suffered severe burn injury involving a large percentage of the body surface. Note the presence of normal erythrocytes (apparently from vessels not exposed to heat damage) along with populations of normocytic and microcytic spherocytes. In addition, there are numerous red cell fragments, some smaller than platelets, from heat-related red cell fragmentation. (Images A, B, and D: Reproduced with permission from Lichtman’s Atlas of Hematology, www.accessmedicine.com; Image C: Used with permission from Barbara J. Bain, Imperial College, London, UK.) Graphic Jump LocationView Full Size||Download Slide (.ppt) + LEAD Download Section PDF Listen +++ ++ Lead poisoning in children usually is a result of ingestion of lead paint flakes or chewing lead-paint coated objects. In adults, it usually is the result of industrial exposure. Lead poisoning may lead to abdominal pain, confusion, headache, and in severe cases seizures, coma, and death. Lead intoxication leads to anemia largely caused by inhibition of heme synthesis and the rate of red cell production. There is also a modest decrease in red cell life span (mild hemolysis). Lead also inhibits pyrimidine 5′-nucleotidase (see Chap. 14), which may be responsible for the basophilic stippling of red cells found in lead poisoning. Basophilic stippling may be fine or coarse and is often found in polychromatophilic cells (see Figure 20–1B). The anemia is usually mild in adults but may be severe in children. Red cells are normocytic and slightly hypochromic. Ringed sideroblasts are frequently found in the marrow (see Chap. 11). + COPPER Download Section PDF Listen +++ ++ Hemolytic anemia may be induced by high levels of copper in patient’s hemodialyzed with fluid contaminated by copper tubing, or it may occur in patients with Wilson disease. Wilson disease may present or be called to medical attention by a hemolytic anemia, often having spherocytes and Heinz bodies as a result of copper injury to red cells (see Figure 20–1C). The presence of liver disease with a hemolytic anemia should raise the question of Wilson disease. (See Table 20–1 for laboratory findings in Wilson disease.) The hemolysis is probably caused by copper-induced inhibition of several erythrocyte enzymes and membrane injury. ++Table Graphic Jump LocationTABLE 20–1LABORATORY FINDINGS IN WILSON DISEASEView Table||Download (.pdf) TABLE 20–1 LABORATORY FINDINGS IN WILSON DISEASE Variable Normal Value Wilson Disease Serum ceruloplasmin (mg/L) 200–400 < 200 Serum copper (μM) 11–24 < 11 Urinary copper (μg/24 h) ≤ 40 > 100 Liver copper (μg/g dry weight) 20–50 > 200 + CHLORATES Download Section PDF Listen +++ ++ Ingestion of sodium or potassium chlorate, or contamination of dialysis fluid with chloramines, can cause oxidative damage with formation of Heinz bodies and methemoglobin and with development of hemolytic anemia. + MISCELLANEOUS DRUGS AND CHEMICALS Download Section PDF Listen +++ ++ Other drugs and chemicals that can cause hemolytic anemia are listed in Table 20–2. ++Table Graphic Jump LocationTABLE 20–2DRUGS AND CHEMICALS THAT HAVE BEEN REPORTED TO CAUSE HEMOLYTIC ANEMIAView Table||Download (.pdf) TABLE 20–2 DRUGS AND CHEMICALS THAT HAVE BEEN REPORTED TO CAUSE HEMOLYTIC ANEMIA Chemicals Drugs Aniline Amyl nitrite Apiol Mephenesin Dichlorprop (herbicide) Methylene blue Formaldehyde Omeprazole Hydroxylamines Pentachlorophenol Lysol Phenazopyridine (Pyridium) Mineral spirits Salicylazosulfapyridine (Azulfidine) Nitrobenzene Tacrolimus Resorcin Source: Williams Hematology, 9th ed, Chap. 52, Table 52–1. + WATER Download Section PDF Listen +++ ++ Water administered intravenously, inhaled in near-drowning, or gaining access to the circulation during irrigation procedures can cause hemolysis. + OXYGEN Download Section PDF Listen +++ ++ Hemolytic anemia has developed in patients receiving hyperbaric oxygenation and in astronauts exposed to 100% oxygen. + INSECT AND ARACHNID VENOMS Download Section PDF Listen +++ ++ Severe hemolysis may occur in some patients following bites by bees, wasps, spiders, or scorpions. Snake bites are only rarely a cause of hemolysis. + HEAT Download Section PDF Listen +++ ++ Patients with extensive burns may develop severe hemolytic anemia, apparently as a result of direct damage to the red cells passing through the skin and subcutaneous tissues by extreme heat. Blood films of many burned patients show spherocytes and fragmentation as a result of severe membrane injury. (See Figure 20–1D.) + NEOCYTOLYSIS Download Section PDF Listen +++ ++ Neocytolysis, the selective destruction of young red cells, is a phenomenon unique to microgravity and is associated with a rapid decrease in erythropoietin levels. It is experienced by astronauts after space flight, even in the presence of normal ambient oxygen concentration, or in people rapidly descending from high altitude to sea level. Radiolabeling studies of erythrocytes indicated that the anemia was caused by selective hemolysis of young erythrocytes less than 12 days old. ++ For a more detailed discussion, see Paul C. Herrmann: Hemolytic Anemia Resulting from Chemical and Physical Agents, Chap. 52 in Williams Hematology, 9th ed.
For a more detailed discussion, see Paul C. Herrmann: Hemolytic Anemia Resulting from Chemical and Physical Agents, Chap. 52 in Williams Hematology, 9th ed.