Chapter 20: Hemolytic Anemia Resulting from a Chemical or Physical Agent

INTRODUCTION

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)

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.)