Postgraduate Medicine
ISSN: 0032-5481 (Print) 1941-9260 (Online) Journal homepage: http://www.tandfonline.com/loi/ipgm20
Autoimmune hemolytic anemia 3. Cold antibody type Charles A. Horwitz To cite this article: Charles A. Horwitz (1979) Autoimmune hemolytic anemia 3. Cold antibody type, Postgraduate Medicine, 66:4, 189-200, DOI: 10.1080/00325481.1979.11715281 To link to this article: http://dx.doi.org/10.1080/00325481.1979.11715281
Published online: 07 Jul 2016.
Submit your article to this journal
View related articles
Citing articles: 2 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ipgm20 Download by: [Australian Catholic University]
Date: 02 September 2017, At: 06:34
LABORATORY MEDICINE A Series
Downloaded by [Australian Catholic University] at 06:34 02 September 2017
Autoimmune hemolytic anemia 3. Cold antibody type To conclude this three-part presentation on the autoimmune hemolytic anemias, this article looks at the cold type, considering the various cold agglutinins, methods of detecting them in the la bora tory, and the clinical disorders they may produce. The warm type of autoimmune hemolytic anemia was discussed in the August issue (page 167) and the drug-induced type in September (page 199).
Charles A. Horwitz, MD
The term "cold autoimmune hemolytic anemia" (AIHA) refers to a group of primary or secondary hemolytic conditions in which the causative autoantibodies are maximally reactive at low temperatures (0 to 10 C). 1-" These autoantibodies, or cold agglutinins, are mainly mac· roglobulins (lgM) that react in saline without the addition of protein adjuvants, such as albumin or the antihuman globulin reagent, or both. Most are able to activate and fix complement on the surface of human RBCs. For practical detection of cold agglutinins, serum is serially diluted in saline, 1.0% to 2.0% suspensions of group 0 Rh-negative erythrocytes are added to each test vial, and agglutination end points are read 60 to 120 minutes later following brief centrifugation. The titer is expressed as the reciprocal of the last dilution showing macroagglutination. Usually, titers > 1:64 are considered significant. A hemagglutination scoring system ( 1+ to 4+) can also be used to evaluate the strength of expression of cold agglutinins. By definition, cold aggluti-
nins show significant titer decline, or disagglutination, when RBC suspensions are rewarmed toward 37 C.
Ii blood-group system ln 1956, Weiner and associates" screened samples from 22,000 blood donors against serum from a patient with cold-type AIHA. Of the 22,000
One of a series of articles on orderlng and lnterpretlng laboratory tests whlch began ln Apr111978
VOL 66/NO 4/0CTOBER 1979/POSTGRADUATE MEDICINE
donor sam pies, 21,995 reacted with the serum and five were nonreactive for the unknown antibody. Weiner called the antibody anti-1; the erythrocytes in the samples that failed to agglutinate the serum he termed !-negative or adult i cells. ln subsequent studies, newborns were shown to Jack 1 on cord blood cells and thus were considered to have i-type erythrocytes. During infancy, the content of i decreases and of 1 increases; by 18 months of age, the switch from i to 1 is complete. Thus, most older children and adults have !-type erythrocytes. There is considerable individual variation in the strength of expression of the li system. 1 is thought to be a mosaic with both 1° (developed) and JF (fetal) components. 1° refers to a well-developed antigen of adult 1 RBCs that evolves from cord blood cell i, while JF refers to the residual 1 antigen of cord or adult ii cells. Anti-1° and -JF can be differentiated by their reactivity with reference cell samples of known li strength. 1 The strength of the li system varies with the underlying disease state, ie, patients who have carcinoma or are undergoing significant bone marrow stress may have a transient decrease in 1 and a relative continued
189
LABORATORY IIBDICINB CONTINUED
Downloaded by [Australian Catholic University] at 06:34 02 September 2017
The two most common cold agglutinins are designated anti·l and anti-i.
increase in i. As the patient improves, 1 returns to original strength. The rare adult i cells can be subdivided into two types, i, and i2 • Thus, the li system is considerably more complex than originally envisioned. 4 Types of cold agglutinins Anti-1 cold agglutinins are maximally reactive against adult RBCs. They are found ( 1) as pathologie autoantibodies in cold hemagglutination disease and other illnesses, (2) as harmless low-titer autoantibodies in almost ali normal persons, and (3) as alloantibodies in those rare adults with i erythrocytes. Anti-i cold agglutinins are maximally reactive against cord RBCs. They are found ( 1) in many patients with heterophil-positive or -negative infectious mononucleosis induced by Epstein-Barr virus (EBV),' (2) in a small percentage of patients with other lymphoproliferative disorders, and (3) occasionally ( < 1.0%) in other control groups. 6 Other cold agglutinin specificities include anti-MN, -Le•, -P~o -Pr, -H, and -Hl. Whereas titers of cold agglutinins of the li system are enhanced by erythrocyte premodification treatment with enzymes, antiPr cold agglutinin activity is de-
Charles A. Horwitz Dr Horwitz is associate pathologist, Mount Sinai Hospital, and associate professer of laboratory medicine and pathology, University of Minnesota Medical School, Minneapolis.
190
detect complement as weil as gamma globulin coating substances on the surface of RBCs. When monospecific reagents are used in the various cold AIHAs, complement-but not lgM-is usually identified. As noted earlier, the coating substance in most early cases of warm AIHA is lgG rather than complement.~
Table 1. Significance of cold agglutinine Cause of primary cold hemagglutination disease Usually high-titer anti-1, less commonly anti-Pr(Sp) and others Supportive laboratory data for various disease states Anti-i in infectious mononucleosis Anti-1 in Mycoplasma pneumoniae infection Anti-P (Donath-Landsteiner antibody) in paroxysmal cold hemoglobinuria Potential interference in routine cross-match procedure of hospital blood banks Clinically significant: eg, anti-1. -i. -A,. -P Usually insignificant: eg. low-titer autoanti-1. anti-HI. -M. -N. -Le8 • -Pr Potential cause of peripheral vascular obstruction on exposure to cold Acrocyanosis (Raynaud's phenomenon)
stroyed or significantly reduced with flein, bromelin, or trypsin treatment. 7 The majority of cold agglutinins belong to the 1 blood-group system. Their potential clinical significance is summarized in table 1. Direct antihuman globulin test (DAT) in cold AIHA The majority of cold agglutinins fix complement in vivo at reduced body temperatures. When body temperature returns to normal or a DAT is done at 25 C, lgM cold agglutinins often fall from the surface of RBCs while complement components remain fixed. Thus, it is important that antiglobulin serum be able to
Cold hemagglutination disease Cold hemagglutination disease is an uncommon chronic hemolytic anemia characterized by ( 1) high titers of cold agglutinins and (2) acrocyanosis, or Raynaud's phenomenon, due to cold-induced autoagglutination in peripheral vessels. It occurs mainly in elderly women. The usual characteristics of chronic hemolytic anemia, eg, persistent reticulocytosis, decrease in serum haptoglobin levels, and hemosiderinuria, are present. Bone marrow aspirate often reveals a significantly increased number of lymphocytes. The number of lymphoid cells increases with the duration of illness, so that marrow lymphocytosis of 60% to 90% may be seen with disease of 15 to 20 years' duration.~-" The po1yspecific DAT is a1ways positive in co1d hemagg1utination disease, and monospecific reagents usually demonstrate only complement on the sensitized erythrocytes. ln most cases, the cold agglutinins are specifie for anti-1; however, there is often sorne activity against cord b1ood cells (anti-JF). The cold
VOL 66/NO 4/0CTOBER 1979/POSTGRADUATE MEDICINE
Downloaded by [Australian Catholic University] at 06:34 02 September 2017
Anti·l agglutinins are found as pathologie auto· antibodies in cold hemagglutination disease and other illnesses, whereas anti·i agglutinins are found in many patients with EBV-induced infectious mononucleosis.
agglutinins are usually high-titered cluding prewarmed compatibility (> 1:1 ,000), with a thermal aggluti- testing, autoabsorption of cold autonin range up to 32 to 40 C. They are antibodies, and differentiai titraunique in that they usually demon- tian, are used to select proper donor strate kappa-type monoclonicity, in blood for patients with cold hemagcontrast to the polyclonal cold ag- glutination disease. When blood is glutinins seen after viral_ or other administered to such patients, it infectious disease. Patients with must be given through an in-line cold hemagglutination disease have blood warmer. a significant increase in lgM that is Case history-An 89-year-old due almost entirely to the cold ag- woman was hospitalized in 1969 for glutinins (ie, the bulk of the lgM in- evaluation of anemia (hemoglobin crement can be absorbed out [at 4 8.6 gmjdl), easy fatigability, and C] with adult 1 erythrocytes). 12 weakness (table 2). Mild anemia Therapy includes avoiding expo- (hemoglobin 11.2 to 12.8 gmjdl) sure to cold temperatures. This is had been present for severa) years, usually effective in relieving cutane- but there was no history of acrocyaous symptoms related to acrocyano- nosis, purpura, or arthritis. Physical sis. Steroids, penicillamine, and examination failed to disclose signifsplenectomy are usually of limited icant organomegaly. Blood smears value, while chlorambucil and cyclo- revealed prominent autoagglutinaphosphamide occasionally are help- tion of RBCs, scattered spherocytes, ful in particular problem cases. marked anisocytosis, prominent polyWhen blood transfusion is re- chromasia, and scattered nucleatquired in cold hemagglutination dis- ed RBCs (figure 1). The WBC ease, infusion of incompatible cells count was 8,900/cu mm and inis inevitable, since ali normal RBCs cluded 42% lymphocytes, 12% monocarry sorne 1 antigen. Blood transfu- cytes, 41% segmented neutrophils, sion is seldom helpful in such cases, and 5% eosinophils. The platelet because the transfused cells survive count was 385,000/cu mm, and the no longer than the patient's own reticulocyte count varied from 8.0% cells. However, unlike in warm to 13.4%. Cold agglutinins were AIHA, transfusion of incompatible significantly elevated (> 1:1 ,792), blood does not seem to further in- and serum haptoglobins were not crease the number of autoantibodies detected (
ISSN: 0032-5481 (Print) 1941-9260 (Online) Journal homepage: http://www.tandfonline.com/loi/ipgm20
Autoimmune hemolytic anemia 3. Cold antibody type Charles A. Horwitz To cite this article: Charles A. Horwitz (1979) Autoimmune hemolytic anemia 3. Cold antibody type, Postgraduate Medicine, 66:4, 189-200, DOI: 10.1080/00325481.1979.11715281 To link to this article: http://dx.doi.org/10.1080/00325481.1979.11715281
Published online: 07 Jul 2016.
Submit your article to this journal
View related articles
Citing articles: 2 View citing articles
Full Terms & Conditions of access and use can be found at http://www.tandfonline.com/action/journalInformation?journalCode=ipgm20 Download by: [Australian Catholic University]
Date: 02 September 2017, At: 06:34
LABORATORY MEDICINE A Series
Downloaded by [Australian Catholic University] at 06:34 02 September 2017
Autoimmune hemolytic anemia 3. Cold antibody type To conclude this three-part presentation on the autoimmune hemolytic anemias, this article looks at the cold type, considering the various cold agglutinins, methods of detecting them in the la bora tory, and the clinical disorders they may produce. The warm type of autoimmune hemolytic anemia was discussed in the August issue (page 167) and the drug-induced type in September (page 199).
Charles A. Horwitz, MD
The term "cold autoimmune hemolytic anemia" (AIHA) refers to a group of primary or secondary hemolytic conditions in which the causative autoantibodies are maximally reactive at low temperatures (0 to 10 C). 1-" These autoantibodies, or cold agglutinins, are mainly mac· roglobulins (lgM) that react in saline without the addition of protein adjuvants, such as albumin or the antihuman globulin reagent, or both. Most are able to activate and fix complement on the surface of human RBCs. For practical detection of cold agglutinins, serum is serially diluted in saline, 1.0% to 2.0% suspensions of group 0 Rh-negative erythrocytes are added to each test vial, and agglutination end points are read 60 to 120 minutes later following brief centrifugation. The titer is expressed as the reciprocal of the last dilution showing macroagglutination. Usually, titers > 1:64 are considered significant. A hemagglutination scoring system ( 1+ to 4+) can also be used to evaluate the strength of expression of cold agglutinins. By definition, cold aggluti-
nins show significant titer decline, or disagglutination, when RBC suspensions are rewarmed toward 37 C.
Ii blood-group system ln 1956, Weiner and associates" screened samples from 22,000 blood donors against serum from a patient with cold-type AIHA. Of the 22,000
One of a series of articles on orderlng and lnterpretlng laboratory tests whlch began ln Apr111978
VOL 66/NO 4/0CTOBER 1979/POSTGRADUATE MEDICINE
donor sam pies, 21,995 reacted with the serum and five were nonreactive for the unknown antibody. Weiner called the antibody anti-1; the erythrocytes in the samples that failed to agglutinate the serum he termed !-negative or adult i cells. ln subsequent studies, newborns were shown to Jack 1 on cord blood cells and thus were considered to have i-type erythrocytes. During infancy, the content of i decreases and of 1 increases; by 18 months of age, the switch from i to 1 is complete. Thus, most older children and adults have !-type erythrocytes. There is considerable individual variation in the strength of expression of the li system. 1 is thought to be a mosaic with both 1° (developed) and JF (fetal) components. 1° refers to a well-developed antigen of adult 1 RBCs that evolves from cord blood cell i, while JF refers to the residual 1 antigen of cord or adult ii cells. Anti-1° and -JF can be differentiated by their reactivity with reference cell samples of known li strength. 1 The strength of the li system varies with the underlying disease state, ie, patients who have carcinoma or are undergoing significant bone marrow stress may have a transient decrease in 1 and a relative continued
189
LABORATORY IIBDICINB CONTINUED
Downloaded by [Australian Catholic University] at 06:34 02 September 2017
The two most common cold agglutinins are designated anti·l and anti-i.
increase in i. As the patient improves, 1 returns to original strength. The rare adult i cells can be subdivided into two types, i, and i2 • Thus, the li system is considerably more complex than originally envisioned. 4 Types of cold agglutinins Anti-1 cold agglutinins are maximally reactive against adult RBCs. They are found ( 1) as pathologie autoantibodies in cold hemagglutination disease and other illnesses, (2) as harmless low-titer autoantibodies in almost ali normal persons, and (3) as alloantibodies in those rare adults with i erythrocytes. Anti-i cold agglutinins are maximally reactive against cord RBCs. They are found ( 1) in many patients with heterophil-positive or -negative infectious mononucleosis induced by Epstein-Barr virus (EBV),' (2) in a small percentage of patients with other lymphoproliferative disorders, and (3) occasionally ( < 1.0%) in other control groups. 6 Other cold agglutinin specificities include anti-MN, -Le•, -P~o -Pr, -H, and -Hl. Whereas titers of cold agglutinins of the li system are enhanced by erythrocyte premodification treatment with enzymes, antiPr cold agglutinin activity is de-
Charles A. Horwitz Dr Horwitz is associate pathologist, Mount Sinai Hospital, and associate professer of laboratory medicine and pathology, University of Minnesota Medical School, Minneapolis.
190
detect complement as weil as gamma globulin coating substances on the surface of RBCs. When monospecific reagents are used in the various cold AIHAs, complement-but not lgM-is usually identified. As noted earlier, the coating substance in most early cases of warm AIHA is lgG rather than complement.~
Table 1. Significance of cold agglutinine Cause of primary cold hemagglutination disease Usually high-titer anti-1, less commonly anti-Pr(Sp) and others Supportive laboratory data for various disease states Anti-i in infectious mononucleosis Anti-1 in Mycoplasma pneumoniae infection Anti-P (Donath-Landsteiner antibody) in paroxysmal cold hemoglobinuria Potential interference in routine cross-match procedure of hospital blood banks Clinically significant: eg, anti-1. -i. -A,. -P Usually insignificant: eg. low-titer autoanti-1. anti-HI. -M. -N. -Le8 • -Pr Potential cause of peripheral vascular obstruction on exposure to cold Acrocyanosis (Raynaud's phenomenon)
stroyed or significantly reduced with flein, bromelin, or trypsin treatment. 7 The majority of cold agglutinins belong to the 1 blood-group system. Their potential clinical significance is summarized in table 1. Direct antihuman globulin test (DAT) in cold AIHA The majority of cold agglutinins fix complement in vivo at reduced body temperatures. When body temperature returns to normal or a DAT is done at 25 C, lgM cold agglutinins often fall from the surface of RBCs while complement components remain fixed. Thus, it is important that antiglobulin serum be able to
Cold hemagglutination disease Cold hemagglutination disease is an uncommon chronic hemolytic anemia characterized by ( 1) high titers of cold agglutinins and (2) acrocyanosis, or Raynaud's phenomenon, due to cold-induced autoagglutination in peripheral vessels. It occurs mainly in elderly women. The usual characteristics of chronic hemolytic anemia, eg, persistent reticulocytosis, decrease in serum haptoglobin levels, and hemosiderinuria, are present. Bone marrow aspirate often reveals a significantly increased number of lymphocytes. The number of lymphoid cells increases with the duration of illness, so that marrow lymphocytosis of 60% to 90% may be seen with disease of 15 to 20 years' duration.~-" The po1yspecific DAT is a1ways positive in co1d hemagg1utination disease, and monospecific reagents usually demonstrate only complement on the sensitized erythrocytes. ln most cases, the cold agglutinins are specifie for anti-1; however, there is often sorne activity against cord b1ood cells (anti-JF). The cold
VOL 66/NO 4/0CTOBER 1979/POSTGRADUATE MEDICINE
Downloaded by [Australian Catholic University] at 06:34 02 September 2017
Anti·l agglutinins are found as pathologie auto· antibodies in cold hemagglutination disease and other illnesses, whereas anti·i agglutinins are found in many patients with EBV-induced infectious mononucleosis.
agglutinins are usually high-titered cluding prewarmed compatibility (> 1:1 ,000), with a thermal aggluti- testing, autoabsorption of cold autonin range up to 32 to 40 C. They are antibodies, and differentiai titraunique in that they usually demon- tian, are used to select proper donor strate kappa-type monoclonicity, in blood for patients with cold hemagcontrast to the polyclonal cold ag- glutination disease. When blood is glutinins seen after viral_ or other administered to such patients, it infectious disease. Patients with must be given through an in-line cold hemagglutination disease have blood warmer. a significant increase in lgM that is Case history-An 89-year-old due almost entirely to the cold ag- woman was hospitalized in 1969 for glutinins (ie, the bulk of the lgM in- evaluation of anemia (hemoglobin crement can be absorbed out [at 4 8.6 gmjdl), easy fatigability, and C] with adult 1 erythrocytes). 12 weakness (table 2). Mild anemia Therapy includes avoiding expo- (hemoglobin 11.2 to 12.8 gmjdl) sure to cold temperatures. This is had been present for severa) years, usually effective in relieving cutane- but there was no history of acrocyaous symptoms related to acrocyano- nosis, purpura, or arthritis. Physical sis. Steroids, penicillamine, and examination failed to disclose signifsplenectomy are usually of limited icant organomegaly. Blood smears value, while chlorambucil and cyclo- revealed prominent autoagglutinaphosphamide occasionally are help- tion of RBCs, scattered spherocytes, ful in particular problem cases. marked anisocytosis, prominent polyWhen blood transfusion is re- chromasia, and scattered nucleatquired in cold hemagglutination dis- ed RBCs (figure 1). The WBC ease, infusion of incompatible cells count was 8,900/cu mm and inis inevitable, since ali normal RBCs cluded 42% lymphocytes, 12% monocarry sorne 1 antigen. Blood transfu- cytes, 41% segmented neutrophils, sion is seldom helpful in such cases, and 5% eosinophils. The platelet because the transfused cells survive count was 385,000/cu mm, and the no longer than the patient's own reticulocyte count varied from 8.0% cells. However, unlike in warm to 13.4%. Cold agglutinins were AIHA, transfusion of incompatible significantly elevated (> 1:1 ,792), blood does not seem to further in- and serum haptoglobins were not crease the number of autoantibodies detected (
