This document discusses autoimmune hemolytic anemia (AIHA). It begins by defining hemolytic anemia and classifying it as either congenital/hereditary or acquired. It then discusses the classification of hemolytic anemias as either intracorpuscular or extracorpuscular. The mechanisms, clinical features, laboratory findings, and treatments of warm AIHA and cold AIHA are described in detail. Warm AIHA is mediated by IgG antibodies and most commonly involves the Rh blood group antigen. Cold AIHA involves IgM antibodies reactive below 37°C and usually targets the I antigen. Corticosteroids are first-line treatment for warm AIHA while cold AIHA may be associated with underlying infections or malignancies.

1. AUTO IMMUNE HEMOLYTIC
ANEMIA
CHAIR PERSON:DR SACHIN HOSKATTI
STUDENT: AKSHATHA K

2. HEMOLYTIC ANEMIA
Definition:
Those anemias which result from an increase in RBC
destruction coupled with increased erythropoiesis
Classification:
Congenital / Hereditary
Acquired

3. CLASSIFICATION OF HEMOLYTIC ANEMIAS
INTRACORPUSCULAR EXTRACORPUSCULAR
DEFECTS FACTORS
HEREDITARY •HEMOGLOBINOPATHIES
•ENZYMOPATHIES
•MEMBRANE-
CYTOSKELETAL DEFECTS
•FAMILIAL HEMOLYTIC
UREMIC SYNDROME
ACQUIRED •PAROXYSMAL •MECHANICAL DESTRUCTION
NOCTURNAL [MICROANGIOPATHIC]
HEMOGLOBINURIA •TOXIC AGENTS
•DRUGS
•INFECTIOUS
•AUTOIMMUNE

4. CLASSIFICATION
Intravascular hemolysis
MAHA
Transfusion rx
PNH
Infections
Snake bite
Extravascular hemolysis
Hemoglobinopathies
Enzymopathies
Membrane defects
AIHA

7. HOW TO DIAGNOSE HEMOLYTIC ANEMIA
New onset pallor or anemia
Jaundice
Splenomegaly
Gall stones
Dark colored urine
Leg ulcers

8. GENERAL FEATURES
OF HEMOLYTIC DISORDERS
GENERAL EXAMINATION - JAUNDICE, PALLOR
BOSSING OF SKULL
PHYSICAL FINDINGS
HEMOGLOBIN
MCV
RETICULOCYTES
BILIRUBIN
LDH
HAPTOGLOBULIN
- ENLARGED SPLEEN
- FROM NORMAL TO SEVERELY REDUCED
- USUALLY INCREASED
- INCREASED
- INCREASED[MOSTLY UNCONJUGATED]
- INCREASED
- REDUCED TO ABSENT

10. HEMOLYTIC FACIES- CHIPMUNK FACIES

11. Laboratory Evaluation of Hemolysis
Extravascular Intravascular
HEMATOLOGIC
Routine blood film
Reticulocyte count
Bone marrow
examination
PLASMA OR SERUM
Polychromatophilia
Erythroid
hyperplasia
Polychromatophilia
Erythroid
hyperplasia
Bilirubin Unconjugated Unconjugated
Haptoglobin , Absent Absent
Plasma hemoglobin N/
Lactate dehydrogenase (Variable) (Variable)
URINE
Bilirubin + +
Hemosiderin 0 +
Hemoglobin 0 + severe cases

12. CASE SCENARIO 1
 A young male patient who is a soldier presented
with complaints of passage of dark urine
immediately following physical exertion in the
upright position, occasionally accompanied by
nausea, abdominal cramps, aching in the back or
legs, a “stitch in the side,” or a burning feeling in the
soles of the feet .
 Physical examination is transient jaundice usually
unrevealing, hepatosplenomegaly and transient
jaundice have been rarely reported

13.  Post exercise, his urine sample was
reddish brown in color with a specific
gravity of 1.030,
pH 5.5,
1+ protein,
3+ blood,
0 to 2 RBC/high powered field (HPF)
and
0 to 2 white blood cells/HPF.
His urine microscopy revealed 1 to 2
RBC/ HPF.

14. MARCH HEMOGLOBINURIA
(INTRAVASCULAR HEMOLYSIS)

15. IMMUNE HEMOLYTIC ANEMIA:
 When erythrocytes are destroyed prematurely by
an immune mediated process (antibody and/or
complement), the disorder is referred to as an
immune hemolytic anemia(IHA).
 Autoimmune hemolytic anemia
 Drug-induced hemolytic anemia
 Alloimmune hemolytic anemia

16. AUTOIMMUNE DRUG INDUCED ALLOIMMUNE
Warm-reactive antibodies
Primary or idiopathic
Secondary
1. Autoimmune disorders (SLE,RA,
and others)
2. Chronic lymphocytic leukemia
and other immunoproliferative
diseases
3. Viral infections
4. Neoplastic disorders
5. Chronic inflammatory diseases
Cold-reactive antibodies
Primary or idiopathic (cold
hemagglutinin disease)
Secondary
1. Infectious diseases
(mycoplasma pneumoniae,
EBVand other organisms)
2. Lymphoproliferative disorders
3. Paroxysmal cold hemoglobinuria
Mixed - type
Drug adsorption
Immune complex
Autoantibody induction
Membrane modification
Hemolytic transfusion
reaction
Hemolytic disease of
the fetus and newborn

17. CLINCAL SCENARIO 2
 Zohra begum,40yrs,female
 Chief complaints: yellowing of skin,fatigue since 5
months,ulcer at back since 3 months
 On examination:pallor+,icterus +
 P/A examination splenomegaly +
 Other systemic examination normal
 I/V: Retic count :3.6%
LDH:1062U/L
DIRECT COOMB’S +
ANA +

18. AUTOIMMUNE HEMOLYTIC ANEMIA

19. AUTOIMMUNE HEMOLYTIC ANEMIA
 AIHA is a complex and incompletely understood process
characterized by an immune reaction against self-antigens
and shortened erythrocyte survival .
 Individuals produce antibodies against their own
erythrocyte antigens (autoantibodies).
 The autoantibodies characteristically react not only with
the erythrocytes of the individual but also with the
erythrocytes of other individuals carrying the antigen.

21. SITES AND FACTORS
THAT AFFECT HEMOLYSIS
 Hemolysis can be intravascular or extravascular
Erythrocytes sensitized with antibody
or complement components attach to
macrophages in the spleen or liver
via macrophage receptors for the Fc
portion of immunoglobulin
or the C3b component of
complement. These
cells are then phagocytized .
Intravascular hemolysis
occurs if the complement cascade is
activated through C9 (the membrane
attack complex).
INTRAVASCULAREXTRAVASCULAR

25. MECHANISM OF HEMOLYSIS
IgG- Mediated Hemolysis
Complement Mediated Hemolysis
IgM-Meddiated Hemolysis

26. IgG – Mediated
Hemolysis

27. IgG mediates erythrocyte destruction by first attaching to
the erythrocyte membrane antigens through the Fab portion
of the Ig molecule.
Fc receptors on macrophages in the red pulp of the
spleen bind to the Fc portion of the attached IgG
After binding, the macrophage pits the antigen antibody
(Ag/Ab) complex, fragmenting the cell membrane
spherocyte
RIGID
LESS DEFORMABALE
Phagocytosed by splenic macrophages

29. COMPLEMENT MEDIATED HEMOLYSIS

31. IGM MEDIATED HEMOLYSIS
 Macrophages doesn’t have receptors for
Fc portion IgM
 IgM is efficient activator of complement
EXTRAVASCULAR:
- complement activation incomlete
- C3b coats RBCs and sensitised cells
destroyed extravascularly via CR1 and
CR3 receptors on macrophages
 IgM can agglutinate cells in addition to activating
complement.

32. LABORATORY IDENTIFICATION
OF SENSITIZED RED CELLS
 When immune hemolytic anemia is suspected,
tests to detect and identify the causative antibody
are indicated. In general, two distinct techniques
are used:
• Agglutination in saline, which will detect antibodies
of the IgM class
• Antihuman globulin (AHG) test, which will
detect antibodies of the IgG class and/or
complement

33. ANTIHUMAN GLOBULIN TEST:
IgM antibodies can be detected by agglutination
reactions between test sera and appropriate
erythrocytes suspended in saline.
Erythrocytes Zeta potiential(25nm)
Direct: detects erythrocytes coated with antibody
in vivo
Indirect: detects antibodies in the plasma or serum

38. WARM AUTOIMMUNE
HEMOLYTIC ANEMIA
 Most common form of AIHA (70% of cases)
 Incidence-1/50,000 -75,000
 Mediated by IgG antibodies whose maximal reactivity is
at 37°C.
 • Primary or idiopathic: no underlying disease
 • Secondary: underlying disease present
• Lymphoproliferative disease
• Neoplastic diseases
• Autoimmune disoders
• Viral and bacterial infections
• Vaccinations

39. Diseases or Conditions Associated with Warm
Autoimmune Antibodies
Autoimmune disorders
Systemic lupus erythematosus
Rheumatoid arthritis
Scleroderma
Ulcerative colitis
Antiphospholipid antibodies
Lymphoproliferative disorders
Chronic lymphocytic leukemia
Acute myelocytic leukemia
Hodgkin lymphoma
Non-Hodgkin lymphoma
Waldenström macroglobulinemia
Other lymphoproliferative disorders
Multiple myeloma

40. Other neoplastic disorders
Thymoma
Ovarian dermoid cyst
Teratoma
Kaposi sarcoma
Carcinoma
Viral infections
Epstein-Barr virus
Hepatitis C virus
HIV/AIDS
Other
Diphtheria-pertussis-tetanus vaccinations
Pregnancy
Bone marrow transplantation
Congenital immune deficiency states
Hypogammaglobulinemia
Dysglobulinemia

41. ANTIBODY CHARACTERISTICS
 Immunochemistry and Origin
Most antibodies are IgG (IgG1>IgG3)
 Blood Group Specificity
Warm autoantibodies are panagglutinins
Rh is the most common (70%),
Other blood group include Wright (Wrb), Ena,
Duffy (Fyb), Gerbich (Ge), Kidd (Jka), Kell (K),
Lutheran (Lu), LW, M, N, S, Pr, A, B, IT, Sc3, U, Vel,
and Xga .

42. PATHOPHYSIOLOGY
 The warm autoantibody in AIHA is reactive with
antigens on the patient’s erythrocytes.
 Specificity of the antibody is directed against
antigens of the Rh system.
 Most hemolysis in WAIHA is extravascular via
splenic macrophages.
 If both antibody and complement are on the cell
membrane, phagocytosis is enhanced.
 Direct complement- mediated intravascular
hemolysis associated with IgM antibodies in warm
AIHA is rare.

44. CLINICAL FEATURES:
Idiopathic AIHA:
Progressive weakness,
Dizziness,
Dyspnea on exertion,
Back or abdominal pain,
Jaundice.
Secondary AIHA:
patient can present with signs and
symptoms of both the underlying disease and
hemolysis or just the disease.

47. Laboratory Findings Associated with
WAIHA
Common findings
Other laboratory findings
that can be associated
with hemolysis in WAIHA
Positive DAT
Normocytic, normochromic anemia
Increased reticulocytes
Spherocytes and other erythrocyte
abnormalities
Presence of autoantibody in the serum
Increased serum bilirubin (total and
unconjugated)
Decreased serum haptoglobin
Positive antibody screen with all cells
including autocontrol
Incompatible crossmatches with all donors
Increased osmotic fragility
Increased urine and fecal urobilinogen
Hemoglobinemia,* hemoglobinuria,
methemoglobinemia,
hemosiderinurea

49. THERAPY:
 CORTICOSTEROIDS:
 Glucocorticoids are the initial therapy of choice for
warm AIHA
 Dose:1.0 to 1.5 mg/kg or 40 mg/m2/day of
prednisone or its equivalent.
 Response: noticeable by 7 days.
 Tapering: Rapid responders can reduce their dose
by 50% over 4 to 6 weeks, tapering should proceed
more slowly over 3 to 4 months

50. SPLENECTOMY
 Splenectomy is indicated in those surgical
candidates who have not responded to prednisone,
 And who requires prednisone doses >10-20 mg/day
to maintain remission, or
 Intolerable side effects.

51. IMMUNOSUPPRESSIVE THERAPY
 Immunosuppressive regimen might include
• 80 mg/m2/day
• or
AZATHIOPRINE
• 60 mg/m2/day
• or
CYCLOPHOSP
HAMIDE
• 40 mg/m2/day
PREDNISONE

52.  Rituximab: is a chimeric human/murine
monoclonal anti-CD20 antibody
 Mycophenolate mofetil: Doses begin at 1
g/day and are then increased to 2 g/day.
 Cyclosporine A:
Doses of 3 mg/kg/day with target serum levels of
200–400 ng/ml
• 375 mg/m2/week
× 4 weeksRituximab

53.  Other Therapies
 Intravenous immunoglobulin (IVIG) has not enjoyed
the success in AIHA that it has in immune
thrombocytopenia.
 Escalating the dose from the standard 0.4 g/kg/day
(× 5 days) to 1.0 g/kg/day may be helpful.
 Plasmapheresis

54. COLD AUTOIMMUNE HEMOLYTIC
ANEMIA (AIHA)
 Cold AIHA, also termed cold agglutinin disease
(CAD), is associated with an IgM antibody that fixes
complement and is reactive below 37°C.
 This disorder, which comprises 16–30% of the
AIHAs
 IgA and IgG antibodies rarely have been implicated
in hemolysis in CAD

55. ANTIBODY CHARACTERISTICS
 Immunochemistry and Origin:
 Cold agglutinins are IgM.
 Specificity for the I antigen:
 I antigen-90%
 i antigen-10%
 Adult RBCs are used to detect anti-I agglutinins and
cord RBCs are needed to detect anti-i agglutinins.
 M. pneumoniae induces anti-I antibodies in the majority
of patients is potentially related to the finding that
sialylated I/i antigens serve as specific Mycoplasma
receptors

56. Secondary Cold Agglutinin Disease
Neoplasms
Waldenstrom macroglobulinemia
Angioimmunoblastic lymphoma
Other lymphomas
Chronic lymphocytic leukemia
Kaposi sarcoma
Myeloma
Nonhematologic malignancy (rare)
Infections
Mycoplasma pneumoniae
Mononucleosis (Epstein-Barr virus)
Adenovirus
Cytomegalovirus
Encephalitis
Influenza viruses
Rubella

57. Rubella
Varicella
Human immunodeficiency virus
Mumps
Ornithosis
Legionnaires disease
Escherichia coli
Subacute bacterial endocarditis
Listeriosis
Syphilis
Trypanosomiasis
Malaria
Other
Autoimmune diseases
Tropical eosinophilia

59. PATHOPHYSIOLOGY:
 The severity of CAD is related to the thermal range
of the antibody(up to 32%)
 I antigen specificity
 Cold-reacting antibody is usually directed against
the I antigen.
 The second most common specificity for cold
autogglutinins is anti-Pr.1.

62. CLINICAL FEATURES
 Mild, chronic hemolytic anemia with exacerbations in the
winter.
 and jaundice may occur if the rate of hemolysis is
greater than the endogenous capability to metabolize
bilirubin .
 Intermittent bursts of hemolysis associated with
hemoglobinemia and hemoglobinuria on exposure to
cold.
 Acrocyanosis can occur from agglutination of RBCs in
the cooler vessels of the hands, ears, nose, and feet.
 Digits may become cold, stiff, painful, or numb and may
turn purplish
 Chronic CAD patients have mild splenomegaly or
hepatomegaly

67. THERAPY
 The most effective therapy is usually achieved by
keeping the individual’s extremities warm.
 Chemotherapy using cyclophosphamide or
chlorambucil can be instituted(Underlying
lymphoproliferative disease)
 Plasma exchange.
 Rituximab has been used as treatment in both
primary and secondary disease.
Chlorambucil, beginning with 2 to 4 mg/day and increasing by
2 mg every 2 months
Pulse therapy with cyclophosphamide (250 mg/day) and
prednisone (100 mg/day × 4 days) every 2 to 3 weeks

68. CASE SCENARIO 3
 A four-year-old male presents to the emergency department
with a history of six days of fever and acute onset of red
colored urine. There has been no recent travel. He was seen
by his Doctor approximately five days ago for evaluation of
cough and rhinorrhea and was prescribed Antibiotics for an
ear infection.No h/o dysuria, bloody stools, hemoptysis, or
epistaxis. He has no increased bruising, no petechiae, and no
extremity pain. He has been having intermittent fevers for
three days.
 Physical Exam: (+) scleral icterus, (+) jaundice, (+) soft flow
murmur on cardiac exam. Physical exam is otherwise normal.

69. LABS:
 Initial hemoglobin 10.4 g/dL--> decreased to 6.3 g/dL 12
hours later,
 Platelets 153,000 cells/UL,
 Reticulocyte count 0.4%,
 White blood cells 11.1 x103cells
 Coagulation studies normal.
 Liver function test are normal.
 LDH is 5056 Units/ml,
 Haptoglobin 12 mg/dL (low).
 Unconjugated bilirubin is 3.7 mg/dL,
 Conjugated bilirubin is 1.2 mg/dL.
 Electrolytes are all within normal limits. Viral panel is pending.
 DAT: IgG, C3 (+).
 Urinalysis: dark, red-brown urine, 3+ blood, 3+ protein, 0-4
RBCs/hpf, 0-4 WBCs/hpf, urobilinogen >8mg/dL.

70. PAROXYSMAL COLD
HEMOGLOBINURIA
 Characterized by massive intermittent acute hemolysis
and hemoglobinuria.
 Can occur at any age ,frequently seen in children less
than 5 years.
 The infections linked to PCH include
Epstein-Barr virus,
Cytomegalovirus,
Measles, mumps,
Heamophilus influenzae,
Klebsiella pneumoniae.
Parvovirus 19,
Onset : 5 days to 3 weeks after onset of the infection

71. PATHOPHYSIOLOGY
 Donath-Landsteiner (D-L) antibody.
 Biphasic refers to the two temperatures necessary
for optimal lysis of the erythrocytes.
The antibody reacts with
erythrocytes in the
capillaries at temperatures
less than 20°C and avidly
binds the early acting
complement components.
The antibody molecule
disperses from the cell, but
the membrane attack
complement components
are activated on the cell
membrane causing cell
lysis.
TEMP <20°C TEMP @37°C

72. CLINICAL FINDINGS
 Hemoglobinuria
 Jaundice
 Pallor
 Hepatosplenomegaly
 Raynaud’s phenomenon

73. LAB INVESTIGATIONS
Neutropenia.
Reticulocytopenia.
Serum bilirubin, BUN, and LD are elevated
Serum complement and haptoglobin are
decreased.
DAT with anticomplement antisera :Weakly
positive.
IAT can be positive if performed in the cold
D-L antibodies :low titres(1:32)

76. THERAPY
 PCH associated with acute infections terminates
upon recovery from the infection.
 Steroids are not usually helpful.
 Transfusion can be required if the hemolysis is
severe.
 In rare cases when the hemolysis persists,
plasmapheresis can be used.
 Rituximab (anti-CD20) has also been used as
therapy

77. MIXED-TYPE AIHA
 Mixed-type AIHA is characterized by the presence
of a warmreacting IgG autoantibody and a cold-
reacting IgM autoantibody that has both high titer
and increased thermal amplitude.
 About 50% of the cases are idiopathic.
 Associated with diseases such as systemic lupus
erythematosus, lymphoma, and HIV.
 Patients usually respond well to treatment with
corticosteroids and do not require transfusion.
 Rituiximab has been used in cases with underlying
lymphoproliferative disease

78. DRUG-INDUCED HEMOLYTIC ANEMIAS
 It is recognized that certain drugs can cause
immune cytopenias that involve one or several cell
lines including neutrophils, platelets, and
erythrocytes.
 Three classic hypotheses
• Drug absorption
• Immune complex formation
• Autoantibody induction

85. CASE SCENARIO
 32 yr old presented 4 days history of distention
of
 abdomen and rt hypochondrial pain and has
h/o passage of dark colored urine at night for
weeks
 On USG- hepatomegaly,gross
ascites,hepatic vein thrombosis
 Lab : Hb – 7gm%. WBC- 2200, PLC- 80,000
 LDH- 600, S.BR- 4 mg%
 urine bile pigment +,heme dip stick++
 What is the diagnosis

86. CASE SCENARIO
 14 YR old female present with anemia, jaundice
 Rt hypochondrial pain
 o/e-vitals stable.pallor+,icterus+,splenomegaly +
 Usg- cholilithiasis
 Lab; elevated ,LDH, S.Bilirubin
 Peripheral smear shows

87. CASE SCENARIO
 25 yr old male with RHD – severe MR done
MVR,after 10
 days presented with pallor, palpitation,jaundice
 CBC shows Hb – 7.5 gm %, Hct -22 %
 Lab : S.bilirubin -4.5mg%
 LDH -600
 Retic count 10%
 Peripheral smear –

88. REFERENCES:
 Wintrobe’s Clinical Hematology
12th Edition
 Williams Hematology 9E
 Harrison’s principles of Internal Medicine
 Pearson New International Edition
Clinical Laboratory Hematology
Shirlyn B. McKenzie Second Edition

89. THANK YOU