Hemolytic Anemia Jean M. Connors, MD Brigham and Women’s Hospital Dana Farber Cancer Institute Harvard Medical School Boston, MA
Hemolytic Anemia
Jean M. Connors, MD
Brigham and Women’s Hospital
Dana Farber Cancer Institute
Harvard Medical School
Boston, MA
Conflicts of Interest
Pfizer/Bristol Meyer SquibbIndependent Review CommitteeScientific Ad BoardsConsultant
PortolaScientific Ad Boards
Unum TherapeuticsDSMB
• Overview of hemolytic anemia– Non-immune
• HS, HE• G6PD
– Immune• WAIHA• CAD
• Testing• Treatment
Outline
Question 2
• Anemia: How do you know it is hemolytic? – Increased reticulocyte count and absolute
retics– Peripheral smear: abnormal RBC
morphology– Decreased haptoglobin– Increased LDH– Increased indirect bilirubin– DAT: negative or positive?
• If positive what type of antibody
Approach
Question 2
• Classification– Intrinsic vs extrinsic to RBC– Non-immune– Autoimmune – Alloimmune
• Site of destruction– Intravascular vs extravascular
Approach
Question 2
• Inherited, with rare exceptions (PNH, acquired alpha thal)
• Mutations resulting in:– Membrane/cytoskeleton component defect– Hemoglobinopathy– Decreased enzymatic/metabolic function
Intrinsic RBC Etiology
Question 2
• Antibodies• Hypersplenism• Shear stress• Oxidants• Pathogens
– Malaria– Babesiosis– Clostridium perfringens
Extrinsic RBC Etiology
Question 1
• Most common inherited enzyme defect– Multiple mutations, track with ethnicity– can not reduce NADP or subsequently glutathione
• X-linked– males more significantly affected
• Most patients asymptomatic• Hemolytic crises linked to oxidative stress:
– Infection– Drugs– Fava beans: Mediterranean variant only
– Chemicals– Diabetic ketoacidosis
G6PD Deficiency
Glucose-6-Phosphate (G6PD) Deficiency
Figure 10-7 Heinz bodies in a patient withoxidant hemolysis.
Bunn & Lux, Chapter 10
Figure 10-6 Red cell metabolic pathways.
Question 1
• Diagnosis– Heinz bodies (denatured, pptd hgb), bite cells on smear– G6PD enzyme activity level
• Not accurate during acute crisis– Beutler fluorescent spot test– PCR for common variants (Mediterranean, A-)
• Treatment– Avoid offending drugs, foods, chemicals– Transfuse if necessary– Folic acid– Splenectomy often ineffective
G6PD Deficiency
Question 1
• Drugs– Antimalarials
• Primaquin, quinacrine– Sulfonamides– Dapsone– Phenacetin, asa– Nitrofurans– Mothballs– Rasburicasewww.g6pd.org/en/G6PDDeficiency/SafeUnsafe
G6PD Deficiency
Question 1• Mutations in cytoskeletal proteins
– Ankyrin 50-60% HS and 90% HE– Spectrin, band 3 in HS, protein 4.1 in HE
• Clinical severity ranges from mild to severe– Evidence of hemolytic anemia from birth– Exacerbations of hemolysis only when stressed
• infection
• Diagnosis– Evidence of extravascular hemolysis– Peripheral smear– Osmotic fragility test: hypotonic NaCl solutions– EMA: decreased eosin-5-maleimide binding by RBCs
assessed by flow cytometry
HS and HE
Osmotic Fragility
-HS and HE RBCs rupture with only mild change from normal tonicity.-10-20% will have normal osmotic fragility
Hereditary Spherocytosis (HS) and Hereditary Elliptocytosis (HE)
Figure 10-4 Hereditary elliptocytosis
Figure 10-3 Blood film – hereditary spherocytosis
An & Mohandas, British Journal of Haematology, 141, 367–375Bunn & Lux, Chapter 10
HS and HE
“vertical”
“horizontal”
Question 1
• Treatment: varies with severity– “typical” HS and HE: mild to moderate anemia,
increased bili, splenomegaly, erythroid hyperplasia– Severe and atypical forms rare, manifest from birth,
can have life threatening hemolytic crises • Splenectomy
– Normalizes RBC lifespan, anemia and increased biliusually resolve, spherocytes persist
– Treat with folate especially if hemolysis persists• Gallstones
– Pigmented stones common
HS and HE
Question 1
• Autoimmune
• Alloimmune– Transfusion– HSCT– Maternal/fetal: Rh, Kell
• Drug induced
Immune Hemolytic Anemia
Question 1
• Warm autoimmune hemolytic anemia (WAIHA)
• Cold agglutinin syndrome (CAS)
• Paroxsymal cold hemoglobinuria (PCH)– Donath Landsteiner antibodies
• Mixed AIHA
• Atypical AIHA (DAT negative)
• The first RCT of any treatment for any AIHA was published this year—for warm AIHA
Autoimmune Hemolytic Anemia
Extravascular hemolysis
Jandl JH: Blood. Textbook of Hematology,2nd ed. Boston: Little, Brown, 1996
www.medicinenet.com
Direct Antiglobulin Test (DAT)
Zantek 2012, Am J Hem 87:707
+ -
AHG: anti-human globulinpolyspecific mix
Anti-IgGAnti-C3
Question 1• Incidence: 1 to 2 cases/100,000 per year• F > M• Adults > children• IgG pan-agglutinins, react with all cells
– Ag target usually protein, often Rh but poorly defined– Extravascular hemolysis
• Primary (idiopathic)• Secondary
– CLL– Lymphomas and lymphoproliferative disorders– SLE
WAIHA
WAIHA: diagnosis
www.pathologystudent.com
DAT:IgG +C3d +/-
Hgb Retic LDH Bilirubin Haptoglobin
WAIHA
WAIHA: therapyOften extremely rapid onset, patients have significant
symptoms: weakness, SOB, tachycardiaTransfuse, despite difficulty with cross match
• 1st line therapy: steroids– Prednisone 1 mg/kg/d– Continue at least 2 weeks until hct clearly improved,
then slow taper– 80% respond within 3 weeks– Less than 20% have sustained response– “Failure” usually defined as requiring more than 15
mg/day of prednisone or equivalent to maintain Hgb>10; Hct >30
Primary WAIHA: Treatment
WAIHA: therapy
• 2nd line therapy: refractory or relapsedSplenectomy:
– 80% early CR, 60-70% CR at 2-3 yrs– May reduce steroid requirement– Complications: sepsis, thrombosis– Laparoscopic vs open splenectomy
Primary WAIHA: Treatment
WAIHA: therapy• 3rd line therapy: rituximab• Standard 4-wk dosing• 80% initial response• Poor data on long term outcome, but likely fewer long
term responses than in ITP• Preferred therapy in those w/ contraindications to
splenectomy
• Refractory: – MMF, csa, cytoxan, vincristine, azathioprine,
alemtuzumab
Primary WAIHA: Treatment
WAIHA: therapy• Use rituximab as 1st line with steroids?
• Meta-analysis of rituximab in AIHA – Overall response rate 70% for warm AIH– Complete response rate 42% for warm AIHA
• RCT of rituximab* vs placebo in newly diagnosed warm AIHA, in conjunction with prednisone.– 1 yr ORR 75% rituximab vs 31% placebo (p=0.032)
– 2 yrs 10/16 still with CR vs 3/16 placebo– More infections in placebo group
Primary WAIHA: TreatmentRituximab—2nd Line?
Autoimmun Rev 2015
* Two doses of 1000 mg 2 weeks apart Am. J. Hematol. 2017
• Treat WAHIA alone or underlying disorder or both?
• SLE– Steroids alone usually successful– Splenectomy not as effective, rituximab :PML risk?
• CLL– Fludarabine associated WAIHA
• NHL– Poor response to steroids, splenectomy– Treatment aimed at lymphoma
Secondary WAIHA: Treatment
Secondary WAIHA: Treatment
Lechner K , and Jäger U Blood 2010;116:1831-1838
Patients with CLL have increased risk of infection due to disease associated immunosuppression, age, treatment co-morbidity.
Primary CAD: clinical features
• Symptoms and findings
– Chronic anemia
– Intravascular hemolysis
– Hemoglobinuria, urine hemosiderin
– Plasma hemoglobin
– Acrocyanosis
Cold Agglutinin Syndromes
• IgM antibodies against carbohydrate antigens– I vs I
• Primary cold agglutinin disease (CAD)– Incidence: 1/1,000,000 F=M– Monoclonal B cell lymphoproliferative disorder usually
with IgMk against I antigen
• Secondary cold antibody-mediated AIHA– Mycoplasma pneumoniae: anti-I IgM– Infectious mononucleosis: anti-i IgM– Lymphoid neoplasms: anti-I or anti-i IgM– SLE
Cold Agglutinin Syndromes
CAS: diagnosis
DAT:IgG -C3d +
Hgb Retic LDH Bilirubin
www.pathologystudent.com Cold agglutinin titer
Cold Agglutinin Syndromes: Diagnosis
Etiology and treatment of primary cold agglutinin disease
Ulrich Jaeger Blood 2017;130:392-393
©2017 by American Society of Hematology
Primary CAD: therapy• Cold avoidance
• Steroids and splenectomy generally not effective
• Plasmapheresis– Acute management
• Chemo and immunotherapies: Goal is often PR, transfusion independence, and not CR– Rituximab ORR 57%, CR 21% Autoimmun Rev 2015
Refractory to rituximab alone– Fludarabine plus rituximab—old– Rituximab plus bendamustine--new
Primary CAD: Therapy
Question 1
• Prospective multicenter study in 45 patients – 18 previously treated with R, R+flu, other
• 4 cycles– Rituximab 375 mg/m2 day 1– Bendamustine 90 mg/m2 day1,2
• Excellent response: overall 71% • 3 relapses in 32 responders with 32 months follow up
—Q 2Rituximab and Bendamustine in CAD
Berentsen, Blood July 2017
Question 1
• Eculizumab– Case reports – Phase II study in 13 patients: decreased hemolysis
and transfusion requirements ASH 2015
• TNT009– Inhibits C1s in the classical complement pathway– In vitro, mouse, and healthy volunteer studies
demonstrate inhibition of activation of classical complement pathway and formation of C3b
• Both require indefinite treatment or use as bridge until response from other treatments achieved
—Q 2Complement inhibition in CAD
DAT-negative WAIHA
DAT IgG molecules per RBC0 <25-120
½+ 1201+ 2002+ 300-500
3-4+ >500
Petz LD. Immune Hemolytic Anemias 2nd Ed. Philadelphia: Churchill Livingstone, 2004
DAT Negative WAHIA
Hemolytic Anemia: Unanswered questions
1-10% WAIHA cases will have negative Coombs.Reasons for a negative Coombs Test:
• Low titer antibody that is insufficient to agglutinate the cells in a Coombs Test
• Low affinity antibody that is removed with washing during the test
• Alternative isotype antibody that doesn’t react with Coombs sera –IgA: 1-2%
• Patient doesn’t have AIHA
DAT Negative WAHIA
• Enhanced DAT– Many enhanced antibody detection techniques:
• Flow cytometry, low ionic strength wash, polybrene– Detect low concentration of antibody– Detect alternative isotypes – Positive in 90% Coombs negative WAIHA– Negative test does not absolutely rule out WAIHA
– Must also consider alternative diagnosis
DAT Negative WAIHA
Autoimmune Hemolytic Anemia
• Vaccinate prior to splenectomy• Pneumococcus• Haemophilus influenza• Meningococcus• Influenza• Provide prophylactic antibiotics
• Open vs laproscopic?• Portal vein thrombosis rate estimated at 8-50%• No definitive answer for open vs laproscopic• VTE prophylaxis post-op?
• Increased risk over lifetime of thrombosis?• Increased PE, ischemic heart disease
Splenectomy
Jean M. Connors [email protected]