recent advances and updates on anemia

1. APLASTIC ANEMIA
Ajay Kumar Yadav
PGY3,Medicine
IOM-TUTH, Kathmandu
2075/05/13

2. LAYOUT
• Historical background
• How to diff. acquired Vs constitutional AA
• Etiology
• Clinical features
• Diagnosis
• Management
• Bone Marrow Transplantation(BMT)
• Immune Suppressive Therapy(IST)

3. HISTORICAL BACKGROUND
• The earliest case description of aplastic anemia was by Dr. Paul Ehrlich in 1888.
• The term aplastic anemia was first introduced in 1904 by Chauffard
• A patient with aplastic anemia became the first recipient of successful allogeneic
bone marrow transplantation in 1972

4. INTRODUCTION
Pancytopenia with hypocellular Bone Marrow.

5. Causes of Pancytopenia

7. ACQUIRED Vs CONSTITUTIONAL
Features Acquired Constitutional
1. Age of presentation Any age Usually present in the first
decade of life  adulthood
2. Physical anomalies Absent Present(e.g. Shot stature ,upper
limb anomalies ,hypogonadism
, skin manifestations)
3. Family history No May be present

8. CONSTITUTIONAL APLASTIC ANEMIA
• FANCONI ANEMIA
• Most common form of inherited bone marrow failure
• AR inheritance
• Characterized by defects in DNA repair and a predisposition to leukemia and solid tumors.
• Anomalies : short stature, café au lait spots, and involving the thumb, radius, and genitourinary
tract.
• At least 16 different genetic defects
• Most common : type A Fanconi anemia - mutation in FANCA.

9. Cont..
• DYSKERATOSIS CONGENITA (DKC)
• Loss of function mutations of telomerase components
• Triad of abnormal skin pigmentation, nail dystrophy, and mucosal leukoplakia
• Inheritance : AD , AR , XR
• AR DKC : mutations of TERC or TERT
• XR DKC : mutations in the gene DKC1  dyskerin

10. Cont..
• INHERITED AMEGAKARYOCYTIC THROMBOCYTOPENIA
• characterized by severe thrombocytopenia and megakaryocyte absence at birth.
• Missense or nonsense mutations in the c-mpl gene
• SHWACHMAN-DIAMOND SYNDROME
• AR inheritance
• Characterized by pancreatic exocrine dysfunction, metaphyseal dysostosis, and bone marrow
failure

11. EPIDEMIOLOGY
• International Aplastic Anemia and Agranulocytosis Study (IAAAS), conducted in Europe and Israel,
in between 1980 and 1984
• Overall incidence : 2 cases per 1 million people
• The incidence may be 2-3 fold higher in SEA
• Age : children and young adults , 2nd small peak after age 60
• Genetic predisposition : HLA-DR2

12. ETIOLOGY

13. Cont..
• CHEMICALS: BENZENE
• Aplastic anemia , MDS , Leukemia
• RADIATION
• Dose dependent
• Direct toxicity to stem and progenitor cells.
• DNA damage  tissues susceptible to mitosis are highly affected.
• INFECTIONS
• Seronegative hepatitis ( Non-A , non-B , Non-C )
• EBV ( IMN )
• Human Parvovirus B19
• HIV

14. Cont..
DRUGS

15. • PREGNANCY
• Can occur during pregnancy or shortly after delivery.
• In women with a history of AA who had been treated into remission with IST, there is an
increased risk for relapse during pregnancy
• In contrast to idiopathic aplastic anemia, pregnancy-associated AA is often associated with
spontaneous remissions.
• IMMUNOLOGICAL DISEASES
• GVHD
• Eosinophilic fasciitis
• Thymoma , Hypogammaglobulinemia
• SLE

16. PATHOPHYSIOLOGY
• STEM CELLS
• Cells bearing the CD34 antigen, a marker of early hematopoietic cells, are greatly diminished
• In functional studies, committed and primitive progenitor cells are virtually absent.
• AUTOIMMUNITY
• The recovery of marrow function in pts prepared for BMT with ATG and Cycloserine
suggested that AA might be immune mediated.

17. Cont..
• CLONALITY
• Clonal hematopoietic stem cell disorders such as PNH and MDS frequently arise from AA.
• Increased survival following immunosuppressive therapy allows time for these underlying
clones to develop and expand.
• Up to 15% of children and adults with AA will develop MDS following IST, with monosomy 7
being the most common chromosomal abnormality.
• PNH results from the expansion of an abnormal hematopoietic stem cell that harbors a
somatic mutation of the X-linked gene, PIGA

18. CLINICAL FEATURES
• HISTORY
 Onset : Abrupt or insidious
 Bleeding usually the 1st presenting symptom.
 Infection is unusual 1st symptom ( unlike agranulocytosis where sore throat ,anorectal
abscess and sepsis occurs early )
 Proportional to the peripheral blood cytopenia and may include SOB, fatigue, easy
bruising, petechia, epistaxis, gingival bleeding, heavy menses, headache, and fever.
 Pts often feel and look remarkably well despite drastically reduced blood counts.
 Systemic complaints and weight loss should point to other etiologies of pancytopenia.
 Prior drug use, chemical exposure, and preceding viral illnesses.
 Family history

19. PHYSICAL EXAMINATION
• Petechiae, ecchymoses
• Pallor
• Lymphadenopathy and splenomegaly are highly atypical of AA.
• Café au lait spots and short stature suggest Fanconi anemia
• Peculiar nails and leukoplakia suggest dyskeratosis congenita
• Early graying (and use of hair dyes to mask it!) suggests a telomerase defect.

20. LAB DIAGNOSIS
• PBS
 Large RBCs , Paucity of platelets and granulocytes.
 MCV : commonly increased.
 Reticulocytes : absent or few
 The presence of immature myeloid forms suggests leukemia or MDS
 Nucleated RBCs suggest marrow fibrosis or tumor invasion
 Abnormal platelets suggest either peripheral destruction or MDS.

21. BONE MARROW
• A hypocellular bone marrow is required for the diagnosis of AA .
• 1-2 cm core biopsy is essential for assessing cellularity
• The presence of a small percentage of myeloid blasts or dysplastic features in the myeloid or
megakaryocyte lineages favors a diagnosis of hMDS.
• The % of CD34+ cells in the BM is often helpful : the % of CD34+ cells is usually ≤0.3% in AA,
whereas the CD34 % is either normal (0.5% to 1.0 %) or elevated in hMDS.
• Dry tap : Myelofibrosis , Myelopthisis

22. D/D OF HYPOCELLUR MARROW
1. Acquired AA
2. Inherited AA esp. Fanconi anemia
3. Hypoplastic MDS (hMDS) : 15% of MDS
4. Hypoplastic PNH

23. MDS Vs AA
Wintrobe’s clinical hematology 13th edidtion

25. Ancillary tests
• Chromosome breakage studies of peripheral blood using diepoxybutane or
mitomycin C : To R/O Fanconi anemia.
• Flow cytometry / FLAER of peripheral blood : To R/O PNH

26. CLASSIFICATION OF AA BASED ON SEVERITY OF
PANCYTOPENIA
• Severe aplastic anemia (SAA)
• Bone marrow cellularity <25% + 2/3 peripheral blood criteria:
• Absolute neutrophil count <500/mm3
• Platelet count <20,000/mm3
• Reticulocyte count <60,000/mm3 or <1% corrected reticulocyte count
• Very severe aplastic anemia (vSAA)
• Same as SAA with absolute neutrophil count <200/mm3
• Non severe (moderate aplastic anemia)
• Bone marrow cellularity <25%
• Peripheral blood cytopenia do not fulfill criteria for SAA

27. APPROACH TO AA

28. TREATMENT

29. Treatment cont..
• The risk of morbidity and mortality from AA correlates best with the severity of the cytopenia
rather than bone marrow cellularity.
• The 2-year mortality rate with supportive care alone for patients with SAA or VSAA approaches
80%, with invasive fungal infections and overwhelming bacterial sepsis being the most frequent
causes of death.
• NSAA is seldom life-threatening and in many instances requires no therapy

30. SUPPORTIVE CARE
• TRANSFUSIONS
 Pts with symptomatic anemia and/or thrombocytopenia a/w wet purpura or
bleeding require immediate BT.
 All transfusions in pts with suspected AA s/b irradiated to prevent transfusion-
associated GVHD.
 If the patient is a potential BMT candidate and is CMV negative or the CMV status is
unknown, CMV transmission should be avoided by either leukoreduction or the use
of CMV-negative products.
 Blood donation from family members should be avoided to prevent
alloimmunization that could also complicate future BMT

31. What is the target Hb and platelet ?
• Platelet : 10,000/cu mm
• Hb :7 g/dl ( 9 g/dl if there is ass. Cardiac or pulmonary disease)

32. Cont..
• ANTIBIOTICS
 Pts with ANC that are consistently <200μL, prophylaxis with oral antibiotics, such as a quinolone
and a triazole antifungal, is reasonable.
 Pts with febrile neutropenia s/b treated promptly with broad-spectrum antibiotics; in patients
with persistent fever after the initiation of antibacterial antibiotics, aspergillus coverage should be
added.
 Prophylaxis for PCP s/b given to all pts for at least 6 months after IST, BMT, or high-dose
cyclophosphamide therapy.

33. Cont..
• GROWTH FACTORS
• Should not be used in lieu of definitive therapy.
• They are often used after IST or high-dose cyclophosphamide therapy to accelerate
hematopoietic recovery.
• Their use has not been shown to improve survival.
• ATG+CSA+G-CSF identifies early non responders, and perhaps may indicate an urgent
transplant approach.

34. Definitive Therapy for Severe Aplastic Anemia
• BONE MARROW TRANSPLANTATION
 Allogeneic BMT from an HLA-matched sibling donor is the treatment of choice at most centers for
young patients <40 yrs.
 The age effect : Very strong age effect with survival of 82%, 72%, 53% for patients aged 1-20, 21-
40 and over 40 years , due to a higher incidence of graft failure and GvHD
 A major advantage of BMT over standard IST
 Marked reduction in the risk of relapse and
 Reduction in the outgrowth of late clonal disorders such as MDS and PNH.

36. • CONDITIONING REGIMEN
• Cyclophosphamide (50 mg/kg/day × 4 days) with or without ATG, is commonly used for
conditioning before SCT.
• Current guidelines from EBMT and the British Society for Standards in Haematolgy , call for a
combination of FLU-CY, combined with ATG (FCA) or alemtuzumab (CAMPATH) (FCC), for SAA
pts over the age of 30, receiving a matched sibling donor transplant.

37. Bone Marrow (BM) or Peripheral Blood (PB)??
• British guidelines, call for BM as a stem cell source, in ATG based conditioning and
• BM should be the only acceptable stem cell source for transplants from HLA
identical siblings in SAA.

38. Alternative Donor Bone Marrow Transplantation
• Unrelated donors and mismatched transplants have almost twice the transplant-related mortality
and risk of GVHD as matched sibling donor transplant.
• The ideal UD, is a male, HLA matched at the A,B,C,DRB1 loci, less than 30 years of age, CMV
matched with the recipient.
• The conditioning regimen would include FLU-CY-ATG (FCA) and low dose TBI, or FLU-CY-CAMPATH
(FCC) .

40. Unrelated Cord Blood(UCB) Transplant
• Indication : Pts who do not have a suitable UD.
• The conditioning regimen for CB transplants, is identical to the regimen which is proposed for UD
transplants, although MTX is omitted from GVHD prophylaxis of CB grafts; one dose of rituximab
150 mg is recommended on day+5, to prevent EBV lymphoproliferative disorders

41. Haploidentical(HAPLO) Transplant
• Young pts who do not have a matched UD or a suitable CB unit, and have failed at least one
course of IST, or have rejected a previous UD or CB graft, are eligible for a transplant from HLA
haploidentical family donors (HAPLO).
• Still in the experimental stage.

42. IMMUNOSUPPRESSIVE THERAPY(IST)
• ANTI-THYMOCYTE GLOBULIN(ATG)/CYCLOSPORIN(CSA ) BASED THERAPY
 Indication : Not a candidate for BMT because of older age or lack of a matched sibling donor.
 ATG is produced by immunizing animals (horse or rabbit) against human thymocytes.
 The largest experience is with horse ATG, although rabbit ATG has recently been approved for use
in the US.
 A RCT demonstrated that horse ATG/CSA is superior to rabbit ATG/CSA in terms of response at 6
months (68% vs 37%), and 3 year survival (96% vs 76%) .

44. IST cont..
 The response rates to ATG/CSA range between 60% and 80% , with 5-year survival rates
comparable to BMT.
 In contrast to BMT, most pts are not cured of their disease.
 Most pts respond within 6 to 12 wks after receiving ATG/CSA.
 ATG is usually given over 4 days but CSA must be continued for at least 6 to 12 months before
tapering the drug.
 Persistent cytopenia is common and many patients relapse, become dependent on cyclosporine,
or develop secondary clonal disease such as PNH or MDS.

45. IST cont..
• HIGH-DOSE CYCLOPHOSPHAMIDE
• High-dose cyclophosphamide remains (often in conjunction with ATG) is the most commonly
used BMT conditioning regimen for AA.
• Complete reconstitution of autologous hematopoiesis occurs in 10% to 15% of pts
undergoing allogeneic BMT for AA.
• 10-year survival (84%) in patients with autologous recovery was equivalent or better than in
patients who engrafted (74%)
• High-dose cyclophosphamide without BMT has been used to treat aplastic anemia patients
who lack a suitable donor

46. RELAPSED AND REFRACTORY SEVERE AA
• No standard algorithm
• As much as 30% to 40% of pts do not respond to initial therapy and another 20% to 40% of
responding patients relapse.
• Therapeutic options include
• Allogeneic BMT (usually from an unrelated or mismatched donor),
• Re-treatment with ATG/CSA,
• Alemtuzumab, or
• High-dose cyclophosphamide

47. ELTROMBOPAG (EPAG)
• Initial encouraging results in refractory pts
• EPAG has been used together with ATG +CSA , as initial treatment in 88 patients .
• The overall response at 6 months was 85%, with survival in the order of 90%.
• Cytogenetic abnormalities and clonal evolution to MDS occurred at a similar frequency compared
to standard IST.

48. TREATMENT OF PATIENT ABOVE THE AGE OF 60.
• BMT is rarely offered to pts > 60 years, due to high transplant related mortality.
• Pts between 60 and 70 years of age, s/b treated with conventional ATG+CSA along with G-CSF,
because of faster neutrophil recovery.
• Above the age of 70 or 80, pts are rather frail  use CSA plus androgens, and reserve CSA+ATG
for fit patients.

49. SUMMARY OF TREATMENT

50. REFERENCE
• Wintrobe’s clinical hematology 13th edition
• Harrison 19th edition
• Blood journal 2017,How I treat aplastic anemia

51. THANK YOU