actually for haemorrhagic newborn diseases, mainly focus of vit K def...the other is for revision n more commonly occur in child n adults....for haemolytic newborn disease, mainly focus on Rh disease n ABO incompatibility.....the other when childhoods

1. Haemorrhagic & Haemolytic Disease in
Newborn

2. Normal Haemostasis
5 main components:
1) Coagulation factors- activated when released of
Tissue Factor (TF) by vessel injury
2) Coagulation inhibitors- to prevent widespread
coagulation
3) Fibrinolysis- limits fibrin deposition
4) Platelets- aggregate at sites of vessel injury to form
primary haemostatic plug
5) Blood vessels- intact vascular endothelium secretes
PGI2 and NO which promote vasodilation & inhibit plt
aggregation. Damaged endothelium releases TF &
procoagulants (collagen & vWF).

4. Endpoint of coagulation cascade is
generation of thrombin.

6. Abnormal bleeding

7. Acquired disorders of coagulation
Secondary to
i. Vit K def.
ii. Liver disease
iii. ITP ( immune thrombocytopenia)
iv. DIC ( disseminated intravascular coagulation)

8. 1) Vit. K deficiency
• Essential for production of active forms of
factors II, VII, IX, X and anticoagulants such as
protein C & S
• Def d/t
– Inadequate intake
– Malabsorption ( coeliac dz, cystic fibrosis,
obstructive jaundice)
– Vit K antagonists (eg. Warfarin)

9. Pathogenesis
Conversion of PIVKA to Vit K converted to vit K
Non-functional proteins
biologically active forms epoxide which cycled
called PIVKA (proteins
with carboxylation of back to reduced form by
formed in vit. K absence)
glutamic acid reductases
Gamma-carboxylated
glutamic acid binds Ca
ions which forms a
complex with platelet
phospholipid

10. 2) Liver Disease
• Biliary obstruction impaired vit K absorption l/t
decrease synthesis FII,FVII,FIX and X.
• Severe hepatocellular dz, reduced FV, fibrinogen
& plasminogen activator.
• Dysfunctional fibrinogen (dysfibrinogenaemia)
• Low thrombopoietin production l/t
thrombocytopenia
• Hypersplenism associated with portal HTN l/t
thrombocytopenia

11. • Disseminated intravascular coagulation (DIC)
related to release of thromboplastins from
damaged liver l/t low conc. of antithrombin,
protein C, impaired removal activated clotting
factors & increase fibrinolytic activity.

12. 3) Immune Thrombocytopenia (ITP)
• Commonest cause of thrombocytopenia in
childhood
• Incidence of 4 per 100 000 children per year
• Caused by antiplt IgG autoantibodies
• Approx. 75% follows vaccination or infect.
such as chickenpox
• Associated with SLE, HIV, CLL, Hodgkin’s dz or
autoimmune haemolytic anemia

13. Clinical features
• Children ages of 2-10 years old
• Onsets 1-2 weeks after viral infection
• Petechiae
• Purpura
• Superficial bruising
• Epistaxis
• Intracranial bleeding (rare)

14. 4)Disseminated Intravascular
Coagulation (DIC)
• Coagulation pathway activation l/t diffuse
fibrin deposition in microvasculature and
consumption of coagulation factors & plts.
• Commonest causes are severe sepsis or shock
d/t circulatory collapse (in meningococcal
septicaemia or extensive tissue damage from
trauma or burns.

16. Pathogenesis
Triggered by entry of
Increased activity of
procoagulant material
tissue factor release
into circulation eg.
from damaged tissues
Severe trauma, liver
on tumour cells
disease
Initiated by widespread Deposition of fibrin in
endothelial damage & microcirculation,
collagen exposure eg. intravascular thrombin
Severe burns formation
Intense fibrinolysis
stimulated by thrombi
on vascular walls

17. Combined action of
Bleeding probs d/t
thrombin & plasmin
thrombocytopenia
cause depletion of
caused by consumption
fibrinogen and all
of plts
coagulation factors

18. Clinical Features
• Bleeding
• Generalized bleeding in GIT, oropharynx, into
lungs, urogenital tract and vaginal bleeding
particularly severe
• Skin lesions
• Renal failure
• Gangrene of toes
• Cerebral ischaemia

19. Inherited diseases
1) Haemophilia
• Commonest severe inhereted: haemophilia A
& haemophilia B
• X-linked recessive inheritance
• In haemophilia A, there is FVIII deficiency
• 1 in 5000 male births
• Haemophilia B (FIX def.)
• 1 in 30 000 male births

21. Clinical features
• Bleeding episodes most freq. in joints & m/s
• Crippling arthritis (recurrent spontaneous bleeding into
joints and m/s)
• Painful haemarthroses and m/s haematomas l/t
progressive joint deformity & disability
• Intracranial haemorrhage
• Bleeding post-circumsition
• Prolonged oozing from heel stick & venepuncture sites
• Spontaneous haematuria & GI haemorrhage
• Haemophilic pseudotumours

22. 4) Von Willibrand disease (vWD)
• Has 2 major roles:
– Facilitates plt adhesion to damaged endothelium
– Acts as carrier protein for FVIII:C
• Results from either qualitative or quantitaive def.
of vWD
• l/t defective plt plug formation and def. of FVIII:C
• Many different mutations in vWF gene and many
types of vWD
• Inheritance usually autosomal dominant
• Commonest subtype, type I (60-80%)

23. Classification
Type I
Quantitative partial def
Type II
Functional abnormality
Type III
Complete def

25. Clinical features
• Bruising
• Prolonged, excessive bleeding after surgery
• Epistaxis & menorrhagia (mucosal bleeding)
• Haematomas & haemarthroses (uncommon)

26. Hemorrhagic disease of newborn
Diagnosis
Investigation
Treatment
Management
Azizah Majid
HBA 10027653

27. Notes
• Vitamin K represents a group of lipophilic and
hydrophobic vitamins. The term vitamin K
originated from koagulations-vitamin in
German
• Vitamin K is a necessary cofactor for γ-
glutamyl carboxylase, the enzyme required for
posttranslational carboxylation of
prothrombin, FVII, FIX, and FX, and proteins C,
S, and Z.

28. Abstract on Haemorrhagic disease in newborn and older infants: a study in hospitalized
children in Kelantan, Malaysia.
Retrospective study:
epidemiology, CF, lab findings, Classical haemorrhagic disease
treatment and outcome of of the newborn was the
haemorrhagic disease in 42 commonest presentation (48%),
Kelantanese infants- Hospital followed by early onset (29%)
Universiti Sains Malaysia during a and late onset (24%) disease.
2-year period (1987-1988).
Home deliveries accounted for
All the infants had prolonged
81% of the affected infants. Commonest presenting CF:
prothrombin and partial
Most of these babies were not pallor, jaundice, umbilical cord
thromboplastin times which
given vitamin K at birth in bleeding, tense fontanelle,
were corrected by
contrast to those delivered in convulsions & hepatomegaly.
administration of vitamin K.
hospitals.
Subdural haemorrhage was the The overall case fatality rate:
commonest form of intracranial 14%. The results of this study
haemorrhage, followed by :emphasize the value of vitamin
subarachnoid haemorrhage. K prophylaxis in the newborn.

29. DDx of neonatal haemorrhagic
disorder
Vitamin K
Neonatal Platelet
Deficiency
Thrombocytopenia Abnormalities
Bleeding
Inherited
Coagulation Liver Disease
Disorders

30. Diagnosis
• The diagnostic criteria for vitamin K deficiency
bleeding include:
• Prolonged prothrombin time (PT)/Elevated international
normalized ratio (INR) (gold standard)
• Prolonged activated partial thromboplastin time (aPTT)
• Fibrinogen levels and a platelet count within in normal range for
newborns
• The diagnosis is confirmed if the INR normalizes
after administration of vitamin K and the bleeding
is stopped.

31. Why It Is Done
• The prothrombin time (PT) and international normalized ratio (INR) are
measures of the extrinsic pathway of coagulation ( INR is a calculation made to
standardize prothrombin time. INR is based on the ratio of the patient's
prothrombin time and the normal mean prothrombin time)
• PT measures factors I (fibrinogen), II (thrombin), V, VII, and X.
• It is used in conjunction with the activated partial thromboplastin time (aPTT)
which measures the intrinsic pathway
• Blood clotting factors: blood to clot (coagulation).
• Prothrombin, or factor II, made by the liver. Vitamin K is needed to make it &
other clotting factors.
The prothrombin time can be prolonged as a result of deficiencies in vitamin K,
warfarin therapy, malabsorption, or lack of intestinal colonization by bacteria
(such as in newborns). In addition, poor factor VII synthesis (due to liver
disease) or increased consumption (in disseminated intravascular coagulation)
may prolong the PT.

32. Tests and Exams
• Significant bleeding in neonates should prompt clinical
evaluation.
• ‘Initial empirical therapy consists of platelet and/or
factor supplementation, which is often administered
while diagnostic studies are under way’
• Laboratory evaluation of the hemorrhage in newborns
should include
 Sepsis evaluation
 determination of the ( Blood clotting tests) platelet
count, PT, aPTT, TT, and fibrinogen concentration.

33. Cont..
IMAGING STUDIES
• Ultrasound-intracranial bleeding
– rare and usually associated with other causes of bleeding,
particularly thrombocytopenia
• MRI
– exposes the neonate to no radiation
– becoming the preferred way to study the brain because tissue
damage can be better defined.

34. Cont..
PROCEDURES
• If the cause of bleeding is not straight forward, the
caregiver may need to perform other procedures like
endoscopic retrograde cholangiopancreatography
[ERCP] to rule out hepatobiliary diseases.
HISTOLOGIC FINDINGS
• If liver biopsy is indicated, histopathology with and
without special stains or biochemical analyses may be
helpful to rule out hepatitis, biliary atresia, tumors, and
inherited metabolic diseases of the liver.

35. Cont…
• Genotype analysis(GA) : Congenital vitamin K
deficiency is an autosomal recessive disorder
that occurs because of mutations in the genes
encoding γ-glutamyl carboxylase or vitamin
K2,3–epoxide reductase complex. Neonates
with this disorder often have severe bleeding,
including IntraCranial Haemorrhage. GA to
confirm the defect.

36. Tx & Management
• Vitamin K :for prevention of & tx of vit. K deficiency
bleeding (VKDB). Other coagulation factors are rarely
needed.
• Severe bleeding: use of fresh frozen plasma.
• No other drugs or treatments are acceptable
substitutes for prompt vitamin K dosing.
• Subcutaneous administration of vit. K is preferred over
the intramuscular (IM) route in symptomatic infants.

37. Cont…
SURGICAL CARE
• Normally, vitamin K deficiency bleeding
infants do not require surgical care but in rare
cases, an infant may need neurosurgical
evaluation and treatment.
• Other conditions, such as those associated
with short bowel syndrome and hepatobiliary
disease may require surgical evaluation

38. Potential Complications
• Bleeding inside the skull (intracranial
hemorrhage), with possible brain damage
• Death
• Severe bleeding

39. Prevention
• Many newborns- deficient in vit. K, whether measured in cord blood or
indirectly by measuring the levels of vitamin K–dependent coagulation
proteins. Recommends giving every baby a shot of vitamin K immediately
after birth. This practice has helped prevent the condition.
• The early onset form of the disease may be prevented by giving vitamin K
shots to pregnant women who take anti-seizure medications.(mechanisms
by which anticonvulsant drug l/t vit. K deficiency bleeding in neonates :not
clearly understood)
• Most infants born to well-nourished mothers have adequate
vitamin stores at birth
– Vitamin K is naturally produced by intestinal bacteria which newborn’s lack
resulting in the deficiency
– Suppression of intestinal bacteria by various antibiotics is responsible for this
deficiency
– Infants receive Vitamin K either orally or intramuscularly

40. Prognosis (Outlook)
• The outlook tends to be worse for babies with
late onset hemorrhagic disease than other
forms. There is a higher rate of bleeding inside
the skull (intracranial hemorrhage) associated
with the late onset condition.

41. RECOMMENDED VALUE
• There is no upper limit to vitamin K because of its
low toxicity
– Infants 0-6 months = 2 µg
– Infants 7-12 months = 2.5 µg
– Children 1-3 years = 30 µg
– Children 4-8 years = 55 µg
– Children 9-13 years = 60 µg
– Adolescents 14-18 years = 75 µg

43. HAEMOLYTIC DISEASE IN
NEWBORN

44. • Haemolytic anemia is characterised by reduced red cell
lifespan due to increased red cell destruction in the
circulation (intravascular haemolysis) or liver/spleen
(extravascular haemolysis)
• In haemolysis, red cell survival may be reduced to a
few days but bone marrow production can increase
about 8-fold, so haemolysis only lead to anemia when
bone marrow is no longer able to compensate for the
premature destruction of red cells

45. Common causes
• RhD incompatibility
• ABO incompatibility

46. Rare causes
• Maternal autoimmune disease such as autoimmune
hemolytic anemia or systemic lupus erythematosus: maternal
antibodies enter fetal circulation and result in fetal or infant
erythrocyte destruction
• Minor blood group antigen incompatibility (Kell, Duffy, M, S)
• Drug-induced hemolysis such as from penicillin or acyclovir
• Infection such as from cytomegalovirus, toxoplasmosis,
syphilis, or sepsis
• Disseminated intravascular coagulation
• Hereditary erythrocyte disorders such as hereditary
spherocytosis/elliptocytosis, thalassemia, glucose-6-
phosphate dehydrogenase deficiency, pyruvate kinase
deficiency
• Metabolic abnormalities such as acidosis or galactosemia
• Angiopathic hemolysis such as cavernous hemangioma, large
vessel thrombi, renal artery stenosis, or severe coarctation of
the aorta

47. ISOIMMUNIZATION
Rh disease
ABO incompatibility

48. 1. Rh disease
• Rhesus disease is a condition which affects an unborn baby when
its mother’s immune system generates antibodies which attack the
baby’s red blood cells.
• Prevalence of genotype varies with the population. Rh negative
individuals comprise 15% of Caucasians, 5.5% of African Americans,
and <1% of Asians.
• For Rh (D) disease to develop in an unborn baby, two conditions
must be met.
– a woman with the Rhesus-negative blood type is pregnant with a baby
who has Rhesus-positive blood.
– the pregnant woman must have previously been exposed to Rhesus-
positive blood. This second condition must be met in order for the
woman’s immune system to generate antibodies to the Rhesus-
positive blood cells of the baby.

51. • Rhesus disease only affects the baby. It will not cause
any symptoms for the mother.
• In the unborn baby, they may become anemic which
can be measured by Doppler ultrasound (blood thinner
and flow quickly)
• In the newborn baby this may cause:
– Anemia with/without jaundice
– increased breathing rate
– poor muscle tone
– poor feeding
• Wont always have obvious symptoms when they are
born. Symptoms can develop up to three months
afterwards.

52. • If rhesus disease causes severe anemia in the fetus, it
can also cause:
– fetal heart failure
– fluid retention
– swelling (oedema)
– Stillbirth
• In newborn baby:
– Kernictus (deafness, blindness, brain damage, learning
difficulties, death)

53. Investigation…
• Maternal
– Kleihauer-Betke / flow cytometry
• Can confirm that fetal blood has pass into maternal
circulation
• Estimate the amount of fetal blood has passed into
maternal circulation
– Indirect Coombs test
• Screen blood from antenatal women for IgG ab that
may pass through the placenta and cause HDN

54. • Unborn baby
– Doppler ultrasound
– Fetal blood sampling (FBS)
• Newborn baby
– Direct Coombs test
• Evidence of anti-D ab that have cross placenta
– FBC
• Hb level and platelet count
– Bilirubin

57. Treatments…
• Unborn baby
– Intrauterine blood transfusion (IUT)
• Newborn baby
– Phototherapy
– Exchange transfusion
– Intravenous immunoglobulin (IVIG)
• Prevent destruction of RBC

60. Preventions…
• All non-sensitized Rh D-negative women should be given anti-
D immunoglobulin at 28 and 34 weeks of gestation to reduce
risk of sensitization from fetomaternal haemorrhage.
• At birth, if the baby is Rh –ve, no further treatment needed.
•
• If baby is Rh +ve, prophylactic anti-D should be administered
within 72h of delivery.

61. 2. ABO Incompatibility
• ABO incompatibility is the most common
cause of hemolytic disease of the newborn.
• Approximately 15% of live births are at risk,
but manifestations of disease develop in only
0.3-2.2%.

62. 2. ABO Incompatibility
• With maternal blood types A and B, isoimmunization does not occur
because the naturally occurring antibodies (anti-A and -B) are IgM, not
IgG.
• In type O mothers, the antibodies are predominantly IgG, cross the
placenta and can cause hemolysis in the fetus.
• The association of a type A or B fetus with a type O mother occurs in ~15%
of pregnancies. However, HDN occurs in only 3%, is severe in only 1%, and
<1:1,000 require exchange transfusion.
• Unlike Rh, ABO disease can occur in first pregnancies, because anti-A and
anti-B antibodies are found early in life from exposure to A- or B-like
antigens present in many foods and bacteria.
• Clinical presentation: generally less severe than with Rh disease.

64. • Diagnosis and investigation are same as Rh
disease.
• Treatment are by phototherapy and exchange
transfusion.
• There is no effective prevention against ABO
incompatibility reaction.

66. Differential diagnosis
• Hemorrhage in the newborn
• Failure of erythrocyte production in the
newborn
• Conjugated hyperbilirubinemia

67. AUTOIMMUNE HEMOLYTIC
ANEMIA
anemia secondary to premature
destruction of red blood cells (RBCs)
caused by the binding of autoantibodies
and/or complement to RBCs

68. ISOIMMUNE VS AUTOIMMUNE
• The most important immune hemolytic
disorder in pediatric practice is hemolytic
disease of the newborn (erythroblastosis
fetalis), caused by transplacental transfer of
maternal antibody active against the RBCs of
the fetus, that is, isoimmune hemolytic
anemia
• Various other immune hemolytic anemias are
autoimmune

69. Pathogenesis
• abnormal antibodies are directed against RBC
membrane antigens, but the pathogenesis of antibody
induction is uncertain.
• The autoantibody may be produced as an
inappropriate immune response to an RBC antigen or
to another antigenic epitope similar to an RBC antigen,
known as molecular mimicry.
• Alternatively, an infectious agent may alter the RBC
membrane so that it becomes “foreign” or antigenic to
the host. The antibodies usually react to epitopes
(antigens) that are “public” or common to all human
RBCs, such as Rh proteins.

70. AIHA
• caused by autoantibody-induced hemolysis
(the premature destruction of circulating red
blood cells);
– usually idiopathic,
– SECONDARY, associated with
1. infection,
2. lymphoproliferative disorders,
3. autoimmune diseases
4. drugs

71. CLASSIFICATION
• Based on etiology:
– Warm antibody mediated: immunoglobulin (Ig) G (often
idiopathic or associated with leukemia, lymphoma, thymoma,
myeloma, viral infections, and collagen-vascular disease)
– Cold antibody mediated: IgM and complement in majority of
cases (often idiopathic; at times associated with infections,
lymphoma, or cold agglutinin disease)
– Drug induced: three major mechanisms:
1. Antibody directed against Rh complex (e.g., methyldopa)
2. Antibody directed against RBC-drug complex (hapten induced;
e.g., penicillin)
3. Antibody directed against complex formed by drug and plasma
proteins; the drug-plasma protein-antibody complex causes
destruction of RBCs (innocent bystander; e.g., quinidine)

72. warm cold
autoantibody
immunoglobin G (IgG) chronic cold agglutinin disease:
attacks red blood cells cold-activated immunoglobin M (IgM) and
(RBCs); patients are complement (C3d) coat RBCs and trigger hemolysis;
patients usually over age 50; sometimes resolves with
usually over age 50; cold avoidance; rarely progresses to renal failure
typically treated with
corticosteroids and
therapies for underlying
diseases Paroxysmal cold hemoglobinuria (PCH):
rare disease induced most often by postviral Donath-
Landsteiner autoantibody at cold temperatures in
children; often acute and severe, though usually short-
lived and self-limited; rarely progresses to renal failure,
frank lymphoma, or death

73. CAUSES

74. Warm AIHA
• Idiopathic: warm autoantibody IgG, its
complement (C3d), or both, coat the red cell
membrane and at 37°C induce phagocytosis
• Secondary: warm antibodies produced by
– lymphoproliferative disorders (e.g. non-Hodgkin's
lymphoma, chronic lymphocytic leukemia (CLL);
– collagen vascular/autoimmune diseases
(e.g. systemic lupus erythematosus (SLE)
– HIV infection

75. Cold agglutinin disease
• Idiopathic: the IgM autoantibody has an affinity for
RBCs at cold temperatures (0ºC-18ºC); at warmer
temperatures (37ºC, or 98.6ºF), when the two have no
particular affinity, the IgM antibody can come off the
RBC, but the remaining complement sticks. Hemolysis
occurs as the liver and spleen remove complement-
coated RBCs
• Secondary: cold autoantibodies produced by
– infections such as Epstein-Barr virus, Mycoplasma
pneumoniae, and infectious mononucleosis
– lymphoproliferative disorders, such as non-Hodgkin's
lymphoma and chronic lymphocytic leukemia (CLL)

76. Paroxysmal cold hemoglobinuria
• Idiopathic: Donath-Landsteiner autoantibody
• Secondary: viral infections (particularly in
children and young adults), which produce the
Donath-Landsteiner antibody

77. Predisposing factors
• B-cell malignancy (produces hemolysis-inducing
autoantibodies)
• Family or personal history of autoimmune
disease (produces hemolysis-inducing
autoantibodies)
• Viral infection in children (produces the Donath-
Landsteiner autoantibody, which induces PCH)
• Cold temperature (induces IgM activation in cold
agglutinin disease)

78. Symptoms
Common for all AIHA:
• Fatigue, dyspnea, malaise
• Light-headedness or dizziness
• Feeling hot and cold, or shivering (fever)
• Abdominal/back pain
• Occasionally abdominal fullness due to
splenomegaly
• Jaundice and dark urine

79. Specific for cold agglutinin disease:
• Episodes of jaundice and dark urine
• Acrocyanosis of hands, feet, earlobes, and/or
tip of nose
• Exposure to cold will precipitate symptoms
Specific for paroxysmal cold hemoglobinuria:
• Paroxysms of hemoglobinuria on exposure to
cold

80. Signs
Common for all AIHA:
• Low hematocrit (<40% in males; <37% in females)
• Pallor
• Tachycardia, palpitations of the heart, and soft systolic murmurs
• Jaundice, usually mild
• Dark urine
• Reticulocytosis
• Palpable spleen/splenomegaly, especially if chronic (often secondary to B-
cell malignancy)
• Fever, secondary to underlying malignancy or infection
• Weight loss, secondary to underlying malignancy
• Secondary rash/petechiae/ecchymoses
• Congestive heart failure (occasionally)

81. Specific for warm autoimmune hemolytic anemia:
• Positive direct Coombs test previously reported in
patient referred for transfusion
Specific for chronic cold agglutinin disease:
• Skin findings include cool tips of the hands, feet,
earlobes, and/or nose
• Splenomegaly is common
• Hemoglobinuria at cold temperatures in some patients
Specific for paroxysmal cold hemoglobinuria:
• Severe anemia
• Hemoglobinuria
• Hemoglobinemia
• Renal failure

82. Investigation tests
In the differential diagnosis of AIHA, first determine whether
there is anemia, then whether there is hemolysis.
Order of tests
• CBC with reticulocyte count
• Peripheral blood smear
• Urine dipstick for blood
• Liver function tests for bilirubin
• Liver function tests for serum lactate dehydrogenase (LDH)
• Haptoglobin
• Direct Coombs test
• Cold agglutinin titer
• Donath-Landsteiner autoantibody

83. Test Finding
CBC with reticulocyte count hemoglobin and hematocrit vary in AIHA, but
typically are low; the reticulocyte count, typically
elevated in AIHA, is the hallmark indicator of red cell
destruction
Liver function tests bilirubin and LDH are breakdown products of
for bilirubin and serum lactate hemoglobin; elevated levels provide additional
dehydrogenase (LDH) evidence of RBC destruction
Haptoglobin binds in plasma with free hemoglobin when RBCs
are destroyed; depressed haptoglobin provides
additional evidence of hemolysis
Urine dipstick for blood may be helpful to diagnose intravascular hemolysis
by detecting hemoglobinuria
If tests point to hemolytic anemia, then conduct
further tests to determine whether the HA is caused
by the hallmark autoantibodies of AIHA. Finally, if
tests point to AIHA, prepare further tests to
determine which specific autoantibody (IgG, IgM, or
IgA) and/or complement is responsible for hemolysis
(i.e. which specific AIHA is afflicting the patient).

84. Peripheral blood smear critical to the diagnosis of any anemia, it shows the
number and morphology of different cell lines, and
provides the visual evidence of hemolysis. In all warm
AIHAs, macrophages transform disc shape of healthy RBCs
to telltale spherocytes. Classically, reticulocytosis and
nucleated red blood cells are also apparent. Examination of
white blood cells and platelets provides clues to diagnosing
hematologic or malignant disorders that sometimes coexist
with AIHA. RBC aggregation on the smear suggests the
diagnosis of cold AIHA
Direct Coombs test positive test indicates presence of autoantibodies (attached
to RBCs); if positive, prepare an antibody eluate and
examine the specificity for known RBC antigens
Indirect Coombs test: positive test indicates the presence of
autoantibodies (not attached to the RBCs)
Thermal amplitude of the cold agglutinin indicates whether
the antibody can bind RBC at physiologically relevant
temperatures
Donath-Landsteiner If paroxysmal cold hemoglobinuria is suspected, confirm
autoantibody diagnosis with test for hallmark Donath-Landsteiner
autoantibody

85. Cold agglutinin titer useful if suspect cold agglutinin disease,
in which titer usually is very high (from
>1000 to >1:105). Titer does not predict
severity of disease
Urine hemosiderin staining the urine with Prussian blue or
other iron stain can indicate whether
there is hemosiderin present in the urine.
If positive, this indicates possible
hemolysis; however, other conditions of
iron overload may also result in increased
hemosiderin

86. Summary

87. Warm AIHA
• Direct Coombs test is positive for immunoglobulin G
(IgG), complement (C3d), or both
• Spherocytes present on the peripheral blood smear
• Phagocytized RBCs are typically sequestered in the
spleen
• Most patients quickly respond to corticosteroids,
though the disorder is chronic and often relapsing
• Refractory cases require prolonged
immunosuppression or may undergo splenectomy; life-
threatening cases may require transfusion

88. Chronic cold agglutinin disease
• Positive direct Coombs test rarely detects cold-reactive IgM, but always
detects C3d bound to RBC membrane
• RBC aggregates seen on peripheral blood smear
• Typically, cold agglutinin titer is very high
• Idiopathic form of disease is frequently recurrent condition and often
responds to cold avoidance; exacerbations are intermittent
• Critical to explore diagnosis of B-cell lymphoma, which will determine
therapy
• Corticosteroids are usually not helpful
• Splenectomy is rarely beneficial (unless splenic lymphoma) because RBCs
destroyed primarily by C3d activation are sequestered in the liver, not
spleen
• In presence of B-cell neoplasm, chemotherapy or immunotherapy may
help
• Exposure to cold can prompt sudden drop in hematocrit and induce renal
failure

89. Paroxysmal cold hemoglobinuria
• Diagnosis generally relies on clinical presentation; routine tests do not pick
up pathological Donath-Landsteiner autoantibody
• Most often appears postviral in children and young adults
• Symptoms may include fever, chills, abdominal distress, nausea, leg/back
pain
• Signs may include jaundice and hemoglobinuria
• IgG detected in serum
• Direct Coombs test is usually negative for pathological IgG and
complement
• Indirect Coombs test is negative
• Diagnosis is confirmed with test for hallmark Donath-Landsteiner
autoantibody
• Often acute and severe, but usually short-lived and self-limited
• Treatment includes: cold avoidance; supportive care; transfusions to
alleviate symptoms; corticosteroids rarely useful
• In rare cases can progress to renal failure

90. RED CELL ENZYME DISORDER
G6PD deficiency

91. • G6PD
– Rate-limiting enzyme in the pentose phosphate
pathway
– Essential for preventing oxidative damage to red
cells
• Def
– susceptible to oxidant-induced haemolysis
– X-linked, predominantly affect males

93. • Kids with G6PD deficiency typically do not show any
symptoms of the disorder until their red blood cells are
exposed to certain triggers.
• Clinical features:
– Sudden rise of body temperature and yellow coloring of
skin and mucous membrane.
– Dark yellow-orange urine.
– Pallor, fatigue, general deterioration of physical conditions.
– Heavy, fast breathing.
– Weak, rapid pulse.
• Once the trigger is removed or resolved, the symptoms
of G6PD deficiency usually disappear fairly quickly,
typically within a few weeks.

95. Investigations…
• Bilirubin level (high)
• Complete blood count, including red blood cell
count
• Hemoglobin – blood (low)
• Haptoglobin level (low)
• Methemoglobin reduction test
• Reticulocyte count (high)
• Blood film (concentrated and fragmented cells,
‘bite’ cells and ‘blister’ cells)

97. Management…
• Medicines to treat an infection, if present
• Stopping any drugs that are causing red blood
cell destruction
• Transfusions, in some cases