6. TABLE 13-2 -- Adult Reference Ranges for Red Blood Cells
Measurement (units)
Hemoglobin (gm/dL)
Men
13.6ā17.2
39ā49
Hematocrit (%)
Red cell count (10 /ĀµL)
6
Women
12.0ā15.0
33ā43
4.3ā5.9
3.5ā5.0
Reticulocyte count (%)
0.5ā1.5
Mean cell volume (Āµm ) MCV
82ā96
Mean corpuscular hemoglobin (pg) MCH
27ā33
Mean corpuscular hemoglobin
concentration (gm/dL) MCHC
33ā37
3
RBC distribution width
11.5ā14.5
7.
8. WHERE is MARROW?
ā¢ Yolk Sac: very early embryo
ā¢ Liver, Spleen: NEWBORN
ā¢ BONE
ā CHILDHOOD: AXIAL SKELETON & APPENDICULAR
SKELETON BOTH HAVE RED (active) MARROW
ā ADULT: AXIAL SKELETON RED MARROW,
APPENDICULAR SKELETON YELLOW MARROW
12. ANEMIAS*
ā¢ BLOOD LOSS
ā ACUTE
ā CHRONIC
ā¢ IN-creased destruction (HEMOLYTIC)
ā¢ DE-creased production
* A good definition would be a decrease in OXYGEN CARRYING
CAPACITY, rather than just a decrease in red blood cells, because
you need to have enough blood cells THAT FUNCTION, and not just
enough blood cells.
13. Features of ALL anemias
ā¢ Pallor, where?
ā¢ Tiredness
ā¢ Weakness
ā¢ Dyspnea, why?
ā¢ Palpitations
ā¢ Heart Failure (high output), why?
14. Blood Loss
Acute: trauma
Chronic: lesions of gastrointestinal tract,
gynecologic disturbances. The features of
chronic blood loss anemia are the same as iron
deficiency anemia, and is defined as a situation
in which the production cannot keep up with
the loss.
16. IMPAIRED PRODUCTION
ā¢ Disturbance of proliferation and differentiation
of stem cells: aplastic anemias, pure RBC aplasia,
renal failure
ā¢ Disturbance of proliferation and maturation of
erythroblasts
ā¢ Defective DNA synthesis: (Megaloblastic)
ā¢ Defective heme synthesis: (Fe)
ā¢ Deficient globin synthesis: (Thalassemias)
23. FEATURES of G6PD Defic.
ā¢ Genetic: X-linked
ā¢ Can be triggered by foods (fava beans),
oxidant substances drugs (primaquine,
chloroquine), or infections
ā¢ HGB can precipitate as HEINZ bodies
ā¢ Acute intravascular hemolysis can occur:
ā Hemoglobinuria
ā Hemoglobinemia
ā Anemia
24. Sickle Cell Disease
ā¢ Classic hemoglobinopathy
ā¢ Normal HGB is Ī±2 Ī²2:
Ī²-chain defects (Val>Glu)
ā¢ Reduced hemoglobin āsicklesā in homozygous
ā¢ 8% of American blacks are heterozygous
25. Clinical features of HGB-S disease
ā¢
ā¢
ā¢
ā¢
Severe anemia
Jaundice
PAIN (pain CRISIS)
Vaso-occlusive disease: EVERYWHERE, but
clinically significant bone, spleen
(autosplenectomy)
ā¢ Infections: Pneumococcus, Hem. Influ.,
Salmonella osteomyelitis
26.
27. THALASSEMIAS
ā¢ A WIDE VARIETY of diseases involving GLOBIN synthesis,
COMPLEX genetics
ā¢ Alpha or beta chains deficient synthesis involved
ā¢ Often termed MAJOR or MINOR, depending on severity,
silent carriers and ātraitsā are seen
ā¢ HEMOLYSIS is uniformly a feature, and microcytic anemia,
i.e, LOW MCV (just like iron deficiency anemia has a low
MCV)
ā¢ A ācrew cutā skull x-ray appearance may be seen in severe
erythroid hyperplasia.
28.
29. Hemoglobin H Disease
ā¢ Deletion of THREE alpha chain genes
ā¢ HGB-H is primarilly Asian
H
HIGH
ā¢ HGB- has a
affinity for
oxygen
ā¢ HGB-H is unstable and therefore has
classical hemolytic behavior
30. HYDROPS FETALIS
ā¢ FOUR alpha chain genes are deleted, so this is
the MOST SEVERE form of thalassemia
ā¢ Many/most never make it to term
ā¢ Children born will have a SEVERE hemolytic
anemia as in the erythroblastosis fetalis of Rh
disease:
ā Pallor (as in all anemias), jaundice, kernicterus
ā Edema (hence the name āhydropsā)
ā Massive hepatosplenomegaly (hemolysis)
32. Immunohemolytic Anemia
ā¢ All of these have the presence of antibodies
and/or compliment present on RBC surfaces
ā¢ NOT all are AUTOimmune, some are caused
by drugs
ā¢ Antibodies can be
ā WARM AGGLUTININ (IgG)
ā COLD AGGLUTININ (IgM)
ā COLD HEMOLYSIN (paroxysmal) (IgG)
33. IMMUNOHEMOLYTIC ANEMIAS
ā¢ WARM AGGLUTININS (IgG), will NOT hemolyze at
room temp
ā Primary Idiopathic (most common)
ā Secondary (Tumors, especially leuk/lymph, drugs)
ā¢ COLD AGGLUTININS: (IgM), WILL hemolyze at
room temp
ā Mycoplasma pneumoniae, HIV, mononucleosis
ā¢ COLD HEMOLYSINS: (IgG) Cold Paroxysmal
Hemoglobinuria, hemo-LYSIS in body, ALSO often
follows mycoplasma pneumoniae
34. COOMBS TEST
ā¢ DIRECT: Patientās CELLS are
tested for surface Abās
ā¢ INDIRECT: Patientās SERUM is
tested for Abās.
37. MEGALOBLASTIC ANEMIAS
ā¢ Differentiating megaloblasts
(marrow) from macrocytes
(peripheral smear, MCV>94)
ā¢ Impaired DNA synthesis
ā¢ For all practical purposes,
also called the anemias of
B12 and FOLATE deficiency
ā¢ Often VERY
hyperplastic/hypercellular
marrow* (* exception to the
rule)
38. Decreased intake
Inadequate diet, vegetarianism
Impaired absorption
Intrinsic factor deficiencyāā
Pernicious anemiaāāāā
Gastrectomyāāāā
Malabsorption statesāā
Diffuse intestinal disease, e.g., lymphoma, systemic sclerosis
Ileal resection, ileitisāā
Competitive parasitic uptakeāā
Fish tapeworm infestationāāāā
Bacterial overgrowth in blind loops and diverticula of bowel
Increased requirement
Pregnancy, hyperthyroidism, disseminated cancer
39. Vit-B12 Physiology
ā¢ Oral ingestion
ā¢ Combines with INTRINSIC FACTOR in
the gastric mucosa
ā¢ Absorbed in the terminal ileum
ā¢ DEFECTS at ANY of these sites can
produce a MEGALOBLASTIC anemia
40. Please remember that ALL
megaloblastic anemias are also
MACROCYTIC (MCV>94 or
MCV~100), and that not only are
the RBCās BIG and
hyperplastic/hypercellular, but so
are the neutrophils, and
neutrophilic precursors in the
bone marrow too, and even more
so, HYPERSEGMENTED!!!
43. Fe Deficiency Anemia
ā¢ Due to increased loss or decreased
ingestion, almost always, in USA,
nowadays, increased loss is the reason
ā¢ Microcytic (low MCV), Hypochromic
(low MCHC)
ā¢ THE ONLY WAY WE CAN LOSE IRON IS
BY LOSING BLOOD, because FE is
recycled!
49. Anemia of Chronic Disease*
ā¢ CHRONIC INFECTIONS
ā¢ CHRONIC IMMUNE
DISORDERS
ā¢ NEOPLASMS
ā¢ LIVER, KIDNEY failure
* Please remember these patients may very very much
look like iron deficiency anemia, BUT, they have
ABUNDANT STAINABLE HEMOSIDERIN in the marrow!
50. APLASTIC ANEMIAS
ā¢ ALMOST ALWAYS involve platelet and
WBC suppression as well
ā¢ Some are idiopathic, but MOST are
related to drugs, radiation
ā¢ FANCONIās ANEMIA is the only one that
is inherited, and NOT acquired
ā¢ Act at STEM CELL level, except for
āpureā red cell aplasia
58. THROMBOCYTOPENIAS
ā¢ Like RBCs:
ā DE-creased production
ā IN-creased destruction
ā Sequestration (Hypersplenism)
ā Dilutional
ā¢ Normal value
150K-300K
66. Thrombotic Microangiopathies
ā¢ BOTH are very SERIOUS CONDITIONS with a
HIGH mortality:
ā TTP (THROMBOTIC THROMBOCYTOPENIC PURPURA)
ā H.U.S. (HEMOLYTIC UREMIC SYNDROME)
ā¢ These can also be called āconsumptiveā
coagulopathies, just like a DIC
69. BLEEDING DISORDERS due to
CLOTTING FACTOR DEFICIENCIES
ā¢ NOT spontaneous, but following surgery or trauma
ā¢ ALL factor deficiencies are possible
ā¢ Factor VIII and IX both are the classic X-linked
recessive hemophilias, A and B, respectively
ā¢ ACQUIRED disorders often due to Vitamin-K
deficiencies (II, VII, IX, X)
ā¢ von Willebrand disease the most common, 1%
70. ā¢
ā¢
ā¢
ā¢
ā¢
ā¢
von Willebrand Disease
1% prevalence, most common bleeding disorder
Spontaneous and wound bleeding
Usually autosomal dominant
Gazillions of variants, genetics even more complex
Prolonged BLEEDING TIME, NL platelet count
vWF is von Willebrand Factor, which complexes with
Factor VIII, to join platelets with the exposed ECM in
endothelial disruption. it is the von Willebrand Factor
which is defective in von Willebrand disease
ā¢ Usually BOTH platelet and FactorVIII-vWF disorders are
present
72. ā¢
ā¢
ā¢
ā¢
ā¢
ā¢
HEMOPHILIA A
The āclassicā HEMOPHILIA
Factor VIII decreased
Co-factor of Factor IX to activate Factor X
Sex-linked recessive
Hemorrhage usually NOT spontaneous
Wide variety of severities
ā¢ Prolonged PTT (intrinsic) only
ā¢ Rx: Recombinant Factor VIII
73. ā¢
ā¢
ā¢
ā¢
ā¢
HEMOPHILIA B
The āChristmasā HEMOPHILIA
Factor IX decreased
Sex-linked recessive
Hemorrhage usually NOT spontaneous
Wide variety of severities
ā¢ Prolonged PTT (intrinsic) only
ā¢ Rx: Recombinant Factor IX
75. DIC, Disseminated INTRA-vascular,
Coagulation
ā¢ Extremely SERIOUS condition
ā¢ NOT a disease in itself but secondary to many
conditions
ā Obstetric: MAJOR OB complications, toxemia, sepsis,
abruption
ā Infections: Gm-, meningococcemia, RMSF, fungi,
Malaria
ā Many neoplasms, acute promyelocytic leukemia
ā Massive tissue injury: trauma, burns, surgery
ā¢ āConsumptiveā coagulopathy
76. Common Coagulation TESTS
ā¢ PTT (intrinsic)
ā¢ PTļ INR (extrinsic)
ā¢ Platelet count, aggregation
ā¢ Bleeding Time, so EASY to do
ā¢ Fibrinogen
ā¢ Factor Assays
Classical RBCās and platelets, as in in the lab or your office with WRIGHTās stain.
Classical features of peripheral white cells
Erythroblasts (normoblasts) seen in the marrow and/or the peripheral smear.
HGB X 3 = HCT, a rough rule of thumb
Bone marrow biopsy stained with H&E (left), and smear stained with Giemsa (right). BOTH have special advantages!
This is a very intense slide, you may have to write a lot of stuff down and listen well!
This is the basis on which I was trained, and have been reading bone marrows all my life.
One logical (blood loss), two functional (ā dest, āprod) concepts.
Platelet analogy also
Losses occur when the rate of destruction is greater then the rate of production, i.e., the rate of production canāt keep up with the rate of destruction!
MCV = 80-95
MCHC = 33-37
To understand why there is an erythroid HYPER-plasia in marrows, with patients having HEMOLYTIC anemias, is CRITICAL!
Would you say all the above levels mean that these are good tests for hemolysis? YES
How about hemoglobinuria too? YES
Which one would be more likely to produce hemoglobinuria? ANS: INTRA-
The most common reason for a DECREASED M:E ratio with a NORMAL marrow cellularity might be a hemolytic anemia, although a DECREASE in the M cells (myeloid) would also cause this, especially if the cellularity was DE-creased. Please understand this!
Note lack of a central pallor and a microcytosis, i.e., low MCV
If most of the RBCs are chewed up in the spleen, do you think splenectomy is often helpful in the management of this disease? YES
G6PD converts glucose-6-phosphate into 6-phosphoglucono-Ī“-lactone and is the rate-limiting enzyme of the pentose phosphate pathway.
What are Heinz bodies? (denatured Hgb) Does G6PD deficiency put RBCs at more risk to oxidative DAMAGE? Ans: YES Is that why it is a hemolytic anemia? YES
Heinz bodies, precipitated hemoglobin are seen quite well on a methylene blue stain.
Heinz bodies are seen with alpha-thalasemia, NADPH deficiency, and liver disease too.
Is sickling more likely in oxygenated blood or NON-oxygenated blood? NON (i.e., REDUCED HGB)
Is sickle cell anemia the mother of all hemoglobinopathies? YES
What is the normal weight of a spleen? 150 gms
At first the spleen may be enlarged (left) because of HYPERPLENISM due to hemolysis, later it may infarct itself due to small vessel occlussive disease and be quite small (right), perhaps only 1/10 its normal size. What is a NORMAL spleen weight? 150 gm, same as kidney, 1/10th liver.
Note the āspiculatedā or āspikedā appearance of the outer table of the skull due to extreme erythroid hyperplasia! How is this different from a myeloma skull?
H= High affinity
Why is HIGH AFFINITY bad? Sucks in the O2 very readily, but wonāt give it up to the tissues!
NOT all hydrops fetalis is RH antigen related, is it?
Phosphatidylinositol N-acetylglucosaminyltransferase subunit AĀ is an enzymeĀ that in humans is encoded by theĀ PIGA gene.
PIGA makes GPI, defective PIGA makes defective or inadequate GPI. Why does the term hemoglobinuria imply hemolysis? What does āparoxysmalā meanā Ans: Sudden, UN-controllable, like a seizure
IHA was often called AHA, but AHA is a bad term because not all are autoimmune, but caused by drugs.
What is the difference between an āagglutininā and a āhemolysinā? Ans: ā-lysisā implies complement fixation.
The most common drugs to cause warm agglutinins are anti-microbials (e.g., cefotetan, ceftriaxone and piperacillin).
The Coombs is a routine test used in the workup of just about ALL kinds of hemolytic anemias
HUS often follows an E. Coli enteric infection in kids, and is a associated with a wide variety of disorders in adults, most closely linked to TTP.
Anemias of diminished erythropoesis.
Megalo
Fe def
Aplastic
Megaloblasts on top, macrocytes on bottom. What is the difference between a megaloblast and a macrocyte? What is the difference between a megaloblast and an erythroblast? Do the arrows point to macrocytes, i.e., RBCs with a high MCV. Why is it silly to say a single RBC has a high MCV?
This is the HARD way to remember megaloblastic anemias
This is the EASY way!
Now lets go back to the previous slide and it will all make sense!
But are all macrocytic anemias megaloblastic? Hell NO!
Liver diseases, hypothyroidism, hemolytic anemias can frequently show HIGH MCV, but NO megaloblasts in the marrow!
Why do neurologists carry tuning forks in their bags?
Why jaundice if PA is an anemia of impaired production rather than increased destruction? ANS: I donāt know!
What senses do the dorsolateral tracts carry? Pain, Temperature, Pressure, VIBRATION
Is iron deficiency anemia the mother of all anemias? YES
A great diagram of the iron cycle. Know what heme, transferrin, ferritin, and hemosiderin are in the iron cycle.
Is serum FE a horrible test of iron deficiency anemia? YES
Is a serum FERRITIN a GREAT test for iron deficiency anemia? YES!
Relate hypochromia, microcytosis, anisocytosis to the Wintrobe indices: Ans: MCHC, MCV, RDW, respectively
Golden brown refractile pigment on H&E is HEMOSIDERIN when it stains BLUE by the Prussian Blue method!
Any marrow that has stuff staining with Prussian Blue, is NOT an iron deficiency!
Most are hypochromic (low MCHC), and microcytic (low MCV) like Fe deficiency anemias but have NORMAL iron stores (i.e., hemosiderin).
Fanconi syndrome and Fanconi anemia are two completely different disorders, but named after the same guy, even though the āsyndromeā was NOT described by him. Fanconiās anemia is characterized byĀ short stature, skeletal anomalies, increased incidence of solid tumors and leukemias, bone marrow failure (aplastic anemia), and cellular sensitivity to DNA damaging agents such asĀ mitomycin C.
If you understand the cell differentiation concept, why would an aplastic anemia be less likely to involve lymphocytes?
The NORMAL adult RED bone marrow in the axial skeleton should be about 50% cells and 50% fat. What is this?
Perhaps around 10:90?
What would you think if the few cells you see here were primarily lymphocytes?
Does this sound like the usual suspects again?
How about radiation? Sure, if enough axial skeleton is zapped!
What are ādacryo-ācytes?
Wouldnāt marrow crowding by tumor cells or leukemia cells ALSO be considered DECREASED RBC production?
What do you think the most serious consequence might be for a person with increased RBCs and platelets?
Doesnāt this really boil down to TWO things? 1) Reduced platelet function/numbers, and, 2) everything else?
Normal platelets, but DAMAGED vessel walls, the so-called āangiopathicā thrombocytopenias.
At what platelet count level does SPONTANEOUS bleeding generally occur? Ans: ~20K Platelets normally 150K-300K. This is one ānormal rangeā you should memorize.
Note the last three items are ALL in the same category. Are platelets low in a āconsumptionā coagulopathy? Answer: Yes!
What are the āconsumableā clotting factors, classically? Answer: Platelets, fibrinogen, V, VIII
At what platelet count level does SPONTANEOUS bleeding generally occur? Ans: 20K Platelets normally 150K-300K
Any thrombocytopenia of increased destruction should have INCREASED megakaryocytes in the marrow! JUST LIKE a hemolytic anemia has an erythroid HYPER-plasia, same principle! Does this follow the pattern of a classic āautoimmuneā disease? Yes!
Remember MANY autoimmune diseases are triggered off by previous infections!
Platelet numbers may be normal but do not function well.
Hypercoagulability is anything which accelerates the cascade (common), or inhibits its inhibitors (rare).
By the way, von Willebrand patients are ALWAYS on the step-1 exam.
Because von Willebrand is so closely linked to Factor VIII, it has also been called āpseudoā-hemophilia, but so have many other clotting disorders, so avoid using this term.
Hypercoagulability is anything which accelerates the cascade (common), or inhibits its inhibitors (rare).
For all practical purposes, the same as Hemophilia A. How to differentiate? Factor assays! Note the AMAZING similarities between Hemophilia A and B
What is a āconsumptiveā coagulopathy? Ans: the platelets and many clotting factors are āconsumedā, i.e., used up!
Would you feel confident taking a patient to surgery if all these tests were normal, especially the first four? Answer: YES
Lets familiarize ourselves with all these abnormal RBC critters.