Part2 by xiaopangnv

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									Chicago Medical School
Review for shelf exam and
         USMLE
          Part 2

  Arthur S. Schneider, M.D.
  Kimiko Suzue, M.D., Ph.D.
  Department of Pathology
                Part 2

Nutritional Disorders
Vascular Disorders and Hypertension
Diseases of the Heart
Anemia
Neoplastic and Proliferative Disorders of
the Hematopoietic and Lymphoid Systems
Hemorrhagic Disorders
NUTRITIONAL
 DISORDERS
    A. Water Soluble Vitamin
         Deficiencies
   Thiamine (vitamin B1)
       Wernicke-Korsakoff syndrome
          combination of alcoholism and thiamine deficiency
          hemorrhages into mamillary bodies and other
           bilateral paramedial masses of gray matter such as
           thalamus and hypothalamus
          ophthalmoplegia, nystagmus, ataxia, and
           confusion
       cardiomyopathy
       peripheral neuropathy
    A. Water Soluble Vitamin
         Deficiencies
   Ascorbic acid (vitamin C)
       impaired hydroxylations of proline and lysine
          defective collagen fibrillogenesis
          defective osteoid matrix formation

       abnormal bleeding, impaired wound healing,
        and bony abnormalities
    A. Water Soluble Vitamin
         Deficiencies
   Cobalamin (vitamin B12)
       dietary deficiency extremely rare, limited to
        absolute vegetarians (not seen in other
        causes of malnutrition such as alcoholism)
   Niacin
       three D's of pellagra: dementia, dermatitis,
        and diarrhea
      B. Fat Soluble Vitamin
         Deficiencies and
          Malabsorption
   Malabsorption is one cause of fat soluble
    vitamin deficiency
        B. Fat Soluble Vitamin
           Deficiencies and
            Malabsorption
   Vitamin A
       night blindness
       conjunctival keratinization
   Vitamin D
       osteomalacia and rickets
       1--hydroxylase deficiency can cause
        decrease in 1,25 dihydroxycholecalciferol,
        impaired absorption of calcium, and increased
        PTH
        B. Fat Soluble Vitamin
           Deficiencies and
            Malabsorption
   Vitamin K
       hemorrhagic disease of newborn
       deficiency of factors II, VII, IX, and X
            C. Protein-Calorie
               Malnutrition
   Kwashiorkor
       edema due to protein deficiency and
        decreased oncotic pressure
       depigmented bands (streaking) in hair or skin
VASCULAR DISORDERS
 AND HYPERTENSION
          A. Atherosclerosis

   Vascular injury  recruitment of platelets
     secretion of platelet-derived growth
    factor  recruitment of smooth muscle
    cells and macrophages
   Aspirin interferes with platelet aggregation
    by inhibiting thromboxane synthesis by
    way of cyclooxygenase pathway of
    arachidonic acid metabolism
            A. Atherosclerosis
   Complications
       calcification or hemorrhage of plaques 
        thrombosis and vascular occlusion
       myocardial and cerebral infarcts, gangrene of
        lower extremities
       aneurysm formation, especially in abdominal
        aorta
       mural thrombus formation (can lead to left-
        sided emboli)
            A. Atherosclerosis

   Contents of atheromatous plaques
       cholesterol crystals, foam cells (modified
        macrophages)
       smooth muscle cells, collagen, clotting factor
        proteins such as fibrin
   Incidence inversely related to HDL
    cholesterol levels
   Smoking is a risk factor
                 B. Aneurysms
   Atherosclerotic aneurysm
       abdominal (descending) aorta most frequent
        site
   Aneurysm of aortic root
       rarely atherosclerotic
       most frequent cause today is cystic medial
        necrosis
       in past, most frequent cause was syphilis
          endarteritis of vasa vasorum
          tree-bark appearance
                B. Aneurysms

   Berry aneurysms
       occur at bifurcations of vessels, especially in
        circle of Willis
       develop at sites of congenital medial
        weakness
       subarachnoid hemorrhage
       can be associated with polycystic kidney
        disease
       no relation to atherosclerosis
              B. Aneurysms
   Dissecting aneurysm of aorta
       tearing chest pain radiating through to
        back
       widening of aortic shadow on X-ray
       ECG normal
       death by rupture into pericardial space 
        hemopericardium with cardiac tamponade
        (most frequent cause of death)
       related to hypertension and cystic medial
        necrosis
       no relation to atherosclerosis
       can be part of Marfan's syndrome
       C. Raynaud's Disease

   Vasospasm of vessels of fingers or toes,
    especially in young women
     D. Pulmonary Embolism
     (Pulmonary Infarction)
   Infarcts hemorrhagic, wedge-shaped,
    subpleural
   Result of deep venous thrombosis
   Can be due to septic emboli which will
    result in abscess formation
               E. Vasculitides

   Hypersensitivity (leukocytoclastic angiitis)
       small vessels with lesions of same age
       reactions to drugs or microorganisms may be
        the cause
       can involve any site, including skin, glomeruli,
        GI tract
       palpable purpura
             E. Vasculitides
   Hypersensitivity (leukocytoclastic
    angiitis) (cont.)
       Henoch-Schönlein purpura
         a form of hypersensitivity (leukocytoclastic)
          vasculitis
         may be poststreptococcal in origin

         most common in young children

         hemorrhagic palpable purpura over buttocks
          and lower extremities
         fever, arthralgias, gastrointestinal signs and
          symptoms
         mild glomerulonephritis with hematuria and red
          cell casts
                E. Vasculitides
   Giant cell arteritis (temporal arteritis)
       older age group
   Mucocutaneous lymph node syndrome
    (Kawasaki disease)
       young children
       hemorrhagic edema of conjunctivae and oral mucosa
       cervical lymphadenopathy
       coronary artery vasculitis with aneurysm formation
               E. Vasculitides

   Thromboangiitis obliterans (Buerger's
    disease)
       exacerbated by cigarette smoking
       young men
       painful ischemic disease of extremities
       involves both medium to small vessels
        (arteries and veins)
               E. Vasculitides

   Wegener's granulomatosis
       granulomatous lesions in lungs and paranasal
        sinuses
       necrotizing immune complex arteritis and
        glomerulonephritis
               F. Hypertension
   Malignant nephrosclerosis
       leads to clinical syndrome of malignant
        hypertension
            severe hypertension, papilledema, and renal
             manifestations
       more common in young men of African
        descent
       often fatal
       flea-bitten kidney covered with petechiae
       necrotizing (fibrinous necrosis),
        glomerulitis, and arteriolitis
       proliferative arteriolosclerosis
               F. Hypertension
   Causes of secondary hypertension
       renal disease
       unilateral fibromuscular dysplasia of renal
        artery (unilateral renal artery stenosis)
            renal ischemia
                 increased renin secretion in affected kidney
                 can cause renal atrophy (affected kidney smaller
                  than unaffected kidney)
                 not a cause of renal infarcts (renal infarcts usually
                  due to emboli from the heart)
             F. Hypertension

   Causes of secondary hypertension (cont.)
       diabetic glomerulosclerosis
       pheochromocytoma  increased VMA and
        metanephrine secretion
       hyperadrenocorticism (Cushing's syndrome,
        primary aldosteronism), pheochromocytoma,
        hyperthyroidism
       coarctation of aorta (upper extremities)
DISEASES OF THE HEART
            A. Heart Failure

   Left ventricular failure characterized by
    pulmonary edema
               A. Heart Failure
   Right ventricular failure
       most common cause is left ventricular failure
       peripheral edema, chronic passive congestion of liver
        (nutmeg liver), distended neck veins
       a cause of hydrothorax (can be caused by either left
        or right-sided failure)
       ankle edema, hepatomegaly, distended neck veins
       can cause chronic passive congestion of liver with
        nutmeg liver
       can be mimicked by constrictive pericarditis
            A. Heart Failure

   Amyloidosis can manifest as combined left
    and right-sided failure
B. Congenital Heart Disease
   Cause most frequently unknown
   Other causes: rubella, chromosome
    defects (e.g., coarctation of aorta with
    Turner's syndrome)
   Cyanosis from right-to-left shunts (or left-
    to-right shunts with reversal of flow)
       decreased pulmonary blood flow with right-to-
        left shunts
   Cyanosis from birth
       transposition of great vessels
       tetralogy of Fallot
B. Congenital Heart Disease

   Endocardial cushion defects
       include atrial and ventricular septal defects
        and atrioventricular valve deformities
       frequent association with Down's syndrome
        (trisomy 21)
   Atrial septal defect
       pressure and O2 saturation equalized between
        two atria
B. Congenital Heart Disease

   Transposition of great vessels
       survival depends upon shunt between left and
        right ventricles
   Tetralogy of Fallot
       pulmonary stenosis, ventricular septal defect,
        overriding aorta, right ventricular hypertrophy
       right-to-left shunting and early cyanosis
       can cluster in families: inheritance
        multifactorial
     C. Mitral Valve Prolapse

   Posterior leaflet predominant site with
    parachute deformity
   Midsystolic click
   Usually does not cause harm
   Can occur in Marfan's syndrome
                   D. Rubella

   Infection in mother can affect fetus and
    can cause rubella syndrome
       congenital heart disease, microcephaly,
        deafness, and growth retardation
   Frequent cause of patent ductus
    arteriosus
   IgM antibodies indicate recent primary
    infection (not reinfection)
    E. Rheumatic Fever and
    Rheumatic Heart Disease
   Acute rheumatic fever
       pancarditis (myocarditis, pericarditis,
        endocarditis), and transient mild migratory
        polyarthritis
       immune injury (group A beta-hemolytic
        streptococci)
       focal interstitial inflammation in myocardium
        (Aschoff bodies)
    E. Rheumatic Fever and
    Rheumatic Heart Disease
   Acute rheumatic fever (cont.)
       small nonfriable verrucae (beadlike
        vegetations) along margins of valves
       mitral and aortic valves predominant sites
       Sydenham's chorea
       erythema marginatum
       elevated antistreptolysin O (ASO) titer
       MacCallum's plaque in left atrium
    E. Rheumatic Fever and
    Rheumatic Heart Disease
   Rheumatic heart disease
       thickening and fusion of chordae tendineae
       fusion of valve cusps
       valves most commonly affected are mitral
        and aortic
       pulmonic (pulmonary) valve rarely involved
       mitral stenosis
          fish-mouth buttonhole deformity of mitral valve
          diastolic blood pressure higher in left atrium
           than in left ventricle
    F. Infective Endocarditis

   Vegetations contain microorganisms
   Can be source of septic emboli to brain
   Can cause focal glomerulonephritis (can
    be due to septic emboli or can be immune
    complex in type)
   Can cause rupture of chordae tendineae
   Right-sided lesions suggest IV drug use
    (etiology often staphylococcal)
    G. Marantic Endocarditis

   Wasting diseases such as end-stage
    carcinomatosis
   Emboli are not septic
            H. Myocarditis

   Biventricular heart failure in young
    persons without valvular, rheumatic, or
    congenital defects
   Inflammatory infiltrate
   Can be caused by coxsackievirus,
    Trypanosoma cruzi (Chagas' disease)
    I. Carcinoid Heart Disease

   Plaque-like areas of endocardial thickening
    of the valves and other endocardial
    surfaces
   Primarily involves right side of the heart
     J. Myocardial Infarction

   Necrosis is coagulation in type
   Rupture causes death by cardiac
    tamponade
   Elevation of enzymes (AST, CPK, LDH) due
    to altered membrane permeability of
    necrotic myocardial cells
   Likelihood of shock depends on size of
    lesion
    J. Myocardial Infarction

   Sequence of changes
       6 hours or so after onset: no morphologic
        changes
       at 24 hours: neutrophils apparent
       at 3-7 days
          phagocytosis of debris by macrophages
          fibrovascular (granulation tissue) response begins

       mature scar by 7th week
    J. Myocardial Infarction
   Cells involved in evolution include
    neutrophils, macrophages, fibroblasts;
    lymphocytes and plasma cells not
    involved
   Injured cells release enzymes into
    circulation:
       CK (CPK) early, next AST (SGOT), latest is
        LDH (with LDH-2:LDH-1 flip pattern, i.e.,
        LDH-1 greater than LDH-2)
       CK peaks in 1-2 days, persists about 3 days
       LDH peaks in 2-3 days, lasts 6-7 days
       normal values if blood drawn too soon
     J. Myocardial Infarction

   Complications
       arrhythmia
       heart failure
       cardiogenic shock
       ruptured papillary muscle
       rupture with tamponade
       mural thrombosis (possible source of left-
        sided emboli)
        K. Cardiomyopathies
   Myocardial disease not secondary to
    coronary artery disease, hypertension,
    valvular disease, or infection
   Heart failure unresponsive to digitalis
   Arrhythmias
   Dilated (congestive) cardiomyopathy
       four-chamber hypertrophy and dilation
          intractable cardiac failure, both left and right
          associations with alcoholism, prior myocarditis
        K. Cardiomyopathies
   Restrictive cardiomyopathy
       amyloidosis
   Hypertrophic cardiomyopathy
       thickening of all chamber walls, especially
        ventricular septum (asymmetric septal
        hypertrophy)
       microscopically demonstrates hypertrophy
        and disarray of myocardial fibers in a
        disorganized, haphazard pattern
       a cause of sudden death in young athletes
          L. Cor Pulmonale

   Right ventricular hypertrophy and/or
    dilation secondary to lung disease or
    primary disease of pulmonary vasculature
    such as primary pulmonary hypertension
   Frequently due to emphysema
                    M. Other

   Myxoma
       left atrium
       most frequently occurring primary cardiac
        tumor
ANEMIA
                   A. ANEMIA

   Can be manifest as weakness, dizziness,
    pallor
   Anemia of pregnancy
       increased plasma volume with hemodilution,
        not true anemia
        B. Anemia of Chronic
         Blood Loss and Iron
          Deficiency Anemia
   Iron deficiency
       low serum iron, high total iron binding
        capacity (TIBC), low ferritin, low MCH,
        MCHC, MCV, absent marrow iron (negative
        reaction to Prussian blue stain)
       chronic blood loss from GI tract such as in
        carcinoma of colon, hookworm disease,
        etc.
       breast-fed infants
       hypochromic microcytic anemia (can also
        occur in thalassemia and in anemia of
        chronic disease)
     C. Serum Iron and Total
      Iron- Binding Capacity
              (TIBC)
   Iron deficiency
       serum iron low, TIBC high
   Thalassemia
       serum iron high, TIBC normal
   Anemia of chronic disease
       serum iron low, TIBC low (or normal, just not high)
   Hereditary hemochromatosis
       serum iron high, TIBC low
    D. Pernicious Anemia and
       Other Megaloblastic
            Anemias
   Peripheral blood findings: anemia, oval
    macrocytes (increased MCV [over 100]),
    leukopenia with hypersegmented
    neutrophils, thrombocytopenia
   Bone marrow shows megaloblastic
    hyperplasia
   Neurologic changes indicate vitamin B12
    deficiency rather than folate deficiency
   Deficiency in conversion of deoxyuridine
    to deoxythymidine in DNA synthesis
D. Pernicious Anemia and
   Other Megaloblastic
        Anemias
   Pernicious anemia
       vitamin B12 deficiency due to lack of
        intrinsic factor
       older age group
       combined systems disease (subacute
        combined degeneration) of spinal cord
          hyperreflexia, loss of position and vibration
           sensations
          demyelination of posterior and lateral columns

       anti-intrinsic factor antibodies
    D. Pernicious Anemia and
       Other Megaloblastic
            Anemias
   Folate deficiency anemia
       dietary deficiency, malabsorption, pregnancy
       no neurologic disease (in contrast to vitamin
        B12 deficiency)
           E. Schilling Test

   Pernicious anemia: decreased urinary
    excretion of labeled vitamin B12 corrected
    by intrinsic factor
   Total gastrectomy: same as pernicious
    anemia
           E. Schilling Test

   Blind loop syndrome (overgrowth of
    intestinal microorganisms,) intestinal
    malabsorption, Diphyllobothrium latum
    infestation: low urinary excretion; no
    correction by intrinsic factor
   Deficient dietary intake (absolute
    vegetarians): normal urinary excretion
    with or without intrinsic factor
    F. General Characteristics
       of Hemolytic Anemia
   Decreased hemoglobin, hematocrit, and RBC
   Reticulocytosis (MCV moderately increased, 105
    or so)
   Increased serum unconjugated bilirubin with
    jaundice
   Increased urine urobilinogen
   Decreased serum haptoglobin
   Pigmented gallstones
     G. Haptoglobin and Free
          Hemoglobin
   Haptoglobin
       decreased to absent (i.e., used up) in
        hemolytic anemias
   Free hemoglobin
       following hemolytic transfusion reaction,
        serum free hemoglobin does not rise until
        haptoglobin is depleted
    H. Autoimmune Hemolytic
             Anemia
   Hemolytic anemia of recent onset
   Autoantibodies to red cells (positive direct
    Coombs test [direct antiglobulin test])
     I. Hemolytic Disease of
          the Newborn
    (Erythroblastosis Fetalis)
   Prevented by administration to mother of
    RhoGam (anti-D IgG) at time of prior
    deliveries or terminations of pregnancy
     I. Hemolytic Disease of
          the Newborn
    (Erythroblastosis Fetalis)
   Kernicterus is staining of neonatal basal
    ganglia due to high concentration of
    unconjugated bilirubin
       unconjugated bilirubin crosses immature
        blood-brain barrier
       yellow staining of basal ganglia, thalamus,
        and several other CNS structures
       can cause permanent neurologic damage
     I. Hemolytic Disease of
          the Newborn
    (Erythroblastosis Fetalis)
   Serologic incompatibilities between mother
    and fetus
       Rh: mother d, child D
       ABO: mother O, child A or B
              mother A, child B or AB
              mother B, child A or AB
J. Hereditary Spherocytosis

   Spherocytes
   Jaundice
   Increased mean corpuscular hemoglobin
    concentration (MCHC)
   Increased erythrocyte osmotic fragility
   Spectrin deficiency (secondary to a variety
    of membrane protein defects)
              K. Schistocytes

   Fragmented RBC indicative of traumatic
    damage to circulating RBC
    (microangiopathic hemolytic anemia)
   Associations
       disseminated intravascular coagulation
       thrombotic thrombocytopenic purpura
       hemolytic anemia secondary to aortic valvular
        prostheses
      L. Sickle Cell Anemia
   Point mutation: glutamate  valine;
    can be detected by Southern blot;
    abolition of restriction site for Mst II
   Small spleen in adults
    (autosplenectomy)
   Sickle cell preparation (in vitro sickling
    with sodium metabisulfite) positive in all
    S disorders (SS, SC, sickle cell
    thalassemia, etc.)
   Salmonella osteomyelitis
          M. Thalassemia
   Decreased synthesis of - or ß-globin
    chains of hemoglobin
   Heme synthesis is unaffected
   Hypochromia, microcytosis, target cells
   Increase in fetal hemoglobin (HbF)
   Increase in hemoglobin A2 in ß-
    thalassemia minor (trait); look for
    decreased MCV
   Hb H (ß4) or Hb Barts (gamma4) in -
    thalassemias
    N. Resistance to Malaria in
             Africans
   Absence of red cell surface antigen Duffy
    (Fy)
   G6PD deficiency
   Hemoglobin S
     O. Hypoplastic Anemias
     (Bone Marrow Failure)
   Anemia (with reticulocytopenia),
    leukopenia, thrombocytopenia
   A wide variety of causes, including aplastic
    anemia, leukemias, tumor invasion of
    bone marrow
   Can also can occur in hypothyroidism
        O. Hypoplastic Anemias
        (Bone Marrow Failure)
   Aplastic anemia manifest by pancytopenia
    with hypocellular marrow
       Can result from toxic chemicals or drugs, such
        as benzene, antibiotics (especially
        chloramphenicol), and other drugs such as
        chlorpromazine
     P. Glucose-6-Phosphate
     Dehydrogenase (G6PD)
            Deficiency
   Hemolysis precipitated by primaquine (an
    antimalarial agent), sulfonamides, and
    many other oxidant drugs, and by
    infection
   Intravascular hemolysis with
    hemoglobinemia and hemoglobinuria
   X-linked disorder affecting 10% of African-
    Americans
   Heinz bodies and bite cells may be seen
         Q. Anemia of Chronic
               Disease
   Low serum iron
   Low or normal total iron-binding capacity
    (TIBC)
       in contrast to iron deficiency where TIBC is
        high
   Normal to increased marrow iron
                    R. Other

   Splenomegaly
       agnogenic myeloid metaplasia and other
        myeloproliferative syndromes
       hereditary spherocytosis
       infectious mononucleosis
       thalassemia major
   Hemorrhage
       platelet count goes up
  NEOPLASTIC AND
  PROLIFERATIVE
 DISORDERS OF THE
HEMATOPOIETIC AND
LYMPHOID SYSTEMS
      A. Myeloproliferative
      Syndromes (Including
         Chronic Myeloid
           Leukemia)
   Common features: middle to older age
    group, hyperuricemia, splenomegaly,
    basophilia, and nucleated RBC in
    peripheral blood
        A. Myeloproliferative
        Syndromes (Including
           Chronic Myeloid
             Leukemia)
   Predominant defining characteristics of
    individual myeloproliferative diseases
       chronic myeloid leukemia: granulocytic
        precursors
       polycythemia vera: erythrocytosis
       essential thrombocythemia:
        megakaryocytosis and thrombocytosis
       agnogenic myeloid metaplasia: marrow
        fibrosis with sparing of megakaryocytes
         A. Myeloproliferative
         Syndromes (Including
            Chronic Myeloid
              Leukemia)
   Polycythemia vera (primary polycythemia)
       low erythropoietin
   Secondary polycythemia
       high erythropoietin
       causes include androgen therapy, high
        altitude, adult polycystic kidney disease
        A. Myeloproliferative
        Syndromes (Including
           Chronic Myeloid
             Leukemia)
   Agnogenic myeloid metaplasia
       teardrop-shaped erythrocytes
       diagnostic finding is fibrosis in bone
        marrow (myelofibrosis)
       megakaryocytosis
     A. Myeloproliferative
     Syndromes (Including
        Chronic Myeloid
          Leukemia)
   Chronic myeloid leukemia: leukocytosis,
    Philadelphia chromosome (in
    hematopoietic cell lineages but not in
    lymphoid cells)
     B. Leukemoid Reactions

   High WBC count with immature
    neutrophils usually secondary to infection
    or malignancy
     C. Acute Lymphoblastic
           Leukemia
   Highest incidence in young children
   Blast cells in peripheral blood and bone
    marrow
   Cells often positive for CALLA (CD10)
    antigen
   Most common malignancy of children
    D. Hodgkin's Disease and
         Non-Hodgkin's
          Lymphomas
   Can present with periaortic tumor mass
   Reed-Sternberg cells in HD: diagnosis
    made by biopsy
   Prognosis depends mainly on extent of
    disease (staging) and presence or absence
    of systemic manifestations
    D. Hodgkin's Disease and
         Non-Hodgkin's
          Lymphomas
   Burkitt's lymphoma
       Epstein-Barr virus
       8;14 translocation: c-myc  immunoglobulin
        heavy chain locus
     E. Chronic Lymphocytic
           Leukemia
   Leukocytosis due to increased number of
    mature lymphocytes (nuclei have coarse
    clumpy chromatin pattern)
   Cells express surface immunoglobulins
    (IgD and IgM)
   Older age group
   B cells
     E. Chronic Lymphocytic
           Leukemia
   Incurable (today's Rx)
   Hypogammaglobulinemia occurs early in
    disease
   Bone marrow failure (anemia,
    thrombocytopenia, granulocytopenia)
    occurs late in disease
    F. Multiple Myeloma and
       Other Plasma Cell
           Disorders
   Multiple myeloma
       neoplastic plasma cells in bone marrow smear
       painful bony lesions
       lytic bone lesions (punched-out lesions)
       hypercalcemia due to bone destruction
        (parathyroid hormone activity is normal)
       normal alkaline phosphatase, phosphorus,
        and parathyroid hormone
    F. Multiple Myeloma and
       Other Plasma Cell
           Disorders
   Multiple myeloma (cont.)
       monoclonal gammopathy manifest as
        narrow spike on protein electrophoresis
        and urinary light chains (Bence Jones
        protein)
       bone marrow failure (anemia, leukopenia,
        thrombocytopenia)
       rouleaux
       increased erythrocyte sedimentation rate
       renal failure
       older age group
       amyloidosis of glomeruli
 F. Multiple Myeloma and
Other Plasma Cell Disorders
   Waldenström's macroglobulinemia
       serum IgM monoclonal protein, plasmacytoid
        lymphocytes, urinary light chains
   Benign monoclonal gammopathy
    (monoclonal gammopathy of
    undetermined significance, MGUS)
       serum spike <3 gm/dl, no Bence Jones
        protein, no decrease in normal
        immunoglobulins
             G. Infectious
             Mononucleosis
   Caused by Epstein-Barr virus
   Lesions in liver and lymphoid tissue
   Fever, sore throat, lymphadenopathy, and
    hepatosplenomegaly
   Atypical lymphocytes
           G. Infectious
           Mononucleosis
   Heterophil agglutinins (antibodies to
    sheep red cells)
   Heterophil-negative infectious
    mononucleosis most often caused by
    cytomegalovirus
   Splenic rupture can occur (shock and
    abdominal pain are clinical indicators)
HEMORRHAGIC
 DISORDERS
     A. Primary Hemostatic
            Bleeding
   Failure of initial platelet plug formation
   Causes
       ascorbic acid (vitamin C) deficiency
            increased capillary fragility
       infection (meningococcus, rickettsiae)
       thrombocytopenia or functional platelet
        disorders such as Glanzmann's
        thrombasthenia, or defects in platelet
        adhesion such as von Willebrand's disease
     A. Primary Hemostatic
            Bleeding
   Clinical characteristics
       mucocutaneous bleeding with pinpoint
        cutaneous hemorrhages (petechiae),
        epistaxis, and oozing from gums
       prolonged bleeding time
   Thrombocytopenia
       can be manifest by petechiae, more
        numerous over lower extremities
       thrombocytopenic bleeding can be
        described as a rash
     A. Primary Hemostatic
            Bleeding
   Thrombocytopenia
       causes: disseminated intravascular
        coagulation (DIC), antiplatelet antibodies,
        bone marrow failure (leukemia,
        myelophthisis, etc.)
       idiopathic (immune) thrombocytopenic
        purpura (ITP)
          thrombocytopenia
          numerous megakaryocytes in bone marrow

          in children, can follow viral illness

          affected mothers can pass maternal
           autoantibodies to fetus
     A. Primary Hemostatic
            Bleeding
   Thrombocytopenia (continued)
       thrombotic thrombocytopenic purpura
        (TTP)
          thrombocytopenia
          microangiopathic hemolytic anemia

          changing neurologic signs

          hyaline microthrombi
B. Secondary Hemostatic
       Bleeding
   Faults in coagulation cascade
   Clinical characteristics
       more extensive bleeding than in primary
        hemostatic defects
            ecchymoses, hemarthroses
       abnormal clotting tests
            partial thromboplastin time
                 measures fibrinogen and all clotting factors except
                  factors VII and XIII
            prothrombin time
                 measures fibrinogen and factors II, V, VII, and X
B. Secondary Hemostatic
       Bleeding
   Classic hemophilia
       factor VIII deficiency
            X-linked inheritance
       prolonged activated partial thromboplastin
        time
            can be corrected by addition of normal plasma
             to test system
       prolonged whole blood coagulation time
       normal bleeding time, prothrombin time,
        thrombin time
B. Secondary Hemostatic
       Bleeding
   Christmas disease
       factor IX deficiency
       clinically indistinguisable from classic
        hemophilia
   Vitamin K deficiency
       hemorrhagic disease of newborn
       liver disease
       deficiency of factors II, VII, IX, and X
         C. Disseminated
    Intravascular Coagulation
              (DIC)
   Combination of thrombosis and
    hemorrhage
   Microangiopathic hemolytic anemia
    (fragmented red cells, schistocytes)
   Microthrombi in small vessels such as
    glomeruli
         C. Disseminated
    Intravascular Coagulation
              (DIC)
   Frequently due to obstetric complications
    such as abruptio placentae (premature
    separation of placenta), retained dead
    fetus, and amniotic fluid embolism
    (potentially fatal complication of
    childbearing)
   Also frequently due to cancer, trauma, or
    gram-negative sepsis
     C. Disseminated
Intravascular Coagulation
          (DIC)
   Laboratory abnormalities
       decreased platelet count  increased
        bleeding time
       decreased factors II, V, VIII, and
        fibrinogen  increased prothrombin time
        and increased activated partial
        thromboplastin time
       consumption of fibrinogen  low
        fibrinogen and increased fibrin-fibrinogen
        split degradation products
                   D. Other

   Function of factor XIII: cross-linkage of
    fibrin
   Von Willebrand’s disease
       combined primary and secondary hemostatic
        bleeding
       autosomal inheritance
       normal platelet count

								
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