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Hematology Flashcards

1
Q

What is the definition of anemia?

A

A reduction in RBC number or in hgb concentration to a level that is more than two standard deviations below the mean

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2
Q

The Hgb is ______ at birth and reaches the physiologic lowest point between _ and _ months of age in the term infant (between _ and _ months in the preterm infant)

A

The Hgb is high at birth and reaches the physiologic lowest point between 3 and 4 months of age in the term infant (between 1 and 2 months in the preterm infant)

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3
Q

What is a major constitutent of Hgb during fetal and early postnatal life? When does it disappear?

A

Fetal hemoglobin (Hgb F); Disappears by 6-9 months of age

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4
Q

Classificaiton of anemia is based on what two parameters?

A

Mean corpuscular volume

Morphologic appearance of the RBC (size, color, shape)

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5
Q

What is the meaning of microcytic, hypochromic anemia?

A

Small, pale RBCs; low MCV

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6
Q

Why is the reticulocyte count helpful?

A

Reticulocyte count reflects the number of immature RBCs in circulation; Low reticulocyte counts indicate bone marrow failure or diminished hematopoiesis

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7
Q

What are the two most common causes of microcytic hypochromic anemias during childhood?

A

Iron deficiency anemia and ß-thalassemia trait

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8
Q

What causes the majority of iron deficiency anemia?

A

Inadequate iron intake

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9
Q

In what two age groups is nutritional iron deficiency most common? Why?

A

9-24 months of age: owing to inadequate intake and inadequate iron stores

Adolescent girls: because of poor diet, rapid growth, and loss of iron in menstrual blood

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10
Q

What are some clinical features of moderate anemia?

A
  • Weakness and fatigue
  • Decreased exercise tolerance
  • Irritability
  • Tachycardia
  • Tachypnea
  • Anorexia
  • Systolic heart murumur
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11
Q

What types of occult blood loss can lead to iron deficiency anemia?

A

Secondary to polyps, Meckel’s diverticulum, IBD, PUD, and early digestion of whole cow’s milk (iron-poor) beore age 1

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12
Q

Describe the mechanism leading to increased tranferrin in iron deficiency anema?

A

Iron stores disappear first leading to low serum ferritin; As serum iron decreases iron binding capacity increases manifested as increased transferrin and decreased transferrin saturation

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13
Q

Why is ferritin not always a reliable marker of iron deficiency anemia?

A

Because ferritin is also an acute-phase reactant, it may be increased in infection, disease states, and stress

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14
Q

In management of iron deficiency anemia, iron is given with ______ to enhance intestinal absorption

A

Vitamin C (orange juice)

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15
Q

What is the major Hgb in RBCs? What is it made up of?

A

Hemoglobin A1; A tetramer of two α chains and two ß chians

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16
Q

α-thalassemia results from…

ß-thalassemia results from…

A

Defective α-globin chain synthesis

Defective ß-globin chain synthesis

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17
Q

Why do thalessemias lead to increased size of bones in the face and skull?

A

Both types of thalassemia result in hemolysis that elads to increased bone marrow activity; as marrow activity increases, the marrow spaces enlarge, increasing the size of bones

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18
Q

What are the four disease states of α-thalassemia?

A
  • Silent carrier: only one α-globin gene is deleted
  • α-thalasssemia minor: Two α-globin genes are deleted; patients have mild anemia
  • Hgb H disease (Bart’s): Three α-globin genes are deleted and patients have severe anemia at birth with an an elevated Hgb Bart’s
  • Fetal hydrops: Four α-globin genes are deleted; infant dies in utero
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19
Q

What is ß-thalassemia major?

A

May be caused by either total absence of the ß-globin chains or deficient ß-globin chain production

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20
Q

α-thalassemia is most common in…

ß-thalassemia is most common in

A

α-thalassemia: Southeast Asians

ß-thalassemia: Mediterranean background

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21
Q

What are the clinical features of ß-thalassemia?

A
  • Hemolytic anemia beginning in infancy
  • Hepatosplenomegaly
  • Bone marrow hyperplasia (thalassemia facies)
  • Delayed growth and puberty may be present
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22
Q

What are the laboratory findings of ß-thalassemia?

A
  • Severe hypochromia and microcytosis
  • Target cells and poikilocytes
  • Elevated unconjugated bilirubin, serum iron, and LDH
  • Low or absent Hgb A and elevated Hgb F
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23
Q

How does ß-thalassemia lead to hemochromatosis? How can this be delayed?

A

Hemochromatosis is caused by increased iron absorption from the intestine and from iron transfused in transfused RBCs; Chelation of iron with deferoxamine promotes iron excretion and may help delay hemochromatosis

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24
Q

How do you treat ß-thalassemia minor?

What misdiagnosis can lead to harmful treatment of ß-thalassemia minor?

A

No treatment is required

Iron deficiency anemia (may be treated inappropriately with iron when iron level in ß-thalassemia minor is normal or elevated)

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25
Q

What leads to ring sideroblasts in sideroblastic anemia?

A

Ring sideroblasts result from the accumulation of iron in the mitochondria of RBC precursors

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26
Q

What aside from iron deficiency anemia, thalassemia and sideroblastic anemia can cause microcytic hypochromic anemia?

A

Lead toxicity and anemia of chronic disease

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27
Q

Macrocytic (megaloblastic) anemias are characterized by MCV > __

What are the two major causes in children?

A

95

Folic acid and Vitamin B12 deficiencies

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28
Q

What can lead to folic acid deficiency?

A
  • Diet lacking uncooked fresh fruits and vegetables
  • Exclusive feedings with goat’s milk
  • Decreased intestinal absorption due to celiac disease, enteritis, chron’s disease…
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29
Q

What medications can lead to folic acid deficiency?

A

Anticonvulsants and oral contraceptives

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30
Q

To be absorbed, dietary vitamin B12 must first combine with _______ secreted by _____ _______ cells; Absorption occurs in the _______ ______

A

To be absorbed, dietary vitamin B12 must first combine with glycoprotein (intrinsic factor) secreted by gastric parietal cells; Absorption occurs in the terminal ileum

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31
Q

What is the management of folic acid deficiency?

What is the management of vitamin B12 deficiency?

A

Folic acid: Dietary folic acid

B12: Monthly intramuscular vitamin B12 injections

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32
Q

What are some common causes of normocytic, normochromic anemias?

A

Hemolytic anemias, red cell aplasias, and sickle cell anemia

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33
Q

How are normocytic, normochromic anemias differentiated (name the lab and the significance of the lab values)?

A

Reticulocyte count

  • Low reticuloyte count: Reflects bone marrow suppression or failure and is consistent with red cell aplsias, pancytopenia, and malignancy
  • High reticulocyte count: reflects bone marrow production of RBCs as seen in hemolytic anemias and sickle cell anemia
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34
Q

What are the intrinsic hemolytic anemias that cause normocytic normochromic anemia?

A
  • Hereditary spherocytosis
  • Hereditary eliptocytosis
  • Glycolytic enzyme defects
    • Pyruvate kinase deficiency
    • Glucose-6-phosphate dehydrogenase deficiency
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35
Q

WHat is the most common inherited abnormality of the RBC membrane?

A

Hereditary spherocytosis

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36
Q

What protein is abnormal in hereditary spherocytosis? What is the inheritance patterns?

A

Abnormality of the structural RBC membrane protein spectrin

Usually autosomal dominant

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37
Q

What are the signs and symptoms of hereditary spherocytosis?

A
  • Splenomegaly by 2-3 years of age
  • Pigmentary gallstones
  • Aplastic crises (associated with parvovirus infection)
  • Jaundice and anemia
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38
Q

What studies can be used to diagnose hereditary spherocytosis?

A

Blood smear and osmotic fragility studies (spherocytes are more fragile)

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39
Q

What “cures” hereditary spherocytosis?

Why is this procedure delayed until after 5 years of age?

A

Splenectomy

Delayed to decreased the incidence of invasive disease caused by encapsulated bacteria

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40
Q

Hereditary elliptocytosis is autosomal _______ defect in the structure of _______

A

dominant; spectrin

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41
Q

What are the symptoms of patients with hereditary elliptocytosis?

A

Majority of patients are asymptomatic

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42
Q

Pyruvate kinase deficiency is an autosomal _______ disorder

A

recessive

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43
Q

What becomes depleted in PK deficiency? What is there decreased production of?

A

ATP depletion

Decreased production of PK isoenzyme

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44
Q

What is seen on blood smear of patients with Pyruvate kinase (PK) deficiency?

A

Polychromatic RBCs

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45
Q

What is the management for pyruvate kinase deficiency?

A

Transfusions and splenectomy for severe disease

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46
Q

What is the msot common RBC enzymatic defect?

A

Glucose-6-phosphate dehydrogenase deficiency

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47
Q

What is the pathosphysiology of G6PD deficiency and what triggers its symptoms?

A

G6PD enzyme is critical for protecting the RBC from oxidative stress; deficiency results in RBC damage when RBC exposed to oxidants

Triggers: Infection, Fava beans, sulfa drugs

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48
Q

_______ is not beneficial in G6PD deficiency

A

splenectomy

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49
Q

What are some extrinsic causes of hemolytic anemia?

A
  • Autoimmune hemolytic anemia
  • Alloimmune hemolytic anemia
  • Microangiopathic hemolytic anemia
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50
Q

What is autoimmune hemolytic anemia (AIHA)?

A

Occurs when antibodies are misdirected against the RBCs

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51
Q

What are the two types of AIHA?

A
  • Primary: Generally idiopathic in which no underlying disease is identified; viral infections and drugs may be causal
  • Secondary: associated with udnerlying disease process, such as lymphoma, SLE, or immunodeficiency disease
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52
Q

What are the clinical features of fulminant acute type AIHA? In what population does this occur?

A

Preceded by respiratory infection; features include acute onset of pallor, jaundice, hemoglobinuria, and splenomegaly

Occurs in infants and young children; complete recovery is expected

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53
Q

What are the laboratory findings in AIHA?

A

Severe anemia, spherocytes on blood smear, prominent reticulocytosis, and leukocytosis; Direct coombs test is positive

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54
Q

What is the management of AIHA?

A
  • Transfusions may provide transient benefit
  • Corticosteroids are used for severe anemia
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55
Q

Alloimmune hemolytic commonly involves newborn __ and ___ hemolytic diseases

A

Rh and ABO

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56
Q

When does Rh disease occur?

A

Rh hemolytic disese occurs when the mother (who has no Rh antigen) produces antibodies to the Rh antigen on her fetus’s RBCs; In subsequent pregnancies antibodies pass from the mother to the fetus causing hemolysis and hydrops fetalis

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57
Q

In Rh hemolytic disease, what test is strongly positive?

A

Direct Coombs

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58
Q

In ABO hemolytic disease, what are the results and strength of a direct coombs test?

A

Weakly positive

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59
Q

What is microangiopathic hemolytic anemia?

A

This form of anemia results from mechanical damage to RBCs caused by passage through an injured vascular endothelium

60
Q

What are some causes of microangiopathic hemolytic anemia?

A

Hypertension, hemolytic uremic syndrome, artificial heart valves, a giant hemangioma, and DIC

61
Q

What are the laboratory findings in microhangiopathic hemolytic anemia?

A

Studies show RBC fragmentation seen as “burr/helmet” cells, “target” cells, and irregularly shaped cells on blood smear, and thrombocytpenia

62
Q

What is the genetic cause of Sickle cell (SS) disease?

A

SS disease is caused by a single amino acid substitution of valine for gluamic acid on position 6 of the ß-globin chain of Hgb

63
Q

What effect on the RBC occurs with the mutation in SS disease?

A

Mutation results in polymerization of Hgb within the RBC membrane when the RBC is exposed to low oxygen or acidosis

64
Q

What is the difference between SS disease and SS trait?

A

SS disease: result of having 2 genes for Hgb S

SS trait: result of having only one gene for Hgb S; patients are usually asymptomatic without anemia

65
Q

How is SS disease diagnosed?

A

Usually diagnosed at brth through state newborn screening programs; Hgb Electrophoresis is a highly sensitive and specific test

66
Q

When are there clinical features of SS disease?

A

Not until after Hgb F declines (protective until 6 months of age)

67
Q

What types of crieses occur in SS disease?

A
  • Vasoocclusive crisis
  • Painful bone crisis
  • Acute abdominal crisis (sickling in mesenteric artery)
  • Stroke
  • Priapism
  • Acute chest syndrome (pulmonary infiltrate)
  • Sequestration crisis (accumulation of blood in spleen)
  • Aplastic crisis (parvovirus B19 or other infection)
  • Hyperhemolytic crisis
68
Q

How is a painful bone crisis managed?

A
  • Pain control
  • IV fluids at 1.5-2x maintenance
  • Incentive spirometry to decrease risk of Acute chest syndrome
  • May respond to partial exchange transfusion
69
Q

Which crises is treated with splenectomy?

Which are treated with supportive care and transfusion of RBCs?

A

Splenectomy: Sequestration crisis

Supportive care + RBCs: Aplastic crisis and hyperhemolytic crisis (rapid hemolysis)

70
Q

What is the leading cause of death from SS disease?

A

Infection

71
Q

What type of bacteria are patients with SS at risk for? Why?

A

Infection is a result of decreased splenic function so patients are at risk for infection with encapsulated bacteria (Hib, Strep pneumo, Salmonella, N. meningitidis)

72
Q

What other disease associated with SS disease may mimic a painful bone crisis? What is the most common cause?

A

Osteomyelitis, most commonly caused by salmonella (although S. Aureus may also cause osteomylitis)

73
Q

What is seen on blood smear in SS disease?

A

Sickled cells, target cells, Howell-Jolly bodies

74
Q

What increases Hgb F and has been shown to decrease vasoocclusive crises in SS disease?

A

Hydroxyurea

75
Q

What is started in SS disease patients within the first few months of life and why?

A

Daily oral penicillin prophylaxis to decrease the risk of S. pneumoniae infection

76
Q

What follow up is recommended beginning at 2 years of age for SS disease patients and why?

A

Serial transcranial Doppler ultrasound or magnetic resonance angiography to identify patients at risk for stroke

77
Q

What are red blood cell aplasias?

A

A group of congenital or acquired blood disorders characterized by anemia, reticulocytopenia, and a paucity of RBC precursors in the bone marrow

78
Q

What are the three most common red blood cell aplasias?

A
  • Congenital hypoplastic anemia (Diamond-Blackfan anemia)
  • Transient erythroblastopenia of childhood
  • Parvovirus B19 associated red cell aplasia
79
Q

Name the RBC aplasia:

Anemia within the first year of life, rapid onset

One fourth to one third have physical findings: craniofacial, renal, cardiac anomalies

Short stature; triphalangeal thumbs

A

Diamond Blackfan anemia

80
Q

What is Fanconi anemia? What is the inheritance pattern?

A

Congenital aplastic anemia; Autosomal recessive

81
Q

When is the onset of bone marrow failure in fanconi anemia? How does it present?

A

Mean age of 7 years; typical presentation is with ecchymosis and petechiae

82
Q

What are the skeletal abnormalities associated with Fanconi anemia?

A

Short stature in almost all patients with the absence of hypoplasia or the thumb and radius

83
Q

What laboratory values are seen in Fanconi anemia?

A
  • Pancytopenia
  • RBC macrocytosis
  • Low reticulocyte count
  • Elevated Hgb F
  • Bone marrow hypocellularity
84
Q

What is the management for Fanconi anemia?

A

Treatment includes transfusions of RBCs and platelets as needed, and bone marrow transplant from an HLA-compatible donor

85
Q

What is polycythemia?

A

An increase in RBCs relative to total blood volume or hematocrit > 60%

86
Q

What is polycythemia vera?

A

A malignancy involving the RBC precursor that occurs during childhood

87
Q

What is the most common cause of appropriate polycythemia in childhood? What can cause Inappropriate polycythemia?

A

Appropriate: Hypoxemia as a result of cyanotic congenital heart disease

Inappropriate: Benign and malignant tumors of the kidney, cerebellum, ovary, liver, and adrenal gland; excess hormone production and kidney abnormalities

88
Q

What is the management for polycythemia?

A

Treatment of underlying cause; phlebotomy is also used to keep Hct < 60%

89
Q

Possible complications of polycythemia are…

A

Thrombosis and bleeding

90
Q

The function of what three elements are required for hemostasis?

A

Blood vessels, platelets, and soluble cloting factors

91
Q

What clinical features suggest abnormal hemostasis in children?

A
  • Cutaneous bleeding (ecchymoses)
  • Spontaneous epistaxis
  • Prolonged bleeding after simple surgical procedures
  • Recurrent hemarthroses
  • Deep venous thrombosis
92
Q

What are the diagnostic studies for evaluation of clotting abnormalities?

A
  • CBC
  • Platelet count
  • Blood smear
  • aPTT and PT
  • Platelet function assay (less common)
93
Q

What are two inherited disorders involving factor VIII of the clotting cascade?

A

Hemophilia A and von Willebrand’s disease

94
Q

What is the difference between hemophilia A and von Wilebrand’s disease?

A

Hemophilia A: Defect in factor VIII procoagulant activity; platelet function is normal

von Willebrand’s disease: Factor VIII procoagulant activity is variable but platelet function is defective because of a decrease or defect in vW factor which is necessary for platelet adhesion to blood vessel walls

95
Q

What is the inheritance pattern of hemophilia A?

A

X-linked

96
Q

What are the hallmark clinical features of Hemophila A? What are the features of severe, moderate, and mild forms of the disease?

A
  • Hallmarks: Hemarthroses and deep soft tissue bleeding
  • Severe: spontaneous bleeding
  • Moderate: Bleeding only with trauma
  • Mild: Bleeding only after surgery or major trauma
97
Q

What is the most dreaded complication of hemophila A?

A

CNS bleeding (usually the result of head trauma)

98
Q

What lab findings are seen in hemophilia A?

A
  • Prolonged aPTT
  • Normal PT, bleeding time, platelet count, and platelet function assay
  • Low factor VIII protein activity
99
Q

What is the management for hemophilia A?

A

Treatment includes prevention of trauma and replacement of factor VIII

Desmopressin acetate (DDAVP) may cause the release of stored factor VIII from the patients

100
Q

What is the most common hereditary bleeding disorder?

What is it’s inheritance pattern?

A

von Willebrand’s disease

Autosomal dominant

101
Q

What are the 3 categories of von Wilebrand’s disease?

A
  • Type I (classic type): Mild quantitative deficiencies of vWf and factor VIII protein - Most common form
  • Type II: Qualitative abnormalitiy in vWf
  • Type III: Absence of vWf; the most severe type
102
Q

What are the clinical features of von Wilebrand’s disease?

A
  • Most patients have mild to moderate bleeding involving mucocutaneous surfaces
  • Epistaxis, menorrhagia, bruising, and bleeding after dental extraction or tonsillectomy
  • Hemarthroses are unusual
103
Q

How is von Willebrand’s disease diagnosed?

A
  • Prolonged bleeding time and aPTT may be present but not always
  • Quantitative assay for vWf antigen and activity (ristocetin cofactor assay)
104
Q

What is the management for von Wilebrand’s disease?

A

DDAVP - most useful in type I disease and is sometimes effective in type II disease

Cryoprecitpitate (contains intact vWf) - used for serious bleeding, extensive surgeries, or for type III disease

105
Q

What is the management for hemophilia B (Christmas tree disease)?

A

Factor IX replacement

106
Q

What clotting factors require vitamin K?

A

Factors II, VII, IX, and X and proteins C and S

107
Q

What can lead to vitamin K deficiency?

A
  • Dietary deficiency if in early infancy
  • Pancreatic insufficiency
  • Biliary obstruction
  • Prolonged diarrhea
  • Medications
  • Hemorrhagic disease of the newborn
108
Q

What are some clinical manifestations of vitamin K deficiency?

A
  • Bruising
  • Oozing from skin puncture wounds
  • Bleeding into organs
109
Q

What is the management for vitamin K deficiency?

A
  • Administration of vitamin K
  • Intramuscular administration of vitamin K after birth prevents hemorrhagic disease of the newborn
  • FFP in severe disease
110
Q

What laboratory findings are seen in DIC and liver disease?

A
  • Prolonged PT and aPTT
  • Thrombocytopenia
  • Elevated fibrin degradation products
111
Q

What is DIC?

A

A group of laboratory and clinical features indicative of both accelerated fibrogenesis and fibrinolysis; the initiating event is clotting that leads to consumption of procoagulant factors and resultant hemorrhage

112
Q

What is the management for DIC?

A

Therapy includes treatment of the underlying cause and transfusions of fibrinogen, FFP, and platelets as needed (same for liver disease); Heparin may be useful if underlying defect cannot be corrected

113
Q

What is Henoch-Schonlein purpura?

A

An IgA-mediated vasculitis that present with palpable purpura on the lower extremities and buttocks, renal insufficiency, arthritis, and abdominal pain; platelet count normal

114
Q

Hereditary hemorrhagic telangiectasia is an autosomal ________ disorder characterized by….

A

dominant; locally dilated and tortuous veins and capillaries of the skin and mucous membranes

115
Q

What is deficient in scurvy?

A

Vitamin C

116
Q

What is thrombocytopenia?

A

Decreased number of platelets, generally < 100,000; most common cause of bleding

117
Q

What are some congenital disorders leading to decreased platelet function?

A
  • Wiskott-Aldrich syndrome
  • Thrombocytopenia-absent radius syndrome (TAR)
118
Q

What X-linked disorder is characterized by thrombocytopenia with unusually small platelets, eczema, and defects in T-and B-cell immunity?

A

Wiskott-Aldrich syndrome

119
Q

What is TAR (thrombocytopenia-absent radius) syndrome?

A

Autosomal recessive disorder characterized by thrombocytopenia and limb abnormalities

120
Q

What is the most common acquired platelet abnormality in childhood?

A

Immune thrombocytopenic purpura (ITP)

121
Q

What are the causes of ITP? Which is most common?

A

ITP may be viral, drug induced, or idiopathic (most common)

122
Q

What are the clinical features of ITP?

A

Illness typically occurs 1-4 weeks after a viral infection

Begins abruptly with cutaneous bleeding or mucous membrane bleeding

Internal bleeding into the brain, kidneys, or GI tract may occur but is rare

123
Q

What is seen on blood smear in ITP?

A

Few large “sticky” platelets

124
Q

In ITP, very low platelet counts (<20,000) or active bleeding warrant treatment with…

What is the second line agent?

A

IVIG or corticosteroids

Anti-D immunoglobulin is a second-line agent that may aslo be effective

125
Q

What percentage of ITP cases resolve spontaneously?

How long must ITP last before it is considered chronic ITP?

A

70-80% resolve spontaneously

Chronic ITP is diagnosed if ITP lasts > 6 months

126
Q

What is passive autoimmune thrombocytopenia?

A

Occurs when the mother has ITP, and antibodies against her own platelets cross the placenta and destroy the fetus’s platelets

127
Q

What is isoimmune thrombocytopenia?

A

Occurs when the mother produces antibodies against her fetus’s platelets as a result of sensitization to an antigen that her own platelets lack

128
Q

In Kasabach-Merrit syndrome, large __________ may sequester and destroy platelets

A

hemangiomas

129
Q

What congenital disorders cause qualitative platelet dysfunction? What are their inheritance patterns?

A

Glanzmann’s thrombasthenia and Bernard-Soulier syndrome

Both are autosomal recessive

130
Q

What is the difference between Glanzmann’s thrombasthenia and Bernard-Soulier syndrome?

A

GT: Diminished ability of platelets to aggregate and clot as a result of deficient adhesive glycoprotein IIb/IIIa on the platelet cell membrane

BS: Decreased platelet adhesion as a result of absence of platelet membrane glycoproteins

131
Q

What are the types of protein C deficiency?

A

Homozygous: No protein C activity and detection shortly after birth; Pulpura fulminans, a nonthrombocytopenic purpura is often the inital presentation

Heterozygous: Present later with deep venous or CNS thrombosis

132
Q

What is the treatment for protein C deficiency

A

Treatment may include heparin, FFP, and warfarin; Purified concentrates of protein C have been used

133
Q

What other inherited coagulation abnormalities present similarly to protein C deficiency?

A

Protein S, antithrombin III, and factor V Leiden deficiencies

134
Q

What are the absolute neutrophil counts for mild, moderate and severe neutropenia?

A
  • Mild: ANC of 1,000-1,500
  • Moderate: 500-1,000
  • Severe: ANC < 500
135
Q

Risk of ______ is directly related to ANC

A

infection

136
Q

What types of infections can result from severe neutropenia?

A

S. aureus and gram-negative bacteria (Klebsiella, Serratia, Escheria coli, and Pseudomonas) are typical organisms

137
Q

What is the most common cause of neutropenia during childhood?

A

Infections

138
Q

What is chronic benigin neutropenia of childhood (CBN)?

A

A common cause of neutropenia in children younger than 4 years of age; refers to a group of acquired and inherited disorders with noncyclic neutropenia as the only abnormality

139
Q

What is shown in lab studies of CBN?

A

Studies who low ANC with a normal or slightly low WBC; bone marrow demonstrates immature neutrophil precursors

140
Q

What is severe congenital agranulocytosis (Kostmann syndrome?)

A

An autosomal recessive disorder with frequent and life-threatening pyogenic bacterial infections beginning in infancy; ANC is usually < 300

141
Q

What are the clinical features of cyclic neutropenia?

A

Cyclic alterations in neutrophil counts results in regular episodes of neutropenia with resultant infections

142
Q

How is cyclic neutropenia diagnosed? How long are cycles?

A

Diagnosis is made by obtaining serial neutrophil counts during a 2-3 month period

Cycles last an average of 21 days in 70% of patients

143
Q

What genetic syndromes can cause neutropenia?

A
  • Chediak-Higashi syndrome - occulocutaneous albinism and blond or brown hair with silver streaks
  • Cartilage-hair hypoplasia syndrome - short stature, immunodeficiency, fine hair
144
Q

What is Schwachman-Diamond syndrome?

A

Characterized by exocrine pancreatic insufficiency with malabsorption and short stature caused by metaphyseal chondrodysplasia

145
Q

Describe autoimmune neutropenia and isoimmune neutropenia

A

Autoimmune: A disorder in which antineutrophil antibodies are produced in response to infection, drugs, SLE, and juvenile rheumatoid arthritis

Isoimmune: Passive transfer of antineutrophil antibodies from the mother to her fetus after maternal sensitization by antigens on the fetal neutrophils

Pediatrics (24 decks)

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