Hematology Flashcards
Relationship between hemoglobin and age?
- High at birth
- lowest point at 2-3 months of age in term infant (1-2 months of age in preterm infants)
- Adult levels after puberty
Definition of anemia?
Reduction in red blood cells more than two standard deviations below the mean
When does fetal hemoglobin decline?
6-9 months of age
Most common blood disease during infancy? Age-related causes? Clinical features? Laboratory findings? Management?
Iron deficiency anemia
- 9-24 months of age - Inadequate intake/storage (Iron stores depleted by 6-9 months of age)
- Toddlers– Cows milk
- Adolescent girls – poor diet, growth, menstrual blood
- Any age: Occult blood loss – Meckel’s diverticulum, IBD, peptic also disease, early cows milk
Underweight, spoon shaped nails, diminished attention/ability to learn
Low ferritin, increased transferrin, decreased transferrin saturation
- 4-6 mg/kg/day iron given with vitamin C (Orange juice) to enhance absorption
- RBC transfusion if in congestive heart failure
Thalassemia – Pathophys of physical exam findings?
Increased bone marrow activity leads to increased marrow space results in increased size of bones face and skull
alpha-thalassemia – Ethnic group? Types?
Southeast Asians
- silent
- mild anemia
- Hemoglobin H disease – severe anemia with elevated hemoglobin Bart
- Only hemoglobin Barts – hydrous fetalis
Beta thalassemia major – ethnic group? Clinical features? Laboratory findings? Management? Complications?
Mediterranean
- Hepatosplenomegaly
- Bone marrow hyperplasia leading to frontal bossing, prominent cheekbones, skull deformities
- Hypochromia and Microcytosis with Target cells
- Elevated Bilirubin, serum iron, LDH
- Electrophoresis – absent hemoglobin A and elevated hemoglobin F
Lifelong transfusions, splenectomy, bone marrow transplant
Hemachromatosis from transfusions
Beta thalassemia minor – laboratory findings? Treatment?
- Hemoglobin levels 2 to 3 below norm
- Hypochromia with microcytosis, and target cells
No treatment
Causes of sideroblastic anemia?
Inherited
Isoniazid, alcohol, lead, chloramphenicol
Folic acid deficiency – causes in children? Clinical features? Diagnosis? Management?
- Diet without fruits/vegetables
- Exclusive feedings with goats milk
- Decreased absorption (celiac disease, enteritis, Crohn’s disease, anticonvulsants, OCP)
Failure to thrive, chronic diarrhea
High levels of homocysteine without increased methylmalonic acid
Dietary folic acid
B12 deficiency – causes and children? Clinical features? The diagnosis? Management?
- Inadequate dietary intake (Vegan diets)
- Juvenile pernicious anemia
- Malabsorption (Crohn’s disease)
- Smooth red tongue
- Neurologic – ataxia, hyporeflexia, positive Babinski responses
High homocystine and Methylmalonic acid
Monthly B12 injections
Child with normocytic anemia – causes of low reticulocyte count? High reticulocyte count?
Res cell aplasias, pancytopenia, malignancy
Hemolytic anemias, sickle cell
Most common inherited abnormality of red blood cell membrane? Inheritance? Mechanism? Clinical features? Lab findings? Management?
Hereditary spherocytosis; Ensemble dominant; defective spectrin
- Splenomegaly by three years of age
- Pigmented gallstones
- Aplastic crises with parvovirus infection
- Infants present with jaundice
- Elevated reticulocyte count
- hyperbilirubinemia
- spherocytes on smear
- abnormal osmotic fragility studies
Cured by splenectomy (usually done after five years of age)
Hereditary elliptocytosis – inheritance? Clinical findings? Treatment?
Autosomal dominant
- Most patients are asymptomatic
- Jaundice, splenomegaly, gallstones
Splenectomy only if patients have hemolysis
Pyruvate kinase deficiency – mechanism? Clinical features? Laboratory findings? Diagnosis? Management?
Decreased pyruvic kinases leading to ATP depletion and decreased red blood cell survival
Power, jaundice, splenomegaly – kernicterus in neonates.
Polychromatic red blood cells on smear
Most common red blood cell and somatic defect? Mechanism? Triggers? Clinical features? Laboratory findings? Diagnosis? Treatment?
G6PD deficiency – increased oxidative damage
Infection, fava beans, sulfa drugs, salicylates, antimalarials,
Jaundice, vomiting/diarrhea, fever
Bite cells and Heinz bodies on smear
Low G6PD in red blood cells
Transfusions
Fulminant versus prolonged autoimmune hemolytic anemia - course and prognosis? Laboratory findings? Management?
Occurs in children after respiratory infections (complete recovery expected) versus due to underlying cause (protracted course and high mortality)
Positive direct Coombs test
Corticosteroids
Alloimmune hemolytic anemia? Types?
Rh & ABO hemolytic diseases
Rh hemolytic disease? Test? Management?
Rh negative mother produces antibodies to Rh antigen in fetus. In subsequent pregnancies antibodies cause Mollasses in fetal red blood cells leading to kernicterus, anemia, hepatosplenomegaly, and hydrops fetalis
Strongly positive Coombs’ test
Phototherapy if mild jaundice, exchange transfusion it’s severe jaundice
ABO hemolytic disease? Test? Management?
O type mother produces antibodies to A/B blood group antigen causing hemolysis in fetus (can occur in the first pregnancy, unlike Rh disease)
Weekly positive direct Coombs’ test
Phototherapy for mild jaundice; exchange transfusion for severe jaundice
Sickle cell disease – mutation?
Valine for glutamic acid in sixth position of beta-globin chain
Findings in sickle cell trait patients? Symptoms?
Small percentage of hemoglobin S
- Asymptomatic without anemia unless exposed to severe hypoxemia
- During adolescence some patients have hematuria or are unable to concentrate urine
Most common type of crisis and sickle cell patients? Subtype? Duration? Management?
Painful bone crisis due to ischemia/infarction of bone
Subtype: acute dactylitis – swelling of digits
Last 3-7 days
- IV fluids at two times maintenance
- Incentive spirometry
- Pain control
- If unremitting pain – consider exchange transfusion (Regular transfusion may worsen crisis)
Patient with sickle cell who presents with dysarthria, hemiplegia? Treatment?
Stroke
- Same management as for bone crisis but with urgent exchange transfusion
- chronic transfusions program to prevent recurrence
Always consider SS disease in any patient presenting with?
Priapism
Acute chest syndrome? Causes? Treatment?
Pulmonary infiltrate associated with respiratory symptoms
Viral, bacterial, Sickling, fat embolism, fluid overload
- Careful hydration and pain management
- Cefuroxamine and azithromycin
- Incentive spirometry
- Early partial exchange transfusion if no rapid improvement
Sequestration crisis? Typical age? Physical exam findings? Management?
Rapid accumulation of blood and spleen liver
Less than six years of age
Abdominal distention/pain
SOB
Tachycardia
Transfusion, splenectomy
Leading cause of death in sickle-cell? Management of fever in any patient with sickle cell?
Infection by encapsulated bacteria
Cultures, CXR, parenteral antibiotics until infection ruled out
May mimic painful bone crisis? Most commonly caused by?
Osteomyelitis; salmonella
Lab findings in sickle cell anemia:
- Red blood cell lifespan
- Hemoglobin
- Reticulocyte count
- WBC count
- Platelet count
- Blood smear
- 10 to 50 days
- 6 to 9
- 5-15%
- 12,000 to 20,000
- Greater than 500,000
- Sickle cells, target cells, Howell-Jolly bodies
Preventative care for sickle cell?
- Hydroxyurea (increases hemoglobin F)
- Daily oral penicillin prophylaxis for first few months of life
- Daily folic acid
- Routine immunizations
- Transcranial Doppler ultrasound or MRA beginning at age 2
Long-term complications of sickle cell?
- Delayed growth/puberty
- Cardiomegaly, cor pulmonale
- Hemachromatosis
- Gallstones
- Poor wound healing
- Avascular necklaces
Causes of red blood cells aplasias in childhood?
- Parvovirus
- Congenital hypoplastic anemia (Diamond-Blackfan anemia)
- Transient erythroblastopenia of childhood
Fanconi anemia AKA? inheritance? Age of onset? Clinical features? Laboratory findings? Management?
Congenital aplastic anemia; autosomal recessive; seven years
- Skeletal – short stature, absence of thumb/radius
- Skin hyperpigmentation
- Renal abnormalities
Pancytopenia, RBC macrocytosis, low reticulocyte count, elevated hemoglobin F
Transfusions, bone marrow transplant, immunosuppressive therapy
Congenital hypoplastic anemia a.k.a.? Age of onset? Clinical features? Lab findings? Treatment?
Diamond-Blackfan anemia; first year of life
- Skeletal – short stature, triphalangeal thumbs
- Renal/cardiac abnormalities
Decreased hemoglobin, reticulocytes, platelet count, RBC precursors
Transfusions, corticosteroids, Bonow transplant
Transient erythroblastopenia of childhood – age of onset? clinical features? Laboratory findings? Treatment?
Slow onset beginning at one year
Decreased hemoglobin, reticulocytes, red blood cell precursors
Spontaneous recovery within seven weeks
Definition of polycythemia? Most common cause? Clinical signs? Complications?
Hematocrit >60
Cyanotic Congenital heart disease
Ruddy facial complexion with normal sized liver/spleen
Thrombosis, bleeding
- PTT in von Willebrand disease?
- Bleeding time in thrombocytopenia?
- Petechia seen in these four disorders?
- Prolonged
- Prolonged
- Thrombocytopenia, platelet function defect, vitamin K deficiency, DIC
Platelet factor 2 AKA? Factor 1?
Prothrombin; fibrinogen
Management of hemophilia? Mech?
DDAVP to release stored factor 8
Signs of von Willebrand disease? Management?
Epistaxes, menorrhagia, bruising, bleeding after dental extraction
- DDAVP to release von Willebrand factor from endothelial cells
- Cryoprecipitate
Causes of vitamin K deficiency?
- Pancreatic insufficiency, biliary obstruction
- Prolonged diarrhea
- Medications (of cephalosporins, rifampin, warfarin, isoniazid)
Congenital disorders with decreased platelet production (And other findings)?
Wiskott-Aldrich syndrome – Small platelets, eczema, defects in T/B cell immunity
Thrombocytopenic Absent-radius syndrome – No radius (but unlike Fanconi, thumb is present), ASD/tetralogy, renal disease
ITP – when to treat?
Platelet count less than 20,000 – IVIG, corticosteroids, anti-D immunoglobulin (if Rh positive)
Passive autoimmune thrombocytopenia versus Isoimmune thrombocytopenia?
ITP antibodies destroy fetus’ platelets. Mother HAS thrombocytopenia
Mother produces antibodies against fetus’ platelets. Mother does NOT have thrombocytopenia
Kasabach-Merritt Syndrome - pathophysiology? Characteristics?
Large hemangiomas sequester/destroy platelets
hemangioma, microangiopathic hemolytic anemia, thrombocytopenia
Glanzmann’s versus Bernard-Soulier syndrome
Decreased platelet aggregation (glycoprotein IIb/IIIa versus decreased platelet adhesion
Inherited hypercoagulabilities?
- Protein C/S deficiency
- Antithrombin III deficiency
- Factor five Leiden deficiency
Protein C deficiency – initially presents with (specific name)? Clinical features? And itching?
Purpura Fulminans (non-thrombocytopenic purpura)
Fever, shock, skin bleeding, thrombosis
Heparin, FFP, warfarin
Mild versus moderate versus severe neutropenia?
Absolute neutrophil count is: 1000-1500 versus 500-1000 versus <500
Common cause of neutropenia in children younger than four? Clinical features? Laboratory findings? Prognosis?
Chronic benign neutropenia of childhood
Increased incidence of mild infections (otitis media, sinusitis, pharyngitis, cellulitis)
- Low absolute neutrophil count
- immature neutrophil precursors in bone marrow
Resolve spontaneously
Kostmann Syndrome – a.k.a.? Absolute neutrophil count? Clinical features?
Severe congenital agranulocytosis; <300
Frequent pyogenic bacterial infections beginning in infancy
Cyclic neutropenia – Pathophysiology? clinical features? Diagnosis?
Cyclical alterations and nutrition counseling result in episodes of neutropenia with infections
Fever, oral ulcers, stomatitis
Serial neutrophil counts during 2 to 3 months.
Chediak-Higashi – clinical features? Histo?
- Albinism
- Blonde hair with silver streaks
- Infections
Blue-great granules in cytoplasm of neutrophils
Cartilage-hair hypoplasia syndrome – characterized by?
- Short stature
- Immunodeficiency/neutropenia
- Fine hair
Schwachman-Diamond syndrome – characterized by?
- Short stature due to metaphyseal chondrodysplasia
- Neutropenia
- Exocrine pancreatic insufficiency with Malabsorption
Metabolic diseases that can result in neutropenia?
Hyperglycemia, methylmalonic acidemia, Gaucher’s disease
