Hematology and oncology- Phatology Flashcards
Acanthocytes (“spur cells”)
Liver disease, abetalipoproteinemia (states of cholesterol dysregulation).
Acantho = spiny
Basophilic stippling
Sideroblastic anemias (eg, lead poisoning, myelodysplastic syndromes), thalassemias.
*Seen primarily in peripheral smear, vs ringed sideroblasts seen in bone marrow.
Dacrocytes (“teardrop cells”)
Bone marrow infiltration (eg, myelofibrosis), thalassemias.
RBC “sheds a tear” because it’s mechanically squeezed out of its home in the bone marrow.
Degmacytes (“bite cells”)
G6PD deficiency.
Echinocytes (“burr cells”)
End-stage renal disease, liver disease, pyruvate kinase
deficiency.
Elliptocytes
Hereditary elliptocytosis (espectrin), usually asymptomatic
Macro-ovalocytes
Megaloblastic anemia (also hypersegmented PMNs)
Ringed sideroblasts
Sideroblastic anemia. Excess iron in mitochondria.
Seen in bone marrow with special staining (Prussian blue),
Schistocytes
Microangiopathic hemolytic anemias, including DIC, TTP/HUS, HELLP syndrome, mechanical hemolysis
Sickle cells
Sickle cell anemia.
Spherocytes
Hereditary spherocytosis, drug- and infection-induced hemolytic anemia.
Small, spherical cells without central pallor.
Target cells
“HALT,”
HbC disease, Asplenia, Liver disease, Thalassemia.
Heinz bodies
Seen in G6PD deficiency.
Howell-Jolly bodies
Seen in patients with functional hyposplenia or asplenia.
Basophilic nuclear remnants found in RBCs
Anemias Algorithm
Pag. 406
Iron deficiency anemia
- Labs
- Symptoms
Labs: Low iron, HighTIBC, Low ferritin, High free erythrocyte protoporphyrin, High RDW. Microcytosis and hypochromasia (central pallor).
Symptoms: fatigue, conjunctival pallor, pica, spoon nails
(koilonychia). May manifest as glossitis, cheilosis.
α-thalassemia
- α-thalassemia minima
- α-thalassemia minor
(α α/α –). No anemia (silent carrier)
(α –/α –; trans) or (α α/– –; cis). Mild microcytic, hypochromic anemia
α-thalassemia
- Hemoglobin H disease (HbH); β4
- Hemoglobin Barts disease (Hb Barts); γ4
(– –/– α). Moderate to severe microcytic hypochromic anemia.
(– –/– –). Hydrops fetalis; incompatible with life
β-thalassemia
- β-thalassemia minor (heterozygote)
- HbS/β-thalassemia heterozygote
β chain is underproduced. Usually asymptomatic. Diagnosis confirmed by HbA2 (> 3.5%) on electrophoresis.
mild to moderate sickle cell disease depending on amount of β-globin production.
β-thalassemia
- β-thalassemia major (homozygote)
severe microcytic, hypochromic ,anemia with target cells and increased anisopoikilocytosis requiring blood transfusion (2° hemochromatosis).
skeletal deformities. “Chipmunk” facies. hepatosplenomegaly. risk of parvovirus B19–induced aplastic crisis.
HbF (α2γ2), HbA2 (α2δ2).
Lead poisoning
- Mechanism
- Clinical features
- Treatment
Lead inhibits ferrochelatase and ALA dehydratase.
“LEAD”
- Lead Lines on gingivae (Burton lines) and on metaphyses of long bones on x-ray.
- Encephalopathy and Erythrocyte basophilic stippling.
- Abdominal colic and sideroblastic Anemia.
- Drops—wrist and foot drop.
Dimercaprol and EDTA are 1st line of treatment. Succimer used for chelation for kids
Sideroblastic anemia
- Etiology
- Labs
- Treatment
Genetic (eg, X-linked defect in ALA synthase gene), acquired (myelodysplastic syndromes), and reversible (alcohol is most common).
High iron, normal/Low TIBC, High ferritin. Ringed sideroblasts. basophilic stippling.
Treatment: pyridoxine (B6, cofactor for ALA synthase).
Megaloblastic anemia
- Mechanism
- Cell morphology
- Etiology
Impaired DNA synthesis. delayed relative to maturation of cytoplasm.
RBC macrocytosis, hypersegmented neutrophils, glossitis.
- Folate deficiency, Vitamin B12 (cobalamin) deficiency, Orotic aciduria
Folate deficiency
- Etiology
- Labs
Causes: malnutrition, malabsorption, drugs (eg, methotrexate, trimethoprim, phenytoin), requirement (eg, hemolytic anemia, pregnancy).
High homocysteine, normal methylmalonic acid.
*No neurologic symptoms
Vitamin B12 (cobalamin) deficiency
Causes: pernicious anemia, malabsorption, gastrectomy, insufficient intake, Diphyllobothrium latum (fish tapeworm).
High homocysteine, Highmethylmalonic acid.
*Neurologic symptoms. Historically diagnosed with the Schilling test.
Orotic aciduria
- Phatogeny
- Diagnosis
Inability to convert orotic acid to UMP (de novo pyrimidine synthesis pathway) because of defect in UMP synthase. AR
Orotic acid in urine.
Orotic aciduria
- Clinical presentation
- Treatment
Presents in children as failure to thrive, developmental delay, and megaloblastic anemia refractory to folate
and B12.
Treatment: uridine monophosphate or uridine
triacetate to bypass mutated enzyme.
Diamond-Blackfan anemia
- Etiology
- Labs
- Clinical features
Rapid-onset anemia within 1st year of life due to intrinsic defect in erythroid progenitor cells.
High% HbF (but total Hb).
Short stature, craniofacial abnormalities, and upper extremity malformations (triphalangeal thumbs) in up to 50% of cases.
Intravascular hemolysis
- Findings
- Etiology
Low haptoglobin, schistocytes on blood smear. Characteristic hemoglobinuria, hemosiderinuria, and urobilinogen in urine.
Notable causes are mechanical hemolysis (eg, prosthetic valve), paroxysmal nocturnal hemoglobinuria,
microangiopathic hemolytic anemias.
Extravascular hemolysis
- Findings
Findings: macrophages in spleen clear RBCs. Spherocytes in peripheral smear, no hemoglobinuria/
hemosiderinuria. Can present with urobilinogen in urine
Anemia of chronic disease
- Etiophatogeny
- Labs
- RBC morphology
Inflammation, high hepcidin.
Low iron, Low TIBC, High ferritin.
Normocytic, but can become microcytic.
Aplastic anemia
- Etiologies
- Radiation and drugs (eg, benzene, chloramphenicol, alkylating agents, antimetabolites).
- Viral agents (EBV, HIV, hepatitis viruses)
- Fanconi anemia; also short stature, incidence of
tumors/leukemia, café-au-lait spots, thumb/radial defects. - Idiopathic (immune mediated, 1° stem cell defect); may follow acute hepatitis
Aplastic anemia
- Labs
- Morphology
Pancytopenia characterized by anemia, leukopenia, and thrombocytopenia.
Normal cell morphology, but hypocellular bone marrow with fatty infiltration
Hereditary spherocytosis
- Etiology
- Clinical features
- Labs
- Treatment
Defects RBC membrane (eg, ankyrin, band 3, protein 4.2, spectrin). AD
Splenomegaly, aplastic crisis (parvovirus B19 infection).
Labs: fragility in osmotic fragility test. Normal to MCV with abundance of cells.
Treatment: splenectomy.
G6PD deficiency
- Etiology
- Findings
Most common enzymatic disorder of RBCs. XR
Hemolytic anemia following oxidant stress (eg, sulfa drugs, antimalarials, infections, fava beans).
Back pain, hemoglobinuria a few days after oxidant stress.
Pyruvate kinase deficiency
- Hereditance
- Clinical presentation
AR.
Increases levels of 2,3-BPG. Hemolytic anemia in a newborn
Paroxysmal nocturnal hemoglobinuria
- Etiology
- Clinical presentation
- Labs
- Treatment
intravascular RBC lysis. acquired mutation in PIGA gene, with impaired GPI and decay of CD55 and CD59.
Triad: Coombs ⊝ hemolytic anemia, pancytopenia, venous thrombosis. Patients may report red or pink urine.
Labs: CD55/59 ⊝ RBCs on flow cytometry.
Treatment: eculizumab (inhibits terminal complement formation).
Sickle cell anemia
- Etiology
- Presipitants
HbS point mutation causes a single amino acid replacement in β chain (substitution of glutamic acid with valine).
low O2, high altitude, or acidosis precipitates sickling anemia, vaso-occlusive disease. “Crew cut” on skull x-ray due to marrow expansion from erythropoiesis (also seen in thalassemias).
8% of African Americans carry an HbS allele.
Sickle cell anemia
- Complications
- Aplastic crisis (due to parvovirus B19).
- Autosplenectomy
- Splenic infarct/sequestration crisis.
- Salmonella osteomyelitis.
- Painful crises (vaso-occlusive): dactylitis, priapism, acute chest syndrome, avascular necrosis, stroke.
- Sickling in renal medulla (low Po2), renal papillary necrosis, microhematuria.
Sickle cell anemia
- Diagnosis
- Treatment
hemoglobin electrophoresis.
hydroxyurea ( HbF), hydration.
HbC disease
- Etiology
- Cells morphology
Glutamic acid–to-lyCine (lysine) mutation in β-globin. Causes extravascular hemolysis.
Blood smear in homozygotes: hemoglobin Crystals inside RBCs, target cells.
Autoimmune hemolytic anemia
- Types
Warm (IgG)—chronic anemia seen in SLE and CLL and with certain drugs (eg, α-methyldopa).
Cold (IgM and complement)—acute anemia triggered by cold; seen in CLL, Mycoplasma pneumoniae infections, and infectious Mononucleosis.
Autoimmune hemolytic anemia
- Diagnosis
Autoimmune hemolytic anemias are usually Coombs ⊕.
Direct Coombs test—anti-Ig antibody (Coombs reagent) added to patient’s RBCs.
Indirect Coombs test—normal RBCs added to patient’s serum.
Microangiopathic anemia
- Etiologies
DIC, TTP/HUS, SLE, HELLP syndrome, hypertensive emergency.
Neutropenia
Absolute neutrophil count < 1500 cells/mm3
Severe infections typical when < 500 cells/mm3
Lymphopenia
Absolute lymphocyte count < 1500 cells/mm3 (
Eosinopenia
Absolute eosinophil count < 30 cells/mm3
Anormalities on Lymphoid cells caused by Corticosteroids
Corticosteroids cause neutrophilia, despite causing eosinopenia and lymphopenia.
Left shift
Increase neutrophil precursors.
Called leukoerythroblastic reaction when left shift is
seen with immature RBCs. Occurs with severe anemia or marrow response.