Hematology and oncology- Phatology (2) Flashcards
Lead poisoning
- Clinical features
Microcytic anemia, GI and kidney disease.
Children—exposure to lead paint mental deterioration.
Adults—environmental exposure (eg, batteries, ammunition) headache, memory loss, demyelination
Acute intermittent porphyria
- Etiology
- Accumulate substrates
Porphobilinogen deaminase (uroporphyrinogen I synthase). AD
Porphobilinogen, ALA
Acute intermittent porphyria
- Symptoms
- Treatment
(5 P’s): Painful abdomen Port wine–colored urine Polyneuropathy Psychological disturbances Precipitated by drugs (eg, cytochrome P-450 inducers), alcohol, starvation
Treatment: hemin and glucose, which inhibit ALA synthase.
Porphyria cutanea tarda
- Etiology
- Accumulate substrates
- Symptoms
- Treatment
Uroporphyrinogen decarboxylase. AD
Uroporphyrin (teacolored urine)
Blistering cutaneous photosensitivity and hyperpigmentation.
Most common porphyria. Exacerbated with alcohol consumption. Associated with hepatitis C.
Iron poisoning
- Mechanism
- Symptoms
- Treatment
Cell death due to peroxidation of membrane lipids.
Nausea, vomiting, gastric bleeding, lethargy, scarring leading to GI obstruction.
Chelation (eg, IV deferoxamine, oral deferasirox) and dialysis.
*high mortality rate with accidental ingestion by children.
Coagulation Tests
- PT
- INR
- PTT
Tests function of common and extrinsic pathway (factors I, II, V, VII, and X).
Calculated from PT. 1 = normal, > 1 = prolonged.
Tests function of common and intrinsic pathway (all factors except VII and XIII)
Hemophilia A, B, or C
- Test altered
- Clinical manifestations
- Treatment
Intrinsic pathway coagulation defect (High PTT).
Hemorrhage in hemophilia—hemarthroses easy bruising, bleeding after trauma or surgery.
Desmopressin + factor VIII concentrate (A); factor IX concentrate (B); factor XI concentrate (C).
Platelet disorders
- Test altered
- Clinical manifestations
- Etiologies
Defects in platelet plug formation, increas bleeding time (BT).
Microhemorrhage: mucous membrane bleeding, epistaxis, petechiae, purpura.
Bernard-Soulier, Glanzmann thrombasthenia, HUS, PTT, Immune thrombocytopenia.
Bernard-Soulier syndrome
- Etiology
- Labs
Defect in platelet plug formation. Large platelets. GpIb defect.
Abnormal ristocetin test that does not correct with mixing studies.
Glanzmann thrombasthenia
- Etiology
- Labs
Defect in platelet integrin αIIbβ3 (GpIIb/IIIa).
Labs: blood smear shows no platelet clumping.
HUS
- Labs
- Etiology
- Treatment
thrombocytopenia, microangiopathic hemolytic anemia, and acute renal failure.
Typical HUS is seen in children, accompanied by diarrhea. (EHEC) (eg,O157:H7)
Same spectrum as TTP, with a similar clinical presentation and same initial treatment of plasmapheresis
Immune thrombocytopenia
- Etiology
- Labs
- Treatment
Anti-GpIIb/IIIa antibodies, splenic macrophage consumption of platelet-antibody complex.
megakaryocytes on bone marrow biopsy.
Steroids, IVIG; rituximab or splenectomy for refractory ITP.
TTP
- Etiology
- Labs
Inhibition or deficiency of ADAMTS 13 (vWF metalloprotease). large vWF multimers, platelet adhesion, platelet aggregation and thrombosis.
schistocytes, LDH, normal coagulation parameters.
TTP
- Clinical manifestations
- Treatment
(FAT RN): pentad of Fever, microangiopathic hemolytic Anemia, Thrombocytopenia, Renal failure, Neurologic symptoms.
Treatment: plasmapheresis, steroids.
Disseminated intravascular coagulation
- Etiologies
“STOP Making New Thrombi”
Sepsis (gram ⊝), Trauma, Obstetric complications, acute Pancreatitis, Malignancy, Nephrotic syndrome, Transfusion
Disseminated intravascular coagulation
- Labs
schistocytes, fibrin degradation products (d-dimers), fibrinogen, factors V and VIII.
Hereditary thrombosis syndromes leading to hypercoagulability
Antithrombin deficiency, Factor V Leiden, Protein C or S
deficiency, Prothrombin gene mutation
Antithrombin deficiency
- Etiologies
Inherited deficiency of antithrombin: diminishes the increase in PTT following heparin administration.
Can also be acquired: renal failure/nephrotic syndrome.
Factor V Leiden
- Etiology
- Epidemiology
Mutant factor V. Arg506Gln mutation. Resistant to degradation by activated protein C.
Most common cause of inherited hypercoagulability in Caucasians.
Protein C or S deficiency
- Etiology
- Complications
Decrease ability to inactivate factors Va and VIIIa.
risk of thrombotic skin necrosis with hemorrhage after administration of warfarin.
Together, protein C Cancels, and protein S Stops, coagulation.
Blood transfusion (Packed RBCs)
- Effect
- Clinical use
Increase Hb and O2 carrying capacity.
Acute blood loss, severe anemia
Blood transfusion (Platelets)
- Effect
- Clinical use
Increase platelet count.
Stop significant bleeding (thrombocytopenia, qualitative platelet defects)
Blood transfusion (Fresh frozen plasma (FFP)/prothrombin complex concentrate(PCC))
- Effect
- Clinical use
FFP contains all coagulation factors and plasma proteins; PCC contains factors II, VII, IX, and X, as well as protein C and S.
DIC, cirrhosis, immediate anticoagulation reversal
Blood transfusion (Cryoprecipitate)
- Effect
- Clinical use
Contains fibrinogen, factor VIII, factor XIII, vWF, and fibronectin
Coagulation factor deficiencies involving fibrinogen and factor VIII
Hodgkin lymphoma
- Spread
- Characteristic cells
Localized, single group of nodes; contiguous
spread. Overall prognosis better than that of non-Hodgkin
Reed-Sternberg cells. 2 owl eyes × 15 = 30. RS cells are CD15+ and CD30+ B-cell origin.
Hodgkin lymphoma
- Occurs in
- Associations
young adulthood and > 55 years; more common in men except for nodular sclerosing type.
Associated with EBV.
Hodgkin lymphoma
- Types
- Nodular sclerosis: Most common
- Lymphocyte rich: Best prognosis
- Mixed cellularity: Eosinophilia, seen in immunocompromised patients
- Lymphocyte depleted: Seen in immunocompromised patients
Non-Hodgkin lymphoma
- Spread
- Cells affected
- Ocurrs in
- Associations
Multiple lymph nodes involved; extranodal involvement common; noncontiguous spread.
Majority involve B cells; a few are of T-cell lineage.
in children and adults.
May be associated with HIV and autoimmune diseases.
Burkitt lymphoma
- Occurs in
- Genetics
- Cell morphology
- Presentation
Adolescents or young adults.
t(8;14)—translocation of c-myc (8) and heavy-chain Ig (14)
“Starry sky” appearance, sheets of lymphocytes with interspersed “tingible body” macrophages. Associated with EBV.
Jaw lesion in endemic form in Africa; pelvis or abdomen in sporadic form.
Diffuse large B-cell lymphoma
- Occurs in
- Genetics
Usually older adults, but 20% in children.
Alterations in Bcl-2, Bcl-6.
*Most common type of non-Hodgkin lymphoma in adults
Follicular lymphoma
- Occurs in
- Genetics
- Presentation
Adults
t(14;18)—translocation of heavy-chain Ig (14) and BCL-2 (18)
Presents with painless “waxing and waning” lymphadenopathy.
Mantle cell lymphoma
- Occurs in
- Genetics
- Presentation
Adult males
t(11;14)—translocation of cyclin D1 (11) and heavy-chain Ig (14), CD 5+
Very aggressive, patients typically present with late-stage disease.
Marginal zone lymphoma
- Occurs in
- Genetics
- Association
Adults
t(11;18)
Associated with chronic inflammation
Primary central nervous system lymphoma
- Occurs in
- Association
Adults
Most commonly associated with HIV/AIDS; pathogenesis involves EBV infection.
*needs to be distinguished from toxoplasmosis via CSF analysis or other lab tests.
Adult T-cell lymphoma
- Occurs in
- Association
- Presentation
Adults
Caused by HTLV (associated with IV drug abuse)
present with cutaneous lesions; common in Japan, West Africa, and the Caribbean. Lytic bone lesions, hypercalcemia.
Mycosis fungoides/ Sézary syndrome
- Occurs in
- Clinical Characteristics
Adults
Skin patches/ plaques (cutaneous T-cell lymphoma), characterized by atypical CD4+ cells with “cerebriform” nuclei and intraepidermal neoplastic cell aggregates
(Pautrier microabscess).
May progress to Sézary syndrome (T-cell leukemia).
Multiple myeloma
- Clinical manifestations
CRAB:
HyperCalcemia
Renal involvement
Anemia
Bone lytic lesions/Back pain
Multiple myeloma
- Associated with
susceptibility to infection
Primary amyloidosis (AL)
Punched-out lytic bone lesions on x-ray
M spike on serum protein electrophoresis
Ig light chains in urine (Bence Jones protein)
Rouleaux formation B (RBCs stacked like poker chips in blood smear)
Bone marrow > 10% monoclonal plasma cells
Monoclonal gammopathy of undetermined significance (MGUS)
Bone marrow < 10% monoclonal plasma cells, asymptomatic, Develop myeloma at a rate of 1–2% per year. No CRAB findings.
Waldenström macroglobulinemia
M spike = IgM hyperviscosity syndrome (eg, blurred vision, Raynaud phenomenon); no CRAB findings.
Myelodysplastic syndromes
Stem-cell disorders involving ineffective hematopoiesis defects in cell maturation of nonlymphoid lineages.
Risk of transformation to AML.
*Pseudo–Pelger-Huet anomaly—neutrophils with bilobed (“duet”) nuclei. Typically seen after chemotherapy.
Leukemias
Unregulated growth and differentiation of WBCs in bone marrow marrow failure anemia, infections (Lowmature WBCs), and hemorrhage (Low platelets)
Acute lymphoblastic leukemia/lymphoma
- Occurs in
- Presentation
- Markers
- Prognosis
in children. T-cell ALL can present as mediastinal mass (presenting as SVC-like syndrome). Associated with Down syndrome.
Peripheral blood and bone marrow have increased lymphoblasts
TdT+ (marker of pre-T and pre-B cells), CD10+ (marker of pre-B cells).
Most responsive to therapy. May spread to CNS and testes. t(12;21) better prognosis.
Chronic lymphocytic leukemia/small lymphocytic lymphoma
- Occurs in
- Markers
- Presentation
Age > 60 years. Most common adult leukemia.
CD20+, CD23+, CD5+ B-cell neoplasm.
Often asymptomatic, progresses slowly; smudge cells. autoimmune hemolytic anemia.
Richter transformation
CLL/SLL transformation into an aggressive lymphoma, most commonly diffuse large B-cell lymphoma (DLBCL).
Hairy cell leukemia
- Occurs in
- Clinical Features
- Diagnosis
Adult males. Mature B-cell tumor. lymphadenopathy is uncommon.
Causes marrow fibrosis dry tap on aspiration. Patients usually present with massive splenomegal and pancytopenia.
Stains TRAP (tartrate-resistant acid phosphatase) ⊕. TRAP stain largely replaced with flow cytometry.
Acute myelogenous leukemia
- Occurs in
- Morphology
- Risk factors
Median onset 65 years.
Auer rods; myeloperoxidase ⊕ cytoplasmic inclusions seen mostly in APL; circulating myeloblasts on peripheral smear.
Risk factors: prior exposure to alkylating chemotherapy, radiation, myeloproliferative disorders, Down syndrome.
*APL: t(15;17), responds to all-trans retinoic acid (vitamin A). DIC its a common presentation.
Chronic myelogenous leukemia
- Occurs in
- Genetics
- Presentation
- Treatment
peak incidence 45–85 years, median age at diagnosis 64 years.
Defined by the Philadelphia chromosome (t[9;22], BCR-ABL) and myeloid stem cell proliferation.
Presents with dysregulated production of mature and maturing granulocytes and splenomegaly. May accelerate and transform to AML or ALL (“blast crisis”).
Responds to bcr-abl tyrosine kinase inhibitors (eg, imatinib, dasatinib)
Chronic myeloproliferative disorders
polycythemia vera, essential thrombocythemia, myelofibrosis, and CML.
Associated with V617F JAK2 mutation.
*Pag 422
Langerhans cell histiocytosis
- Definition
- Presentation
- Markers and characteristic granules
Proliferative disorders of dendritic (Langerhans) cells.
Presents in a child as lytic bone lesions and skin rash or
as recurrent otitis media with a mass involving the mastoid bone.
Cells express S-100 (mesodermal origin) and CD1a. Birbeck granules (“tennis rackets” or rod shaped on EM) are characteristic.
Tumor lysis syndrome
- hyperkalemia
- hyperphosphatemia, hypocalcemia due to Ca2+ sequestration by PO4
- hyperuricemia acute kidney injury
Prevention and treatment include aggressive hydration, allopurinol, rasburicase.