Hematology & Oncology Flashcards
This deck covers Chapters 111-115 in Rosens, compromising all of hematology and oncology.
Differentiate TTP/HUS from DIC and Liver Infarct
- TTP/HUS have normal coags
- DIC has abnormal coags
- Liver infarct has elevated Factor VIII
What is thalassemia? What are the types of thalassemia? Is the RDW normal? What might you see on smear?
Thalassemia
- Abnormal alpha or beta-globin gene(s)
Workup
- RDW normal
- MCV very low (50s - 60s)
- Target cells and basophilic stippling on smear
Types
- Major: Homozygous B
- Transfusion dependent
- HSM, jaundice, abnormal development, typical facies, premature death
- Patients are transfusion dependent
- Tx: Transfusion + Fe-chelation therapy
- Minor: Heterozygous B
- Elevated HbA2 (alpha/delta) on electrophoresis
- Tx: None necessary
- α-Thalassemia
- Range from asymptomatic carrier to prenatal death
- 4 gene deletion - no α chains, only B = 4γ tetramers / hydrops fetalis
- 3 gene deletion – HbH in adults = 4β tetramers – hang onto oxygen too tightly – poor offloading to tissues (but you still produce SOME α-chains so compatible with life)
Provide a differential for normocytic anemia
ABCDs
- Acute blood loss
- Bone marrow failure
- Chronic disease
- Destruction (hemolysis)
- Spherocytosis (hereditary)
What is the underlying problem in Hemophilia A? How do you dose the treatment?
Factor 8 deficiency
- Mild: DDAVP 0.3 mcg/kg (max 20 mcg)
- Moderate: 25 u/kg
- Severe/Life Threat: 50 u/kg
List 10 potential organs damaged in Sickle Cell Disease
- Brain: strokes
- Retinal hemorrhage, Ischaemic neuropathy
- Lung infarcts
- Spleen: Functional asplenia by age 5
- Heart: CHF
- Skin: ulcers
- Gallstones
- GU: hematuria, priapism
- Skeletal: osteomyelitis, infarct
- Blood: immune deficiency, hemolysis
List 6 non-malignant causes of SVC syndrome
- Goiter
- Pericardial constriction
- Primary thrombosis
- Idiopathic sclerosing aortitis
- Tuberculous mediastinitis
- Fibrosing mediastinitis (histo + methysergide treatment)
- Arteriosclerotic or (rarely) syphilitic aneurysm
- Nephritic syndrome
- Indwelling CVCs
You’re working up a patient for anemia NYD and your lab results come back. MCV is low, low iron, low ferritin, high TIBC. Diagnosis?
Iron Deficiency
What is von Willebrand’s disease? How do you treat it?
Von Willebrand Disease
- Autosomal dominant disorder – common
- vWF is normally involved in PLT adhesion
- vWD leads to factor VIII deficiency, abnormal platelet adhesiveness, and abnormal vascular endothelium
- Similar symptoms to thrombocytopenia rather than hemophilia
Types
- Type 1 (90%) = decrease in vWF
- Type 2 = qualitative issue – 5 subtypes
- Type 3 = same as 1 but severe form – homozygous
Labs
- Platelets normal
- Prolonged BT
- Decreased F8 activity
- INR normal
- aPTT increased
- vWF decreased
Treatment
- Mild/Moderate bleeding
- DDAVP 0.3mcg/kg
- Severe bleeding
- vWF or F8 concentrate 50 U/kg
- Cyro (F8, F13, Fibrinogen, vWF)
- FFP
- TXA
List 6 causes of rapid intravascular RBC destruction
- DIC and mechanical hemolysis
- Massive burns
- Toxin (Brown recluse spiders/Cobras)
- Infections (Malaria, Clostridium)
- G6PD
- ABO incompatibility
- Cold agglutinin hemolysis (Mycoplasm, EBV)
- Paroxysmal nocturnal hemoglobinuria (PNH)
- Immune complex hemolysis
List 5 causes of hyperviscosity syndrome
- Waldenstrom’s macroglobulinemia (MCC)
- Multiple myeloma
- Cryoglobulinemia
- Leukemias
- Leukemoid reaction
- Polycythemia vera
- Accumulation of abnormal Hb in sickle cell
Blastic phase of CML, chronic granulocytic leukemia
Blast cell crisis of ALL, non-lymphoblastic leukemias
You give a hemophilia A patient factor replacement and they’re still bleeding, what likely happened?
Antihemophilic factor antibodies post-infusion
Treatment
- Just give more Factor
- Exchange plasmapheresis
- Immunosuppressive therapy
- Prothrombin complexes with activated clotting factors
- Recombinant activated Factor VIIa
Describe the pathophysiology and treatment of ITP
Immune Thrombocytopenia Purpura
- Autoimmune reaction with IgG against platelets
- Diagnosis of exclusion
Acute ITP
- Children 2-6 yo with a viral prodrome
- Platelets <20
- Self-limited, >90% rate of spontaneous remission
- Tx = supportive. Only give steroids and IVIG to bleeders.
Chronic ITP
- Adults (women > men)
- Gradual, no prodrome
- Platelets 30-100
- Long term mortality low (1%)
- Tx = Prednisone 1 mg/kg + IVIG
What are the common signs & symptoms of hypercalcemia in malignant disease?
- Neuro: Muscle weakness, fatigue, hyporeflexia, lethargy
- Cardio: Short PR/QT, wide T, heart block, bradycardia
- GI: N/V, constipation
- GU: Polyuria, polydipsia
- Derm: pruritus
Name 6 diseases associated with autoimmune hemolytic anemia (AIHA)?
Autoimmune Hemolytic Anemia
- RA
- SLE
- PAN
- Malaria
- Syphilis
- Mycoplasm
- Malignancy: CLL/CML, ovarian teratoma
- Ulcerative colitis
List 6 drugs commonly implicated in thrombocytopenia
- Quinine
- Heparin
- Digoxin
- Sulfonamides
- Phenytoin
- ASA
- Alcohol
- GP IIb-IIIa inhibitors
- Cocaine (IV)
How do you reverse heparin?
- Protamine 1 mg per:
- 100 units UFH
- 1 mg LMWH
- Give IV over 10-15 minutes
Describe the pathophysiology and treatment of HUS
Verotoxin-producing bacteria
- >90% cases from E. Coli 0157:H7
- Mycoplasm also implicated
- Childhood illness
- Bloody diarrhea
Treatment
- Fluids, supportive
- Dialysis
- AVOID antibiotics and antimotility agents
- No plasmapheresis in children
TTP/HUS = normal PT/INR/PTT/FDPs/D-dimer/fibrinogen
Explain how platelets help hemostasis
- Exposed collagen from injury
- vWF binds exposed collagen
- Platelets bind vWF and release ADP and TXA2
* Causes vasoconstriction and aggregation - Plug formation
- Clotting factors bind the plug
Explain the pathophysiology of sideroblastic anemia. What are the RBC indices for this disease? What is the treatment?
Sideroblastic Anemia
Pathophysiology
- Defect in porphyrin synthesis = impaired Hb synthesis
- Excess Fe in mitochondria of RBC precursor
- Typically a disease of the elderly
- Look for pallor, splenomegaly, microcytic anemia, iron OL
RBC indices
- Increased serum Fe, ferritin & transferrin (TIBC) saturation
Treatment
- Pyridoxine (vitamin B6) 100 mg TID x 1-2 months
- Often need blood transfusions (+ Fe-chelation)
List 4 mechanisms of hypercalcemia in cancer
Patients with no bone disease (80%)
- Hypercalcemia from tumor-made hormone substances
- Examples: PTHrP, prostaglandins, peptides
Patients with metastatic bone involvement (20%)
- Ca + PO4 release from osteoclasts in the bone
Lymphomas that secrete 1,25(OH)2D
- Calcitriol, the active form of Vitamin D (<1%)
Ectopic hyperparathyroidism (<1%)
What is the issue with hemophilia B? How much factor must you give?
Hemophilia B
- Factor 9 deficiency
Treatment
- Mild/Moderate = 50 units/kg
- Severe = 100 units/kg (150 units/kg if <15 yo)
Describe the pathophysiology and treatment of TTP
FATRN
- Fever
- Anemia
- Thrombocytopenia
- Renal Impairment
- Neurological Sequelae
Pathophysiology
- Antibodies to ADAMTS13 – protease that cleaves vWF
- Multimers cause PLT aggregation, thrombosis, and MAHA
- Similar to HUS but TTP has ↑CNS and ↓renal sx
- TTP/HUS = normal PT/INR/PTT/D-dimer/Fibrinogen
Treatment
- Plasmapheresis
- Prednisone (1 mg/kg)
- Heme consult
What is paroxysmal nocturnal hemoglobinuria (PNH)? What is the major complication? What intervention can be life-threatening in these patients?
Paroxysmal Nocturnal Hemoglobinuria
- Stem cell defect
- Causes abnormal RBC, PMN, and platelet sensitivity to complement
- Chronic hemolysis, hemosiderinuria, decreased WBC, decreased PLT
Complications
- Clotting/DVT
Life-threatening intervention
- Transfusion
- RBC lysis from donor complement
- Can only use washed out packed cells