Heme Onc Flashcards
What is the main difference in effect between unfractioned heparin and LMWH?
Both of them can bid to AT3 to increase its activity against factor Xa.
Only unfractionated heparin is able to bind to both AT3 and thrombin, thereby allowing antithrombin to inactivate thrombin.
What is the most common viral cause for aplastic crisis for sickle cell patients?
Parvovirus B19
What effect might fibrinolytics have on heart rhythm?
They may cause a repurfusion arrhythmia on arterial reopening. These arrhytmias are usually benign.
What is the presentation for Hemolytic Uremic Syndrome? (3) What is the etiology?
- Microangiopathic hemolytic anemia
- Thrombocytopenia
- Renal insufficiency
Result of 0157:H7 E.coli, usually in undercooked ground beef
Hepcidin
- What is it/ what does it do?
- When is it released?
- Hepcidin is an acute phase reactant synthesized by the liver that acts as the central regulator of iron homeostasis. It prevents release of iron bound by ferritin
- High iron levels/ inflammatory conditions increase hepcidin synthesis. Hypoxia and increased EPO lower hepcidin levels
What is the effect of low hepcidin levels?
Low hepcidin levels increase intestinal iron absorptin and stimulate iron release by macrophages
Hairy Cell Leukemia
- What type of neoplasm?
- Presentation?
- Indolent B-cell neoplasm
- MIddle-aged men w/ bone marrow /fibrosis (leading to dry tap) + massive splenomegaly (due to red pulp infilitration) + cytoplasmic projections on lymphocytes
What is the specific deficiency in patients with Glanzmann thrombasthenia?
(GP) IIb/IIIa, needed for platelet aggregation
Abciximab MOA
It blocks the GP IIb/IIIa receptor, which normally promots platelet binding to fibrinogen
Paroxysmal nocurnal hemoglobinuria is result of an acquired mutation in what gene? What inhibitor proteins is absent and/or deficient as a result?
Mutation in the PIGA gene. This leads to absence of the GPI anchor that normally protects the RBC from complement, and associated deficiency of CD55/CD59 complement inhibitor proteins.
Dactylitis
(What is it and what is it a common presentation of?)
Painful swelling of the hands and feet
It is a common presentation of sickle cell in young children.
What effect does sickling (in SCD) have on labs?
Leads to
- Increased indirect bilirubin
- Increased lactate dehydrogenase
- Decreased haptoglobin (binds free hemoglobin and is then removed by the spleen)
What drugs do you give to reverse heparin effects? Warfarin effects?
Heparin: protamine sulfate
Warfarin: Vitamin K and Fresh Frozen Plasma (FFP)
X-linked (Bruton) agammaglobulinemia
- Caused by what?
- Effect on germinal center formation
- Presentation?
- Caused by a defect in B cell maturation, resulting in the absence of mature B cells with severe defiency of all Ig types. T cells remain fxnal and intact!
- No B cells = no germinal center formation
- Recurrent infxn in setting of intact T Lymphocyte function
Distinguish Precursor B-ALL from precursor T-ALL
This can only be done via immunophenotyping
B-ALL: TdT+, CD10+ and CD19+
T-ALL: TdT+, CD1a+, and + for T-cell markers (CD2 , 3, 4, 5, 7, and 8)
What is the role of atypical T-cells in assc. with EBV?
They function to destroy virally-infected B-lymphocytes
Patients with Down Syndrome are at an increased risk for what CA types?
ALL and AML
Tumor lysis syndrome
- When can it develop?
- What characterizes it?
- Develops during chemo for CAs with rapid cell turnover, high tumor burden, or high chemo sensitivity
- Characterized by a leak of intracellular ions (such as hyperphosphatemia, hypocalcemia, hyperkalemia, and hyperuricemia)
Prevention of Tumor Lysis Syndrome
Prevent w/ hydration + use of hypouricemic agents such as allopurinol or rasburicase
Describe the peripheral blood smear associated with lead poisoning
Coarse erythrocyte basophilic stippling and microcytic hypochromic anemia
(Leukocyte Accumulation:) What receptors are involved in:
- Rolling?
- Tight Adhesion/Crawling?
- Transmigration?
- Rolling: Selectin
- Adhesion/crawling: ICAM-1 and integrins
- Transmigration: PECAM-1 and integrins
What is the primary site for complement production?
The liver
Pure Red Cell Aplasia
- What is it?
- What dz’s is it associated with?
- Rare form of marrow failure that is characterized by severe hypoplasia of marrow erythroid elements in the setting of normal granulopoiesis and thrombopoiesis
- Assc. with Thymoma, lymphocytic leukemias and Parvovirus B19
What are the key associations with Multiple Myeloma? (7)
CRAB (hyperCalcemia, Renal involvement, Anemia, Bone lytic lesions/Back Pain)
+
Primary amyloidosis, Rouleaux formation, and numerous plasma cells w/in bone marrow sample
What is the marker for hematopoietic stem cells?
CD34+
Chloramphenicol AE
This antibiotic can lead to both dose-dependent (reversible) cytopenias and dose-independent (irreversible) aplastic anemia.
Which components of the skin drain to the superficial inguinal lymph nodes?
All skin from the umbilicus down, including the anus (below the pectinate line), excluding the testes, glans penis, and posterior calf
Potential complications from hereditary spherocytosis (2)
- Pigmented gallstones
- Aplastic crises from parvovirus B19 infection
Name the pentad for Thrombotic thrombocytopenic purpura
- Neurologic symptoms
- Renal failure
- Fever
- Thrombocytopenia
- Microangiopathic hemolytic anemia
