Hematology and Oncology Flashcards
List the 3 most common cancers in women
- breast
- lung (most deaths)
- colorectal
Cancer immunotherapy often includes administration of monoclonal antibodies against a target overexpressed on the cancer cell surface. The Fc portion of the antibody binds ____ cells via CD___ leading to cytotoxicity
natural killer
CD16
What clotting factors are produced initially by the liver in an inactive form and then activated by vitamin K dependent carboxylatoin
II
VII
IX
X
PT will be prolonged in cirrhosis primarily due to what deficiency
factor VII (shortest half life, produced by the liver, and part of the extrinsic pathway which effects PT)
Nitrates are oxidizing agents that are effective in treating ___ poisoning due to their ability to induce methemoglobinemia which contains ___ instead of _____
cyanide
ferric (FE3+)
ferrous (Fe4+)
(cyanide binds ferric iron m ore avidly than to mitochondrial cytochrome enzymes, diminshing cyanides toxic effect)
Patients with sickle cell disease become functionally asplenic within the first few years of like which dramatically increases the risk for infections with encapsulated organsims, particularly ____
streptococcus pneumoniae
also at increased risk for salmonella osteolmyelits
What medications are most commonly known to cause pancytopenia
antiseizure: carbamazepine, valproic acid
sulfonamides
nifedipine
Thrombotic thrombocytopenic purpura is a thrombotic microangiopathy resulting in ____ and ____ which are both findings that are essential for making the diagnosis
microangiopathic hemolytic anemia
thrombocytopenia
Thrombotic thrombocytopenia purpura is triggered by a severe deficiency in ______
ADAMTS13
What kind of receptor is HER2
tyrosine kinase
Tx for HER2 positive breast cancer
trastuzumab
What is the result of mycoplasma pneumoniae causing cross-reacting IgM antibodies
mild, transient hemolytic anemia
CD19 is only expressed by what cells
B cells
Vincristine has what classic toxicity and it stops the cell cycle at what stage
neurotoxicity (peripheral neuropathy) M phase (disrupts neuronal microtubules)
HbF contains __ globin instead of ___ globin seen in HbA
gamma
beta
Diagnostic lab values for DIC
prolonged PT/PTT
thrombocytopenia (due to consumption of coagulation factors and platelets)
Erythropoietin signal transduction is primarily mediated by _____ which promotes erythrocyte precursor survival
JAK2/STAT
Porphyria cutanea tarda is causes photosensitivity (blistering) and hyperpigmentation and is caused by a deficiency in what enzyme
late steps in porphyrin synthesis: uroporphyrinogen decarboxylase
acute intermittent porphyria causes abdominal and neurological symptoms and is caused by a deficiency in what enzyme
early steps of porphyrin synthesis: porphobilinogen deaminase
Parvovirus is what type of virus? (DNA/RNA, positive sense, negative sense, single strand, double strand, enveloped, nonenveloped)
nonenveloped sing-stranded DNA virus
In Von Willebrand disease, how platelet levels, PT and PTT be affected
platelets and PT normal
PTT prolonged due to low levels of factor VIII
What are the main side effects of cyclin dependent kinase inhibitors
inhibit cellular replication in rapidly dividing cells (bone marrow, neutropenia, leukopenia, anemia)
What can cause peripheral neuromuscular excitability (paresthesia, muscle spasms) following a blood transfusion
citrate anticoagulants can chelate plasma calcium –> hypocalcemia
What is the underlying pathology of primary/hereditary hemochromatosis
mutation in HFE protein that causes enterocytes and hepatocytes to detect falsely low iron levels –> increased DMT1 expression on enterocytes to increased iron intestinal absorption and hepatocytes decrease hepcidin synthesis which increases ferroportin expression allowing increased iron secretion into circulation
what are the clinical features of primary hemochromatosis
micronodular cirrhosis
diabetes mellitus
skin pigmentation (bronze diabetes)
increased risk for hepatocellular carcinoma, congestive heart failure, and testicular atrophy
enoxaparin MOA
low molecular weight heparin
What type of leukemia can cause respiratory symptoms such as a child presenting with dyspnea, tachypnea, and inspiratory stridor as well as dysphagia with solid foods
T-cell acute lymphoblastic leukemia (ALL)
can cause a mediastinal mass
What is the MOA of emicizumab treating hemophilia A
mimics activity of factor VII
bispecific monoclonal antibody that binds both factor IXa and factor X bringing them in close proximity to allow for factor X activiation
Sickle cell anemia results from a point mutation that substitutes ____ in the place of ____
valine
glutamic acid
Why does unfractionated heparin have equal activity against factor Xa and thrombin while LMWH has greater activity against factor Xa than thrombin
only unfractionated heparin has pentasaccharide chain long enough to bind to both antithrombin and thrombin which is required to inactivate thrombin
both of them can bind anitithrombin, though, which is all that is needed to increase its ability to inactivate factor Xa
Symptoms of colicky abdominal pain, constipation, and peripheral neuropathy in the presence of a microcytic anemia with normal iron studies suggests what diagnosis
lead poisoning
what does a peripheral smear in lead poisoning show
microcytic anemia that may reveal basophilic stippling
What are causes of target cells (RBCs)
reduced cell volume: thalassemia, iron deficiency
excessive cell membrane: obstructive liver disease, postsplenectomy
How does carbon monoxide poisoning affect O2 binding to hemoglobin
heme binds CO stronger than O2 but it also decreases hemoglobin O2 unloading
A 50 yr old man with painless mass in his neck that fluctuates in size and has a t(14;18) chromosomal translocation has overexpression of what gene and type of lymphoma is this
BCL2 (18) follicular lymphoma (a non hodgkin lymphoma)
Apixaban blocks the conversion of ___ to ____
prothrombin
thrombin
(direct factor Xa inhibitor)
In erythrocytosis, a normal red blood cell mass indicates what as the cause of polycythemia
plasma volume contraction (relative erythrocytosis)
How does multiple myeloma cause bone pain
secretes RANKL and destroys osteoprotegerin –> increased RANK activity –> osteoclast differentiation and inhibition of osteoblasts –> purely radiolucent/osteolytic bone lesions
What chemotherapy agent can cause lung toxicity that usually manifests as pulmonary fibrosis
bleomycin
what is the MOA of bleomycin
binds to iron and oxygen molecules to create free radicals that cause DNA strand breaks
What location of enlarged lymph nodes is unlikely to be caused by common childhood infections and is concerning for malignancy: anterior cervical posterior cervical submandibular submental supraclavicular
supraclavicular
How does the BCL2 protein normally inhibit apoptosis
blocking the release of proapoptotic factors (cytochrome C protein) from the mitochondria
What lymphoma presents with a painless waxing and waning (fluctuating) lymphadenopathy
follicular lymphoma (most common indolent (painless) non hodgkin lymphoma in adults)
Vitamin B12 is an essential cofactor in the recycling of ____ to ____ which is required for amino acid, purine, and thymidine synthesis
5-methyl-tetrahydrofolate
tetrahydrofolate
(B12 = colbalamin)
____ is a polypeptide synthesized by the _____ that acts as a regulator of intestinal iron absorption and iron release by macrophages
hepcidin
liver
(hypoxia and high erythropoiesis –> low hepcidin –> increased intestinal absorption and stimulate iron release from macrophages)
what complication of multiple myeloma can lead to renal failure, heart failure, and neurologic dysfunction
amyloidosis (light chains form insoluble fibrils)
Acute promyelocytic leukemia is associated with what chromosomal translocation
t(15;17)
Auer rods = ______
acute myelogenous leukemia (includes acute promyelocytic leukemia)
Tumor lysis syndrome has what effect on the following: potassium uric acid phosphorus lactate dehydrogenase
potassium: increased (–> hypocalcemia)
uric acid: increased
phosphorous: increase
lactate dehydrogenase: increased
What causes the delay in warfarin’s therapeutic effect
it only blocks the generation of new clotting factors, therapeutic effect is delayed 3-5 days until preexisting clotting factors are consumed
What 3 things can cause a left shift in the hemoglobin oxygen dissociation curve
increased pH
decreased 2,3-bisphosphoglycerate (increased in low O2 and decreases O2 affinity allowing release in peripheral tissues)
decreased
temperature (stabilizes bonds)
hemolytic anemia, hypercoagulability, and pancytopenia are characteristic of what disease
paroxysmal nocturnal hemoglobinuria
Paroxysmal nocturnal hemoglobinuria is caused by an acquired mutation of the ___ gene which is involved in the synthesis of _______
PIGA
glycosylphosphatidylinositol (GPI) anchor
what is the pathogenesis of paroxysmal nocturnal hemoglobinuria
mutation in gene for GPI anchor synthesis –> CD55 (decay-accelerating factor) and CD59 (MAC inhibitory protein) deficiencies –> complement mediated hemolysis (no inhibition of complement on RBC)
flow cytometry is the gold standard for diagnosis of paroxysmal nocturnal hemoglobinuria which will show absence of ___ and ____
CD55
CD59
megaloblastic anemia with neurologic dysfunction is due to what deficiency
B12
What lymphoma has presence of macrophages and apoptotic bodies in a see of medium-sized lymphocytes
Burkitt
Burkitt lymphoma is associated with what chromosome translocation
t(8;14)
8: c-Myc
Acute intermittent porphyria can cause neurologic symptoms and abdominal pain due to deficiency of what enzyme and can be treated by decreasing activity of what enzyme
porphobilinogen deaminase aminolevulinate synthase (rate limiting enzyme in hepatic pathway of heme)
Methotrexate is a _____ antagonist which competitively inhibits the enzyme _____ which catalyzes the synthesis of ______.
folic acid
dihydrofolate (DHF) reductase
tetrahydrofolate
Lecovorin/folinic acid has what affect on methotrexate vs 5-FU chemotherapeutic effects
methotrexate: inhibited (bc leucovorin bypasses the DHF reductase step that is inhibited by methotrexate)
5-FU: potentiates toxicity (5-FU requires presence of reduced folate inorder to form complexes with thymidylate synthase)
list 3 B cell markers
CD19
CD20
CD23
A patient with anemia, thrombocytopenia, and leukocytosis with a predominance of CD-20 positive cells has high suspicion of what diagnosis
chronic lymphocytic leukemia (CLL)
The restocetin cofactor assay measures platelet agglutination via binding of ____ receptors to ____. It is abnormal in what deficiency?
glycoprotein 1b
vWF deficiency
The primary immune response to EBV is through what cells which appear in the peripheral blood smear as what
CD8 T lymphocytes
reactive (atypical) CD8 T cells
jaundice, dark urine, normocytic anemia, reticulocytosis, and bite cells are indicative of what diagnosis
glucose 6 phosphate dehydrogenase deficiency
Rasburicase MOA
recombinant version of urate oxidase
converts uric acid into allantoin that is more soluble
used in tumor lysis syndrome
Erythrocytes always convert glucose to pyruvate but have what alternate pathway of doing so that does not generate ATP
bisphosphoglycerate mutase converts 1,3BPG into 2,3BPG
2,3BPG is converted to 3 phosphoglycerate by bisphosphoglycerate phosphatase and neither of these steps yield ATP
vWF functions as a promotor of platelet adhesion at sites of vascular injury by binding ____ to ____
platelet glycoproteins (primarily Gp1b) subendothelial collagen on injured blood vessel walls
Hemoglobin C is caused by a ___ mutation that results in a ___ residue being substituted by ____ in the beta globin chain
missense
glutamate
lysine