Hem Onc Flashcards
1
Q
What are the platelet receptors for vWF and fibrinogen respectively?
A
vWF - GPIb. Fibrinogen - GPIIb/IIIa
2
Q
How do reticulocytes show up under Wright-Giemsa stain and why?
A
Blue due to ribosomal RNA presence
3
Q
What causes the green color in most pus and sputum?
A
Myeloperoxidase from neutrophils (contains heme)
4
Q
What is the most common cause of hypersegmented PMNs?
A
Folate deficiency
5
Q
Causes of eosinophilia
A
NAACP. Neoplastic, Asthma, Allergic process, Collagen vascular disease, Parasites
6
Q
How does induction therapy work?
A
Prevents allergies by inducing blocking antibody (IgG against allergen) by introducing small amounts of allergen over time. Prevents IgE-mast cell interaction
7
Q
What type of antibodies are anti-AB and anti-Rh respectively?
A
Anti-AB are IgM, anti-rh are IgG
8
Q
What factor is specifically measured by the PT?
A
VII
9
Q
What factors does antithrombin inhibit?
A
7, 9, 10, 11, 12
10
Q
What factors do protein C and S inhibit?
A
5 and 8 (but not 5 leiden)
11
Q
Between the PT and aPTT which measures the intrinsic pathway and which the extrinsic?
A
PT measures extrinsic, aPTT measures intrinsic
12
Q
Pathology associated with spur cells (acanthocytes)
A
Liver disease, abetalipoproteinemia
13
Q
Pathology associated with basophilic stippling
A
Thalassemias, Anemia of chronic disease, Iron deficiency, Lead poisoning (w/ hypochromic microcytic anemia)
14
Q
Pathology associated with bite cells
A
G6PD deficiency
15
Q
Pathology associated with schistocytes, helmet cells
A
DIC, TTP/HUS, Traumatic hemolysis
16
Q
3 causes of DIC
A
Gram negative sepsis, Acute pancreatitis, Burn injury
17
Q
Common cause of TTP/HUS
A
E Coli 0157 (ask about a recent diarrheal illness)
18
Q
Pathology associated with teardrop cells
A
Bone marrow infiltration (eg. myelofibrosis)
19
Q
Pathology associated with target cells
A
HbC, Asplenia, Liver disease, Thalassemia
20
Q
Pathology associated with Heinz bodies
A
Alpha-thal, G6PD deficiency. Due to oxidation of iron from ferrous to ferric denaturing hemoglobin
21
Q
Pathology associated with Howell-Jolly bodies
A
Function hyposplenia or asplenia. Due to basophilic nuclear remnants in RBCs
22
Q
Types of alpha thalassemias
A
4 gene deletion - Hb Barts (g4) is incompatible with life. 3 gene deletion - HbH disease (b4). 1-2 gene deletion - no significant anemia
23
Q
How do you confirm the diagnosis of b-thal minor?
A
Increased HbA2 (>3.5 percent) on electrophoresis
24
Q
What is increased in major and minor b-thal?
A
HbF
25
X-ray finding in b-thal major
Crew cut skull x-ray (marrow expansion). Also Chipmunk facies
26
What heme synthesis enzymes are inhibited by lead?
ALA dehydratase and ferrochelatase
27
Lines on gingivae and epiphyses on x-ray, encephalopathy and erythrocyte basophilic stippling, abdominal colic, sideroblastic anemia, wrist and food drop
Lead poisoning
28
Treatment for lead poisoning
EDTA and Dimercaprol. Succimer for kids
29
Defect and genetics in sideroblastic anemia
X-linked defect in gamma-ALA synthase. Can also be caused by alcohol and lead. Will find increased iron, normal TIBC, increased ferritin
30
Treatment for sideroblastic anemia
Pyridoxine (B6)
31
What leads to thalassemias?
Mutations that cause defective mRNA processing (a mutation 3 bases upstream of start codon interferes w mRNA binding to ribosome)
32
How do you distinguish folate deficiency from B12 deficiency.
B12 will come with neuro signs. Also, normal methylmalonic acid in folate def, but increased in B12 def
33
What compound is found in increased levels in both folate and B12 deficiency?
Homocysteine
34
What are the main spinal cord areas targeted by B12 deficiency?
Posterior columns (vibration/proprio) and lateral corticospinal tract (spasticity)
35
How do you distinguish B12 deficiency from tabes dorsalis?
Lateral corticospinal tract affected in B12 deficiency but not in tabes dorsalis
36
A few drugs that cause nonmegaloblastic macrocytic anemia (3)
5-FU, AZT, hydroxyurea
37
Findings in intravascular hemolysis
Decreased haptoglobin, increased LDH, hemoglobin in urine
38
Findings in extravascular hemolysis
Increased LDH and increased unconjugated bilirubin
39
How do you calculate corrected reticulocyte count?
(Hct / 45) x [Retic Count]. If polychromasia present, divide result by 2
40
What is the main regulator of iron in the body?
Hepcidin
41
Major causes of aplastic anemia
Benzene, chloramphenicol, alkylating agents, antimetabolites, parvo B19, EBV, HIV, HCV, Fanconis anemia, Immune mediated (often follows acute hepatitis)
42
Fatigue, malaise, pallor, purpura, mucosal bleeding, petechiae, infection
Aplastic anemia
43
What GI related effect does hemolytic anemia predispose to?
Pigmented gallstones
44
What test would you run (besides a CBC) if you suspect spherocytosis and what would be the result?
Osmotic fragility. RBCs will lyse in hypotonic saline
45
Treatment for hereditary spherocytosis
Splenectomy
46
Genetics of G6PD deficiency
X-linked
47
Back pain with hemoglobinuria a few days later. RBCs with heinz bodies and bite cells
G6PD deficiency
48
Cause of intrinsic hemolytic normocytic anemia in newborn (and most common associated finding)
Pyruvate kinase deficiency. Will find splenic hypertrophy from increased work
49
What substitution gives HbC?
Glutamic acid to lysine at position 6
50
Labs and complications of PNH
Increased urine hemosiderin. Complications - thrombosis
51
What substitution causes HbS?
Glutamic acid for valine at position 6
52
X-ray findings of sickle cell anemia
Crew cut
53
What is the immediate effect of an HbS mutation?
Hydrophobic interactions among hemoglobin molecules with HbS are altered
54
What causes autosplenectomy in sickle cell patients?
Vascular occlusion in the spleen
55
Most common complications of sickle cell related to microorganisms
Aplastic crisis (parvo B19) and osteomyelitis (salmonella, followed by s aureus and e coli)
56
How do children with sickle cell often present?
Dactylitis (painful swelling of the hand)
57
How would kidney problems in a sickle cell patient present
Either rapid onset hematuria (renal papillary necrosis) or microhematuria (medullary infarcts)
58
Treatment for sickle cell and how it helps
Hydroxyurea increases HbF. Give oxygen in crises. Last resort is bone marrow transplantation
59
Put the following in order of how far they travel on electrophoresis: HbA, HbC, HbS
(Least far to farthest) HbC, HbS, HbA
60
What composes warm agglutinins and what conditions are they seen in?
IgG. SLE, CLL, alpha-methyldopa and other drugs
61
What composes cold agglutinins and in what conditions are they seen
IgM. CLL, Mycoplasma pneumonia, infectious mono
62
Conditions in which microangiopathic anemia is seen
DIC, TTP-HUS, SLE, malignant hypertension. Will see schistocytes
63
Iron studies in pregnancy/OCP use
Serum iron nl, Transferrin up, Ferritin nl, Transferrin sat down
64
Iron findings in lead poisoning
Serum iron up, transferrin down, ferritin nl, transferrin sat up
65
What gene is mutation in PNH?
PIG-A (a GPI anchor)
66
In what condition will a CD55/CD59 deficiency be seen?
PNH (GPI anchor is necessary for CD55/59 attachment)
67
Hemolytic anemia, hypercoagulability, decreased blood counts
Suspect PNH
68
Headache, memory loss, demyelination
Lead poisoning (adult)
69
Defect in AIP
Porphobilinogen deaminase (aka uroporphyrinogen-I-synthase)
70
What is the rate limiting step in heme synthesis?
ALA synthase (first step). Defective in x-linked sideroblastic anemia
71
Painful abdomen, red-wine colored urine, polyneuropathy, psychologic disturbances, recent medication change.
AIP
72
What is the treatment for AIP?
Glucose and heme (they inhibit ALA synthase)
73
Defect in porphyria cutanea tarda
Uroporphyrinogen decarboxylase
74
Blistering cutaneous photosensitivity
Porphyria cutanea tarda (the most common porphyria)
75
List the substance that accumulates in each of the following - lead poisoning, AIP, porhyria cutanea tarda
Lead poisoning - protoporhyrin (in blood), AIP - porphobilinogen, ALA uroporphyrin (in urine), PCT - uroporphyrin (tea-colored urine)
76
Defect and genetics in Hemophilia A and B
X-recessive. A - 8, B - 9
77
Bleeding studies in hemophilia A and B
Increased PTT, normal PT, normal bleeding time
78
Defect and labs in Bernard-Soulier disease
Defect in platelet plug formation due to decreased GP1b (platelets cant bind vWF). Decreased platelet count, increased bleeding time
79
Defect and labs in Glanzmanns thrombasthenia
Decreased GpIIb/IIIa leads to defect in platelet-to-platelet aggregation. No change in platelet count, increased BT
80
Defect and labs in ITP
Anti-GPIIb/IIIa antibodies (platelet-Ab complex consumed by splenic macrophages). Decreased platelet count, increased bleeding time, increased megakaryocytes
81
Defect and labs in TTP
Deficiency of ADMTS13 leads to decreased degradation of vWF multimers (increased platelet aggregation and thrombosis). Low platelet count, high BT, schistocytes, high LDH
82
Neurologic and renal symptoms, fever, thrombocytopenia, microangiopathic hemolytic anemia
TTP
83
What bleeding abnormalities would be found in patients who have missed their dialysis a while and why?
Very long BT with normal platelet count, PT, and PTT. Uremia causes qualitative platelet d/o
84
vWF disease primarily affects binding of what to what?
Platelets to collagen (due to decreased levels of vWF)
85
Treatment for vWF disease and why
DDAVP. Releases vWF stored in endothelium
86
Labs in vWF disease
PC normal, BT high, PT normal, PTT normal or high
87
Labs in DIC
PC low, BT high, PT high, PTT high
88
Causes of DIC (7)
Sepsis, Trauma, Obstetric complications, acute Pancreatitis, Malignancy, Nephrotic syndrome, Transfusion
89
What is the most common cause of inherited hypercoagulability and how does the defect cause a problem?
Factor V Leiden. It cannot be degraded by protien C
90
What deficiency increases the chance of thrombotic skin necrosis after warfarin administration?
Protein C or S deficiency
91
How do you distinguish leukemia from leukemoid reaction?
High leukocyte alkaline phosphatase in leukemoid reaction
92
Which lymphoma is a localized single group of nodes with contiguous spread?
Hodgkins
93
Which lymphoma includes B symptoms most often
Hodgkins
94
Which lymphoma involves noncontiguous spread?
NHL
95
What is the relationship of Reed-Sternberg cell presence to diagnosis of Hodgkins?
Necessary but not sufficient
96
List the types of Hodgkins lymphoma from best prognosis (also most common) to worst prognosis (also least common)
Nodular sclerosing (most common, best prognosis), Mixed cellularity, Lymphocyte predominant, Lymphocyte depleted (least common, worst prognosis)
97
Starry sky appearance
Burkitts lymphoma. Due to lymphocytes interspersed with macrophages
98
What is the most common NHL and in whom does it usually occur?
Diffuse large B-cell. Usually older adults, but 20 percent in children
99
Mantle cell lymphoma marker and epidemiology
Older males, CD5 positive
100
What parts of the world are most affected by adult t-cell lymphoma and what is the causal agent?
HTLV-1. Japan, West Africa, Caribbean
101
What is the marker with mycosis fungoides/Sezary and how does it present?
CD4+. May present with cutaneous patches/nodules
102
Hypercalcemia, constipation, renal insufficiency, anemia, fatigue, back pain
Multiple myeloma (will also see lytic bone lesions)
103
What will you find in the kidney with multiple myeloma?
Atrophic tubules and eosinophilic casts
104
Bence Jones protein
Ig light chains in the urine. Usually have a Kappa-Kappa configuration
105
Markers in ALL
CALLA and TdT+
106
Mediastinal mass causing respiratory symptoms and SVC syndrome in a child
Consider ALL
107
What yields a better prognosis in ALL?
t(12,21)
108
What lymphoma and leukemia are the same disease and what is the difference between them?
Small Lymphocytic Lymphoma and CLL. CLL has increased peripheral blood lymphocytosis
109
Marker for hairy cell leukemia
TRAP
110
Auer rods
AML (common APL which is M3). Release leads to DIC
111
Treatment for APL (AML M3)
ATRA (vitamin A) induces differentiation of myeloblasts
112
CML translocation (give chrosomes and genes)
t(9,22). BCR-ABL
113
Burkitts translocation (give chrosomes and genes)
t(8,14). C-Myc activation
114
Follicular lymphoma translocation (give chrosomes and genes)
t(14,18). BCL-2 Activation
115
APL (AML M3) translocation (give chrosomes and genes)
t(15,17)
116
Ewings sarcoma translocation (give chrosomes and genes)
t(11,22)
117
Mantle cell lymphoma translocation (give chrosomes and genes)
t(11,14)
118
Markers in Langerhans cell histiocytosis (LCH)
S-100 and CD1a
119
What are JAK2 mutations associated with?
Chronic myeloproliferative disorders
120
What types of cells are increased in polycythemia vera?
RBCs, WBCs and platelets
121
Causes of ectopic erythropoietin (5)
RCC, Wilms tumor, cyst, HCC, hydronephrosis
122
Enoxaparin
Low molecular weight heparin. Act more on Xa, better bioavability, 2-4x longer half life. No monitoring necessary but not easily reversible
123
How does HIT work?
Heparin binds platelet factor IV causing antibody production which binds and activates platelets
124
Lepirudin and Bivalirudin
Direct thrombin inhibitors
125
Which one crosses the placenta, heparin or warfarin?
Warfarin. (Just remember that heparin is natural to the body, so it cant cause problems in pregnancy)
126
Fondaparineux
Pentasaccharide Xa inhibitor
127
Streptokinase
Thrombolytic
128
APSAC (anistreplase)
Thrombolytic
129
What change in the platelet count do thrombolytics cause?
None
130
What do you treat thrombolytic toxicity with?
Aminocaproic acid (an inhibitor of fibrinolysis)
131
What effect does aspirin have on blood studies?
Increased BT, no change in PT or PTT
132
Clopidogrel and Ticlopidine
Irreversibly block ADP receptors and inhibit platelet aggregation. Prevent IIb/IIIa expression.
133
What hematologic drug has a side effect that may present with fever and mouth ulcers?
Ticlopidine (neutropenia)
134
Cilostazol and dipyridamole
PDE III inhibitor (increased cAMP in platelets inhibits aggregation). Also vasodilate
135
Abciximab
Monoclonal antibody to IIb/IIIa receptor
136
Anticancer drugs acting on the S phase
Antimetabolites and etoposide
137
Anticancer drugs acting on the G2 phase
Etoposide and Bleomycin
138
Anticancer drugs acting on the M phase
Vinca alkaloids and taxols
139
What do you give to reverse methotrexate effects?
Leucovorin
140
What do you give to reverse 5-FU effects?
Thymidine (not leucovorin)
141
Cytarabine (ara-C)
Pyrimidine analog (inhibits DNA pol)
142
Dactinomycin
Intercalates DNA. Use in childhood tumors
143
Doxorubicin and daunorubicin
Generates free radicals, intercalates DNA. Use in Hodgkins. Cardiotoxicity (prevent with dexrazoxane), alopecia
144
Bleomycin
Free radical formation, DNA breaks. Pulmonary fibrosis, skin changes
145
Etoposide, teniposide
Inhibits topoisomerase II (causes DNA degradation). Myelosuppression, GI irritation, alopecia
146
Cyclophosphamide and ifosfamide
X-link DNA. Bioactivation by liver. Prevent hemorrhagic cystitis with mesna (binds metabolite)
147
Carmustine, lomustine, semustine, streptozocin
Alkylating agents. GBM. Dizziness, ataxia
148
Busulfan
Alkylating agent. CML. Pulmonary fibrosis, hyperpigmentation
149
Vincristine and Vinblastine
Block MT polymerization. Neurotoxic and paralytic ileus (vincristine), myelosuppression (vinblastine)
150
Paclitaxel (and other taxols)
Hyperstabilize MTs. Ovarian and breast carcinomas. Myelosuppression and hypersensitivity
151
Cisplastin, carboplatin
Alkylating-like agents. Cross link DNA. Nephrotoxic (prevent with amifostine), acoustic nerve damage, chloride diuresis
152
What is the most commonly used glucocorticoid in cancer chemotherapy
Prednisone (may induce apoptosis)
153
Tamoxifen and raloxifene
SERMs. Antagonists in breast and agonists in bone. May increase risk of endometrial ca (tamoxifen)
154
Trastuzumab
Antibody to Her-2. Cardiotoxicity
155
Imatinib
BCR-ABL inhibitor. Fluid retention
156
Most common chemotherapy causing cardiotoxicity
Doxorubicin
157
Most common chemotherapy causing myelosuppression
5-FU, 6-MP and Methotrexate
158
Aput tumors
S-100 positive. Melanoma, small cell of lung, bronchial carcinoid, carcinoid tumor, neuroblastoma
159
Young girl with necrotic mass coming out of her vagina. Vimentin and keratin negative, desmin positive.
Embryonal rhabdomyosarcoma (most common sarcoma of children)
160
What type of tumor tends to be found in the midline?
Teratomas
161
Most common site for lymphomas not in a lymph node
Stomach (H pylori)
162
Most common lymphoma
Follicular B cell
163
What is the presentation of hydatidiform moles and when do they present?
First trimester, signs of preeclampsia (HTN, proteinuria, edema)
164
Which type of hydatidiform mole can progress to cancer and what type of cancer?
Complete (46XX), choriocarcinoma. Partial (69 chromosomes) does not progress to cancer
165
Which vessel in the fetus has the highest O2 concentration?
Umbilical vein
166
What is seen in a hydatidiform mole that is not seen in a choriocarcinoma?
Chorionic villus
167
What hormones does the synctiotrophoblast (or a hydatidiform mole or choriocarcinoma) secrete?
B-hCG and hPL
168
Choristoma
Heterotopic tissue (i.e. pancreatic tissue in the GI tract)
169
How many doubling times does it take to get a tumor that can be detected clinically?
About 30 doublings
170
What types of cancer tend to spread to lymph nodes before going hematogenous?
Carcinomas (sarcomas can go directly hematogenous)
171
What carcinoma breaks the rule and goes directly hematogenous (without stopping in a lymph node first)?
Follicular carcinoma of the thyroid
172
In what organ is primary cancer more common than metastasis?
Kidney (renal adenocarcinoma)
173
What lab abnormality will likely be seen in metastasized prostate cancer?
Increased alkaline phosphate (because prostate carcinoma is blastic to bone)
174
What is seen on EM of a vascular malignancy?
Wibble palad bodies (have vWF in them)
175
Steps in oncogenesis (and define each)
Initiation (mutation), Promotion (multiple copies of mutation are made), Progression (sub-specialization)
176
What type of mutation is responsible for loss of function in all TS genes?
Point mutation
177
Why is hepatocellular carcinoma common in Asia?
Because hepatitis B and aflatoxin (aspergillus) are common
178
What is the cause of the rapidly increasing incidence of primary CNS lymphoma?
HIV
179
Associations with UVA and UVB light
UVA - black light (contributes to skin cancer indirectly, less dangerous), UVB - skin cancers (basal cell, squamous cell, melanoma), UVB - thymidine dimers
180
What metal is associated with skin cancer?
Arsenic
181
Most common cause of white eye reflex
Congenital cataract (CMV, rubella, corticosteroids, Cushings). Rb is notable, but less common
182
What is the basic rule for BCC and SCC?
Upper lip and above is BCC, lower lip and down is SCC
183
What is the only bacterium associated with cancer?
H pylori
184
What is the general rule for colon cancer symptoms?
Left side obstructs, right side bleeds (watch for anemia with right side)
185
What can metastasize to virchows node besides gastric cancer?
Pancreatic
186
Trousseaus sign
Superficial migratory thrombophlebitis due to carcinoma of the head of the pancreas
187
Two common hematologic findings in cancer patients
Hypercoagulability and thrombocytosis
188
Most common cause of fever in cancer patients
Gram negative infection (e coli from indwelling catheter, pseudomonas from respirator, also s aureus from catheter even though its gram positive)
189
What is the most common paraneoplastic syndrome?
Hypercalcemia
190
Cancers that PTHrP
Squamous of the lung and RCC
191
What are two skin signs that if they show up quickly might signal cancer, and which cancer do they signal?
Acanthosis nigricans and seborrheic keratosis. Quick development may signal gastroadenocarcinoma
192
What collagen vascular disease is associated with cancer and which cancers?
Dermatomyositis - leukemia, lymphoma and lung cancer. Can get patches on knuckles (goltrins patches)
193
What endocarditis is associated with cancer and which cancers?
Marantic (nonbacterial thrombotic) endocarditis. Mucuous producing cancers (eg colon). Be careful, they can embolize
194
What tumor can convert calcitonin to amyloid?
Medullary carcinoma of the thyroid
195
What tumors is AFP associated with?
Yolk sac tumor and HCC
196
How can CEA (marker for colon cancer) cause problems outside the colon?
CEA-Ag complexes can deposit in the kidney and cause diffuse membranous glumerulonephritis (a nephrotic syndrome)
197
Most common benign and malignant primary CNS tumors in kids
Benign - cerebellar cystic astrocytoma (most common overall), malignant - medulloblastoma
198
Most common cancers in men and women respectively
Men - prostate, lung, colon. Women - breast, lung, colon
199
Most common infection transmitted by accidental needle stick in the hospital
Hepatitis B
200
How long does it take after anemia develops to get an elevated reticulocyte count?
5-7 days
201
What is the cutoff for an expected reticulocyte count in anemia?
Corrected retic count should be 3 percent or greater
202
What is the most common cause for failure of the Hb and Hct to go up sufficiently after transfusion?
GI bleed (which is most common cause of anemia worldwide)
203
Where are iron, folate and B12 absorbed respectively?
Iron - Duodenum, Folate - jejunum, B12 - terminal ileum
204
What is the most common cause of malabsorption and what areas does it affect?
Celiac sprue. Duodenum and jejunum
205
What finding on a blood smear is an important marker for alcoholism?
Target cells (due to altered cholesterol concentration)
206
What is the relationship between transferrin and TIBC?
They are the same
207
What determines the number of cell divisions an RBC precursor undergoes when developing in the marrow?
Hb concentration
208
4 globins and the 3 normal hemoglobins
Globins - A, B, D, G. HbA is 2A2B, HbA2 is 2A2D, HbF is 2A2G
209
Whats the best way to distinguish between IDA and anemia of chronic disease?
ACD - high ferritin levels, IDA - high TIBC (transferrin)
210
What is the inhibitory neurotransmitter in the spinal cord?
Glycine
211
3 causes of sideroblastic anemias
Alcohol, Vitamin B6 deficiency, Lead poisoning
212
EM findings in alcoholism
Megamitochondria (alcohol is an uncoupling agent and screws up mitochondria)
213
What causes a ringed sideroblast?
Iron that enters the mitochondria but cant get out (because its not properly assembled into heme)
214
Primary populations for alpha thalassemia
Far easterners and blacks
215
What will be the results of Hb electrophoresis in alpha thalassemia?
Normal. Alpha globin is required in all the normal hemoglobins (HbA, HbA2 and HbF) so they are all equally decreased
216
Why is the rate of choriocarcinoma high in the far east?
Because the higher incidence of alpha-thal leads to spontaneous abortion (Hb Barts) which predisposes to choriocarcinoma
217
Treatment for alpha thalassemia
None. Do not give iron
218
Populations in which beta thal is common
Blacks, greeks, italians
219
What will you see on Hb electrophoresis in beta thal?
Decrease in HbA, increase in HbA2 and HbF
220
Most common cause of iron deficiency anemia in a newborn
Bleeding meckels diverticulum
221
What causes cerebral edema in lead poisoning?
Buildup of delta-lemavinylinic acid
222
Common lead poisoning scenarios
Child - eating paint. Adults - automobile shop (batteries), moonshine (made in old radiator), pottery painter (lead based paint)
223
Iron studies in alpha and beta thal
Serum iron - normal, TIBC - high, Saturation - high, Ferritin - high
224
What are the two main jobs of B12?
Transfer methyl group from folate to homocysteine (to make methionine) and helping with odd chain FA metabolism
225
How does B12 deficiency lead to neurologic symptoms?
Succinyl CoA builds up (failure of odd chain FA metabolism) and screws up myelin
226
What drug inhibits intestinal conjugase and what is the effect of this?
Phenytoin. This significantly reduces folate absorption (conjugase has to turn polyglutamate to monoglutamate folate)
227
What two substances inhibit folate absorption?
OCPs and alcohol
228
How many lobes does a PMN have to have to be called hypersegmented?
5 or more
229
Drugs that cause aplastic anemia
Chloramphenical, indomethacin, phenylbutazone, thyroid drugs
230
Do you get hemoglobinuria in intravascular hemolysis, extravascular hemolysis, or both?
Intravascular only
231
Which type of hemolysis more typically produces jaundice, intravascular or extravascular?
Extravascular
232
Most common causes of intrinsic hemolysis
MAD. Membrane defect (spherocytosis, PNH), Abnormal Hb (SC), Deficiency of enzyme (G6PD)
233
In sickle cell disease, what percentage of a cells hemoglobin has to be sickled for the cell to sickle?
60 percent
234
What is the most common cause of death in a child with sickle cell disease
Strep pneumo sepsis
235
At what age does sickle cell disease typically present?
6-9 months
236
Two x linked recessive enzyme deficiences
G6PD and Lesch-Nyhan
237
What damages the RBCs in G6PD deficiency and what blood smear finding does it cause?
Peroxide damages hemoglobin, leading to Heinz bodies (Hb clumped together)
238
What populations is G6PD typically seen in?
Same populations as beta thal - blacks, Greeks, Italians
239
Two drugs most commonly used in G6PD questions
Primaquine and dapsone
240
Which is more common, warm or cold agglutinins and what is the most common cause of it?
Warm. Most common cause is lupus
241
Hypersensitivity reactions to penicillin
Rash - Type 1. Hemolytic anemia - Type 2
242
How does methyldopa lead to hemolytic anemia?
It alters Rh antigens on RBCs and we end up making antibodies against our own Rh antigens
243
How does quinidine lead to hemolytic anemia?
It forms immune complexes with IgM
244
Three main drug induced autoimmune hemolytic anemias and the hypersensitivity type for each
PCN - type 2 (but rash is type 1), Methyldopa - type 2, Quinidine - type 3
245
What is the most common cause of chronic intravascular hemolysis
Aortic stenosis
246
What infection in kids can lead to such high WBC counts that we get concerned it might be ALL?
Pertussis. Viral infections can also do it
247
What do we associated with atypical lymphocytes?
Mononucleosis - EBV
248
What drug is associated with atypical lymphocytes?
Phenytoin
249
What receptor does EBV use to infect B cells?
CD21
250
Generalized painful lymphadenopathy, exudative tonsilitis, very high transaminases, spleen enlargement
EBV mono. Also get jaundice sometimes and spleen can rupture (no contact sports)
251
What does the heterophile antibody test use and what does it test for?
Uses anti-horse or anti-sheep RBC antibodies to test for EBV mono
252
What helminth infection does not cause eosinophilia?
Adult ascariasis (because they stick to the intestine and do not invade)
253
Which leukemia is also a myeloproliferative disease?
CML
254
Most common complication of polycythemia rubivera
Thrombosis (most commonly Budd-Chiari)
255
4 Hs of polycythemia rubivera
Hyperviscosity, Hypovolemia, Histaminemia, Hyperuricemia
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A patient takes a shower and gets itchy all over his or her body
Polycythemia rubivera (the increased numbers of mast cells and basophils hang out in skin and degranulate more easily)
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What distinguishes between acute and chronic leukemia
Blasts less than 30 percent is chronic, greater than 30 percent is acute
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Leukemia in ages 0-14
ALL
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Leukemia in ages 15-39
AML
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Leukemia in ages 40-59
AML or CML (separate with bone marrow looking for blasts or philadelphia chromosome)
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Leukemia in 60 and over
CLL
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What stain can tell the difference between mature neutrophils and neoplastic neutrophils
Leukocyte Alkaline Phosphatase (LAP). Mature will take it up, neoplastic will not
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Kid with sternal tenderness, fever, generalized nontender lymphadenopathy, hepatosplenomegaly, normocytic anemia, WBC count 50,000
ALL. Most commonly CD10+, CALLA+. May be associated with Downs
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Elderly patient, smudge cells, normocytic anemia, hypogammaglobulinemia
CLL. High risk of infection (most common cause of death in CLL)
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What two tissues are resistant to invasion by cancer cells?
Cartilage and elastic tissue
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Langerhans cell histiocytosis looks like a tennis raquet on EM. What else has this look on EM?
Clostridium tetani spores
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Where in the lymph nodes are macrophages usually found?
In the sinuses
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Reed sternberg cells have an Owls eye appearance. What else has this appearance?
Giardia, CMV, aschoff nodules in rheumatic fever
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Woman with mass in anterior mediastinum and neck. Fatigue, night sweats, weight loss.
Nodular Sclerosing Hodgkins. Look for RS cells, be sure to rule out TB if she has a cough
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What do pts with Pompe disease typically die of?
Cardiac failure due to excess deposition of normal glycogen in the heart
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What do OCPs do that makes them thrombogenic
Increase synthesis of factors 5 and 8, increase synthesis of fibrinogen, inhibit antithrombin 3
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How does smoking lead to thrombogenesis?
Damages endothelial cells (exposing collagen to the clotting system)
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Where is vWF made?
Megakaryocytes and endothelial cells
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What are the effects of PGI2 and TXA2 respectively on blood vessel diameter?
PGI2 is a vasodilator, TXA2 is a vasoconstrictor
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What is the main vasoconstrictor in Prinzmetals angina?
TXA2
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Both platelets and mast cells when activated release a preformed chemical then start making chemicals. What are these substances (give the preformed and manufactured for each platelets and mast cells)?
Platelets - preformed is ADP (and others), manufactured is TxA2. Mast cells - preformed is histamine (and 5HT and eosinophil chemotactic factor), manufactured is PGs and leukotrienes
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Are petechia, echymoses, and epistaxis more characteristic of platelet or coagulation abnormalities?
Platelet
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What procedure imposes the greatest hemostatic stress on the body?
Wisdom tooth extraction (good question to screen for coagulation disorders)
279
What is the test for vWF disease?
Ristocetin cofactor assay (ristocetin wont cause platelets to clot if missing vWF)
280
Factors of the common final pathway (in order)
10, 5, 2, 1
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Factors of the intrinsic pathway (in order)
12, 11, 9, 8. Then common final pathway (10, 5, 2, 1)
282
Best test for DIC
D-dimer. Next best is fibrin split products
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How can you tell the difference between petechia and spider angioma (telangiectasia) on physical exam?
Petechia do not blanch but spiger angiomas will (because its an AV fistula)
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Kid with epistaxis and spots that do not blanch. Low platelet count
ITP
285
Treatment for ITP
Cotricosteroids if severe, if not severe just leave it alone
286
Two main causes of HUS
E coli O157H7 and Shigella toxin
287
Main differences between vWF disease and Hemophilia A
1) Genetics (hemophilia A is XR and vWF is AD), 2) Number of deficiencies (hemophilia A its only 8 anticoagulant, vWF it is 8 Ag, 8 anticoagulant, and vWF), 3) vWF includes symptoms of platelet dysfunction
288
Why is vWF disease often underdiagnosed in women?
Because OCPs cause increased synthesis of 8 Ag, 8 anticoagulant and vWF (the things deficient in vWF disease), which can mask the disease
289
What is the difference between anti-AB and anti-A/anti-B?
Anti-AB is IgG whereas anti-A and anti-B are IgM
290
Diseases associated with AB blood groups
A - gastric cancer, O - duodenal ulcer
291
What antigen is missing in the black population which makes them less likely to get a malaria and which malaria?
Duffy antigen, reduces chances of getting plasmodium vivax
292
G6PD, thalassemias, and SCD protect from which malaria?
Plasmodium falciparum
293
What is the most common antibody in the US?
Anti-CMV
294
What is the most common infection transmitted by blood transfusion?
CMV
295
What is the most common type of hepatitis picked up from transfusion?
Hep C
296
What causes febrile transfusion reactions?
HLA antibodies against leukocytes in donor blood
297
Who is most at risk for febrile reaction with transfusion?
1) Patients who have been transfused before many times. 2) Women (may have picked up HLA Abs from fetal-maternal bleed)
298
Which Ig is the most potent complement activator?
IgM. It will activate straight C1-C9 and you will get a MAC. Eg. hemolytic transfusion reactions (if wrong blood type given) happen very fast due to IgM
299
What cells are responsible for delayed hemolytic transfusion reactions?
Memory B cells. Antibodies arent detected on cross-match because the memory B cells are dormant. But once they see an Ag on the transfused blood they start making Ab again
300
Woman with a difficult delivery (abruptio placenta) one week ago returns with jaundice, anemia, and uncojugated hyperbilirubinemia
Delayed hemolytic transfusion reaction (assuming she was transfused)
301
If someone has serious surgery and returns with jaundice how can you separate delayed hemolytic transfusion reaction from halothane and from hepatitis?
Delayed hemolytic transfusion - about 1 week, halothane - over a week, hepatitis - 6 to 8 weeks
302
What type of hypersensitivity is involved in delayed hemolytic transfusion reactions?
Type 2
303
Most common cause of jaundice in first 24 hours for a newborn
ABO incompatibility (physiologic jaundice of newborn starts at day 3)
304
If a baby has ABO incompatability, what blood group must the mom be?
O (because anti-AB is the only one that is IgG and thus the only one that can cross the placenta)
305
Which leads to a more serious hemolytic anemia, ABO incompatibility or Rh incompatibility?
Rh
306
What other condition protects against Rh sensitization and how?
ABO incompatability. If fetal blood is both Rh and ABO incompatible and there is maternal fetal bleed at birth the anti-A and anti-B IgM will destroy cells so fast there wont be time for anti-Rh sensitization
