Uworld: 5-19

Front 1

Chemotherapy associated with tingling of hands and feet

Back 1

Vincristine (or any of vinca alkaloids)

Front 2

Draw the cancer cell cycle and describe the events that occur and where certain drugs act.

Back 2

Front 3

Disseminated Intravascular Coagulopathy:
Pathophys

Back 3

Complication of gram-negative bacterial sepsis, acute pancreatitis, and burn injury

In gram-neg sepsis, results from activation of coagulation cascade by bacterial endotoxina, causing formation of microemboli

Lab tests will show prolonged PT, PTT, dec'd fibrinogen, factors V and VIII

Front 4

Describe the effect of epinephrine, phenylephrine, and dopamine (low dose) on:
SBP
DBP
HR
Contractility
Renal Blood Flow

Back 4

Remember: D1 receptors in renal and mesenteric vasculature cause vasodilation and inc'd blood flow.

Front 5

How does low dose dopamine differ in its effects from high dose dopamine?

Back 5

Low Dose: Only activates beta-1 and D1 receptors (D1 inc vasodilation to kidneys)

High Dose: Act on alpha-1 receptors-->can cause generalized vasoconstriction!

Front 6

19 year-old female
Recurrent otitis media
s/p MVA
Blood transfusion with O negative PRBCs
Patient develops diffuse itching, rash, bronchospasm

Diagnosis, Pathophys
What happened?

Back 6

Patient has selective IgA deficiency; thought to occur due to failure of B cells to switch from IgM to IgA. Infections due to encapsulated bacteria (SHiN). May also see recurrent GI infections.

Patients with selective IgA deficiency often form IgG ab's directed against IgA (anti-IgA antibodies); when transfused w/blood or blood products containing small amts of IgA, pts may develop ANAPHYLAXIS.

Front 7

Carbon tetracholoride poisoning:
Molecular pathophys

Back 7

CCl4 oxidized by P450 of liver
Becomes free radical CCl3 and induces lipid degradation and H2O2 formation (LIPID PEROXIDATION)

Results in hepatocyte necrosis

Front 8

What are the GI and CNS effects of somatostatin?

Back 8

CNS: dec'd release of GH
GI: dec'd release of CCK (***gallstone alert***), glucagon, insulin, gastrin

Front 9

What role does metalloproteinase play in determining the likelihood that atheroma would rupture?

Back 9

Plaque stability depends on mechanical strength of fibrous cap.

Inflammatory macrophages in intima may reduce plaque stability by secreting metalloproteinases, which degrade collagen (remodeling of fibrous cap)

Front 10

23 year-old male
2 day history of fever, HA, confusion
Bilateral hemorrhagic necrosis of temporal lobes

Diagnosis
What other symptoms would you expect ot see?

Back 10

HSV-1 encephalitis

Would also see aphasia, olfactory hallucination, and personality changes (amygdala involvement)

Front 11

Endogenous compound that binds mu receptors after noxious stimuli

Back 11

beta-endorphin

Hint 11

A

Front 12

What compounds share a molecular origin with beta-endorphin?

Back 12

Beta-endorphin is derived from POMC, so it's also related to ACTH and MSH

Front 13

2 year-old male
Urine turns black on way to laboratory

Diagnosis
Biochemical pathophys

Back 13

Alkaptonuria
Accumulation of homogentisic acid in urine imparts black color after undergoing oxidation.

Front 14

What would be the effect of dobutamine infusion on a pressure-volume loop?

Back 14

Front 15

What would be the effect of clamping the abdominal aorta on a pressure-volume loop?

Back 15

Front 16

What would be the effect of loss of contracting myocardial mass on a pressure-volume loop?

Back 16

Front 17

What would be the effect of normal saline infusion on a pressure-volume loop?

Back 17

Inc'd ventricular preload. Rightward shift of ventricular filling portion of graph indicates a larger than normal volume is being placed into ventricle during diastole. Can occur during any state of fluid overload (renal failure, CHF, infusion of IV fluids)

Front 18

Lithium:
Side Effects
What tests must be ordered periodically?

Back 18

Hypothyroidism
Nephrogenic Diabetes Insipidus

Need to order TSH and renal function (lithium is exclusively excreted by the kidneys!)

Also it's a teratogen and can cause Ebstein's anomaly.

Front 19

2 year-old male
Cherry red macular spot
Foamy histiocytes

Back 19

Sphingomyelinase deficiency (Niemann-Pick)

Front 20

Temporal bone fracture

Back 20

Epidural hematoma due to tear of Middle Meningeal Artery

Front 21

Describe the following for epidural hematomas, subdural hematomas, and subarachnoid hemorrhages:
Blood vessel involved
Location of bleeding (between which structures)
Clinical manifestation
Presentation on CT scan

Back 21

Front 22

Describe the steps required for eosinophils to be targeted against schistosomiasis.

Back 22

When parasite enters bloodstream, it is bound by free IgE
Resultant Ag-Ab complex binds IgE Fc receptor (on heavy chain) of eosiniophil
On binding, eosinophil releases MBP and other granules to destroy parasite

This is an example of antigen-dependent cellular cytotoxicity.

Front 23

What cells employ antibody-dependent cellular cytotoxicity?

Back 23

Eosinophils
Macrophages
NK Cells

Front 24

How does eosinophils regulate Type I hypersensitivity reaction?

Back 24

Eosinophilic granules contain histaminase, an enzyme that degrades histamine (helps reduce severity of atopic symptoms).

Also contain leukotrienes and peroxidases that facilitate inflammn.

Front 25

What steps are required for immediate hypersensitivity reactions?

Back 25

Antigen/Allergen-binding of more than one membrane-bound IgE (antibody crosslinking)

This stimulates degranulation of MAST CELLS and BASOPHILS, which release histamine, bradykinin.

Front 26

Which staph is associated with prosthetic valves and joints?

Back 26

S. epidermidis

Front 27

This staph strain is sensitive to novobiocin.

Back 27

S. epidermidis

Front 28

Pharyngitis
Conjunctivitis
Cervical LAD

Cause

Back 28

Adenovirus

Front 29

Croup

Virus and class

Back 29

Parainfluenza of paramyxoviridae

Front 30

Caliciviridae:
Example and its presentation

Back 30

Norwalk virus--epidemic outbreaks of viral gastroenteritis

Front 31

Drunk driver starts lecturing against drunk driving.

Coping mechanism?

Back 31

Reaction formation

Front 32

When thinking about harming someone, patient is suddenly nice to that person.

Coping mechanism?

Back 32

Undoing

Front 33

Describe the following for epidural hematomas, subdural hematomas, and subarachnoid hemorrhages:
Blood vessel involved
Location of bleeding (between which structures)
Clinical manifestation
Presentation on CT scan

Back 33

Front 34

Describe the clotting cascade and include where certain anti-platelet drugs act.

Back 34

Note: ADP and TXA are released once platelets have become activated. They act to activate other platelets.

Front 35

28 year-old male
Experiences fever, muscle rigidity after major surgery
Skin is mottled

Diagnosis
Pathophys
Lab values
Treatment

Back 35

Malignant hyperthermia syndrome

Ryanodine receptors are calcium channels on surface of sarcoplasmic reticulum in skeletal muscle

They release small amts of calcium in cytoplasm of muscle fiber during contraction

Abnormal ryanodine receptors release large amounts of Ca after exposure to anesthetic. Excess free Ca2+ in cytoplasm of muscle fibers stimulates ATP-dependent uptake by sarcoplasmic reticulum.

Excessive consumption of ATP generates heat; loss of ATP along with high temperature induces muscle damage. Rhabdomyolysis leads to release of K+, myoglobin, and creatine kinase.

Treat with DANTROLENE to block ryanodine receptors and prevent release of Ca into cytoplasm.

Front 36

Back 36

Target cells:
Associated with liver disease, thalassemia, Fe def anemia

Front 37

alpha- vs beta-thalassemia:
Populations affected
Pathophys

Back 37

alpha-thalassemia: Southeast Asians
beta-thalassemia: Mediterranean

Mutations result in defective mRNA processing leading to deficiency of certain protein chains required for hemoglobin synthesis.

Beta-thalassemia minor is typically asyx.

Front 38

Hgb 10.0 mg/dL
MCV 70 fl
HbF 5%

Back 38

Microcytic anemia with elevated HbF-->Thalassemia

Front 39

What are the forms of amyloid deposits in the brain (in AD)?

Back 39

Amyloid deposits:
Senile plaques (core = beta-amyloid)

Amyloid angiopathy: damage media and adventitia of cerebral vessels; cause thickening of basal membrane, stenosis of lumen

Note that these can e seen in brains of healthy elderly individuals.

Front 40

What drug should be given after SAH?

Back 40

Calcium channel blockers

Namely nimodipine (cerebral selective drug)

Note: SAH is due to vasospasm, so due to an unknown mechanism, CCB helps.

Front 41

This nerve courses between the biceps and coracobrachialis.

Back 41

MCN

Front 42

This nerve courses between the flexor carpi ulnaris and flexor digitorum profundus.

Back 42

Ulnar

Front 43

This nerve courses between the digitorum superficilais and flexor digitorum profundus.

Back 43

Median

Front 44

This nerve courses between the olecranon and the medial epicondyle of the humerus.

Back 44

Ulnar

Front 45

This nerve courses between the supinator and head of the radius.

Back 45

Radial

Front 46

What are the categories of antimetabolites? Which drug goes in each category?

Drug of choice for CLL?
HCL?

Back 46

Front 47

This antimetabolite is resistant to degradation by adenosine deminase.

Back 47

Cladribine (drug of choice for Hairy Cell Luekemia)

Hint 47

Giardia

Front 48

Which organisms can cause infection with as few as 1 cell?

Back 48

Giardia lamblia
Entamoeba histolytica

Front 49

Which organisms can cause infection with as few as 10 cells?

Back 49

Shigella flexneri

Front 50

Which organisms can cause infection with as few as 500 organisms?

Back 50

Campylobacter jejuni

Front 51

45 year-old female
Point tenderness above scapular spine, lateral epicondyle, medial fat pad of knee, bilaterally

Diagnosis

Back 51

Fibromyalgia

Mech UNK, likely heightened pain sensitivity or pain misperception

Front 52

Morning stiffness of neck, shoulder, pelvic girdle
Weight loss
Fever
Elevated ESR

Back 52

Polymyalgia rheumatica

Front 53

What musculoskeletal disorder is associated with temporal arteritis?

Back 53

Polymyalgia rheumatica

Front 54

How does PTH increase bone resorption?

Back 54

Causes osteoblasts to increase production of RANK-ligand and Monocyte CSF (stimulate osteoclastic precursors to differentiate into bone-resorbing, mature osteoclasts)

Also decreases release of osteoprotegrin (decoy receptor for RANK0L)

Front 55

35 year-old male
Generalized motion restriction, shaking of righ thand
Admitted to hospital three weeks ago after hearing voices

Diagnosis
Treatment

Back 55

Was likely given a DA antagonist for psychosis-->drug-induced Parkinsonism

Tx: Ach-blocking drugs such as benztropine

Front 56

When are levodopa and bromocriptine contraindicated in treatment of Parksinson's?

Back 56

When it's drug-induced!

Drug-induced PD likely due to DA antagonists (bc of psychoses); giving Levodopa or Bromocriptine will increase DA activity and may precipitate psychosis.

Front 57

Why don't women lactate during pregnancy?

Back 57

high circulating levels of E and PG prevent lactogenesis (via PL) while also promoting breast growth.

Front 58

CEA

Back 58

colorectal cancers
pancreatic cancers

Front 59

CA 19-9

Back 59

Pancreatic cancer

Front 60

Serum-AFP

Back 60

HCC
Nonseminomatous germ cell tumor (Yolk cell tumor)

Front 61

CA-125

Back 61

Ovarian epithelial tumor

Front 62

What cells utilize bisphosphoglycerate mutase?
Why?

Back 62

Erythrocytes

Bigphosphoglycerate mutase converts 1,3-Bisphosphoglycerate to 2,-3-bisophosphoglycerate (2,3-DPG)

This enables RBCs to increase O2 delivery to peripheral tissues in presence of lower blood O2 [ ].

Produces no net ATP.

Remember: RBCs don't have mitochondria and can't regenerate energy from citric acid cycle. Use an alternate glycolytic pathway.

Front 63

What is Horner's syndrome?

Back 63

Ipsilateral ptosis, miosis, anhydrosis (lack of sweating)

Front 64

69 year-old male
Smoker
Recent hemoptysis
Weakness of right hand
Pain beneath right scapula and in right arm

Diagnosis
Pathophys

Back 64

Hemoptysis in elderly smoker-->Bronchogenic carcinoma

Tumor arises in SUPERIOR SULCUS and can invade multiple neck structures, causing:
ipsilateral Horner's (ptosis, anhydrosis, miosis)
Rib destruction
Atrophy of hand muscles
Pain in distribution of C8, T1, T2
Hand atrophy

Front 65

Tumor arising in superior sulcus

Back 65

Pancoast Tumor

Front 66

54 year-old male
Difficulty rising from a chair
Diagnosed with lung cancer
Increase in muscle response on repetitive motor nerve stimulation

Diagnosis
Pathophys

Back 66

Lambert-Eaton Syndrome:
Due to antibodies attacking pre-synaptic calcium channels

Front 67

Compare myasthenia gravis with Lambert-Eaton syndrome in terms of:
Symptoms
Associations/Risks
Pathophysiology
Tensilon test results
Nerve stimulation studies

Back 67

Note: Tensilon inhibits breakdown of ACh.

Front 68

Diagnosis
Complications

Back 68

Multiple linear, striated areas within medullary pyramids reminiscent of a paintbrush-->Medullary Sponge Kidney

Unknown mechanism, BUT patients are at risk of KIDNEY STONES.

Front 69

Diagnosis
Pathophys
Complications

Back 69

Myxomatous changes in media of large arteries = CYSTIC MEDIAL DEGENERATION

Note basket weave pattern of elastic fibers and separation of elastic and fibromuscular components by cleft-like spaces filled with ECM (arrow)

This is associated with Marfan's and predisposes patients to aortic aneurysm.

Front 70

Myxomatous changes of arteries

Back 70

Cystic medial degeneration-->AORTIC ANEURYSM (just like in Marfan's)

Front 71

Beginning with normal epithelium and ending with adenocarcinoma, list the steps and associated mutations in development of colon cancer.

Back 71

Normal epithelium
MUTATION TO APC
Early adenoma
MUTATION TO K-RAS (increasing size of polyp due to unregulated cell growth)
MUTATION TO P53 AND DCC
Adenocarcinoma (malignant transformation requires these two genes to be mutated!)

Front 72

26 year-old male
Pleuritic chest pain
Sharp pain in back and neck

What nerve allows for this?

Back 72

Phrenic

Front 73

Which leukotriene stimulates neutrophil migration?

Back 73

Leukotriene B4