Uworld: 5-13

Front 1

Provide a timeline for events between fertilization of an ovum and implantation.

When does beta-hCG become detectable?

Back 1

Zygote travels through isthmus and enters uterus as 2- to 8-cells embryo (or morula) on day 3-4 POST-ovulation

6 days post-ovulation: morula-->blastocyst freely floating in uterus

After implantation, beta-hCG secretion begins. This occurs between 8-11 days after ovulation.

Front 2

Back 2

Candida: budding yeasts with pseudohyphae

May mimic cryptococcus, but cryptococcus doesn't have hyphae/pseudhyphae

Front 3

Diagnosis

Back 3

Seborrheic keratosis

Front 4

Diagnosis

Back 4

Actinic keratoses

Front 5

Which vaccines covalently bind polysaccharides to toxoid?

Back 5

Strep pneumo
Neisseria meningitidis
H influenzae

(Encapsulated bacteria)

Can use diphtheria toxin, tetanus toxoid

Front 6

Skin lesion with central scale and sandpaper texture

Back 6

Actinic keratosis

Risk of SCC

Front 7

Skin lesion with stuck-on appearance, deeply pigmented

Back 7

Seborrheic Keratoses

Front 8

Define acanthosis

Back 8

Thickening of epidermis

Front 9

Rapidly progressive fever
Severe sore throat
Drooling
Stridor
Child

Diagnosis
Cause

Back 9

Epiglottitis due to H flu

Front 10

Lactase deficiency:
Diagnostics and their findings

Back 10

Osmotic diarrhea (inc'd stoom osmotic gap)

Increased breath hydrogen (bacterial fermentation of excess lactose produces SCFAs and excess hydrogen)

For above reason also see decreased stool pH on lactose challenge

Front 11

Which bronchus is more likely to become obstructed on aspiration?

Why?

Back 11

RIGHT MAIN BRONCHUS or its branches because bronchus is:
-shorter
-wider
-more vertical (straighter)

Than left bronchus

Front 12

Cystic fibrosis:
Diagnostics and findings
Include findings for mild CF

Back 12

Diagnosis by high sweat chloride concentrations

Mild mutations have normal sweat tests (sweat Cl- <60 mM/L)

Measure nasal transepithelial potential difference (between surface of resp epithelia and interstitial fluid):
-

Normally, CFTR secretes Cl- into lumen and inhibits sodium channel respomnsible for Na+ resorption

In CF:
There's absorption (rather than secretion) of Cl-
In addition to absorption (due to lack of inhibition) of Na+ (water then follows-->thicker mucus)

Front 13

73 year-old male
Cyanotic toe discoloration following coronary angioplasty
Elevated Serum Cr

Pathophys

Back 13

Angiography/angioplasty/AORTIC surgery-->cholesterol-containing debris pushed from larger arteries and lodged into smaller vessels

Results in ischemia; kidneys frequently involved

Will find cholesterol crystals (needle-shaped!) obstructing renal arterioles

Many recover from this.

Front 14

What is stool neutral fat?

Back 14

Triglyceride levels in poop

Front 15

How does pancreatectomy affect absorption of sugar in the GI tract?

Back 15

Pancreatic amylases, along with salivary and brush border amylases, required for degradation of polysaccharides into monosaccharides

Intestinal mucosa can't absorb polysaccharides

Will be able to absorb D-xylose, glucose, galactose (all monosaccharides!)

Front 16

Antibodies against small nuclear ribonucleoproteins

Back 16

anti-snRNPs = anti-Smith

Lupus

Front 17

Photosensitivity
Arthralgias
Skin rash

Back 17

SLE

Front 18

18 month-old
Fever
Rhinitis
Pharyngitis

Diagnosis
Cause

Back 18

URI

Rhinovirus
followed by Influenza virus

Front 19

Fever
Runny Nose
Sore Throat
Brassy Cough
Difficulty breathing

Diagnosis
Cause

Back 19

Child has developed laryngotracheobronchitis (croup) post-URI

Occurs when inflamed subglottic tissue obstructs upper airway; stridor!

Causes:
Paramyxoviruses;
more specifically:
-parainfluenza***
-RSV

Could also be influenza virus, adenovirus

Front 20

What is the effect of exogenous T3 on:
TSH
T3
Reverse T3
T4

Back 20

Elevated systemic T3 and T4 (via intracellular conversion to T3) cause negative feedback on TSH produciton/release.

T4 can be converted in peripheral tissues to more active T3 or inactive rT3.

T3 cannot be converted to rT3 or T3.

Exogenous T3 will decrease TSH, which will decrease rT3 and T4 levels. T3 levels will obviously rise.

Front 21

Patient undergoes total gastrectomy.

Supplementation required?

Back 21

Pt will require lifelong B12 due to poor B12 absorption that occurs w/IF deficiency.

Front 22

Role of Type I pneumocytes

Back 22

Mediate gas exchange

Front 23

Hematuria
Proteinuria
Urine RBC Casts
Hypercellular Glomeruli

Diagnosis
Other lab findings

Back 23

Post Strep GN

Other findings:
Elevated anti-Streptolysin O, anti-DNAse B, anti-catioionic proteinase (anti-strep Ab's)

Low C3 concentration

Front 24

Diagnosis

Back 24

Hypercellular glomeruli involving all lobules--result of luekocyte infiltration

PSGN

Front 25

Diagnosis
What is shown?

Back 25

PSGN
Starry sky appearance showing granular deposits of IgG and C3

Front 26

64 year-old female
Chronic knee pain and degenerative joint disease
Mild renal insufficiency with 1+ protein

Undergoes knee replacement and is now pain free
Renal function normal

What happened?
Histologic findings?

Back 26

Patient likely took NSAIDs.

NSAID-associated CHRONIC renal injury leads to PAPILLARY NECROSIS and CHRONIC INTERSTITIAL NEPHRITIS

Mild glomerular and vasc abnlts

Front 27

Which organs are most susceptible to injury in HbS?

Why?

Back 27

Altered structure of HbS results in aggregation of Hgb molecules under ANOXIC conditions

Thus sickling promoted by conditions a/w low O2 levels, increased acidity or low blood volume (dehydration), HIGH 2,3-DPG

Organs where blood moves slowly most affected (spleen, liver, kidney)

In addition, organs with high metabolic demand (brain, muscles, placenta) promote sickling by extracting more O2 from the blood.

Front 28

Describe the steps of the polyol pathway.

Where is it most active?
What is its role in lens damage?

Back 28

Most active in seminal vesicles bc sperm use fructose as primary energy source

Sorbitol can't exit cell, must be converted to fructose to leave.

In normal levels of glucose, retina is able to clear cells of sorbitol via sorbitol DH. But during hyperglycemia, sorbital DH is overwhelmed.

Leads to accumuln of sorbitol-->inc'd osmotic pressure-->influx of water

Water retention causes lens to opacify and form cataracts.

Front 29

snRNPs are synthesized by __________.

Back 29

RNA Polymerase II

Front 30

Diagnosis
Effects

Back 30

Meningioma (located adj to cerebral surface)

Will cause contralateral spastic paresis of the leg due to compression of leg-foot motor area

Front 31

Severe hypertriglyceridemia can cause ___________.

Back 31

Pancreatitis

Front 32

What is considered low HDL?

Back 32

<40 males
<50 females

Front 33

Draw the treatment algorithm for LDL/HDL/TG abnormalities.

Back 33

Front 34

Where does sympathetic arteriolar contraction occur during exercise?

Back 34

In all tissues EXCEPT actively working muscles, effectively shunting blood to exercising muscle.

Exercising muscle receives local vasodilatory factors (adenosine, K+, ATP, CO2, lactate)

Front 35

Bacillus anthracis:
Most common form of exposure

Back 35

Animals, animal products

Or through use as biological weapon

Front 36

What effects do statins have on the liver?

Back 36

Inhibit HMG CoA reductase (rate-limiting enzyme of hepatic cholesterol synthesis)

In response to dec'd serum cholesterol and LDL, liver responds by increasing LDL receptor density as a means of increasing uptake of circulating LDL.

Front 37

ApoB100:
Where is it found?
Changes with statin?

Back 37

Present in VLDL and LDL, decreases in LDL and VLDL (bc of statins) will decrease serum LDL

Front 38

Signs of Vitamin K deficiency

Back 38

Petechiae
Easy bruising

Front 39

Hyperkeratosis:
Associated deficiency

Back 39

Vitamin A deficiency

Front 40

Bilateral renal masses composed of fat, smooth muscle, blood vessels

Diagnosis
Other symptoms

Back 40

Tuberous Sclerosis

Will also see:
-Brain hamartomas
-Ash Leaf Patches
-Seizures, MR

Front 41

Back 41

Ashleaf spot-->Tuberous sclerosis

Front 42

Café au lait spots

Diagnosis
Other Symptoms

Back 42

NF I

Neurofibromas (plexiform, solitary)
Optic gliomas
Lisch nodules of iris

Front 43

Bilateral acoustic neuromas

Diagnosis
Other symptoms

Back 43

NF II
Multiple meningiomas, gliomas, ependymomas of SC

Front 44

Facial port-wine stain

Diagnosis
Other symptoms

Back 44

Sturge-Webeer

Tram Track radiopacities on Skull
MR/Seizures

Front 45

Hemorrhagic telangiectasia

Diagnosis
Other Symptoms

Back 45

Osler-Rendu-Weber

Multiple telangectasias of skin/mucosa
Recurrent epistaxis, GI bleeding (melena)

Front 46

Child develops acute onset dysuria and hematuria

Diagnosis
Viral cause

Back 46

Acute hemorrhagic cystitis
Adenovirus

Front 47

Which anti-virals require a viral kinase to become active?
Then what happens?

Back 47

Acyclovir
Valacyclovir
Famciclovir
Ganciclovir

All require viral kinase FOLLOWED BY HOST CELL KINASE to become nucleotide analogs and inhibit DNA polymerase (result in chain termination)

Front 48

Which anti-virals only require host cell kinases to become active?
Then what happens?

Back 48

Zidovudine
Cytarabine
Vidarabine

All require host cell kinase to become nucleotide analog and inhibit DNA polymerase (result in chain termination)

Front 49

34 year-old male with advanced HIV
Infected with VZV
Viral strains lack phosphorylating enzymes

Treatment

Back 49

Can’t use cyclovir because require kinases to become nucleotides.

Use:
Foscarnet (pyrophosphate analog viral DNA polymerase inhibitor)

OR

Cidofovir: antiviral nucleotide (it’s already a nucleotide, doesn’t depend on virally encoded kinase!)

Front 50

Equation for oral bioavailability of a drug.

Back 50

[(Area under curve for oral administration)x IV dose]/[(AUC IV x oral dose)]

Bioavailability for a non-IV route is always less than 1.

Area under curve must be obtained from graph of plasma concentration vs time.

Front 51

What is the effect of ACE inhibitors on GFR? How?

When are ACE inhibitors contraindicated?

Back 51

ACE inhibitors decrease Ag-II thereby causing efferent arteriole dilatation.

This reduces glomerual pressure, renal perfusion, and thus decreases GFR.

For patients who depend on efferent arteriole constriction to maintain renal perfusion, i.e., those with renal artery stenosis, ACE inhibitors can cause acute renal failure.

Front 52

Vein blanches during NE infusion
Surrounding tissue becomes pale

What's happening?
Treatment?

Back 52

NE extravasation (it's leaking outside of the vein and into nearby tissue). NE causes intense alpha-1 mediated vasoconstriction which can lead to local tissue necrosis.

Tissue necrosis best prevented with an alpha 1 blocking drug such as phentolamine.

Front 53

Phentolamine:
MOA

Back 53

alpha 1 antagonist

Front 54

ALmost all cases of endemia BUrkitt lymphoma are associated with this virus.

Back 54

EBV--implicated in immortalization of lymphoma cells.

Front 55

Stab wound to immediately above the clavicle and lateral to the manubrium:

Danger of puncturing what?

Back 55

Lung pleura

Front 56

Why is ESR elevated in inflammation?

What factors mediate this?

Back 56

During inflammation, acute phase cytokines are released: IL-1, IL-6, TNF-alpha

These stimulate hepatic production of fibrinogen (ferritin, C reactive protein, amyloid, complement, etc)

Fibrinogen causes RBCs to form stacks (rouleaux) that sediment at a faster rate than do individual RBCs.

Aggregation rate is termed ESR and is a non-specific marker of inflammn.

IL-1, 6, TNF-alpha mediate this

Front 57

What are signs of lower motor neuron lesions?

Back 57

Muscle atrophy
Fasciculations
Loss of tendon reflexes

Front 58

Cogwheel rigidity

Back 58

Parkinson's

Front 59

What does hemoglobin release and bind in:
lungs
tissue

Back 59

IN lungs, Hgb binds O2 and releases H+

IN tissues, Hgb releases O2 and binds H+

Front 60

17 year-old male
Cola-colored urine
Recent flu-like illness

Diagnosis
Pathophys

Back 60

IgA nephropathy (Berger Dz_

Dx made by detection of IgA deposits in mesangium of glomeruli

Front 61

Abdominal pain
Purpuric lesions containing IgA

Back 61

Henoch-Shonlein purpura

Front 62

When is IgA nephropathy considered a part of Henoch-Schonlein?

Back 62

When there's painless hematureia 2-3 days following URI and has purpuric skin lesions

Front 63

Signs of Vitamin E deficiency

Back 63

Neuromuscular dz:
Skeletal myopathy
Spinocerebellar ataxia
Pigmented retinopathy
Hemolytic anemia

Front 64

Signs of Vitamin A deficiency

Back 64

Night blindness
Dry Eyes
Corneal softening

Front 65

Hepatitis B vs Hepatitis C:
Which poses a greater risk of hepatocellular carcinoma?

Why?

Back 65

HBV!

In integrative phase of HBV, HBV DNA is incorporated into host genome of hepatocytes that survived immune response.

Because of this integration, risk of HCC remains elevated even when viral replication stops.

HCV increases risk by inc'd mitotic activity of infected hepatocytes (leads to genetic instability).

Front 66

What is dystonia?
Cause?

Back 66

Prolonged, repetitive muscle contractions

May be due to impaired basal gnaglia fn

Ex: writer's cramp

Front 67

Why do actinic keratoses form?

Back 67

Form due to UV damage.

Front 68

What is presbyopia?

Back 68

Diminished ability of lens to focus on close objects; due to age.

Much like wrinkles.

Front 69

99mmTc-pertechnetate scan:
Function

Back 69

Detects presents of GASTRIC mucosa

Front 70

Accumulation of pertechnetate in RLQ

Back 70

Meckel diverticulum that containst ectopic GASTRIC mucosa

Front 71

Meckel Diverticulum:
Pathophys
Presentation

Back 71

Due to failure of obliteration of omphalomesenteric duct

Lower GI bleeding due to acid secretion by ectopic gastric mucosa present in diverticulum

Can also cause RLQ pain much like appendicitis

Intestine is presidsposed to intussusception (currant jelly stools)

Front 72

What is a cross-sectional study?

Back 72

AKA prevalence study; simultaneously measures exposure and outcome.

Front 73

Diagnosis
Associated mutations

Back 73

Auer rods-->Acute myelogenous leukemia

Associated with:
M2 (AML w/maturation): t(8;21)

M3 (as in this photo; acute PROMYELOCYTIC--blasts--leukemia): t(15;17)

Front 74

Tibial nerve:
Actions
Sensory innervation
Sign of injury

Back 74

Plantar flexion
Toe flexion
Foot inversion

Senses plantar foot

Foot dorsiflexed, everted

Front 75

Femoral:
Sensory innervation

Back 75

Anterior thigh

Front 76

Saphenous:
Sensory innervation

Back 76

Medial thigh

Front 77

Superficial vs Deep Peroneal:
Sensory innervation

Back 77

Superficial: Dorsum of foot except skin between great toe and second toe (this is innervated by deep peroneal nerve)

Front 78

Panacinar emphysema:
Cause

Back 78

alpha1-antitrypsin deficiency

Front 79

Neutrophils faoil to turn blue upon nitroblue tetrazolium exposure

Back 79

CGD (NADPH deficiency), not MPO deficiency--if had MPO deficiency, NADPH would still be intact and nphils would turn blue (MPO is a separate enzyme that kills phag'd organisms)

Front 80

Which hormones have a cytoplasmic receptor?

Back 80

Cortisol
Aldosterone
Androgens
Estrogen

But migrate to nucleus once activated!

Front 81

Which hormones have a nuclear receptor?

Back 81

Thyroid hormones (no cytoplasmic receptors!)

Front 82

Nosocomial coag-negative staph infection:
Treatment

Back 82

Vancomycin ± rifampin/gentamicin

S. epidermidis exhibits widespread resistance; especially nosocomial infections

Front 83

List possible areas of MI and their associated leads/vessels.

Back 83

RCA:
-Posterior wall: V4
-Inferior wall: II, III, AVF

LAD:
Anteroseptal
V1-V5

LCX:
Lateral Wall
AVL, V5, V6