Uworld: 5-8

Front 1

Digitalis:
MOA
Side Effects
Signs of Toxicity
Toxicity Treatment

Back 1

Increases vagal tone to stimulate AV node. ( RICK OF AV BLOCK)

AE:
Fatigue, blurry vision, changes in color perception, nausea, vomiting, diarrhea

Bradycardia from inc'd AV nodal block, junctional escape beats-->v tach/fib

Tox:
Hyperkalemia due to action on Na/K ATPase

Tox tx:
Activated charcoal if suicide attempt (digitalis OD)
Insulin, kayexalate, hemodialysis to manage serum K+
Digoxin-specific Ab's

Front 2

Uretrhritis
Conjunctivitis
Arthritis

Diagnosis
Pathophys
Additional Symptom

Back 2

Reiter syndrome (reactive arthritis, ReA)

ReA = autoimmune reaction initiated by infecting pathogen (Chlamydia--urethritis, or Salmonella, Shigella, Campylobacter, Yersinia--enteritis)

20% develop sacroiliitis

Front 3

Arthritis
HLA-B27

Back 3

Reiter Syndrome

Front 4

How would initiating niacin affect diabetic medication regimen?

Back 4

Niacin can cause insulin resistance and often necessitates increase in DM medications.

Front 5

Label

Back 5

A) Breast Cancer (mortality has decreased over the years)
B) Colon Cancer (mortality relatively stable after some decrease)
C) Stomach Cancer (once very common, now very uncommon)
D) Lung Cancer (once uncommon, now leading cause of cancer mortality in women)
E) Ovarian cancer

Front 6

Define splitting.

Back 6

Unconscious belief that people are either wholly good or wholly bad.

Same person can be either good or bad at different times, as can groups of people.

Hallmark of borderline PD.

Front 7

This cell mediates delayed type hypersensitivity.

Back 7

Th1

Front 8

This cell mediates immunoglobulin class switching.

Back 8

Th2

Front 9

This cell initiates antibody response.

Back 9

Th2

Front 10

Under what conditions would a Naive CD4+ T-Cell (Th0) become a Th1 cell? Th2?

Back 10

If macrophage presents antigen to Th0, macrophage will release IL-12 which will stimulate differentiation into Th1.

THIS CAN ALSO BE ACCOMPLISHED BY IFN-GAMMA

If other APC presents antigen, IL-4 will be released by APC-->differentiation into Th2 subset.

Front 11

CD Markers for Th0 cells.

Back 11

CD3
CD4
(in addition to T cell receptor)

Front 12

What cell-cell interactions are required for activation of Th0 cells?

Back 12

MHC-II interaction with TCR and CD4 proteins

CD3 transmits signal to cell's interior

Front 13

How would a deficiency in IL-12 receptors affect T cells?

Back 13

Would make T-cells unable to differentiate into Th1 subpopulation. Then can't make IFN-gamma to activate macs.
Wouldn't be able to mount attack against delayed hypersens rxns against intracell organisms such as mycobacteria. Thus will suffer from severe mycobacterial infections and need IFN-gamma.

Front 14

Neonate
Sacral, lumbar spine agenesis
Flaccid Paralysis
Urinary incontinence

Diagnosis
Pathophys

Back 14

Caudal regression syndrome

Due to poorly controlled maternal DM

Front 15

Where is the chemoreceptor trigger zone (emesis) located?

Back 15

Dorsal Medulla (near fourth ventricle)

Front 16

Label

Include third and fourth ventricles.

Back 16

A) Thalamus (coordinates sensory, motor systems)
B ) Dorsal midbrain (superior, inferior colliculi; third ventricle just dorsal to here)
C) Ventral pons
D) Medulla (just caudal to 4th ventricle)
E) Cerebellum

Front 17

Direct vs Indirect Inguinal Hernias:
Which are more common?
Location
Site of protrusion

Back 17

Indirect more common

Direct:
Located medially to inferior epigastric vessels

Protrude through anterior abdominal wall via Hesselbach triangle; NEVER protrude into scrotum

Indirect:
Located laterally to inferior epigastric vessels.

Protrude through deep inguinal ring, can continue into scrotum and felt in inguinal canal (in scrotum).

Front 18

Varicoceles:
Where do they mostly occur?
Why?

Back 18

On left

Left gonadal (testicular or ovarian) drains into left renal vein, commonly leading to left-sided varicoceles in males with obstructions of left renal vein.

The right gonadal vein drains directly into inferior vena cava.

Front 19

6-month old
Hypoglycemia
Hypertriglyercidemia
Ketoacidosis
Hepatomegaly

Diagnosis
Pathophys

Back 19

Cori Disease--debranching enzyme deficiency.

Alpha-1,6-glucosidic branch points can't be degraded so small chain dextrin-like material accumulates in cytosol of hepatocytes.

Front 20

What EKG changes would you expect to see with WPW?

Back 20

Shortened PR interval
Delta wave at start of QRS
Widened QRS

Front 21

Describe physiologic compensatory mechanisms which exacerbate CHF.

Back 21

Dec'd Cardiac Output
-->Dec'd renal perfusion
-->Dec'd stretch of glomerular afferent arterioles
-->Renin
-->Ag I-->Ag II via ACE

Ag II:
Sodium retention, aldosterone release, VASOCONSTRICTION

(increasing preload and afterload)

Baroreceptors detect dec'd perfusion-->Inc'd sympathetic tone (inc'd HR and contractility, inc'd arterial resistance; thus, increasing afterload)

Front 22

Treatment for acute leukemia
Oliguria
Elevated Creatinine
Uric Acid Cystals

Diagnosis
Pathophys
Treatment

Back 22

Tumor lysis syndrome--lyris of tumor cells cause intracellular ions (K+, P, Uric Acid) to be released in serum.

Uric acid soluble at physiologic pH, but precipitates in normally ACIDIC environment of DISTAL TUBULES AND COLLECTING DUCT.

Tx: Urine alkalinization and hydration

Front 23

What determines what particles penetrate the nephron:
-with regard to size?
-with regard to charge?

Back 23

Size: GBM and slit diaphragms

Charge: Negatively charged anions (heparan sulfate, proteoglycans0 on endothelial cells and GM--repel negatively charged molecules such as albumin

Front 24

Why doesn't albumin pass through the nephron?

Back 24

Albumin is small enough to fit through pores in GBM; barrier to its excretion is mostly by charge selectivity.

Front 25

Minimal Change Disease:
Highly or poorly selective?
Why?

Back 25

Highly selective--mostly low-molecular weight proteins, such as albumin and transferrin, are excreted.

Front 26

Bounding femoral pulses
Head-bobbing

Back 26

Aortic regurgitation

Front 27

Describe the steps of heme synthesis.

Which would be affected by lead poisoning? What would be elevated?

Back 27

Front 28

Oval cells resembling lymphocytes
Chromogranin positive
Secretory granules in cytoplasm

Diagnosis
Origin

Back 28

Small cell carcinoma--CORRELATED WITH SMOKING

Arises from primitive cells of basal layer of bronchial epithelium

Front 29

Xanthomas
Lack ApoE3, ApoE4

Diagnosis
Pathophys

Back 29

Familial dysbetalipoproteinemia

Without ApoE3/4, liver can't efficiently remove chylomicrons and VLDL remnants from circulation, causing accumulation in serum and elevations in cholesterol and TG levels.

Front 30

List the most important apolipoproteins and their functions.

Back 30

ApoA-I: LCAT activation (cholesterol esterification)

ApoB-48: Chylomicron assembly, secretion by intestine

ApoB-100: LDL particle uptake by extrahepatic cells

ApoC-II: Lipoprotein lipase activaiton

ApoE-3/4: VLDL and chylomicron remnant uptake by liver cells

Front 31

5 year-old female
Erythema, Scaling, Hyperpigmentation on sun-exposed areas
Rapidly enlarging nevi on hands

Diagnosis
Pathophys

Back 31

Xeroderma pigmentosum--dec'd ability to repair DNA following damage by UV light (requires excision)

Front 32

Tetanus:
Species name
Describe disease progression

Back 32

Clostridium tetani (spores! anaerobe!)

Toxin released at wound-->travels retrograde on motor neurons into spinal cord-->inhibits inhibitory interneurons and upregulates firing of primary motor neurons

Front 33

Headache
Photosensitivity
Nausea, vomiting
Gram-negative kidney bean-shaped cocci

Diagnosis
Pathophys

Back 33

Infection with N. meningitidis

Lipooligosaccharide of outer membrane is responsible for toxic effects (also associated with mortality)

LOS causes sepsis by induction of systemic inflammatory response via TNF-alpha, IL-1, IL-6, IL-8 due to LOS interaction with TLR4.

Beware of Waterhouse-Friderichsen (adrenal cortical hemorrhage)

Front 34

Ring-enhancing lesions in both cerebral hemispheres
AIDS patient

Diagnosis
Pathophys
Treatment

Back 34

Toxoplasmosis

Toxoplasma gondii = obligate intracellular protozoan; cat = definitive host

Can develop encephalitis with multiple necrotizing brain lesions

Tx: Pyrimethamine, sulfadiazine

Front 35

What are the two most common causes of focal brain lesions in HIV-positive patients?

Etiology of both?

Back 35

1) Toxoplasmosis due to cat poop contaminated food/water

2) Primary CNS lymphoma composed of B-lymphocytes, likely secondary to EBV

Front 36

Back 36

Tzanck preparation
Presence of multinucleated giant cells with some intranuclear inclusions

Suggestive of HSV or VZV

Front 37

5 year-old male
Fever
Vesiculoulcerative gingivostomatitis
Cervical LAD

Diagnosis

Back 37

Primary infection with HSV-1

Front 38

How does primary infection with HSV-1 differ in presentation from reactivation of a latent HSV infection?

Back 38

Primary: Fever, vesiculoulcerative gingivostomatitis, cervical LAD

Latent: If in trigeminal ganglia-->perioral blisters or "cold sores"

Front 39

Back 39

Dermatomyositis

Front 40

What is a heliotrope rash?

Back 40

Rash on upper eyelids (think dermatomyositis)

Front 41

Dermatomyositis:
Presentation
Antibodies

Back 41

Gottron papules (flat-topped violaceous papules present over joints of fingers)
Heliotrope rash (on upper eyelids)


Anti-nuclear (nonspecific)
Anti-Jo1 (specific)

Front 42

Benzodiazepines:
MOA
Side Effects
Shortest acting
Medium acting
Longest acting

Which are most addictive?

Back 42

Bind GABA-a receptors and enhance inhibitory effect of GABA

Can be used to treat insomnia (= hypnotics), panic/anxiety disorders (=anxiolytics), anticonvulsants (seizures assocd w/EtOH withdrawal)

AE: Daytime drowsiness, ataxia (RISK OF FALLING)

Shortest acting: Alprazolam (highest risk of addiction)
Medium: Lorazepam
Longest acting: Flurazepam (SEVERE daytime drowsiness; lower risk of addiction)

Front 43

These drugs block iodide absorption by the thyroid via competitive inhibition.

Back 43

Perchlorate
Pertechnetate

Front 44

These drugs decease the formation of thyroid hormones by inhibiting thyroid peroxidase.

Back 44

Methimazole
Propylthiouracil (PTU)

Front 45

This drug inhibits the synthesis and release of thyroid hormones.

Back 45

Iodide

Front 46

What is the action of thyroid peroxidase?

Back 46

I- -->I0 (necessary to form thyroid hormone)

Front 47

What cells exhibit tight junctions?

Back 47

Apices of glandular cells

Front 48

What cells exhibit hemidesmosomes?

Back 48

Basal surface of keratinocytes in stratified squamous epithelium

Attaches it to basal lamina

Front 49

What cells exhibit desmosomes?

Back 49

Stratified squamous epithelium--contributes to structural cohesiveness of tissues subject to mechanical stress

Front 50

Equilibration of O2 in a normal patient at rest is _______-limited.

Why?
When is this not true?

Back 50

Perfusion-limited, bc equilibration occurs before leaving capillary

Not true in emphysema, pulmonary fibrosis, exercise--then becomes diffusion-limited

Front 51

Lyme disease:
Early vs Late Stages (presentation)
Treatment

Back 51

Early: flu-like syx, erythema migrans
(a second stage may involve AV block and Bell's palsy0

Chronic: Asymmetric large joint arthritis, encephalopathy

Tx:
Doxycyline
OR
PCN-type abx (ex: ceftriaxone)

Note: Borrelia burgdorferi ~ syphilis bc it's a spirochetal infection

Front 52

MTX AEs

Back 52

Remember: MTX works by inhibiting DHF reductase

Stomatitis (painful mouth ulcers)
Hepatotoxicity (hepatitis, fibrosis, cirrhosis)
Myelosuppression
CONTRAINDICATED IN PREGNANCY

Front 53

Cola-colored urine
Facial edema
Recent outbreak of skin infection

Diagnosis

Back 53

Post-strep GN

Front 54

What is the most important prognostic factor in poststreptococcal glomerulonephritis?

Back 54

Age

95% of affected children, but ONLY 60% OF AFFECTED ADULTS, recover completely.

Front 55

Needle-shaped, negatively birefrignent crystals

Back 55

Gout crystals

Front 56

Acute pain, swelling of first metatarsophalangeal joint
Needle spirate shows needle-shaped, negatively birefringent crystals

Diagnosis
Treatment
Treatment MOA, AEs

Back 56

Acute gouty arthritis

Tx: Colchicine
MOA: Binds intracellular tubulin and prevents its polymerization into microtubules (INHIBITS MT FORMATION) in leukocytes-->reduces nphil chemotaxis in sites with uric acid crystal deposition

AE: nausea, vomiting (GI mucosa affected by inhibition of tubulin polymerization)

Front 57

Mediastinal widening
Diastolic murmur over left sternal border
Serum FTA-ABS positive

Diagnosis
Pathophys

Back 57

Aortic regurgitation + mediastinal widening = AORTIC ANEURYSM

FTA-ABS positive = syphilis

Thus, must be tertiary syphilis:
-Vasa vasorum endarteritis and obliteration-->inflammation and weakening of adventitia
-->can extend to dilate aortic valve

Front 58

Pleural thickening with calcifications on lower lung fields and diaphragm

Back 58

Asbestosis

localization to mid-lung zones and diaphragm = hallmark

Front 59

Nodular densities and eggshell calcifications on hilar nodes

Back 59

Silicosis

Front 60

Waxing and waning lymphadenopathy

Back 60

Follicular lymphoma (it's of B cell origin BTW)

Front 61

Under what specific histologic conditions does a tumor become invasive?

Back 61

1) Detachment from surrounding cells via down-regulation of E-cadherins

2) Ability of detached cells to adhere to BM's through inc'd laminin and other adhesion molecules.

3) Invasion via secretion of METALLOPROTEINASES (normally involved in tissue remodeling)

Front 62

What is papilledema? What causes it?

Back 62

Optic disc swelling due to inc'd intracranial pressure

Front 63

Papilledema
Dry Skin
Hepatosplenomegaly
No intracranial mass

Back 63

Vitamin A overuse