5/31 UWorld Flashcards

1
Q

What is detection bias?

A

Refers to the fact that a risk factor itself may lead to extensive diagnostic investigation and increase the probability that a disease is identified

E.g. smokers may undergo increased imaging surveillance due to smoking status, which would detect more cases of cancer in general

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the 4 glycogen storage diseases?

A

THINK: Very Poor Carbohydrate metabolism

Type I = Von Gierke

Type II = Pompe

Type III = Cori

Type V = McArdle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the deficient enzyme and presentation of Von Gierke disease?

A

· Deficient glucose-6-phosphatase

· Causes a defect in both glycogenolysis and gluconeogenesis

· Severe fasting hypoglycemia, lactic acidosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the deficient enzyme and presentation of Pompe diseaes?

A
  • Deficient in lysosomal alpha-1,4-glucosidase
    • Enzyme usually degrades small amounts of glycogen trapped in lysosomes
    • Enzyme deficiency leads to glycogen accumulation within lysosomes (appears as periodic acid-schiff-positive material
  • Cardiomegaly, hypertrophic cardiomyopathy, exercise intolerance, hypotonia
    • THINK: Pompe = fat = symptoms of obesity
  • Shortened life expectancy
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the deficient enzyme in Cori disease

A
  • Deficient in debranching enzymes
    • THINK: Cori wants me to climb his “straight branch”
  • Causes a defect in glycogenolysis but gluconeogenesis is fine
    • Milder version of Von Gierke disease
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the deficient enzyme and presentation of McArdle diseas

A
  • Deficient in skeletal muscle glycogen phosphorylase
    • McArdle = Muscle
  • Can make glycogen but can’t break it down
  • Increased glycogen in muscle = increased osmotic pressure = swelling and lysis of myocytes = rhabdomyolysis = myoglobin in serum = myoglobin in urine (myoglobulinuria)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Stimulation of what nerve can improve the symptoms of obstructive sleep apnea

A
  • Stimulation of the hypoglossal nerve using an implantable nerve stimulator causes the tongue to move forward slightly, increased the anteroposterior diameter of the airways
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the sequence of events that occurs after binding/activation of a Gq receptor

A

Binding/activation of Gq = activation of phospholipase C (which stimulates hydrolysis of membrane-bound phospholipids) = PLC releases IP3 and DAG = IP3 liberates intracellular Ca2+ and DAG activates protein kinase C = ultimately leads to smooth muscle contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the sequence of events that occurs after binding/activation of a Gs receptor

A

Binding/activation of Gs = activation of adenylate cyclase = adenylate cyclase cleaves ATP to form cAMP = cAMP activates protein kinase A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the difference between Bipolar I, Bipolar II, and Cyclothymic disorder

A
  • Bipolar I
    • 1 manic episode +/- a hypomanic or depressive episode
  • Bipolar II
    • Hypomanic episode + major depressive episode
  • Cyclothymic Disorder (milder)
    • Mild hypomanic symptoms + mild depressive symptoms
    • Lasts > 2 years
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What STI is associated with large and painful inguinal lymph nodes (“buboes”)

A

Chlamydia trachomatis serotypes L1-L3

Lymphogranuloma venereum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What type of drug is Phenelzine

A

MAO inhibitor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What type of drug is Sertaline

A

SSRI

Sertraline = Desert airline

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What type of drug is Duloxetine

A

SNRI

Duloxetine = dual copier/scanner

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What type of drug is citalopram?

A

SSRI

Citalopram = City

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the 3 most common causes of aortic stenosis?

A

Congenitally abnormal valve with calcifications (e.g. bicuspid valve)

Calcified normal valve

Rheumatic heart disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the feared complications associated with antiphospholipid antibodies

A

They cause paradoxical PTT prolongation, but produce a hypercoagulable state

Also associated with unexplained, recurrent pregnancy loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the symptoms associated with lupus?

A
  • RASH OR PAIN
    • R – Rash (malar or discoid)
    • A – Arthritis
    • S – Serositis
    • H – Hematologic disorders
    • O – Oral/nasopharyngeal ulcers
    • R – Renal disease (diffuse proliferative glomerulonephritis or membranous glomerulonephritis)
    • P – Photosensitivity
    • A – Antinuclear antibodies (ANA)
    • I – Immunologic disorder (anti-dsDNA, anti-Smith, or anti-phospholipid)
    • N – Neurologic disorders (seizures)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

In what part of the brain do you see atrophy in Huntington’s

A

Caudate and putamen

20
Q

In what disease will you see dementia + personality changes and/or aphasia

A

Pick disease

21
Q

In what disease will you see dementia + visual hallucinations

A

Lewy body dementia

22
Q

Is BPH due to hypertrophy or hyperplasia

A

Hyperplasia

23
Q

What pathology occurs in the lateral/middle vs. posterior lobe of the prostate

A

BPH = lateral/middle (compression of urethra into vertical slit)

Prostatic adenocarcinoma = posterior (felt on rectal exam)

24
Q

Describe what parts of meiosis I and meiosis II the egg is arrested in, and what allows the egg to continue on in the process

A

Primary oocytes arrested tin Prophase I until ovulation

Secondary oocytes arrested in Metaphase II until fertilization (an egg met a sperm)

25
Q

What is Mittelschmerz

A

Transient mid-cycle ovulatory pain

Associated with peritoneal irritation

26
Q

What are the stimulators and products of theca and granulosa cells?

A
  • Theca cells
    • Stimulated by LH
    • Produce androstenedione from cholesterol via desmolase
  • Granulosa cells
    • Stimulated by FSH
    • Produce estrogen (estradiol) from androstenedione via aromatase
27
Q

What is vaginal adenosis?

A

Persistence of columnar epithelium within the upper vagina

Lower 1/3 of vagina derived from urogenital sinus à squamous epithelium

Upper 2/3 of vagina derived from Mullerian duct à columnar epithelium

Normally, squamous epithelium will grow upwards to replace the columnar epithelium

Associated with diethylstilbestrol (DES) in utero and clear cell adenocarcinoma

28
Q

Common metastatic location of prostatic adenocarcinoma

A

Bone

29
Q

Serious complication of invasive cervical carcinoma

A

Lateral invasion can block ureters leading to hydronephrosis and postrenal failure

30
Q

What serum hormone levels are indicative of PCOS?

A

Elevated LH:FSH ratio (LH:FSH > 2)

31
Q

What is the presentation and lab values of embryonal carcinoma of the testes?

A

Malignant tumor comprised of immature, primitive cells that may produce glands

Painful, hemorrhagic mass with necrosis

Increased hCG and normal AFP

32
Q

Complication of PCOS

A
  • Increased risk of endometrial cancer secondary to unopposed estrogen from repeated anovulatory cycles
33
Q

What is the presentation, histology, and prognosis of seminoma?

A

Most common type of testicular cancer

Malignant

Painless, homogenous testicular enlargement

“Fried egg” appearance under histology

Radiosensitive – excellent prognosis

34
Q

What is xeroderma pigmentosum?

A

Autosomal recessive defect in enzymes required for nucleotide excision repair - inability to repair pyrimidine dimers caused by UV rays

Presentation: photosensitivity, increased pigmentation, xerosis (abnormal skin dryness)

Increased risk of skin cancer

35
Q

Describe the pathophysiology of exophthalmos in Graves disease

A

Lymphocytes infiltrate the orbital tissues and secrete cytokines that stimulate fibroblasts to secrete increasing amounts of glycosaminoglycan ground substance such as hyaluronic acid. This increased hyaluronic acid draws water into the orbit resulting in extraocular muscle edema. Combined with interstitial edema, this process pushes the globe outward (proptosis). A sensation of grittiness and excessive tearing occur because the lids are now unable to completely cover the proptotic globe. Desiccation and keratitis may result

36
Q

What is the defective DNA mechanism in Hereditary nonpolyposis colorectal cancer (HNPCC)

A

Defect in DNA mismatch repair (MMR)

Aka Lynch syndrome

37
Q

Presentation of Neurofibromatosis type 1 vs type 2

A
  • Neurofibromatosis type 1
    • Caused by mutation in NF1 gene on chromosome 17
      • This gene is responsible for control of cell division
    • Neurocutaneous disorder characterized by café-au-lait spots, cutaneous neurofibromas, optic gliomas, pheochromocytomas, Lisch nodules (pigmented iris hamartomas)
    • Neurofibromas consist of proliferation of Schwann cells, fibroblasts, and neurites
  • Neurofibromatosis type 2
    • Due to mutation of NF2 gene on chromosome 22
    • Bilateral acoustic schwannomas, juvenile cataracts, meningiomas, and ependymomas
    • Presentation:
      • Hearing loss, tinnitus, balance problems, hyperpigmented skin lesions, cataracts
    • REMEMBER 2’s:
      • Chr 22
      • Bilateral hearing loss
      • NF Type 2
      • Cataracts
38
Q

What is the MOA and uses of the drug Paclitaxel

A

Hyperstabilization of polymerized microtubules in M phase so that mitotic spindle cannot break down and anaphase cannot occur

Used to treat ovarian and breast carcinoma

Also prevents intimal hyperplasia, so can be used as coating in stent placement to prevent stent restenosis

39
Q

Differentiate somatic symptoms disorder vs. Illness anxiety disorder

A

Somatic symptom disorder - excessive concern about somatic symptoms, frequent use of medical services, and impaired functioning

Illness anxiety disorder - prolonger fear or concern about getting or having a disease with minimal or no actual physical symptoms

40
Q

What are the diseases associated with VHL?

A

Hemangioblastoma

Angiomatosis

Bilateral renal cell carcinoma

Pheochromocytoma

41
Q

Describe the defect in medium-chain acyl CoA dehydrogenase deficiency (MCAD)

A
  • Deficient enzyme for beta-oxidation à decreased ability to breakdown fatty acids into acetyl-CoA à accumulation of fatty acyl carnitines in blood with hypoketotic hypoglycemia
  • Presentation:
    • Vomiting, lethargy, seizures, coma, liver dysfunction
    • Can lead to sudden death in infants or children
  • Treatment:
    • Avoid fasting
42
Q

What are the adult derivatives of the prosencephalon, mesencephalon, and rhombencephalon?

A
  • Prosencephalon à forebrain
    • Telencephalon
      • Walls à cerebral hemisphere
      • Cavities à lateral ventricles
    • Diencephalon
      • Walls à thalamus, hypothalamus
      • Cavities à third ventricle
  • Mesencephalon à midbrain
    • Mesencephalon
      • Walls à midbrain
      • Cavity à aqueduct
  • Rhombencephalon à hindbrain
    • Metencephalon
      • Walls à pons, cerebellum
      • Cavity à upper 4th ventricle
    • Myelencephalon
      • Walls à medulla
      • Cavity à lower 4th ventricle
43
Q

What cardiomyopathy is associated with chronic, excessive alcohol intake?

A

dilated cardiomyopathy

44
Q

Describe control of lac operon expression

A

Lac operon controls the expression of beta-galactosidase (necessary for lactose metabolism) in order to ensure that glucose is used preferentially over lactose

CAP is the transcription factor that determines if the gene is transcribed or not

When glucose is low, CAP will be activated and there will be increased transcription

Repressor proteins are present (and block binding of RNA polymerase and initiation of transcription) unless lactose is high

When lactose is high, repressor protein will unbind from the operator site, and transcription will be increased

So ideal transcription occurs when there is low glucose (à increased CAP) and high lactose (à decreased repressor protein)

45
Q

Describe chromosomes and hormone levels in Klinefelter syndrome (testosterone, estrogen, LH, FSH)

A
  • 47, XXY
  • Atrophied/hyalinized seminiferous tubules -> decreased testosterone and inhibin B -> increased FSH and LH -> increased estrogen production
46
Q
A