5/17 Mixed Flashcards Preview

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Flashcards in 5/17 Mixed Deck (49):
1

Good pasture syndrome

Renal failure and pulmonary hemorrhage in patinets with anti-GBM antibodies
Hypertension, hematuria, moderate proteinuria = nephritic syndrome
Linear deposits of ig along the glomerular basement membrane (IgG and C3) --target collagen type IV
Rapidly progressive glomerulonephritis
Glomerular crescents on light microscopy

2

Bacterial joint infection

High synovial fluid leukocyte count (>100,000) and absent crystals on microscopic examination suggest bacterial joint infection
Septic arthritis requires antibiotic treatment to prevent joint destruction, osteomyelitis, and sepsis
Often due to gonococcus in young age group

3

Which nerve is at risk of injury during thyroidectomy

External branch of the superior laryngeal nerve
Due to proximity to superior thyroid artery and vein
Innervates the cricothyroid muscle

4

Cirrhosis

Diffuse hepatic fibrosis with replacement of the normal lobular architecture by fibrous-lined parenchymal nodules
Chronic viral hepatitis, alcohol, hemochromatosis, and nonalcoholic fatty liver disease are the most common causes of cirrhosis in the US
Can lead to portal hypertension, which can cause gastroesophageal varices (prone to rupture, massive GI hemorrhage, death)

5

Telomerase and telomeres

Telomerase is a reverse transcriptase that lengthens telomeres by adding TTAGGG repeats to the 3' end of chromosomes
Stem cells have long telomeres due to high telomerase activity, allowing them to proliferate indefinitely in a controlled manner
Ex. epidermal basal cells

6

Tuberculoid leprosy

Least severe form
Mycobacterium leprae
Limited by intact CMI response (Th1 mediated)
Milk skin plaques develop, associated with hypopigmentation, hair follicle loss, focally decreased sensation

7

MOA of myasthenia gravis

Autoantibodies against postsynaptic nicotinic Ach receptors results in blockade of active site, receptor internalization/degradation, and damage to the motor end plate due to complement fixation
Decreased numbers of functional Ach receptors at NMJ
Reduces end-plate potential (threshold potential is not reached, muscle cells do not depolarize)

8

Cannulation of the femoral vein

Should occur approximately 1 cm below the inguinal ligament and just medial to the femoral artery pulsation
NAVL

9

Cavernous hemangioma

Most common benign liver tumor
Adults 30-50
Cavernous, blood-filled vascular spaces of variable size lined by single epithelial layer
DO NOT BIOPSY: procedure can cause fatal hemorrhage and is of low diagnostic yield

10

Principle site of uric acid precipitation?

Uric acid is soluble at physiologic pH but can precipitate in normally acidic environment of the distal tubules/collecting ducts
Tumor lysis syndrome occurs when tumors with a high cell turnover are treated with chemotherapy > causes intracellular ions (K, P, uric acid) to be release into serum
Prevention includes urine alkalinization and hydration

11

Fractures of the orbital floor

Commonly result from direct frontal trauma to the orbit
Infraorbital nerve runs along the orbital floor before exiting the skull just inferior to the orbit
Damage can result in paresthesia of the upper cheek, upper lip, upper gingiva
Inferior rectus muscle can become entrapped, limiting superior gaze

12

Hypocalcemia

Signs: muscle cramps, perioral paresthesias, hypotension, laryngospasm, Chvostek sign (facial muscle contraction elicited by tapping on facial nerve anterior to the ear), Trousseau sign (carpopedal spasm triggered by prolonged inflation of a blood pressure cuff around the arm)
Most common cause = injury to parathyroid glands during thyroid surgery

13

Dobutamine

B-adrenergic agonist (B1> B2> a1)
Rx: refractory heart failure associated with severe LV systolic dysfunction and cardiogenic shock
+ inotropic effect (increased contractility), + chronotropic effect (increased heart rate), increase myocardial O2 consumption, vasodilation

14

Inflammatory breast cancer

Peau d' orange (erythematous rash, itchy, firm/coarse skin texture)
Breast edema
Cancer obstructs lympathetic drainage

15

Etanercept

Tumor necrosis factor-alpha (TNF-a) inhibitor
Added to methotrexate to treat moderate to severe RA
Fusion protein linking a soluble TNF-a receptor to the Fc component of human Ig.
Reduces the biological activity of TNF-a by acting as a decoy receptor

16

Suffix of a biological agent

Monoclonal antibody (-mab)
Receptor molecule (-cept)
Kinase inhibition (-nib)

17

Spleen

Most common intra-abdominal organ injured during blunt trauma
Of mesodermal origin (dorsal mesentery)
Supplied by the splenic artery (a branch of the major foregut vessel, the celiac trunk)

18

Case-control study

Used to compare the exposure of people with the disease (cases) to the exposure of people without the disease (controls). The main measure of association is the exposure odds ratio.

19

Adjustable gastric banding

to encircle the upper stomach, the gastric band must pass through the lesser omentum

20

Beta blockers in the treatment of hyperthyroidism

Reduces heart rate and feelings of anxiety/agitation
Decreases the peripheral conversion of T4 to T3 by inhibiting iodothyronine deiodinase

21

The common and proximal carotid arteries derive from which aortic arch?

Third

22

Food borne botulism

Diplopia, dysphagia, dysphonia
Electrodiagnostic studies reveal normal nerve conduction velocity but decreased compound muscle action potential (CMAP), repetitive nerve stimulation leads to facilitation of CMAP

23

Orchiopexy

Surgical repair of an undescended testicle lodged in the inguinal canal
Reduce testis through the superficial inguinal ring and fix it in the scrotum
The superficial and deep inguinal rings are physiologic openings in the external abdominal oblique aponeurosis and the transversalis fascia, respectively.

24

Huntington disease pathogenesis

Hypo-acetylated histones bind tightly to DNA and prevent transcription of genes in their associated regions
Alteration of gene expression in Huntington disease occurs in part due to deacetylation of histones
This prevents the transcription of certain genes that encode for neurotrophic factors, contributing to neuronal cell death

25

Toxic megacolon

Complication of ulcerative colitis
Abdominal pain/distension, blood diarrhea, fever, signs of shock
Plain abd x-ray is preferred diagnostic imaging study
Barium contrast studies and colonoscopy are contraindicated due to the risk of perforation

26

Alpha-1 antitrypsin deficiency

Serum protein, inhibits neutrophil elastase, reduces tissue damage caused by inflammation
Histologically- reddish-pink, periodic acid-Schiff positive granules of unsecreted, polymerized AAT in the periporal hepatocytes

27

Photoaging (wrinkles)

Product of excess exposure to ultraviolet A wavelengths and is characterized by epidermal atrophy with flattening of rete ridges
Decreases collagen fibril production and increased degradation of collagen and elastin in the dermis

28

Odds ratio (OR)

Measure of association between an exposure and an outcome
In an standard contingency table, OR=ad/bc

29

Sarcoidosis

Hilar adenopathy, pulmonary disease, constiutional symptoms
NON-CASEATING GRANULOMAS (distinguishes sarcoidosis from tuberculosis infection)

30

G6PD deficiency inheritance

X-linked recessive inheritance

31

Glucagonoma

Rare tumor of alpha-cells
Necrolytic migratory erythema
Hyperglycemia
Normocytic normochormic anemia
Elevated levels of glucagon in the serum

32

Arteriovenous concentration gradient (inhaled anesthetics)

Reflects the overall tissue solubility of an anesthetic. Anesthetics with high tissue solubility are characterized by large arteriovenous concentration gradients and slower onsets of action

33

Amiodarone

Class III antiarrhythmic drug
Superventricular and ventricular arrhythmias
Block potassium channels, inhibit the outward K currents, prolong repolarization and total action potential duration
APD is ~ QT interval
unlike other drugs that cause QT prolongation, amiodarone has a VERY LOW RISK of inducing TORSADES DE POINTES

34

Direct hernias

Caused by weakness of the transversalis fascia in Hesselbach's triangle
Medial to the inferior epigastric vessels, protrude through the external inguinal ring, covered by external spermatic fascia

35

IgA protease

Produced by N. meningitidis, N. gonorrhoeae, S, pneumo, H. flu
Cleaves secretory IgA at its hinge region, rendering it ineffective
Secretory IgA exists on mucosal surfaces and in secretions and acts to bind and inhibit the action of pili as well as other cell surface Ag that normally mediate mucosal adherence and subsequent penetration

36

Attack rate

Ratio of the number of people who contract an illness divided by the number of people who are at risk of contracting that illness

37

Most common causes of death in patients with tricyclic antidepressant overdose

Cardiac arrhythmias and refractory hypotension
Inhibition of fast Na channels in cardiac myocytes (and the His-Purkinje system) is thought to be the major underlying cellular event

38

Third heart sound (S3)

Occurs during early diastole and is best heard with the bell of the stethoscope over the cardiac apex while the patient is in the left lateral decubitus position at end expiration
Can be normal in healthy young adult
Considered abnormal in patients >40 and suggests ventricular enlargement (rapid passive ventricular filling)

39

Lateral ankle sprain

Due to inversion of a plantar-flexed foot and most commonly involves the anterior talofibular ligament
Stronger forces can cause joint instability by injuring additional ligaments

40

Retroperitoneal hematomas

Abdominal and pelvic trauma
Pancreatic injury is a frequent cause

41

Following IV administration, a highly lipophilic drug (anesthetics) will...

Be rapidly distributed to organs with high blood flow (brain, liver, kidneys, lungs)
The drug is then slowly redistributed to tissues with relatively low blood flow (skeletal muscle, fat, bone)
This accounts for the short duration of action of many commonly used anesthetics, such as propofol

42

Carcinoid tumors

If confined to the intestine- do not cause carcinoid syndrome (secretory products are metabolized by the liver before entering systemic circulation
Intestinal carcinoids that metastasize to the liver and extraintestinal (bronchial) carcinoids release vasoactive substances that avoid first pass metabolism resulting in carcinoid syndrome (flushing, diarrhea, bronchospasm)

43

E. coli

Lactose fermenting, INDOLE POSITIVE gram-negative rods that are important cause of UTI in women

44

Precursor proteins or peptides responsible for localized amyloidosis (confined to a single, specific organ)

Cardiac atria: atrial natriuretic peptide
Thyroid gland: calcitonin
Pancreatic islets: islet amyloid protein (amylin)
Cerebrum/cerebral blood vessels: B-amyloid protein
Pituitary gland: prolactin

Immune globulin light chains cause multi-organ amyloid deposition in primary systemic amyloidosis

45

Annular pancreas

Pancreatic tissue encircling the descending duodenum
Caused by failure of the ventral pancreatic bud to properly migrate and fuse with the dorsal bud during the seventh and eighth week of fetal development
Usually asymptomatic but may present with duodenal obstruction or pancreatitis

46

Risks of secondhand smoke exposure

Prematurity, low birth weight
Sudden infant death syndrome
Middle ear disease (otitis media)
Asthma
Respiratory tract infections

47

Duchenne Muscular dystrophy

Can occur due to nonsense mutations in the dystrophin gene
Nonsense mutations introduce premature stop codons (UAA, UAG, UGA)

48

Ion channels

When a specific ion channel opens, the respective ions will flow across the membrane in a direction that brings the resting membrane potential closer to that ion's equilibtrium potential

49

Vesicoureteral reflux

Retrograde urine flow from bladder into the ureter
Hydrostatic pressure of refluxing urine along with infections due to ascending bacteria cause inflammation
Compound papillae in upper and lower poles of kidney are most susceptible to reflux induced damage which appears as dilated calyces with overlying renal cortical scarring
can lead to hypertension