6/4 Mixed

Question 1

Mullerian aplasia

Answer 1

Aka vaginal agenesis or Mayer-Rokitansky-Kuster Hauser (MRKH) syndrome
Variable uterine development with no upper vagina , primary amenorrhea, normal ovaries (secrete estrogen normally and enable regular development of secondary sexual characteristics

Question 2

Topical capsaicin

Answer 2

Causes defunctionalization of afferent pain fibers and depletion of substance P
Initial application results in a burning and stinging sensation, but chronic exposure leads to reduced pain transmission

Question 3

Androgenetic alopecia

Answer 3

The most common cause of hair loss in both males and females
The pattern and severity of the baldness depends on both hormonal (circulating androgens) and genetic factors and vary between males and females.
The condition is polygenic with variable expressivity.

Question 4

Aortic stenosis murmur

Answer 4

Systolic ejection-type, crescendo-decrescendo murmur that starts after the first heart and typically ends before the A2 component of the second heart sound
The intensity of the murmur is proportional to the magnitude of the left ventricle to aorta pressure gradient during systole.

Question 5

Rx: hyperaldosteronism (aldosterone secreting tumor, Conn’s Syndrome)

Answer 5

Aldosterone excess will cause hypertension, hypokalemia, metabolic alkalosis and depressed renin
Aldosterone antagonists such as spironolactone or eplerenone can be used as medical therapy for Conn’s syndrome

Question 6

5-alpha reductase inhibitors

Answer 6

Finasteride, dutasteride
Block the conversion of testosterone to DHT in the prostate
These drugs reduce prostate volume in patients with benign prostatic hyperplasia and relieve the fixed component of bladder outlet obstruction

Question 7

ACTH

Answer 7

Major trophic hormone of the zone FASCICULATA and RETICULARIS, whereas the zona glomerulosa is primarily regulated by agiotensin II
Prolonged ACTH stimulation causes HYPERPLASIA of the zona fasciculata and reticularis, resulting in excessive cortisol production

Question 8

Primary hemochromatosis

Answer 8

HFE protein mutations are the most common cause
Decressed expression found to reduce endocytosis of the iron-transferrin complex
Inactivation of the HFE protein results in decreased hepcidin synthesis by hepatocytes and increased DMT1 expression by enterocytes, leading to iron overload
Patients with hemochromatosis are at an increased risk for liver cirrhosis and hepatocellular carcinoma

Question 9

Pathogenesis of alcohol-induced hepatic steatosis

Answer 9

Decrease in free fatty acid oxidation secondary to excess NADH production by the 2 major alcohol metabolism enzymes, alcohol dehydrogenase and aldehyde dehydrogenase

Question 10

Key growth factors that promote angiogenesis in neoplastic and granulation tissue

Answer 10

Vascular endothelial growth factor (VEGF)

Fibroblast growth factor

Question 11

Ataxia telangiectasia

Answer 11

Cerebellar ataxia, telangiectasias, increased risk of sinopulmonary infections
AR inheritance, defect in the gene that codes for the ATM gene which plays a role in DNA break repair
The immune deficiency primarily manifests as an IgA deficiency and predisposes to infections of the upper and lower airways

Question 12

Nucleolus

Answer 12

Site of ribosomal subunit maturation and assembly
RNA polymerase I synthesizes the vast majority of rRNA from within the nucleolus
Large nuclei contain prominent, round, basophilic bodies= nucleolus

Question 13

Chronic Myelogenous Leukemia (CML)

Answer 13

Can have a similar presentation to leukemoid reaction
Leukocyte (neutrophil) alkaline phosphatase level is normal or elevated in a leukemoid reaction, decreased in CML
Dx of CML: Philadelphia chromosome t(9;22) or BCR-ABL fusion gene or mRNA

Question 14

Thayer-Martin selective medium

Answer 14

Used to isolate Neisseria species from clinical cultures
Chocolate (heated blood) agar that contains vancomycin to inhibit growth of gram-positive organisms, colistin (polymyxin) to inhibit gram-negative bacteria, nystatin to inhibit the growth of fungi, and trimethoprim to inhibit the growth of gram-negative organisms other than Neisseria, such as the Proteus species

Question 15

Vitamin A deficiency

Answer 15

Causes night blindness and hyperkeratosis
Deficiency of this fat-soluble vitamin can develop in patients with biliary disorders, exocrine pancreatic insufficiency, or intestinal malabsorption

Middle aged woman with generalized pruritis and vitamin A deficiency > likely has primary biliary cirrhosis (PBC), autoimmune disease, destruction of small bile ducts in liver (pruritus due to mild hyperbilirubinemia)

Question 16

Hypothyroidism causes mypathy

Answer 16

Common cause of elevated creatine kinase (CK) due to hypothyroid myopathy
Can be the first manifestation of hypothyroidism
Fatigability, weight gain, myoedema (focal mounding of muscle following percussion), myalgia, proximal muscle weakness, cramping
Measure TSH in all patients with unexplained CK elevation

Question 17

Biochemical abnormality in Alzheimers

Answer 17

Decreased acetylcholine levels in the hippocampus and nucleus basalis of Meynert (participates in memory and cognition. Diminished activity of choline acetyltransferase in these cerebral structures is the cause.

Question 18

Ventromedial nucleus (VMN) of hypothalamus

Answer 18

Thought to be the center of satiety

Lesions of the VMN can results in hyperphagia and obesity

Question 19

Cryptococcus neoformans

Answer 19

India ink staining of the CSF shows round or oval BUDDING YEAST

Question 20

CREST syndrome/ systemic sclerosis

Answer 20

Pulmonary HTN develops in patients with systemic sclerosis as a result of damage to the pulmonary arterioles (intimal thickening of pulmonary arteries)
It manifests with an accentuated pulmonary component of the second heart sound and signs of right-sided heart failure due to cor pulmonale

Question 21

High-frequency deep brain stimulation in Parkinson Disease

Answer 21

Nigrostriatal degeneration in PD reduces activity of the thalamus and its projections to the cortex, resulting in bradykinesia and rigidity
Patients with medically intractable symptoms of PD may benefit from high-frequency deep brain stimulation of the GLOBUS PALLIDUS INTERNUS or SUBTHALAMIC NUCLEUS as it promotes thalamo-cortical disinhibition with improved mobility

Question 22

Mifepristone

Answer 22

Progesterone antagonist

Used with misoprostol (prostaglandin E1 agonist) to terminate a first trimester pregnancy

Question 23

Number needed to harm = 1 / Attributable risk

[(a/(a+b)] - [c/(c+d)]

Answer 23

1/Atrributable risk

Question 24

Thrombotic thrombocytopenic purpura

Answer 24

Results from impaired function of vWF cleaving protease, ADAMTS13, resulting in uncleaved vWF multimers that are significantly more prothrombotic and cause diffuse microvascular thrombosis, microa`ngiopathic hemolytic anemia, and thrombocytopenia

Question 25

McCune-Albright Syndrome

Answer 25

Triad of fibrous dysplasia of the bone, endocrine abnormalities, and cafe-au lait spots
Results from an activating mutation in the G-protein/CAMP/AC signaling pathway

Question 26

Musculocutaneous nerve

Answer 26

Innervates the major forearm flexors (biceps brachii, brachialis) and coracobradchialis (flexes and adducts the arm) and provides sensory innervation to the lateral forearm
It is derived from the upper trunk of the brachial plexus (C5-C7) and can be injured by trauma or strenuous upper extremity exercise

Question 27

Polycythemia vera

Answer 27

Myeloproliferative disorder characterized by uncontrolled erythrocyte production
Virtually all patients have a mutation in JAK2, a non-receptor (cytoplasmic) tyrokine kinase associated with the erythropoietin receptor

Question 28

Diabetic ketoacidosis

Answer 28

Urinary acid excretion occurs primarily in the form of NH4 and titratable acids (H2PO4)
In metabolic acidosis, urinary pH decreases due to increased excretion of free H, NH4, and H2PO4
Bicarb is completely reabsorbed from the tubular fluid in acidotic states

Question 29

Graves’ ophthalmopathy

Answer 29

High-dose glucocorticoids such as prednisone are used to control severe Graves’ ophthalmopathy
They are helpful in decreasing the severity of inflammation and decreasing extraocular volume
Conventional anithyroid drugs do not improve ophthalmopathy

Question 30

Direct arteriolar vasodilators (hydralazine and minoxidil)

Answer 30

Lower blood pressure but trigger reflex sympathetic activation and stimulate the renin-angiotensin aldosterone axis
This results in tachycardia and edema
To counteract such compensatory effects, these agents are often given in combination with sympatholytics and diuretics

Question 31

Analysis of variance (ANOVA)

Answer 31

Used to determine whether there are any significant differences between the means of 2 or more independent groups

Question 32

Pancreatic cancer

Answer 32

A palpable but nontender gallbladder (Courvoisier sign), weight loss, and obstructive jaundice (associated with pruritis, dark urine, and pale stools) are indicative of an adenocarcinoma at the head of the pancreas compressing the common bile duct
SMOKING is the most environmental important risk factor

Question 33

Subclavian steal syndrome

Answer 33

Occurs due to severe stenosis of the proximal subclavian artery which leads to reversal in blood flow from the contralateral vertebral artery to the ipsilateral vertebral artery
Patients may have symptoms related to arm ischemia in the affected extremity (exercise induced fatigue, pain, paresthesias) or vertebrobasilar insufficiency (dizziness, vertigo)

Question 34

The best method for determining whether a gene is being expressed

Answer 34

Analyze for the presence of its mRNA using a Northern blot

Question 35

Type 2 DM

Answer 35

Due to insulin resistance and relative insulin deficiency
Chronically elevated free fatty acid levels contribute to insulin resistance by impairing insulin-dependent glucose uptake and increasing hepatic gluconeogenesis

Question 36

Afib in chronic aortic stenosis

Answer 36

In patients with chronic aortic stenosis and concentric left ventricular hypertrophy, atrial contraction contributes significantly to left ventricular filling
Loss of atrial contraction due to afib can reduce left ventricular preload and CO sufficiently to cause systemic hypotension
Decreased forward filling of the left ventricle can also result in back up of blood in the left atrium and pulmonary veins, leads to acute pulmonary edema

Question 37

Radial nerve injury

Answer 37

Can occur with repetitive pressure/trauma at the axilla (improperly fitted crutches)
Weakness of the forearm, hard, and finger extensors (wrist drop, absent triceps reflex) and sensory loss over the posterior arm and forearm, dorsolateral hand and dorsal thumb
More distal lesions spare the triceps brachii

Question 38

Niacin

Answer 38

used to treat hyperlipidemia
Increases HDL levels and decreases LDL levels and triglycerides
Niacin causes cutaneous flushing, which is mediated by prostaglandins and can be diminished by pretreatment with aspirin

Question 39

Amphotericin SE

Answer 39

Binds cholesterol to some degree, causing toxicity to human tissues (nephrotoxicity, hypokalemia, hypomagnesemia)

Question 40

Renal artery stenosis (RAS)

Answer 40

Marked unilateral kidney atrophy
Occurs in elderly individuals due to atherosclerotic changes in the arterial intima or in women of childbearing age due to fibromuscular dysplasia
Hypertension and an abdominal bruit are often present

Question 41

A moderately elevated alkaline phosphatase of unclear etiology should be followed up with

Answer 41

Y-glutamyl transpeptidase

Question 42

Delusional disorder

Answer 42

Characterized by >1 delusion in the absence of other psychotic symptoms
Behavior is not obviously bizarre and functioning is not significantly impaired apart from the direct impact of the delusions

Question 43

Renal angiomyolipoma

Answer 43

benign tumor composed of blood vessels, smooth muscle, and fat
Bilateral renal angiomyolipomas are associated with tuberous sclerosis, an AD condition, will also get subependymal hamartomas in the brain, cardiac rhabdomyomas, facial angiofibromas, leaf-shaped patches of skin lacking pigment (ash-leaf pathces)

Question 44

Thromboangiitis obliterans (Buerger’s disease) is usually seen among heavy cigarette smokers with onset before age 35

Answer 44

Associated with hypersensitivity to intradermal injections of tobacco extracts
Segmental thrombosing vasculitis often extends into contiguous veins and nerves, encasing them in fibrous tissue

Question 45

Class IA antiarrhythmics (quinidine, procainamine, disopyramide)

Answer 45

Sodium channel-blocking agents that depress phase 0 depolarization
They also prolong repolarization due to moderate potassium channel-blocking activity, increasing action potential duration in cardiac myocytes

Question 46

Pure red cell aplasia

Answer 46

Rare form of marrow failure characterized by severe hypoplasia of marrow erythroid elements in the setting of normal granulopoiesis and thrombopoiesis
Pure red cell aplasia is associated with thymoma, lymphocytic leukemias, and parvovirus B19 infection