UWorld QBank - 2nd round - part 3 Flashcards
How are the attachments of the cruciate ligaments positioned in a sagittal anterior view of the right knee for example?
ACL - goes from lateral condyle of femur towards the medial condyle of the tibia
PCL - goes from media condyle of femur towards lateral condyle of tibia
What is reverse T3 and how would levels be affected in primary hypothyroidism that is being treated with T3?
inactive form of thyroid hormone generated from peripheral conversion of T4 (similar to T3, but NOT produced in thyroid)
T3 treatment would increase T3 levels but not T4, therefore rT3 levels would remain low
What are the characteristic serum hormone levels in Klinefelter’s syndrome?
- Consistent elevation of plasma gonadotropins , mainly FSH
- Elevation of estradiol
- Reduction of testosterone
What is transmural inflammation of the arterial wall with fibrinoid necrosis characteristic of? What are the key symptoms and associations of this disorder?
Polyarteritis Nodosa - may occur in all organs except lung
Sx = Fever, Abdominal pain, Peripheral neuropathy, weakness and weight loss
-Associated with Hepatitis B in 10-30% of cases (liver infection)
What is the main complication that can occur with severe aortic stenosis ? (Hint: patient may present with dyspnea)
- patients develop decreased CO, many w/ concentric LV hypertrophy (decreased LV compliance)
- Become dependant on LA contractions and kick to keep normal LV filling
- If A-fib occurs -> LV preload becomes significantly decreased -> Major hypotension -> blood build up in LA and pulmonary veins -> pulmonary edema
What are the differences between a chancre, gumma, and chondyloma lata?
- Chancre - painless ulceration w/ raised indurated borders in primary syphilis (1-3 weeks post contact, resolves some weeks after)
- Chondyloma lata - large, gray wart-like growths in genital or perianal region in secondary syphilis (hand and feet rash)
- Gummas - painless indurated granulomatous lesions -> progress to white-gray rubbery lesions that may ulcerate in TERTIARY syphilis (years post infection, look for Neuro signs, tabes dorsalis or aortic aneurysm)
What neurovascular bundle sits above the thyroid gland and lateral to the thyroid cartilage? What will damage here cause?
Superior laryngeal artery and vein and Superior laryngeal nerve (at risk of damage during thyroidectomy)
-Damage would cause denervation of the cricothyroid muscle (all other laryngeal muscles innervated by recurrent laryneal nerve)
What is the most common recurrent complication following reactivation of VZV in the thoracic dermatome? Cranial dermatome?
Post-herpetic neuralgia - stabbing, intermittent pain lasting for months potentially (chances of having pain increase with age)
VZV infection of trigeminal ganglion -> Herpez zoster ophthalmicus -> visual impairment
What leads to elevations of CD4+ cells in bronchoalveolar lavage fluid? CD8+?
CD4+ - sarcoidosis
CD8+ - Hypersensitivity pneumonitis
What are the major adverse effects of succinylcholine?
- Malignant hyperthermia in susceptible patients
- Severe hyperkalemia (in patients with burns, myopathies, crush injury and denervation)
- Bradycardia (PANS stimulation) or Tachycardia (SANS ganglion effects)
What diseases are associated with MEN1?
- Pituitary Adenoma (prolactin, CTH)
- Parathyroid tumor (hypercalcemia)
- Pancreatic Tumor (which is gastrin secreting 70% of time -> zollinger ellinson syndrome; also can have insulinoma, and VIPoma)
What pathology findings are consistent with liver cirrhosis? Chronic viral hepatitis?
Cirrhosis = nodular regeneration CVH = Periportal fibrosis
From which cells does renal cell carcinoma originate from?
Proximal renal tubules
What conditions precipitate uric acid stone formation?
Low pH (uric acid is soluble at physiologic pH), and the lowest pH is at the collecting ducts
What is pretibial myxedema?
Lower leg skin thickening and induration (classically like an orange peel), which is a late manifestation of Grave’s disease (this is the autoimmune response to TSH receptor, like exophthalmia)
What occurs during the maintenance and recovery phase following acute tubular necrosis?
Maintenace (1-3days) - oliguria -> fluid overload, increased BUN/Cr, HyperK+, high anion gap metabolic acidosis (H+ retention), Muddy brown casts, high FeNa+
Recovery - Vigorous diuresis (w/ poor functioning tubular cells) -> Hypokalemia, Mg, PO4 and Ca (Hypokalemia being most serious complication)
Which drugs are selective arteriolar vasodilators and what are their main side effects?
Hydralazine and Minoxidil (lower blood pressure, good for patients refractory to other meds)
SE: Reflex Tachycardia and Edema (Selective arteriolar vasodilation -> significant vasodilation and reduction in arterial pressure -> Reflex SANS activation via baroreceptors -> Increased HR, contractility and increased RENIN activity -> Na+ and Fluid retention - give these drugs with sympatholytics and diuretics)
Which drugs provide decreased mortality risk benefit for CHF?
Spirinolactone and Carvedilol (along w/ other beta-blockers, but this is best for CHF) - Carvedilol is nonspecific and has effects on beta1, 2 and alpha 1 (introduce slowly to avoid exacerbation of CHF, do not use in unstable CHF)
What is Milrinone?
Phosphodiesterase inhibitor, increases cardiac contractility and decreases preload and afterload. Can only be given via IV, so used in short term therapy (some studies have shown increased mortality with CHF)
How may enterococci develop resistant to aminoglycosides (e.g. Gentamicin)?
Aminoglycoside-modifying enzymes on cytoplasmic membrane surface that transfer different chemical groups (acetyl, adenyl, phosphate) to the antibiotic -> decreasing ability of drug to bind ribosomes
How do VREs gain resistance against vancomycin?
Acquired resistance mediated by plasmids/transposons -> proteins synthesized that act as ligases that alter D-ala-D-ala cell-wall precursors (e.g. to D-ala-D-lactate), which are targets of vancomycin
What is a precursor to NAD+?
Tryptophan
What is arginine a precursor for?
NO, Urea, ornithine, agmatine, and necessary to form creatine
How do eosinophils participate in parasitic defense?
Stimulated by IL5 from Th2 and Mast cells -> Fc receptors on Eo surface bind IgG and IgE coated parasites -> triggers degranulation of cytotoxic proteins (e.g. Major Basic Protein) and reactive oxygen species (this is antibody mediated cell cytotoxicity)
What is subacute granulomatous (de Quervain’s) thyroiditis?
-Occurs following viral infection
-Tenderness over thyroid gland, Increased ESR, and markedly reduced iodine uptake by thyroid
-Thyrotoxicosis from release of stored thyroid hormone, secondary to thyroid inflammation (new hormone is not formed)
Biopsy: Initial PMN infiltration followed by lymphocytes, histiocytes, and multi-nucleated giant cells which surround fragmented colloid
What are the presenting signs of congenital hypothyroidism?
Sx: Lethargic, poor feeding, prolonged jaundice, constipation, muscle hypotonia and a hoarse cry.
Physical: Pale, dry, cool skin, myxedema and macroglossia. Coarse facial features and umbilical hernia. Increased incidence for ASD/VSD
Will develop irreversible mental retardation (from low T4) if not screened and treated early
What is actinomycosis? Which patients are prone to get it, and what are the signs and sx of it?
Slowly progressive disease of gram+ anaerobic bacteria (actinomyces israelli)
-Often in patients with dental caries and poor dentition and alcoholics.
Sx: Pulmonary signs from aspiration (yellow sputum, coarse ronchi, apical lobe consolidation)
Biopsy: filamentous branching patterns and sulfur granules
Which portacaval anastamoses leads to the development of esophageal varices? Caput medusae? Hemorrhoids?
EV: Left gastric vein (portal circulation) and esophageal vein (systemic circulation)
CM: Paraumbilical veins and Superficial/inferior epigastric vessels
Hem: Superior rectal vein and Middle/inferior rectal veins
What conditions lead to renal papillary necrosis? What is the usual presentation?
Multiple systemic conditions causing ischemia:
-Sickle cell disease/trait, analgesic nephropathy (NSAIDs), Diabetes mellitus, Acute pyelonephritis
Present late in disease with gross hematuria
What is the usual presentation for ischemic tubular nechrosis?
Oliguria in hospitalized severely ill patients. Muddy brown granular casts in urine.
Which enzyme facilitates triglyceride break down? How about use of the byproducts of this reaction?
- Lipase breaks Trigs into glycerol and Fatty acids.
- Fatty acids undergo betaoxidation and ketogenesis
- Glycerol is converted into Glycerol-3P in liver by GLYCEROL KINASE
What is the purpose of the enzyme ATP-citrate lyase?
Converts citrate in the cytoplasm back to oxaloacetate and acetyl CoA