5/24 Mixed Flashcards
Wilson’s Disease
Can cause cystic degeneration of the putamen as well as damage to other basal ganglia structures.
The putamen is located medial to the insula and lateral to the globus pallidus on coronal sections.
Pseudogout
Rhomboid-shaped calcium pyrophosphate crystals
Positively birefringent under polarized light
Knee joint is involved in >50 % of cases
Hereditary Angioedema
Low serum levels of C1 esterase inhibitor
AD, episodes of painless, non-pitting, well-circumscribed edema (face, neck,lips, tongue), respiratory obstruction, abdominal pain, vomiting, diarrhea
activated kallikrein and bradykinin levels are increases
Bradykinin, C3a, and C5a mediate angioedema by increasing vasodilation and vascular permeability
SE of ACEi = angioedema (bradykinin accumulation)–ACEi are CONTRAINDICATED in patients with hereditary angioedema
Teratogenic Medications: Phenytoin
Neural tube defects, orofacial clefts, microcephaly, nail or digit hyperplasia
Teratogenic Medications: Lithium
Ebstein anomaly, nephrogenic diabetes insipidus, hypothyroidism
Teratogenic Medications: Valproate
Neural tube defects
Teratogenic Medications: Isotertinoin
Microcephaly, thymic hypoplasia, small ears, hydrocephalus
Teratogenic Medications: Methotrexate
Limb and craniofacial abnormalities, neural tube defects, abortion
Teratogenic Medications: ACE inhibitors
Renal dysgenesis, oligohydramnios
Teratogenic Medications: Warfarin
Nasal hypoplasia, stippled epiphysis
MOA of penicillins and cephalosporins
Irreversibly bind to penicillin-binding proteins such as TRANSPEPTIDASES
Long term treatment of Parkinson disease with levodopa
Complicated by periodic and sometimes unpredictable fluctuations in motor function
This “on-off” phenomenon is thought to be a consequence of progressive nigrostriatal neurodegeneration leading to a decreased therapeutic window for levodopa
SE Dihydropyridine Ca Channel Blockers (Amlodipine)
Headache, Flushing, Dizziness, Peripheral Edema
Pituitary Apoplexy
Acute hemorrhage into the pituitary gland
Associated with preexisting pituitary adema
Presents acutely with severe headache, cranial nerve involvement (bitemporal hemianopsia, opthalmoplegia), and signs of meningeal irritation
Pts often have chronic symptoms associated with the underlying pituitary tumor
Cardiovascular collapse can occur due to adrencortical deficiency
Acute pancreatitis
80% due to gallstones and chronic alcoholism
Less common causes account for the other 20%
Inherited or acquired hypertriglyceridemia (>1000) can cause acute pancreatitis
Cryptorchidism
The seminiferous tubules become atrophic and hyalinized as a result of temperature induced damage, resulting in significantly depressed sperm count as well as decreased inhibin levels
Hormonal function of leydig cells is usually not impaired , thus secondary sexual characterisitcs and sexual performance are normal
Should be corrected early in life to prevent damage to ST and decrease risk of testicular cancer
Enveloped viruses
Acquire their lipid bilayer envelope by budding through the plasma membrane of the host cell
Exceptions include the herpesviruses, which bud through the acquire their envelope from the host cell nuclear membrane
Wernicke Encephalopathy
Pyruvate dehydrogenase and a-ketoglutarate dehydrogenase require thiamine as a cofactor
Administration of glucose to thiamine-deficient patients (alcoholics) can result in Wernicke encephalopathy (acute confusion, opthalmoplegia, ataxia) due to increased thiamine demand
Multiple sclerosis incontinence
Often develop a spastic bladder a few weeks after developing an acute lesion of the spinal cord
These patients present clinically with increased urinary frequency and urge incontinence
Urodynamic studies show the presence of bladder hypertonia
Cleavage of proinsulin
Occurs in the islet cell secretory granules
Yields insulin and C-peptide
Both are stored in the granule until they are secreted in equimolar amounts
Phenotype mixing
Refers to coinfection of a host cell by 2 viral strains, resulting in progeny virions that contain nucleocapsid proteins from one strain and the unchanged parental genome of the other strain
Because there is no change in the underlying viral genomes (no genetic exchange), the next generation of virions revert to their original, unmixed phenotypes
SE of whole/packed blood transfusion (5-6 L)
May develop elevated plasma levels of citrate (a substance added to stored blood)
Citrate chelates calcium and magnesium and may reduce their plasma levels, causing paresthesias
Fracture of the scaphoid bone
Caused by a fall onto an outstretched hand
Exam shows tenderness in the anatomical snuff box
Scaphoid bone is vulnerable to avascular necrosis due to its tenuous blood supply
Structures that enter the orbit via the superior orbital fissure
The oculomotor nerve (CN III), ophthalmic nerve (CN V1), trochlear nerve (CN IV), abducens nerve (CN VI), superior opthalmic vein
Theophylline
Adenosine receptor antagonist and indirect adrenergic agent with a narrow therapeutic index
Predominantly metabolized by hepatic cytochrome oxidases
Inhibition by concurrent illness, or drug (cimetidine, ciprofloxacin, macrolides, verapamil) can raise serum concentration and cause toxicity (seizures, cardiac arrhythmias)
MHC II processing
MHCII expressed on the surface of APC and function to present antigen that is foreign
Antigen is taken into the APC by phagocytosis or endocytosis and is loaded onto MHC II within ACIDIFIED endosomes and the MHC II protein-antigen complex is then expressed on the cell surface for subsequent interaction with T lymphocytes
Failure to acidify lysosomes would lead to deficient expression of MHC II bound to foreign antigen and subsequent lack of interaction between APCs and T cells
Effects of epinephrine on insulin secretion
Alpha-2 adrenergic receptors inhibit insulin secretion
Beta-2 adrenergic receptors stimulate insulin secretion
The alpha 2 mediated inhibitory effect is generally predominant, causing sympathetic stimulation to lead to overall inhibition of insulin secretion
Following pretreatment with an alpha 2 receptor blocker, epinephrines effect on beta-2 receptors would become dominant, resulting in increased insulin secretion
Cyanide Toxicity
Can occur in patients treated with nitroprusside
Cyanide toxicity presents with altered mental status, seizures, cardiovascular collapse, lactic acidosis and bright red venous blood
Antidotal treatment of cyanide toxicity can be achieved by 3 different strategies:
1) direct binding of cyanide ions (hydroxocobalamin)
2) induction of methemoglobinemia (sodium nitrite)
3) Use of detoxifying sulfur donors (sodium thiosulfate)
First line treatment for major drepessive disorder that does not cause sexual dysfunction
Bupropion (norepinephrine dopamine reuptake inhibitor)
Atropine
Indicated for the treatment of bradycardia as it decreases vagal influence on the SA and AV nodes
Common side effect is increased intraocular pressure
It may precipitate acute closed angle glaucoma in susceptible individuals
A benign glomus tumor (glomangioma)
Very tender, small, red-blue lesion under the nail bed
Originated from the modified smooth muscle cells that control the thermoregulatory functions of dermal glomus bodies
IgA nephropathy (Berger disease)
Presents as recurrent, self-limited, painless hematuria within 5 days of an upper respiratory infection
Kidney biopsy will show mesangial IgA deposits on immunofluorescence
Vitamin E deficiency
Lipid soluble vitamin with antioxidative properties
Neurologic symptoms closely mimic Friedreich ataxia and include ataxia (degeneration of spinocerebellar tracts), loss of position and vibration sense (degeneration of dorsal columns), loss of deep tendon reflexes (peripheral nerve degeneration)
Which part of the loop of Henle is impermeable to water
Loop of Henle
Congenital Hypothyroidism
Most common cause of preventable intellectual disability
Most cases due to thyroid dysgenesis
T4 is responsible for stimulation of protein synthesis and carbohydrate/lipid catabolism in many cells
Asymptomatic at birth (maternal T4), lethargy, poor feeding, constipation, hypotonia, umbilical hernia, protruding tongue, large anterior fontanelle
Inferior wall of the heart
The inferior wall of the left ventricle forms most of the inferior (diaphragmatic surface of the heart) and is supplied by the POSTERIOR DESCENDING ARTERY
IN 85%-95% of individuals, the posterior descending artery derives from the right coronary artery
Timolol for open-angle glaucoma
Timolol and other non-selective beta blockers work by diminishing the secretion of aqueous humor by the ciliary epithelium
Acetazolamide for open angle glaucoma
A carbonic anhydrase inhibitor
Decreases aqueous humor secretion by ciliary epithelium
Prostaglandin F2a (Latanoprost, Travoprost) and Cholinomimetics (Pilocarpine, carbachol) for open angle glaucoma
Decrease intraocular pressure by increasing the outflow of aqueous humor
G6PD Deficiency
Glucose-6-Phosphate —> 6-Phosphogluconate
Testicular germ cell tumors or gestational trophoblastic disease
May develop very high serum hCG concentrations
hCG has a structure similar to TSH, hCG can stimulate TSH receptors and cause hyperthyroidism
Cheyne-Stokes breathing
Cyclic breathing in which apnea is followed by gradually increasing then decreasing tidal volumes until the next apneic period
Commonly seen in the setting of advancer CHF
Postpartum hemorrhage
Bilateral ligation of the internal iliac artery can decrease uterine blood flow and control postpartum hemorrhage that is unresponsive to medical management (uterine massage, uterotonic meds)
Reactive arthritis
Spondyloarthropathy associated with HLA-B27 that can occur following infection with Chlamydia, Campylobacter, Salmonella, Shigella, Yersinia
Presents with sterile arthritis due to deposition of immune complexes
E. coli
80% of UTIs
P fimbrae are the most important virulence factor
Motile gram negative rods, demonstrating green metallic sheen on eosin methylene blue (EMB) agar and hemolysis on blood agar
Spleen
SYSTEMIC BACTERIAL CLEARANCE
Acts as a blood filter capable of removing circulating pathogens and as a major site of opsonizing antibody synthesis. Asplenic patients are prone to infections caused by encapsulated organisms
Urge incontinence/ overactive bladder
Caused by uninhibited bladder contractions (detrusor instability)
Rx: antimuscarinic drug (targeting M3 receptors)
Health promotion
Process of enabling people to increase control over their health and its determinants and thereby improve their health
Central retinal artery occlusion
Sudden, painless, PERMANENT monocular blindness
Fundoscopic exam reveals a pale retina and a “cherry-red macula”
Potency of an inhaled anesthetic
The minimal alveolar concentration (MAC) is a measure of the potency of an inhaled anesthetic. It is the concentration of the anesthetic in the alveoli that renders 50% of patients unresponsive to painful stimuli (ED50). Potency is inversely proportional to the MAC: the lower the MAC, the more potent the anesthetic
Negative selection in T cell maturation
Essential for eliminating T cells that bind to self MHC or self antigens with overly HIGH AFFINITY
Occurs in the thymic MEDULLA
Pilocytic astrocytoma
Most common brain tumor in children Low grade neoplasms, arise from astrocytes Have both a CYSTIC and SOLID component Cerebellum is most common location Rosenthal fibers
Enterococci endocarditis
Enterococcus is component of the normal colonic and urogenital flora, capable of growing in hypertonic saline and bile, gamma-hemolytic, catalase-negative, pyrrolidonyl arylamidase-positive.
GU INSTRUMENTATION OR CATHETERIZATION has been associated with entercoccal endocarditis
Osteoporosis lab values
In primary osteoporosis, serum calcium, phosphorous, and PTH levels are typically in the NORMAL RANGE
