UWorld I Flashcards
Acute respiratory distress syndrome
Hypoxemia and bilateral pulmonary infiltrates lead to injury to alveolar pneumocystis and endothelial damage - hyaline membranes form, diminished surfactant production (alveolar collapse), and increased capillary permeability
Cardiac tissue conduction velocity
Fast - Purkinje –> Atrial muscle –> Ventricular muscle –> AV node - Slow. Park at venture avenue
Osteosarcoma
A/w pager’s disease of bone
Vitamin A (retinol)
Teratogenic - microcephaly, cardiac anomalies, growth retardation, and spontaneous abortion.
Ribavirin
Inhibits viral RNA polymerase - chronic Hep C or RSV
DNA laddering
DNA fragments of 180 BP = apoptosis. Endonuclease cleave DNA during karryhorexhis. Absence of BCL-2 = inhibited apoptosis. No DNA laddering suggests malignancy.
M3 receptors
Stimulates Gq in bronchial smooth muscle –> IP3 –> increased intracellular Ca2+ –> Bronchoconstriction
Atropine
Cholinergic antagonist - Over dose –> Hot as a hare, mad as a hatter, blind as a bat, red as a beet, dry as a bone
Cholinergic toxicity
DUMBELLS - Diarrhea, urination, mitosis, bradycardia, emesis, lacrimation, lethargy, salivation
Acute promyelocytic leukemia
Auer rods
(15:17) translocation
15 = promyelocytic leukemia gene.
17 = retinoic acid receptor.
Sx: Pancytopenia (weakness, fatigue, infections, gingival bleeding) and DIC
Tx: All trans-retinoid acid
(8:14)
Burkitt lymphoma - Starry sky + EBV
8 = c-myc
14 = Ig Heavy chain
(12:21)
Childhood B cell acute lymphocytic leukemia
Anemia, thrombocytopenia, lymphoblasts
(14:18)
Follicular lymphoma
14 = Ig heavy chain
18 = BCL-2 (inhibits apoptosis)
IL-2
Produced only by T cells
Stimulates growth and differentiation of B cells, T cells, macrophages, and NK cells.
Can promote FAS mediated apoptosis
TNF-alpha
Systemic inflammatory response - e.g. septic shock and cachexia
Interferon-alpha
antiviral
Cadherins
Bind epithelial cells together, calcium dependent - loss of calcium –> loss of cell-cell adhesion
Molluscum contagiosum
Caused by Poxvirus
Eosinpohillic cytoplasmic inclusion bodies
Anterior/posterior knee dislocation
Injury to popliteal artery
Postpartum endometritis
A/w C-section
fever, leukocytosis, uterine tenderness, foul-smelling discharge.
NNT
NNT=1/ARR
ARR = control group event rate - experimental group event rate
DKA
Metabolic acidosis, ketonemia, hyperglycemia, hyperkalemia, hyponatremia.
Everything high EXCEPT sodium - being peed out
Dandy walker formation
Absence of cerebellar vermis - 4th ventricle enlargement
Phenoxybenzamine
Prior to pheochromocytoma removal
Long active alpha-blocker
Isoproteronol
Non-selective beta-agonist (increases beta-1 effects on heart –> increase HR) used for bradycardia and heart block
Phenylephrine
Alpha agonist - decongestant and vasopressor in severe hypotension
Germinal matrix hemmorrhage
Intraventricular hemorrhage - premature infants less than 32 weeks at greatest risk
Cisplatin
Ototoxic
Amiodarone
Interstitial pneumonitis
slowly progressive dyspnea and productive cough
Aspirin sensitivity
Cox blockade –> increased leukotrienes and bronchoconstriction. Leukotrienes are pro-inflammatory
Allelic heterogeneity
different mutations in the same locus cause similar phenotypes
Leukotriene D4
Bronchial asthma pathogenesis - induces bronchospasm and increases bronchial mucus secretion.
Monteleukast is a D4 antagonist
FGFR3 gain of function
achondroplasia
Bruton tyrosine kinase
x-linked agammaglobulinemia - on X-chromosome
B cells can’t leave marrow, no Ab’s produced.
Recurrent respiratory tract bacterial infections in infants.
Normal T cells, absent B cells (less that 1% CD19 or CD20)
Chromosome 7
CF, ehlers-danlos, osteogenesis imperfecta
Chromosome 16
polycystic kidney disease, tuberous sclerosis
Chromosome 20
Maturity onset diabetes of the young
Chromosome 22
DiGeorge
N-terminal peptide sequence
signals protein for Rough ER
Deficiency results in cytosolic protein accumulation
MSUD
Defect in branched chain alpha keto acid dehydrogenase
Branched chain amino acids (leucine, isoleucine, and valine) accumulate in urine and blood –> CNS toxicity and maple syrup smelling urine.
Sx: Poor feeding and vomitting
Tx: restrict branched chain amino acids in diet (leucine, isoleucine, valine). Supplement diet w/ thiamine (B1)
Biotin
Cofactor for carboxylation enzymes - e.g. acetyl coA decarboxylase and pyruvate carboxylase.
Androgen binding protein
Keeps testosterone level high in seminiferous tubules. secreted by sertoli cells in response to elevated FSH.
Normal plasma levels of testosterone indicate that Lydia cells are working, low testosterone ONLY in seminiferous tubules indicates sertoli cell (ABP) dysfunction.
phentolamine
alpha-1 blocker
PAS positive granules
Whipple’s disease
Crypt abscesses + pseudopolyps
Ulcerative colitis
Cobblestone mucosa + transmural inflammation
Crohn’s
Ischemic colitis
Evidence of CAD or PAS (e.g. decreased peripheral pulses or h/o angina)
Mucosal hemorrhage and patchy necrosis
Early onset OA + thin sclerae
Osteogenesis imperfecta
Defect in Type I collagen
Protooncogenes
RAS - GTP binding protein - cholangiocarcinom and pancreatic adenocarcinoma
MYC - Transcription factor - Burkitt lymphoma (8:14)
ERB/EGFR - Receptor tyrosine kinase - lung adenocarcinoma
ERBB2/HER2 - Receptor tyrosine kinase - breast
ABL - non receptor tyrosine kinase - CML (9:22 BCR;ABL)
BRAF - Ras signal transduction - Hairy cell, melanoma
Tumor suppressor genes
BRCA - DNA repair
APC - WNT signaling - FAP/colon cancer
TP53 - Genome stability - most cancer, li-fraumeni
RB - G1–>S inhibitor - retinoblastoma, osteosarcoma
WT1 - urogenital differentiation - wilms tumor
VHL - Ubiquitin ligase component - RCC, VHL syndrome
Ocreotide
Treatment of carcinoid syndrome. A somatostatin analog that reduces the secretion of bioactive peptides.
Wide split fixed S2
ASD
Achalasia
Absence of esophageal peristalsis in distal esophagus and hypertensive LES that can’t relax. Results in dilated esophagus with distal narrowing
Picornaviridae
(+) ssRNA
Enteroviruses - most common cause of viral meningitis
Paramyxoviruses
(-) ssRNA
Measles, mumps, RSV
Coronavirus
(+) ssRNA
Common cold
Calcivirus
(+) ssRNA
Norovirus - gastroenteritis
Arenavirus
(-) ssRNA
Lassa virus - hemmorrhagic fever virus from rodent urine inhalation
Prader-will/angelman
Prader will - maternal uniparental disomy OR loss of parental gene. LOSS of paternal
Angelman - Paternal uniparentla disomy OR maternal loss of gene. LOSS of maternal
Callous
Thickening of stratum corneum - outermost layer
Fabry
X-linked recessive
Deficient: alpha-galactosidase
Clinical presentation: angiokeratomas, peripheral neuropathy, glomerulopathy
Tay-sachs
AR
Deficient in beta-hexosaminidase A
Macular cherry red spot, progressive neurodegeneration
Gaucher
AR - Most common lysosomal storage disorder
beta-glucocerebrosidase
Hepatosplenomegaly, pancytopenia, bon pain/osteopenia
Niemann-pick
AR
Sphingomyelinase deficient
Macular cherry red spot, progressive neurodegeneration, heptaosplenomegaly (differentiates neumann pick from tay-sakcs, hexosaminidase deficiency w/o HSM)
Krabbe
AR
galactocerebrosidase deficient
Progressive neurodegeneration, peripheral neuropathy, optic atrophy
Metachromatic leukodystrophy
AR
Arylsulfatase A
Progressive neurodegeneration, peripheral neuropathy
FSGS
Nephrotic syndrome, most common. Often caused by HIV
Vitamin D supplementation
Increases intestinal absorption of phosphate and calcium, the rise in serum calcium inhibits PTH