pathophysiology Flashcards
diet supplement to improve homocysteinuria
B6 (homocysteinuria is often a deficiency of cystathionine synthetase, which requires pyridoxine as a cofactor)
viral phenotypic mixing
co-infection of a host cell by two viral strains resulting in progeny virions that contain nucleocapsid proteins from one strain and the genome of the other. No change in genome so progeny will revert to original, unmixed phenotypes
urethritis, conjunctivitis, arthritis
triad of reactive arthritis (type of spondyloarthropathy)
-symptoms manifest following a primary infection
2 sequelae of subarachnoid hemorrhage
rebleeding secondary vasospasm (prevent with nimodipine)
why do kids squat when they have tetralogy of fallot
squatting cuts off some of the circulation to legs which increases resistance in left heart. The increasing pressure then limits the right to left flow through the VSD.
Eisenmenger syndrome
reversal of shunt to right-left (occurs with increasing pulmonary hypertension that increases right-sided heart pressures that overcome left)
how to tell the difference between myasthenic and cholinergic crisis in pts with myasthenia gravis
administer edrophonium (Tensilon test)
- clinical improvement indicates the pt is undertreated (myasthenic crisis) and meds should be increased
- no improvement indicates cholinergic crisis (too much meds)
coronary steal
phenomenon in which blood flow in ischemic areas is reduced due to arteriolar vasodilation in nonischemic areas
- can lead to hypo perfusion and worsening of ischemia
- drugs like adenosine and dipyramidole
- used in myocardial perfusion imaging to simulate coronary vasodilation induced by exercise
erythema infectosum
fifth disease (parvoviridae)
only non-enveloped, single stranded DNA virus
parvoviridae (fifth disease)
complication of ulcerative colitis presenting with signs of shock
toxic megacolon
- diagnose with X-ray
- risk of perforation
- usually along transverse colon
pulsus paradoxus
decrease in systolic BP greater than 10 with inspiration
- acute cardiac tamponade, restrictive cardiomyopathy
- constrictive pericarditis, severe obstructive lung disease
pro-carcinogens are metabolized into carcinogens by…
cytochrome p450 system (microsomal monooxygenase)
pathogenesis of centriacinar emphysema
chronic, heavy smoking causes release of proteinases, especially elastase, from infiltrating neutrophils and alveolar macrophage
true vs. false diverticuli
true contain all parts of intestinal wall but false don’t have muscle component
- true: meckel’s, appendix
- false: colon diverticuli, Zenker’s
hypoglycemia following prolonged fasting (>24 hrs) with low ketones
think beta-oxidation enzyme deficiency (vs. glycogen storage disorder)
which non-essential amino acid becomes essential in phenylketonuria?
tyrosine (need to supplement)
atypical/malignant phenylketonuria
deficiency of dihydriopterin reductase
- responsible for reduction of BH2 to BH4
- BH4 is a cofactor for many enzymes in tyrosine pathway
silicosis impairs what cell type?
macrophage due to internalized silicon particles
cause of low calcium following blood transfusion
calcium chelation by citrate coagulation in whole blood/packed RBC blood transfusions
cysteinuria defect and only clinical manifestation
- defect of transporter of cysteine, ornithine, lysine and arginine
- chronic nephrolithiasis
3 causes of HIV-associated esophagitis
candida, HSV-1, CMV
pelvic fracture and inability to void in male suggests….
urethral injury, usually at membranous urethra (weakest point)
Foley catheter contraindicated
glomangioma
- benign bluish lesion under the nail bed
- originates from smooth mm. cells that control the thermoregulatory function of dermal glomus bodies
reperfusion injury
paradoxical death of cells via apoptosis or necrosis after blood flow restored
- can cause oxidative damage, cell membrane damage, mitochondrial damage, complement and inflammation
chronic diseases associated with amyloidosis
AL - multiple myeloma. nephrotic syndrome
AA - RA, IBD, spondyloarthropathy
ligating the inferior thyroid artery can damage which nerve?
recurrent laryngeal nerve
most common cardiac defect in Down’s
endocardial cushion defects
special types of necrosis
liquefactive = CNS fat = acute pancreatitis caseous = TB
most common tumor of pineal gland
germinoma
- kids/adolescents, males more
- precocious puberty, impaired upward gaze, possible obstructive hydrocephalus all due to mass effect
test for hereditary spherocytosis
osmotic fragility test (do RBCs lyse in hypotonic soln?)
fundoscopy for diabetic retinopathy
“cotton wool” exudates, retinal hemorrhages, new vessel formation
2 tumors of cerebellum
medulloblastoma and pilocytic astrocytoma
superior vena cava syndrome
MOA: obstruction of SVC that impairs blood drainage from head
S/S: swelling of face/neck, dilated collateral vv., elevated ICP possible
- medical emergency
heteroplasmy
coexistence of both mutated and wild type versions of mitochondrial genomes in an individual cell
holosystolic murmur that increases with inspiration
tricuspid regurgitation (more venous return causes increase with inspiration)
CREST syndrdome
type of scleroderma
Calcinosis, Raynaud, Esophageal dysmotility, Sclerodactyly, Telangiectasia
toe gangrene, renal failure following invasive procedure
artheroembolic renal disease (cholesterol crystals in arteriole lumen)
myxomatous degeneration
pathological weakening of connective tissue
- associated with Marfan’s, aortic aneurysms, mitral prolapse
alpha-1 antitrypsin deficiency associated with
panacinar emphysema DON’T SMOKE
MOA alpha-1 antitrypsin deficiency
A1AT main role is to protect lungs from neutrophil elastase (breaks down elastase, also found in alveolar macrophage)
pathophysiology of tertiary syphilis aneurysm
obliterative endarteritis of the vasa vasorum
CD55/59 deficiency on RBC venous thrombosis (ie: hepatic vein) pancytopenia
paroxysmal nocturnal hemoglubinuria
MOA: complement-mediated RBC lysis due to impaired GPI anchor for decay-accelerating factor that protects RBC membrane from compliment)
tx: eculizumab
porcelain gallbladder
diffuse gallbladder calcification
- usually an incidental finding
- 11-33% will develop gallbladder carcinoma
- recommend cholecystectomy
thalamic syndrome
total sensory loss (not motor) on contralateral side of body
hydrocele MOA
MOA: incomplete obliteration of processus vaginalis forming a connection between scrotum and abdominal cavity that allows for fluid leakage
mechanism of panic attacks
hyperventilation causes decreased PCO2, hypercapnia causes vasoconstriction and decreased cerebral blood flow (dizziness, weakness, blurred vision)
how to tell in an elevated alk phos is of bony or liver origin
follow up with gamma-glutamyl transpeptidase (GGTP)
- will be elevated if biliary/liver origin
hemiballism occurs due to a lesion where?
contralateral subthalamic nucleus (often due to lacunar strokes)
origin of small cell lung tumors
neuroendocrine (will stain for neuroendocrine markers)
murmur heard with intracardiac shunt
splitting of S2 (no change with respiration)
solvent that can inactivate enveloped viruses
ether
pathophys of Janeway lesions
emboli of fragments of infected intracardiac vegetations
enzyme to screen for carcinoid tumors
5-hydroxyindoleacetic acid (breakdown product of serotonin)
scotoma
area in visual field that is diminished
central or arcuate (arc shape)
due to lesions on macula
ectopy definition
microscopically and functionally normal tissue found in an abnormal location due to embryonic maldevelopment (i.e.: Meckel’s)
recurrent pulm/sinus infections
ataxia
telangectasias
ataxia-telangiectasia (defect in ATM gene responsible for repairing double strand DNA breaks)
MOA stable vs unstable angina vs prinzmental
stable: fixed plaque occluding >75% of coronary a. lumen
prinzmetal: vasospasm
unstable: ulcerated plaque with partially obstructive thrombus
increased activity of what enzyme may contribute to colon adenocarcinoma
COX-2 (over expression)
hemoglobin S aggregates in which conformation
deoxygenated/taut form (curve shifted to right)
pathophysiology of nondestructive fibrinous vegetations on cardiac valve cusps
nonbacterial thrombotic endocarditis (NBTE)
-hypercoagulability caused by procoagulant effects of circulating products of cancers
red neurons
first microscopic change following ischemic brain injury
- 12-24 hours
- will be phagocytized by macrophage
pathophysiology of diabetic mononeuropathy
ischemic nerve damage
- in CNIII damage, peripheral nerve is spared, core damaged so motor function impaired but not pupillary size and reactivity
heart problems associated with carcinoid syndrome
right-sided valvular heart disease (tricuspid, pulmonary)
free air in the biliary tree
fistula forms between gallbladder and small intestine
- can lead to obstruction of ileoceccal valve
serum autoantibodies highly specific for RA
anti-cyclic citrullinated peptides (rheumatoid factor is not specific)
vitamin deficiency that mimics Friederich ataxia
vitamin E
pulsus paradoxus
seen with cardiac tamponade
- drop of > 10 mmHg on inspiration
- radial pulse disappears with inspiration
structure commonly injured in anterior or posterior dislocations of knee
popliteal artery (tibial nerve more likely injured with tibial fracture)
skin condition associated with celiac disease
dermatitis herpatiformis
heart problems in DiGeorge
great vessel defects: persistent truncus arteriosus, Fallot, interrupted aortic arch
most common cause of death from MI before hospitalization
ventricular fibrillation precipitated from ischemia
most common cause of death from MI in hospital
ventricular failure/contractile dysfunction
most common cardiac manifestation of SLE
pericarditis (sharp pleuritic pain relieved by leaning forward)
medulloblastoma vs pilocytic astrocytoma on imaging
medulloblastoma is solid but pilocytic astrocytoma is solid and also cystic
S. bovis endocarditis is associated with….
colon cancer
kidney stones that are radiolucent
uric acid stones (all others radioopaque), use ultrasound to visualize
where do clear cell carcinomas originate?
epithelial cells of proximal renal tubule
ezcema
thrombocytopenia
recurrent infections
Wiskott-Aldrich syndrome
- X-linked
- tx: bone marrow transplant
order of cardiac AP velocity (fastest to slowest)
“Park AT VENTura Avenue”
Purkinji system, atrial mm., ventricular mm., AV node
cell type that prevents hematologic spread of candida
neutrophils (T cells responsible for fighting local infection only)
myotonia (abnormally slow relaxation)
frontal baldness
cataracts
testicular atrophy
myotonic dystrophy
- CTG repeat expansion
- abnormal expression of myotonin protein kinase
AML vs ALL (stains)
AML: auer rods stain positive for myeloperoxidase
ALL: TdT
psammoma bodies
papillary CA of thyroid
meningioma
mesothelioma
serous endometrial CA
nerve commonly injured during thyroidectomy
superior laryngeal (innervates cricothyroid mm.)
renal papillary necrosis diseases
“SAAD papa”
- Sickle cell disease/trait, Analgesics, Acute pyelo, DM
- from ischemia, causes hematuria
S-100 positivity
tumors of neural crest origin (melanoma, schwanomma, etc.)
proto-oncogene examples
ras, ERB, N-myc, abl (anti-oncogenes: Rb, WF-1, p53, APC, BRCA)
3 ways to get Down’s
- meiotic nondisjunction
- unbalanced Robertsonian translocation
- mosaicism
BRAF mutation
melanoma (signaling pathway for melanocytes)
dysthymic disorder
less severe than major depressive disorder
- only 4 or fewer symptoms present (> 5 for MDD)
- must be present at least 2 years
uptake of promodeoxyuridine indicates…
high grade in brain tumor (reflects number of cells in S phase - preparing to divide)
first area damaged by global cerebral ischemia
hippocampus (pyramidal cells) followed by purkinje cells of cerebellum
chronic diarrhea
bacterial and viral infections
mucocutaneous candidiasis
SCID
parinaud syndrome
paralysis of conjugate vertical gaze due to lesion in superior colliculi (ie: pinealoma), upward gaze palsy