uworld assessment block #4 4.15 Flashcards
infectious arthritis causes? presentation
most common (1) n. gonorrhea (disseminated). can also be (2) s. aureus (2) streptococcus
STD triad: synovitis (arthralgia, knee), tenosynovitis (hand), dermatitis
(note, no eye symptoms. compared to reiter’s – conjunctivitis)
differentiate infectious arthritis from reactive arthritis ‘reiter’s’
infectious agents:
infectious arthritis: gonorrhea, s. aureus, strep
reactive arthritis: nongonococcual urethritis (chlamydia) and GI bugs (campylobacter, salmonella, shigella, yersinia)
eye involvement:
infectious: tenosynovitis, synovitis, dermatitis
reactive: conjunctivitis, seroneg arthritis, urethritis
viral arthritis
symmetric polyarticular disease. associated w/ parvovirus, hep B, hep C, rubella, alphavirus
prader-willi presentation
neonatal hypotonia, extreme hyperphagia, morbid obesity, ultimately DM type II, short, small hands & feet, hypogonadism, characteristic facies.
pathophysiology of prader-willi
imprinting.
normal: mom’s gene 15q11 region SILENT. express ONLY PAPA.
disease:
(1) delete papa’s gene
(2) 25% uniparental disomy (only inherit mom’s imprinted gene)
would detect microdeltion of papa’s chr 15 on FISH. if FISH is normal = uniparental disomy.
pathophysiology of angelman’s syndrome
imprinting
normal: papa’s gene is normally SILENT. express ONLY MOM.
disease:
(1) delete mom’s gene
(2) 5% uniparental disomy. (only inherit papa’s imprinted gene)
presentation of angelman’s syndrome
inappropriate laughter “happy puppet”, seizure, ataxia, severe intellectual disability
paracentric inversions
inversions of chromosomal DNA in one arm of chromosome not including centromere
GI presentation of celiac’s disease
(1) blunting of villi (2) lymphocytes in lamina propria (3) hyperplasia of crypts
CD8+ T cells infiltrate surface epithelilum, while CD4+ in lamina propria.
distal duodenum
Ab found in celiac’s disease
anti-transglutaminase, anti-gliadin, anti-endomysial
presentation of dermatitis herpatiformis? pathophysiology?
PRUITIC erythematous urticarial plaques on extensor surfaces of elbow, knee, buttocks, back.
caused by CROSS-REACTION of gliadin IgG and IgA with RETICULIN
–> component of fibrils that anchor the epidermal basement membrane to superficial dermis.
neutrophils at dermal tips –> microabscesses –> subepidermal blisters
normal thickness of right ventricle? left ventricle?
right: 3-4mm
left: 1 cm
layers of epidermis
corneum lucidium granulosum spinosum basale
describe stratum corneum
15-20 layers of dead squamous cells that lack nuclei.
generally thickest in regions exposed to friction (soles of feet)
callus
painless thickening of stratum corneum, at locations of repeated of external pressure / friction
essential characterestics of PCOS
amenorrhea, obesity, hirsuitism, virilization, peripheral insulin resistance, dyslipidemia
ovaries in PCOS
bilateral enlargement and smooth thickened capsules.
subcapsular follicles in diff stages of atresia.
hyperplastic theca stroma cells rim arrested follicles
hormone imbalance in PCOS
elevation in everything EXCEPT FSH
think: high LH makes theca cells produce more androgens.
FSH is diminished, so granulosa cells can’t make as much estrogen.
lesch-nyhan inheritance? presentation?
X-linked recessive.
self-mutilating behavior, mild mental retardation, involuntary movement, delayed motor development, nephrolithiasis, gout
FROST on skin under diaper –> hyperuricuria
rx: allopurinol
HGPRT fxn
purine salvage.
convert hypoxanthine and guanine to inosine monophosphate (IMP) and guanine mono phosphate (GMP).
absence: increased purine synthesis, hyperuricemia, hyperuricuria
ADA deficiency
impt for purine catabolism. deficiency: build up dATP, inhibit ribonucleotide redutase, inhibit DNA synthesis.
adenine phosphoribosyltransferase (APRT)
involved in purine salvage. converts adenine to AMP.
deficiency: hyperuricemia and adenine stone urolithiasis.
autosomal recessive. no neurological symptoms
erythromyocin drug effect
block translocation.
prevent tRNA release from donor site after peptide bond formation. 50S.
chloramphenicol drug effect
bind to 50S
block peptidyltransferase action