ID II Flashcards
at what time in gestation does toxo have
1) greatest transmission
2) more severe disease to fetus if acquired
1) later in pregnancy (less Ab)
2) earlier (embryopathy)
at what time in gestation does syphillis have
1) greatest transmission
2) more severe disease to fetus if acquired
1) anytime in pregnancy (like CCcmv)
2) later (mom doesn’t get treated, titers are still high - unusual)
at what time in gestation does rubella have
1) greatest transmission
2) more severe disease to fetus if acquired
1) U shaped (U for rubella), early and late
2) earlier (embryopathy)
at what time in gestation does CMV have
1) greatest transmission
2) more severe disease to fetus if acquired
1) anytime in pregnancy (like ssssyphillis)
2) earlier (embryopathy)
what is treatment for toxo
pyremathamine and sulfadiazene for on year
sulfadiazene can cause BM suppression and neutropenia so supplement with folinic acid
what are risk factors for CMV transmission in BM?
higher in PT babies.
decreases with both freezing and thawing of BM
when is SNHL detected in CMV
usually not until one year
when does fetal IgG vs placental transfer begin?
starts production around 10 weeks, pinocytosis and active transport from placenta around 20 weeks and accelerates during 3rd trimester. Levels exceed maternal levels by term.
when should breastfeeding be discouraged in regards to TB?
only during active, untreated TB. If being treated, okay to bf.
when should pregnant women be treated in regards to TB?
if asymptomatic with no additional risk factors - wait until postpartum b/c isoniazid can cause liver failure in fetus
if higher risk (ie exposure), then do INH after first trimester.
always give B6
how do you manage an infant in these situations:
1) mother has latent TB ((+) PPD, neg CXR, asymptomatic OR (+) CXR but asymptomatic)
2) mother has active TB (((+) PPD, (+) CXR, symptoms))
1) treat mother with INH (either after 1st tri or post partum), baby needs nothing additional, allow breastfeeding
2) treat mother with full regimen, baby needs testing, if (+) treat with INH until 3-4m –> give TB test. If (-) TB test, continue INH for 9m total. allow breastfeeding after mother treated for >2w
consider BCG vaccine to infant if mom has multidrug resistant Tb
what is the most common source of VAP organisms?
oropharynx
what are examples of antigen presenting cells?
macrophages, dendritic cells and B lymphocytes
where do T cells mature and into what
originate in BM and mature and differentiate in thymus to CD4 or CD8 CD4: Mostly helper, receptors for MHC class II, secrete cytokines and signal to CD8 T cells and B cells CD8: Mostly cytotoxic killer, receptors for MHC class I, destruct virally infected cells
What are the 4 classes of CD4 T helper cells?
(4 types: Th1 (activate NK cells, macrophage and CD8 T cells, inflammatory), Th2 (influence B cells and eosinophil activation), T17 (secrete potent inflammatory iL-17) and T reg (downregulate immune response))
what is neonatal TB treatment
INH, rifampin, pyrazinamide, and an aminoglycoside
which organ dose congenital Tb present in first?
liver, seeds hematogenously from umb. vein
where does osteomyelitis present?
most commonly in long bones, lower > upper. Impacts the metaphysis which is most vascular component. Drains easier in neonates but also more likely to cause septic arthritis.
What are placental findings in CMV, syphillis and listeria?
CMV: inclusion cells, thrombosis, hemosiderin deposits
Syphillis: hypdropic/boggy/large/pale placenta, round cell infiltration/hypercellular placenta, inflamed and necrotizing villi
listeria: microabscesses
what measures reduce transmission of HIV to baby?
oral ppx during pregnancy IV treatment during labor 6w ppx for fetus avoid breastfeeding csec prior to ROM and labor if maternal viral load >1000
what is neonatal HIV status depending on testing?
presumed negative: x2- NAAT (>2w, >4w); x1- >8w; x1 - >6m
definitive negative: x2 - NAAT (>4w, >4m) ; x2 - NAAT > 6m
confirmed negative: definitive + no Ab at 18m
what are mechanisms of abx resistance for certain bugs
pseudomonas: decreased membrane permeability and efflux of abx out of cell
enterococci: changing adherance of drug to cell wall
s. aureus: encoding a protein for low affinity to b-lactam
ESBLs (Klebsiella and ?SPACE): enzyme inactivation to b lactam
how do aminoglycosides, antifungals, and b lactams work regarding MIC?
aminoglycosides (and vanc) work at peak –> Increase dose and make sure peak is good
b-lactams work at above MIC –> increase frequency and make sure you are above MIC for the most part
antifungals work with a combo of the above –> area under the curve
how does rotavirus do damage and why do neonates get less impacted by rotavirus?
- binds to enterocyte, activated by protease
- enterotoxigenic protein causes inflammation
- stimulates enteric nervous sytem
- usually benign course in neonates **
- may be reduced by breast feeding
- lactase on enterocyte bdinds to virus but is less abundance in neonate
why does rotavirus mostly spread in nicu?
difficult to eradicate with normal anti-infective measures
how does LCMV spread and present?
mouse vector, usually associated with substandard housing
- peripheral scarring in the eye
what is the best way to prevent MRSA infections?
surveillance cultures once you have a case of it
which maternal infection is most likely to cause congenital anomalies?
rubella, up to >80% in first trimester
what is the difference between bullous impetigo and SSSS?
both caused by staph by SSSS is due to systemic toxin vs BI which is local toxin. BI will have (+) cx from blisters which present with yellow clear fluid, rupture easily and leave small scale around rime
how do you diagnose EB and how does it present?
dx with biopsy, presents as blisters around areas of friction (back, extremities, etc.)
what is appropriate treatment for moderate to severely symptomatic CMV
IV gancyclovir and then oral valgancyclovir once able to tolerate po for 6m
which bug is assc with most mortality in LOS
pseudomonas
which bug does ppx erythromycin eye treatment treat
gonnorhea
most common EOS bugs
TERM: GBS, Ecoli
VLBS: Ecoli, CONS, GBS
