Fetal Pathology Flashcards
The fetal period begins following the completion of the ___ week of development
eighth
The perinatal period generally refers to the period around birth and variably regarded as:
3-5 months before birth, starting as early as 20 weeks gestation to as late as 28 weeks gestation. The perinatal period includes the first week following birth and thus overlaps with the neonatal period of the first four weeks of life.
T/F Approximately 50% of cases of early pregnancy loss (≤ 20 weeks gestation ) are due to genetic defects with the most common being monosomy X, triploidy and trisomy 16
T
most frequent aneuploid condition
trisomy 21
most common chromosomal aberration in early pregnancy loss
turners 45x
features of turners
small stature and gonadal dysgenesis resulting in adolescent presentation due to delayed menarche
prenatal detection of 45x
cystic hygroma +/- hydrops (also, horseshoe kidney, bicuspid aortic valve and coarctation of the aorta)
TORCH infections
toxoplasmosis, other (syphilis, parvo), rubella, cmv, herpes
rubella fetal triad
cataracts, hearing loss and heart murmur
highest risk to fetus from rubella occurs during weeks:
3-11 of gestation
CMV fetal triad
chorioretinitis, cerebral calcfications and microcephaly
TORCH infections are transmitted via ______ from the mother to the fetus
hematogenously (or transplacentally)
echogenic bowel
Congenital CMV –> area of gross bowel wall thinning and dilatation with thick intraluminal material
T/F Preterm infants have higher morbidity and mortality than full term infants.
T
risk factors for preterm birth
preterm premature rupture of placental membranes (PPROM), intrauterine infection, uterine, cervical, placental structural abnormalities, and mulptile gestation
Preterm delivery is classified as occurring at less than ___completed weeks of gestation
37
T/F Preterm infants that are SGA have higher mortality than age-matched infants of appropriate weight
T –> also, full-term infants may not suffer from complications of functional immaturity but can have increased morbidity due to growth restriction.
______ is the most common cause of early onset sepsis (within the first 7 days of life) and bacterial meningitis
Group B streptococcus
Complications of prematurity
hyaline membrane disease/chronic neonatal lung disease, necrotizing enterocolitis, intraventricular hemorrhage, sepsis, developmental delay
Most common cause of respiratory distress in
newborns
Hyaline Membrane Disease –> chest radiograph shows granular densities described as a “ground glass” appearance –> increased difficulty breathing beginning 30 minutes after birth progressing to cyanosis within hours
Infants born prematurely have decreased
surface area and a functional deficit of ____ in alveolar space.
surfactant, a lipoprotein secreted by type II pneumocytes (alveolar epithelial cells) that reduces surface tension within the alveoli. This structural and functional immaturity results in respiratory distress.
stages of alveolar development
pseudoglandular (6-16 weeks gestation), canalicular 16-28 weeks), saccular (28-36 weeks) and alveolar
T/F Administration of exogenous surfactant has decreased the incidence of hyaline membrane disease.
T
Pathophysiology of hyaline membrane disease/respiratory distress sydnrome
decreased alveolar surfactant –> increased alveolar surface tension –> hypoxemia and CO2 retention –> acidosis –> endothelial damage + vasoconstriction –> plasma leak into alveoli + necrosis –> increased diffusion gradient –> more hypoxemia and reduced surfactant production
Necrotizing enterocolitis
intestinal immaturity, immune immaturity, ischemia/hypoxia, genetic, feeding practices –> feeding intolerance, distension, bloody stool
T/F decreasing birthweight is associated with necrotizing enterocolitis
T
Long-term complications of necrotizing enterocolitis (NEC)
neurodevelopmental delay, growth delay, chronic GI disease (strictures, short gut syndrome, abdominal adhesions)
____ is a transient structure comprised of glial and neuronal cells with a dense venous network.
germinal matrix –> bleeding occurs in germinal matrix and spills into lateral ventricles –> hemorrhage typically occurs within hours of birth but can be delayed
One known obstetric risk factor for germinal matrix/intraventricular hemorrhage
vaginal breech delivery
T/F the older you are at birth, the lower the risk of germinal matrix hemorrhage
T –> germinal matrix disappears between 16-34 weeks so less of it is around at birth –> lower risk
T/F Benign pediatric tumors are more common than malignant ones.
T
