2011 plus Flashcards

Question

. Micromelia, slightly bowed with normal ossification?* a. thanatotrophic b. camplomelia c. osteogenous imperfecta d. heterozygous achondroplasia

Answer 1

campomelia? = mild micromelia + bowing, normal ossification thanatophoric: normal mineralization, no fractures, severe micromelia (but no comment about bowing)

Answer 2

Echogenic bowel!

Answer 3

Echogenic bowel!

Answer 4

B? not sure...

Answer 5

Answer: A Normal pregnancy is associated with hemodynamic changes that may be poorly tolerated in women with mitral stenosis (MS). The increase in cardiac output is due to increases in both heart rate, which shortens the diastolic filling time, and stroke volume. The resting transmitral gradient increases by the square of the cardiac output. As a result, a 1.5-fold (ie, 50%) increase in cardiac output causes a 2.3-fold increase in the resting transmitral gradient. In general, the patient’s symptomatic status during pregnancy will increase by about one NYHA class. Thus, a woman who is asymptomatic before pregnancy may develop mild symptoms. For women with severe mitral stenosis or symptoms of heart failure at the time of labor, invasive hemodynamic monitoring with a right heart catheter is appropriate. Fluid management to achieve a goal pulmonary capillary wedge pressure of ~14 mmHg is generally recommended, although this may need to be adjusted on an individual basis. Invasive hemodynamic monitoring should be continued in the immediate postpartum period because of large intravascular volume shifts. Creasy p. 811. Inflow to the LV is impeded by the narrowed valve and can only be accomplished by an increased level of pressure in the LA. Tachycardia worsens MS status. (Gabbe pg 1012): impedes the flow from the left atrium to ventricle, symptoms usually occurs when the valvular area is <2.5cm with exercise and <1.5cm at rest. Cardiac output is limited by passive flow through the valve during diastole; increased venous return results in pulmonary congestion. Tachycardia can also decrease left ventricular filling and increases pulmonary congestion. Beta blockade increases flow through the valve and decreases pulmonary congestion. During labor, uterine contractions increase venous return and pulmonary congestion. Aggressive anticipatory diuresis will reduce pulmonary congestion. Williams page 1024: Abrupt increases in preload may lead to pulmonary edema. Care must be taken to avoid fluid overload.

Answer 6

Answer: e Prenatal diagnosis should be offered to women suspected of having a primary or nonprimary CMV infection, since it is often difficult to distinguish the two types of infection in a timely manner. The rationale for offering prenatal diagnosis is the potential for severe sequelae in offspring, especially with primary maternal infection. Amniocentesis to perform PCR for CMV DNA in amniotic fluid is the preferred diagnostic approach for identifying an infected fetus; viral culture is less desirable because of several limitations. Reported sensitivity of PCR ranges from 70-100%. Timing of amniocentesis appears to be a critical factor influencing sensitivity: sensitivity appears to be higher after 21 weeks of gestation and by allowing a six-week lag time between maternal infection and amniocentesis. The six-week lag time reflects the time it takes for placental infection and replication, transmission to the fetus, viral replication in the fetal kidney, and excretion into amniotic fluid. In one series, the sensitivity for cases first sampled before and after 21 weeks of gestation was 30 and 71%, respectively. If amniocentesis is performed earlier in gestation or soon after diagnosis of maternal infection, it is reliable evidence of fetal infection if positive, but should be repeated later in gestation if negative. Rarely, false positive results occur from contamination of the amniotic fluid sample by maternal fluids. Need a 6 week lag between infection and diagnosis in the fetus, so CVS is not possible if exposure occurred at 10 weeks. Most sensitive after 21 weeks, so (e) is correct.

Answer 7

Answer: B Although the placenta does not synthesize glucocorticoids de novo, it regulates exposure of the fetus to glucocorticoids by the 11ß-hydroxy-steroid dehydrogenase enzymes, which catalyze reduction (11ß-HSD1) or oxidation (11ß-HSD2) of glucocorticoids. 11ß-HSD2 is located throughout the syncytiotrophoblast layer where its expression increases with gestational age, and it serves to metabolize cortisol to inactive cortisone, thus protecting the fetus against excessive exposure to maternal cortisol. Additionally, a substantial increase in 11ß-HSD2 is observed around 10 to 12 weeks of gestation when blood flow to the intervillous space is established. An increase in the ratio of 11ß-HSD2 to 11ß-HSD1 in placental membranes near term is associated with a switch in placental glucocorticoid metabolism, which may be responsible for the maturation of the fetal hypothalamic-pituitary-adrenal axis.

Answer 8

Answer: D Detection of leptin in fat biopsies obtained between weeks 20 and 38 of gestation provides evidence that adipose tissue of human fetuses produces leptin, at a developmental stage when it can be delivered into the fetal circulation. (Journal of Clinical Endocrinology & Metabolism, June 2001) Williams page 895. Insulin and Insulin like growth factor IGFI and II have a role in regulation and fetal growth. Insulin is secreted by pancreatic B cells during the second half of gestationand is believed to stimulate somatic growth and adiposity.Leptin increases in 1st and 2nd trimester. It is synthesized by adipose tissue and levels correlates with birth weight. Glucose i.e. excessive glycemia leads to macrosomia and dimisnished glucose levelsare associated with growth restrictions.

Answer 9

? Answer: A Estrogens are secreted by the corpus luteum and the adrenal cortex, as well as the placenta. hCG stimulates the synthesis of estrogen in the placenta, where the syncytiotrophoblast produces it in large quantities. However, the placenta alone is not capable of estrogen production de novo as it cannot hydroxylate C21 steroids at the 17 position. The maternal, and primarily the fetal, bloodstreams that perfuse the placenta provide dehydroepiandrosterone sulfate (DHEAS), the substrate for estrone and estradiol, and 16-hydroxy-DHEAS, the substrate for estriol. Large amounts of DHEAs are secreted by the fetal adrenal glands and converted to estrogens in the placenta. Hydrolysis by placental sulfatase yields DHEA and 16-hydroxy-DHEA, which are then acted on by 3-HSD and aromatase to yield estrogens. Aromatase is oxygen sensitive, which may account for the low concentration of estrogens in women with placental insufficiency. Placental production of estrogens increases in a linear fashion to term. (Up to Date) DHEA-s because the fetal adrenals are making it? Hard question

Answer 10

Answer: A 2-Chloroprocaine

Answer 11

not sure Answer: a) Erythro – limited transfer (~3% transfer) b) gent – incomplete transfer (~30% of maternal serum levels) c) cephalosporin – variable, complete to incomplete transfer d) amp? – complete transfer e) sulfamethoxazole? – readily crosses the placenta 3 types of placental transfers were identified. A few antibiotics cross the placenta rapidly and equilibrate in the maternal and cord plasma; this type of transfer is termed "complete" and include the antibiotics ampicillin, methicillin, cefmenoxime and cefotiam. Antibiotics which show incomplete transfer to the placenta where concentrations are lower in the cord than maternal plasma are said to have "incomplete" transfer and these include azlocillin, dicloxacillin, piperacillin, sulbenicillin, cefoxitin, amikacin, gentamicin, kanamycin, streptomycin, fosfomycin, thiamphenicol, griseofulvin, vancomycin and colistimethate. Ceftizoxime is the only antibiotic so far known whose concentrations are higher in the cord than maternal plasma. This type of transfer is called "exceeding" transfer. It would appear that trimethoprim is slowly transported across the placenta and in low concentrations whereas sulfamethoxazole readily crosses the placenta. The limited transplacental transfer of erythromycin, roxithromycin and azithromycin suggests compromised efficacy in the treatment of fetal infections. On the other hand, the placenta seems to produce an effective barrier reducing the fetal exposure when these three macrolides are used to treat maternal infections.

Answer 12

Answer: B PRIDE study— Prolongation of the PR interval was uncommon and did not precede more advanced block. There was a trend toward more congenital heart block in fetuses of women with previously affected offspring than those without previously affected offspring. Advanced block and cardiomyopathy can occur within 1 week of a normal echocardiogram without initial first-degree block. Echodensities and moderate/severe tricuspid regurgitation merit attention as early signs of injury. Among women with such antibodies, complete heart block occurs in approximately 2% of pregnancies. Once such a woman has given birth to an infant with congenital heart block, the recurrence rate of congenital heart block in subsequent pregnancies is about 15%; another 6% have an isolated rash consistent with neonatal lupus. Anti-Ro/SSA and/or anti-La/SSB antibodies bind to fetal cardiac tissue, leading to autoimmune injury of the AV node and its surrounding tissue. Both Ro/SSA and La/SSB antigens are abundant in fetal heart tissue between 18-24 weeks. Apoptosis induces translocation of Ro/SSA and La/SSB to the surface of fetal cardiomyocytes; anti-Ro and anti-La antibodies then bind to the surface of the fetal cardiocytes and induce the release of tumor necrosis factor by macrophages, which then results in fibrosis. In addition to inducing tissue damage, anti-Ro/SSA and/or anti-La/SSB antibodies inhibit calcium channel activation or the cardiac L- and T- type calcium channels themselves; L-type channels are crucial to action potential propagation and conduction in the AV node. The SA node also may be involved. Sinus bradycardia has been described in 3.8% of fetuses but is usually not permanent. Patients with the neonatal lupus syndrome may have a variety of other cardiac abnormalities, including ventricular septal defect and endocardial fibroelastosis. Congenital heart block may present with fetal bradycardia between 18-28 weeks of gestation. Almost all of these cases are due to neonatal lupus, as demonstrated by the presence of anti-Ro/SSA and/or anti-La/SSB antibodies in the maternal serum. In utero detection is made by echocardiography, which can estimate the fetal PR interval. Associated complications in utero can include hydrops fetalis, endocardial fibroelastosis, pericardial effusion, and spontaneous intrauterine fetal death. Second degree block detected in utero can progress to complete heart block. (Up to date)