Obstetrics COPY Flashcards
A 28-year-old woman presents at 36 weeks’ gestation with rupture of membranes. On examination she is found to have 7 cm cervical dilatation. She received all of her prenatal care, and her only complication was a course of antibiotics for asymptomatic bacteriuria. GBS screening was negative. Her first baby was hospitalized for 10 days after delivery for GBS pneumonia and sepsis. What is the most appropriate management?
a. Administer intrapartum IV penicillin
b. Administer intramuscular azithromycin
c. Rescreen for group B streptococci
d. Schedule cesarean section
e. No intervention is needed
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12602-12613). Kaplan Publishing. Kindle Edition.
A. Intrapartum IV penicillin is indicated because the patient’s previous birth was complicated with neonatal GBS sepsis.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12602-12613). Kaplan Publishing. Kindle Edition.
True or False:
- Thirty percent of women have asymptomatic vaginal colonization with GBS
- Vertical transmission results in pneumonia and sepsis in the neonate within hours to days of birth
- There is a 50 percent mortality rate with neonatal infection
- GBS-related meningitis occurs after the first week and is a hospital-acquired infection that is related to vertical transmission
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12613-12632). Kaplan Publishing. Kindle Edition.
- True
- True
- True
- False. The infection is unrelated to vertical transmission
List the Rx of GBS
- Intrapartum IV penicillin G
- Penicillin allergy: IV cefazolin, clindamycin, or erythromycin
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12613-12632). Kaplan Publishing. Kindle Edition.
Indications for Rx of GBS
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12613-12632). Kaplan Publishing. Kindle Edition.
- GBS (+) urine, cervical, or vaginal culture at any time during pregnancy
- Presence of high-risk factors:
- Preterm delivery
- Membrane rupture > 18 hours
- Maternal fever
- Previous baby with GBS sepsis
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12613-12632). Kaplan Publishing. Kindle Edition.
Exceptions to antibiotic use in GBS
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12634-12654). Kaplan Publishing. Kindle Edition.
- Planned c-section without rupture of membranes (even if culture is [+])
- Culture (+) on a previous pregnancy, but culture (–) in the current pregnancy
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12634-12654). Kaplan Publishing. Kindle Edition.
Interpret the following results:
- IgG antibodies to GBS in the mother
- IgM antibodies to GBS in the mother
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12613-12632). Kaplan Publishing. Kindle Edition.
- Past exposure and are protective
- Suggests recent exposure and risk of exposure to the fetus.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12613-12632). Kaplan Publishing. Kindle Edition.
Toxoplasmosis in the infant:
- Causative organism
- Risk factors (RF)
- Prevention
- Rx
- Toxoplasma gondii
- RF:
- Patient handling cat feces or litter boxes
- Drinking raw goat milk
- Eating raw meat.
- Prevention: Avoid risk factors
- Pyrimethamine and sulfadiazine
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12634-12654). Kaplan Publishing. Kindle Edition.
Diagnosis:
- Chorioretinitis
- Intracranial calcifications
- Hydrocephalus
Congenital toxoplasmosis
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12634-12654). Kaplan Publishing. Kindle Edition.
A 29-year-old woman (G2 P1) is at 34 weeks’ gestation. She complains of uterine contractions every 5 minutes. Her previous records are not available. During the last few days, she has developed diffuse pruritic vesicles on her neck, which appear to be also developing on her chest and breasts. She has a fever and complains of malaise. Which of the following is the next step in management?
a. Oral acyclovir
b. RhoGAM
c. Varicella zoster antibody assay
d. Varicella vaccine
e. Varicella zoster immunoglobulin
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12661-12673). Kaplan Publishing. Kindle Edition.
C. Varicella antibodies are seen in 90 percent of pregnant women due to prior infection. Varicella antibodies are protective, and no therapy is necessary
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12661-12673). Kaplan Publishing. Kindle Edition.
- Diagnosis:
- Zigzag” skin lesions
- Limb hypoplasia
- Microcephaly
- Microphthalmia
- Chorioretinitis
- Cataracts.
- Prevention of above
- Rx of above
- Neonatal varicella infection. Transplacental infection results from primary varicella infection in the mother (25– 40 percent infection rate). The greatest risk to the fetus is if a rash appears in the mother between 5 days antepartum and 2 days postpartum.
- Prevention
- Vaccination: Live-attenuated varicella virus (Varivax III) to nonpregnant women
- Postexposure prophylaxis: VariZIG (antivaricella antibodies) or varicella zoster immunoglobulin within 96 hours of exposure. VariZIG/ VZIG does not prevent infection but only attenuates the clinical effects of the virus.
- Treatment
- Maternal varicella: VariZIG to mother and neonate
- Congenital varicella: VariZIG and IV acyclovir to the neonate
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12674-12691). Kaplan Publishing. Kindle Edition.
Diagnosis:
- Congenital deafness (most common sequelae)
- Ccongenital heart disease (e.g., patent ductus arteriosus, or PDA)
- Cataracts
- Mental retardation
- Hhepatosplenomegaly
- Tthrombocytopenia
- “Blueberry muffin” rash
Prevention?
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12674-12691). Kaplan Publishing. Kindle Edition.
Diagnosis: Congenital rubella
Prevetion:
- Perform first-trimester screening and have mother avoid infected individuals
- Immunize seronegative women after delivery
- No postexposure prophylaxis is available
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12692-12713). Kaplan Publishing. Kindle Edition.
A 24-year-old child-care worker is 29 weeks pregnant and is currently working. One of the children was diagnosed with rubella last week. Rubella antigen testing is performed and her IgG titer is negative. What is the risk of neonatal transmission in this patient? What is the next step in management?
a. Give anti-rubella antibodies
b. Give betamethasone
c. Give rubella vaccine now
d. Give rubella vaccine after delivery
e. Ultrasound of the fetus
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12692-12713). Kaplan Publishing. Kindle Edition.
D. There is no postexposure prophylaxis available, and immunization during pregnancy is contraindicated (live vaccine). The only correct management is to await normal delivery and give vaccination to the mother after delivery
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12692-12713). Kaplan Publishing. Kindle Edition.
Diagnosis:
- Most common congenital viral syndrome in the United States
- Most common cause of sensorineural deafness in children
- Spread by infected body fluid secretions
- The greatest risk for vertical transmission occurs with primary infection (infection rate is 50 percent)
- Most mothers develop asymptomatic infections or describe mild, mononucleosis-like symptoms.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12692-12713). Kaplan Publishing. Kindle Edition.
Cytomegalovirus (CMV)/Congenital CMV
About 10% of infants with congenital CMV infection are symptomatic at birth
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12692-12713). Kaplan Publishing. Kindle Edition.
Diagnosis:
- Intrauterine growth restriction (IUGR)
- Prematurity
- Microcephaly
- Jjaundice
- Petechiae
- Hepatosplenomegaly
- Periventricular calcifications
- Chorioretinitis
- Pneumonitis
Congenital CMV
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12713-12729). Kaplan Publishing. Kindle Edition.
Interpretation of results:
- Maternal IgG (+) / IgM (–)
- Maternal IgG (+) / IgM (+)
- Maternal IgG (–) / IgM (+) indicates recent infection.
- Indicates past exposure and no risk for primary infection
- Indicates recent infection
- Indicates recent infection
Perform a viral culture from urine or other body fluids in first 2 weeks of life and CMV DNA-PCR
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12713-12729). Kaplan Publishing. Kindle Edition.
- Prevention of CMV
- Rx of CMV
- Prevention:
- Follow universal precautions with all body fluids.
- Avoid transfusion with CMV-positive blood
- Treatment:
- Antiviral therapy with ganciclovir. This prevents viral shedding and prevents hearing loss but does not cure the infection
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12713-12729). Kaplan Publishing. Kindle Edition.
A 21-year-old multipara is admitted to the birthing unit at 39 weeks gestation in active labor at 6 cm dilation. Membranes are intact. She has a history of genital herpes preceding the pregnancy. Her last outbreak was 8 weeks ago. She now complains of pain and pruritus. On examination, she had localized, painful, ulcerative lesions on her right vaginal wall. Which of the following is the next step in management?
a. Administer IV acyclovir
b. Administer terbutaline
c. Obtain culture of ulcer
d. Proceed with vaginal delivery
e. Schedule cesarean section
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12729-12748). Kaplan Publishing. Kindle Edition.
E. Active genital herpes is an indication for cesarean section. The only other infection-related indication for cesarean section is HIV sero-positive status of the mother
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12729-12748). Kaplan Publishing. Kindle Edition.
True or False:
- The most common cause of transmission is contact with maternal genital lesions during an active HSV episode.
- Transplacental infection can also occur with primary infections during pregnancy (50 percent risk).
- Greatest risk is primary infection in the third trimester.
- Neonatal infection acquired during delivery has 50 percent mortality rate.
- Surviving infants develop meningoencephalitis, mental retardation, pneumonia, hepatosplenomegaly, jaundice, and petechiae.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12729-12748). Kaplan Publishing. Kindle Edition.
- True
- True
- True
- True
- True
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12729-12748). Kaplan Publishing. Kindle Edition.
Diagnostic test for HSV
Rx of HSV
Diagnostic Testing (+) HSV culture from vesicle fluid or ulcer or HSV PCR of maternal blood (not screened routinely)
Rx: Acyclovir
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12729-12748). Kaplan Publishing. Kindle Edition.
Prevention of HSV
- Perform c-section in women with lesions suspicious for active genital HSV at the time of labor
- Do not use fetal scalp electrodes for monitoring (increased risk of HSV transmission)
- Manage expectantly for premature rupture of membranes (PROM) or prolonged rupture of membranes (ROM) (i.e., > 8–12 hours)
- Advise standard precautions (avoid intercourse if partner has active lesions, avoid oral sex in presence of oral lesions, avoid kissing neonate in presence of oral lesions)
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12749-12766). Kaplan Publishing. Kindle Edition.
A 24-year-old HIV positive female (G2 P1) presents in her 16th week of pregnancy. Her previous child was diagnosed HIV positive after vaginal delivery. What is the most effective method of decreasing the risk of vertical transmission?
a. Avoidance of artificial rupture of membranes
b. Avoidance of breastfeeding
c. Antiretroviral triple therapy
d. Cesarean section
e. Zidovudine monotherapy
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12749-12766). Kaplan Publishing. Kindle Edition.
C. All of the strategies are recommended, however. Zidovudine (ZDV) monotherapy is not as effective as triple therapy in decreasing the risk of HIV transmission to the fetus (25 percent to 8 percent). Triple antiretroviral therapy is indicated for more effective management of HIV in the mother to drive the viral load to < 1,000. ZDV monotherapy alone is never indicated. Cesarean section (before rupture of membranes), avoidance of breastfeeding or intrapartum invasive procedures (artificial ROM, fetal scalp electrodes) also decreases transmission rate. Combination of all of the above strategies listed above reduces the transmission rate to 1 percent.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12749-12766). Kaplan Publishing. Kindle Edition.
HIV
- True or False: Major route of vertical transmission is contact with infected genital secretions at the time of vaginal delivery
- What is the vertical transmission rate without Rx
- True or False: . Elective cesarean is of most benefit in women with low CD4 counts and high RNA viral loads (> 1,000)
- True or False: All neonates of HIV-positive women will have positive HIV tests from transplacental passive IgG passage
- True or False: Zidovudine monotherapy is no longer indicated for anyone
- Continue antiretrovirals in pregnancy for HIV (+) patients with low CD4 counts and/ or high viral load.
- True
- 25– 30 percent
- True
- True
- True
- True
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12766-12786). Kaplan Publishing. Kindle Edition.
Outline Prevention and Rx of HIV in pregnancy
- Triple-drug therapy (which must include ZDV):
- Starting at 14 weeks for mothers who have high CD4 counts and do not need medication for their own health and continuing throughout pregnancy
- Intravenous intrapartum ZDV
- Combination ZDV-based ART for 6 weeks after delivery
- Give the infant prophylaxis against pneumocystis pneumonia (trimethoprim-sulfamethoxazole) and continue for 6 weeks after AZT therapy has been completed
- Schedule C-section at 38 weeks unless < 1,000 viral copies/mL
- Advise the mother not to breastfeed
- Avoid invasive procedures (e.g., artificial rupture of membranes, fetal scalp electrodes).
HIV-infected pregnant women should receive ART therapy regardless of HIV RNA level
Do a c-section of the mother’s viral load is > 1,000 at the time of delivery.
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12766-12786). Kaplan Publishing. Kindle Edition.
- True or False: Prior syphilis infection confers immunity
- True or False: Transplacental infection results from primary and secondary infection (60 percent risk of transmission)
- True or False: The lowest risk of transmission is with latent or tertiary infection.
- False
- True
- True
Fischer, Conrad (2012-09-22). Master the Boards: USMLE Step 3 (Kaplan Medical Usmle Master the Boards Step 3) (Kindle Locations 12789-12804). Kaplan Publishing. Kindle Edition.