Screening/lab tests Flashcards
When can pap smears be stopped?
Patients with a uterus can discontinue cervical cancer screening between the ages of 65-70 if they have had 3 consecutive negative smears or two negative consecutive cotesting in the last 10 years and no history of high-grade cervical intraepithelial neoplasia or cancer.
What is the next step for a return pap result of atypical squamous cells of undetermined significance (ASCUS)?
HPV typing; if a high-risk HPV type is detected, then the patient needs a colposcopy with biopsies.
What is the most sensitive screening test during pregnancy for trisomy 21?
Cell-free DNA screening
What is the risk of fetal loss with chorionic villus sampling?
1%
What is the best non-invasive test to detect fetal anemia?
Doppler ultrasonography of the middle cerebral artery peak systolic velocity. Useful if red cell alloimmunization is suspected (Rh- mother with Rh+ baby)
What is the usefulness of a fetal fibronectin test when assessing preterm labor?
Fibronectin is thought to act as an adhesive between the fetal membranes and underlying decidua. Its presence in the cervical mucus between 22 and 34 wks is thought to indicate a disruption or injury to the maternal-fetal interface. It has a 99% negative predictive value in symptomatic women and 96.7% in asymptomatic women in predicting whether a woman will deliver in the next 14 days (e.g. 99% of women will not deliver in 14 days if they have a negative test). The positive predictive value is only 16.7%.
What is the discriminatory zone (beta-hCG level at which an IUP should be seen)?
1500-2000
Above what crown-rump length without cardiac activity is a fetus considered non-viable?
7 mm
When is chorionic villus sampling (CVS) vs amniocentesis performed?
CVS: 10-12 wks
Amniocentesis: after 15 wks
What are the risks of CVS over amniocentesis?
Early CVS (<10 wks) is associated with an increase in limb abnormalities. There is also a higher failure rate to obtain an adequate sample
What is the work up for suspected antiphospholipid antibody syndrome?
Anticardiolipin and beta-2 glycoprotein antibody status (positive), PTT (prolonged), and Russel viper venom time (prolonged)
What are the management steps for a pap test that comes back ASCUS?
Perform HPV DNA testing and/or cytology at 12 months. If the HPV test is negative, repeat in 3 years. If it is positive or cyctology comes back ASCUS or higher, than perform a colposcopy.
What is the Kleihauer-Betke test for?
A blood test used to measure the amount of fetal hemoglobin transferred from a fetus to a mother’s bloodstream.
What test should be used in a woman <30 with a palpable breast mass without increased risk for breast cancer?
A breast ultrasound. You may also choose to repeat the breast exam in 6 weeks. Mammograms are usually not indicated for women under 30 with average risk
When should breast cyst fluid be sent for cytology?
If it is bloody or blood-tinged or if there is an intracystic solid nodule. If the fluid is clear, yellowish, greenish, white or black (“motor oil”-appearing) it does not need to be sent if there are no solid parts to the cyst.
