Question 1

A 27-year-old woman presented with a malodorous discharge in the vagina which started a week earlier. On examination, Whiff's test is positive and the gram stain shows the presence of clue cells. This infection is commonly treated with which of the following?

Accepted Answer

Metronidazole. ***Metronidazole***
  - This patient's symptoms (malodorous vaginal discharge, positive **Whiff test**, and presence of **clue cells** on Gram stain) are classic findings for **bacterial vaginosis (BV)**.
  - **Metronidazole** is the first-line and most effective antibiotic for treating bacterial vaginosis, as it targets the anaerobic bacteria overgrowing in the vagina.

*Azithromycin*
  - **Azithromycin** is primarily used to treat infections like **chlamydia**, gonorrhea, or some respiratory tract infections.
  - It is **not effective** against the anaerobic bacteria responsible for bacterial vaginosis.

*Nystatin pessary*
  - **Nystatin** is an **antifungal medication** specifically used to treat **vulvovaginal candidiasis (yeast infection)**.
  - The patient's presentation (malodorous discharge, positive Whiff test, clue cells) does not align with a yeast infection, making nystatin ineffective.

*Tetracycline*
  - **Tetracycline** is a broad-spectrum antibiotic, but it is **not the preferred treatment** for bacterial vaginosis.
  - Its use is often associated with a higher risk of side effects and is typically reserved for other bacterial infections like **chlamydia**, acne, or Rocky Mountain spotted fever. [Practice more OB/GYN questions on OnCourse]

Question 2

A female presents with postcoital bleeding. Which of the following is the most appropriate investigation?

Accepted Answer

Pap smear, HPV DNA testing. **Pap smear, HPV DNA testing**
- **Postcoital bleeding** is a classic symptom of **cervical cancer**, which can be identified by a **Pap smear** to detect abnormal cervical cells.
- **HPV DNA testing** is essential as persistent infection with high-risk human papillomavirus (HPV) genotypes is the primary cause of cervical cancer.

*Pap smear, HCV DNA, electrophoresis*
- While a **Pap smear** is appropriate for cervical cytology, **HCV DNA testing** is for Hepatitis C virus infection and is not routinely indicated for postcoital bleeding.
- **Electrophoresis** is used to analyze proteins (e.g., hemoglobinopathies) and has no direct role in evaluating postcoital bleeding or cervical pathology.

*Liquid-based cytology, cervical biopsy*
- **Liquid-based cytology** is a method of preparing a Pap smear, but it's not a standalone investigation.
- A **cervical biopsy** is a more invasive procedure done *after* initial screening (like Pap smear with HPV testing) suggests abnormalities, not as a primary first-line investigation for postcoital bleeding unless there are visible lesions.

*Cervical biopsy, HBV DNA*
- A **cervical biopsy** is typically performed following an abnormal **Pap smear** or colposcopy findings, not as the initial diagnostic step for postcoital bleeding.
- **HBV DNA testing** is for Hepatitis B virus infection and is irrelevant to the workup of postcoital bleeding. [Practice more OB/GYN questions on OnCourse]

Question 3

Which of the following is a tumor marker associated with ovarian solid-cystic masses?

Accepted Answer

AFP. ***AFP (Alpha-fetoprotein)***
  - **AFP** is a reliable tumor marker for differentiating **germ cell tumors**, especially **yolk sac tumors**, which often present as an ovarian solid-cystic mass.
  - Elevated **AFP** levels help in diagnosis, monitoring treatment response, and detecting recurrence of these specific ovarian malignancies.

*CEA (Carcinoembryonic antigen)*
  - **CEA** is primarily associated with **gastrointestinal cancers**, such as colorectal cancer, and is less specific for ovarian masses.
  - While it can be elevated in some mucinous ovarian carcinomas, it's not the most specific marker for a general solid-cystic ovarian mass.

*HCG (Human chorionic gonadotropin)*
  - **HCG** is a key marker for **gestational trophoblastic disease** and some **germ cell tumors**, such as choriocarcinoma.
  - It is not typically elevated in most common solid-cystic ovarian masses, especially those of epithelial origin.

*HER2/neu (Human Epidermal growth factor Receptor 2)*
  - **HER2/neu** is primarily associated with **breast cancer** and some gastric cancers, playing a role in targeted therapy.
  - It is not a standard tumor marker for the general evaluation or diagnosis of ovarian solid-cystic masses. [Practice more OB/GYN questions on OnCourse]

Question 4

A 45-year-old woman presents with a history of cervical erosion and spotting for the past 2 months. What is the next best step?

Accepted Answer

LBC + HPV. ***LBC + HPV***
  - Cervical erosion and spotting are concerning for **cervical intraepithelial neoplasia (CIN)** or **cervical cancer**, making **Liquid-Based Cytology (LBC)** the appropriate screening method.
  - **Human Papillomavirus (HPV) testing** is crucial as persistent high-risk HPV infection is the primary cause of cervical cancer and helps in risk stratification and management.

*Pap smear + HSV*
  - A **routine Pap smear** (conventional cytology) is less sensitive than LBC for detecting abnormal cervical cells and is generally being phased out by LBC.
  - **Herpes Simplex Virus (HSV)** causes genital herpes and is not directly associated with cervical cancer, thus testing for it in this context is not the most appropriate immediate next step.

*Pap smear + HBV*
  - As mentioned, a **routine Pap smear** is not the preferred method for cervical cancer screening compared to LBC.
  - **Hepatitis B Virus (HBV)** causes liver disease and is entirely unrelated to cervical pathology; therefore, testing for it would be irrelevant to the patient's symptoms.

*LBC + HSV*
  - While **LBC** is the correct advanced cytology method, adding **HSV testing** is not indicated as HSV does not cause cervical cancer or intraepithelial lesions that present with cervical erosion and spotting.
  - Focus should be on identifying potential malignancy or pre-malignant changes with HPV co-testing, not sexually transmitted infections unrelated to cancer risk. [Practice more OB/GYN questions on OnCourse]

Question 5

A 25-year-old pregnant woman, at 18 weeks of gestation, undergoes a routine ultrasound scan. The ultrasound images provided show below. Based on the imaging findings, what is the most likely diagnosis?

Accepted Answer

Spina bifida. ***Spina bifida***
- The ultrasound image shows a **defect in the posterior elements of the fetal spine**, with characteristic splaying or widening of the vertebral arches.
- This is a **neural tube defect** resulting from incomplete closure of the spinal column during embryonic development.
- Associated findings on prenatal ultrasound may include the **"lemon sign"** (scalloping of frontal bones) and **"banana sign"** (abnormal cerebellar shape).
- Spina bifida is typically detected on **second-trimester anatomy scan** (18-20 weeks).

*Anencephaly*
- This condition involves the **absence of a major portion of the brain, skull, and scalp** due to failure of anterior neural tube closure.
- On ultrasound, anencephaly presents with **absent calvarium above the orbits** and absent cerebral hemispheres, which is distinctly different from a spinal defect.
- This would be a **cranial abnormality**, not a spinal column defect.

*Encephalocele*
- An **encephalocele** is a protrusion of brain tissue and meninges through a defect in the skull, most commonly at the **occipital region**.
- On ultrasound, this appears as a **cranial mass** extending beyond the skull contour, not a spinal defect.

*Holoprosencephaly*
- This condition results from **failure of forebrain (prosencephalon) to divide properly** into two hemispheres.
- Ultrasound findings include **single ventricle**, fused thalami, and absent midline structures, often with associated **facial anomalies**.
- The imaging would show **brain abnormalities**, not spinal column defects.

*Iniencephaly*
- This is a rare **neural tube defect** characterized by extreme retroflexion of the head with severe spinal defects in the cervical and thoracic regions.
- On ultrasound, iniencephaly shows the fetal head in extreme **hyperextension** with the face looking upward, creating a characteristic "stargazing" appearance.
- This differs from the typical spinal defect pattern seen in spina bifida. [Practice more OB/GYN questions on OnCourse]

OB/GYN Questions

Topics

Screening tests

High-risk pregnancies

Prenatal Care

Stages of labor

Postpartum hemorrhage

Labor Complications