HIV in pregnancy and vertical transmission US Medical PG Practice Questions and MCQs
Practice US Medical PG questions for HIV in pregnancy and vertical transmission. These multiple choice questions (MCQs) cover important concepts and help you prepare for your exams.
HIV in pregnancy and vertical transmission US Medical PG Question 1: A 2300-g (5-lb 1-oz) male newborn is delivered to a 29-year-old primigravid woman. The mother has HIV and received triple antiretroviral therapy during pregnancy. Her HIV viral load was 678 copies/mL 1 week prior to delivery. Labor was uncomplicated. Apgar scores are 7 and 8 at 1 and 5 minutes respectively. Physical examination of the newborn shows no abnormalities. Which of the following is the most appropriate next step in management of this infant?
- A. Administer lamivudine and nevirapine
- B. Administer zidovudine, lamivudine and nevirapine (Correct Answer)
- C. Administer nevirapine
- D. Administer zidovudine
- E. HIV antibody testing
HIV in pregnancy and vertical transmission Explanation: ***Administer zidovudine, lamivudine and nevirapine***
- The mother has a **viral load of 678 copies/mL**, which falls into the **intermediate-risk category** (50-999 copies/mL) for HIV transmission.
- Current guidelines recommend **combination antiretroviral prophylaxis** (zidovudine + lamivudine + nevirapine) for infants born to mothers with viral loads in this range, typically given for 2 weeks followed by zidovudine alone to complete 4-6 weeks.
- This enhanced regimen provides better protection than monotherapy when maternal viral suppression is suboptimal.
*Administer zidovudine*
- Zidovudine monotherapy is reserved for **low-risk infants** whose mothers have viral loads **<50 copies/mL** at delivery with documented adherence to ART during pregnancy.
- With a maternal viral load of 678 copies/mL, monotherapy alone is **insufficient** and would not meet current standard of care for HIV prophylaxis.
*Administer lamivudine and nevirapine*
- This regimen omits **zidovudine**, which remains the **backbone of neonatal HIV prophylaxis** and should always be included.
- Using only lamivudine and nevirapine without zidovudine is not consistent with established guidelines.
*Administer nevirapine*
- Nevirapine monotherapy is **not adequate** for HIV prophylaxis in developed countries with access to combination therapy.
- While nevirapine may be used as a single dose in resource-limited settings, it should be part of a multi-drug regimen when other agents are available.
*HIV antibody testing*
- HIV antibody testing in newborns will detect **maternal antibodies** that crossed the placenta and cannot determine the infant's true infection status at birth.
- While HIV diagnostic testing using **PCR or viral load assays** will be performed at 14-21 days, 1-2 months, and 4-6 months of age, **antiretroviral prophylaxis must be initiated immediately** after birth to prevent transmission.
HIV in pregnancy and vertical transmission US Medical PG Question 2: A 27-year-old pregnant woman presents to an obstetrician at 35 weeks gestation reporting that she noted the presence of a mucus plug in her vaginal discharge this morning. The obstetrician performs an examination and confirms that she is in labor. She was diagnosed with HIV infection 1 year ago. Her current antiretroviral therapy includes abacavir, lamivudine, and nevirapine. Her last HIV RNA level was 2,000 copies/mL 3 weeks ago. Which of the following anti-retroviral drugs should be administered intravenously to the woman during labor?
- A. Enfuvirtide
- B. Nevirapine
- C. Abacavir
- D. Rilpivirine
- E. Zidovudine (Correct Answer)
HIV in pregnancy and vertical transmission Explanation: ***Zidovudine***
- Intravenous **zidovudine** is recommended during labor for HIV-positive pregnant women, especially when the viral load is **>1000 copies/mL**, to reduce the risk of **mother-to-child transmission (MTCT)**.
- This intervention significantly lowers the viral load in the maternal blood and reduces fetal exposure to the virus during delivery.
*Enfuvirtide*
- **Enfuvirtide** is a **fusion inhibitor** administered subcutaneously, not intravenously, and is reserved for treatment-experienced patients with multi-drug resistant HIV.
- It is not a standard recommendation for intrapartum prophylaxis against MTCT.
*Nevirapine*
- **Nevirapine** is an **NNRTI** that is typically given orally, and while it has been used for MTCT prophylaxis, intravenous administration is not standard for intrapartum use.
- The woman is already on oral nevirapine as part of her ART regimen.
*Abacavir*
- **Abacavir** is an **NRTI** given orally and is part of the patient's current ART regimen.
- It is not administered intravenously for intrapartum MTCT prophylaxis.
*Rilpivirine*
- **Rilpivirine** is an **NNRTI** that is taken orally and is not indicated for intravenous administration during labor to prevent MTCT.
- Its use is limited by potential drug interactions and efficacy in patients with high viral loads.
HIV in pregnancy and vertical transmission US Medical PG Question 3: A 28-year-old G1P0 woman at 16 weeks estimated gestational age presents for prenatal care. Routine prenatal screening tests are performed and reveal a positive HIV antibody test. The patient is extremely concerned about the possible transmission of HIV to her baby and wants to have the baby tested as soon as possible after delivery. Which of the following would be the most appropriate diagnostic test to address this patient’s concern?
- A. CD4+ T cell count
- B. Viral culture
- C. Polymerase chain reaction (PCR) for HIV RNA (Correct Answer)
- D. Antigen assay for p24
- E. EIA for HIV antibody
HIV in pregnancy and vertical transmission Explanation: ***Polymerase chain reaction (PCR) for HIV RNA***
- **PCR for HIV RNA** directly detects the viral genetic material, providing a definitive diagnosis of HIV infection in an infant.
- Unlike antibody tests, PCR can distinguish between passively acquired maternal antibodies and actual infant infection, making it suitable for newborns.
*CD4+ T cell count*
- **CD4+ T cell count** is used to monitor the progression of HIV infection and immunosuppression, not for initial diagnosis, especially in neonates.
- While it's an important marker for HIV disease, it does not confirm the presence of the virus itself in a newborn.
*Viral culture*
- **Viral culture** is a highly specific method for detecting HIV, but it is expensive, time-consuming, and technically demanding.
- It is not routinely used for rapid early diagnosis in neonates due to its practical limitations and the availability of faster, reliable alternatives like PCR.
*Antigen assay for p24*
- The **p24 antigen test** can detect early HIV infection in adults, but its sensitivity is lower in neonates compared to PCR, especially immediately after birth.
- It may not reliably detect infection in newborns due to low viral loads or the presence of maternal antibodies that complex the antigen.
*EIA for HIV antibody*
- An **EIA for HIV antibody** will detect maternal antibodies that have crossed the placenta, meaning it will be positive in nearly all infants born to HIV-positive mothers, regardless of the infant's infection status.
- This test cannot distinguish between passive maternal antibody transfer and true infant infection.
HIV in pregnancy and vertical transmission US Medical PG Question 4: A 27-year-old woman consults an obstetrician as she is planning to become pregnant. She has been diagnosed with HIV (human immunodeficiency virus) infection recently and is currently taking antiretroviral therapy (HAART), as prescribed by her physician. The obstetrician emphasizes the importance of antenatal and peripartum antiretroviral therapy for reducing the risk of mother-to-child transmission of HIV. She also tells the patient that certain antiretroviral drugs, if taken during pregnancy, increase the risk of birth defects in the fetus. She gives a printed list of such drugs to the woman for educational and informational purposes. Which of the following drugs are most likely to be present on the list?
- A. Nelfinavir and Saquinavir
- B. Abacavir and Didanosine
- C. Efavirenz and Delavirdine (Correct Answer)
- D. Lopinavir and Ritonavir
- E. Lamivudine and Nevirapine
HIV in pregnancy and vertical transmission Explanation: ***Efavirenz and Delavirdine***
- Both **efavirenz** and **delavirdine** are **non-nucleoside reverse transcriptase inhibitors (NNRTIs)** and have been associated with an increased risk of **teratogenicity**, particularly neural tube defects, in early pregnancy.
- Due to these potential risks, they are generally **avoided during the first trimester of pregnancy** or when pregnancy is being planned, unless no other suitable alternative exists.
*Nelfinavir and Saquinavir*
- **Nelfinavir** and **saquinavir** are **protease inhibitors (PIs)** which are generally considered **safe for use during pregnancy** and are often part of recommended regimens for HIV-positive pregnant women.
- They do not carry the same significant teratogenic risks as some other antiretroviral drugs.
*Abacavir and Didanosine*
- **Abacavir** and **didanosine** are **nucleoside reverse transcriptase inhibitors (NRTIs)** commonly used in HIV treatment.
- While didanosine can be associated with lactic acidosis and pancreatitis, neither drug is typically considered to significantly increase the risk of birth defects.
*Lopinavir and Ritonavir*
- **Lopinavir/ritonavir** is a commonly used **protease inhibitor (PI)** combination that is generally considered **safe and effective for use throughout pregnancy** to prevent mother-to-child transmission.
- It does not have known significant teratogenic effects.
*Lamivudine and Nevirapine*
- **Lamivudine** is an **NRTI** and **nevirapine** is an **NNRTI**. Lamivudine is generally considered safe during pregnancy.
- Nevirapine is used in pregnancy, particularly if started after the first trimester, and generally has a more favorable safety profile regarding birth defects compared to efavirenz and delavirdine.
HIV in pregnancy and vertical transmission US Medical PG Question 5: A 23-year-old primigravid woman comes to the physician at 36 weeks' gestation for her first prenatal visit. She confirmed the pregnancy with a home urine pregnancy kit a few months ago but has not yet followed up with a physician. She takes no medications. Vital signs are within normal limits. Pelvic examination shows a uterus consistent in size with a 36-week gestation. Laboratory studies show:
Hemoglobin 10.6 g/dL
Serum
Glucose 88 mg/dL
Hepatitis B surface antigen negative
Hepatitis C antibody negative
HIV antibody positive
HIV load 11,000 copies/mL (N < 1000 copies/mL)
Ultrasonography shows an intrauterine fetus consistent in size with a 36-week gestation. Which of the following is the most appropriate next step in management of this patient?
- A. Intrapartum zidovudine and vaginal delivery when labor occurs
- B. Intrapartum zidovudine and cesarean delivery at 38 weeks' gestation
- C. Start cART and prepare for vaginal delivery at 38 weeks' gestation
- D. Conduct cesarean delivery immediately
- E. Start cART and schedule cesarean delivery at 38 weeks' gestation (Correct Answer)
HIV in pregnancy and vertical transmission Explanation: ***Start cART and schedule cesarean delivery at 38 weeks' gestation***
- This patient presents at 36 weeks with a **newly diagnosed HIV infection** and a **viral load of 11,000 copies/mL**, which is considered high. Starting **combination antiretroviral therapy (cART)** immediately is crucial to reduce the viral load and the risk of **mother-to-child transmission (MTCT)**.
- For patients with **HIV viral loads > 1,000 copies/mL** near term, a **scheduled cesarean delivery at 38 weeks** is recommended to minimize fetal exposure to maternal blood and secretions during labor, further reducing the risk of MTCT.
*Intrapartum zidovudine and vaginal delivery when labor occurs*
- This approach is appropriate for HIV-positive mothers with a **low viral load (< 1,000 copies/mL)** at or near delivery, as a scheduled cesarean section would not significantly further reduce the risk of transmission.
- Given the patient's **high viral load (11,000 copies/mL)**, **only intrapartum zidovudine** would be insufficient to adequately reduce the risk of MTCT during a vaginal delivery.
*Intrapartum zidovudine and cesarean delivery at 38 weeks' gestation*
- While a **scheduled cesarean delivery at 38 weeks** is indicated for a high viral load, simply administering **intrapartum zidovudine without prior cART** misses the opportunity to significantly reduce viral load before delivery.
- Starting **cART immediately** offers the best chance to lower viral load and optimize outcomes for both mother and child, which is superior to only intrapartum prophylaxis.
*Start cART and prepare for vaginal delivery at 38 weeks' gestation*
- Starting **cART is essential**, but preparing for a vaginal delivery with a **viral load of 11,000 copies/mL** at 36 weeks is inappropriate.
- A **high viral load** necessitates a ** scheduled cesarean delivery** to minimize the risk of MTCT, regardless of cART initiation at this late stage.
*Conduct cesarean delivery immediately*
- While immediate action is needed, an **emergency cesarean delivery** is not indicated at 36 weeks unless there are other obstetric complications or rapid deterioration.
- The primary goal is to **reduce viral load through cART** and then perform a **scheduled cesarean at 38 weeks**, balancing safety for both mother and fetus with the greatest reduction in HIV transmission risk.
HIV in pregnancy and vertical transmission US Medical PG Question 6: A 29-year-old woman tests positive for HIV during pregnancy screening. She is concerned about transmission to her baby. Which of the following interventions most significantly reduces the risk of vertical transmission?
- A. Avoiding breastfeeding only
- B. Cesarean delivery only
- C. Antiretroviral therapy during pregnancy and labor (Correct Answer)
- D. Maternal immunization
HIV in pregnancy and vertical transmission Explanation: ***Antiretroviral therapy during pregnancy and labor***
- **Antiretroviral therapy (ART)** significantly reduces the **viral load** in the mother, thereby minimizing the risk of HIV transmission to the fetus during pregnancy and childbirth.
- When combined with other strategies like **cesarean section** and **avoidance of breastfeeding** in developed countries, ART can reduce vertical transmission rates to less than 1%.
*Avoiding breastfeeding only*
- While **avoiding breastfeeding** is a crucial intervention, especially in settings where safe alternatives are available, it addresses only one mode of transmission (postnatal).
- It does not prevent **in-utero** or **intrapartum transmission**, which are primary routes of vertical transmission if the viral load is high.
*Cesarean delivery only*
- **Cesarean delivery** can reduce the risk of transmission by avoiding exposure to maternal blood and secretions during vaginal delivery.
- However, it is most effective when the maternal **viral load is high** and is often combined with ART for maximum efficacy; it's less effective without ART.
*Maternal immunization*
- **Maternal immunization** involves administering vaccines to the mother to protect against specific infections, primarily bacterial or viral diseases like influenza or tetanus.
- It has **no direct impact** on the risk of HIV transmission, as there is currently no vaccine available for HIV.
HIV in pregnancy and vertical transmission US Medical PG Question 7: A 24-hour-old newborn presents to the emergency department after a home birth because of fever, irritability alternating with lethargy, and poor feeding. The patient’s mother says symptoms acutely onset 12 hours ago and have not improved. No significant past medical history. His mother did not receive any prenatal care, and she had rupture of membranes 20 hours prior to delivery. His vital signs include: heart rate 150/min, respiratory rate 65/min, temperature 39.0°C (102.2°F), and blood pressure 60/40 mm Hg. On physical examination, the patient has delayed capillary refill. Laboratory studies show a pleocytosis and a low glucose level in the patient’s cerebrospinal fluid. Which of the following is the most likely causative organism for this patient’s condition?
- A. Group A Streptococcus
- B. Enterovirus
- C. Group B Streptococcus (Correct Answer)
- D. Streptococcus pneumoniae
- E. Cryptococcus neoformans
HIV in pregnancy and vertical transmission Explanation: ***Group B Streptococcus***
- This newborn presents with **fever, irritability/lethargy, poor feeding**, and signs of **sepsis (tachycardia, tachypnea, hypotension, delayed capillary refill)**, along with **abnormal CSF (pleocytosis, low glucose)**, indicating **neonatal meningitis**.
- **Group B Streptococcus (GBS)** is the **most common cause of early-onset neonatal sepsis and meningitis**, especially with risk factors such as **lack of prenatal care** and **prolonged rupture of membranes (>18 hours)**, as seen in this case.
*Group A Streptococcus*
- While Group A Streptococcus can cause severe infections, it is an **uncommon cause of neonatal sepsis and meningitis** compared to GBS.
- More typically associated with **pharyngitis, impetigo, and necrotizing fasciitis** in older children and adults.
*Enterovirus*
- Enteroviruses are a common cause of **viral meningitis in neonates and infants**, but typically present with a **lymphocytic pleocytosis** and **normal CSF glucose**, in contrast to the features (pleocytosis, low glucose) seen here.
- While fever and irritability can be present, the CSF findings point more towards a bacterial infection.
*Streptococcus pneumoniae*
- *Streptococcus pneumoniae* can cause bacterial meningitis but is **less common in the immediate neonatal period** (first 7 days of life) compared to GBS.
- Risk factors often include **preterm birth** or **underlying immune deficiencies**, which are not specified here.
*Cryptococcus neoformans*
- *Cryptococcus neoformans* is an **opportunistic fungal pathogen** that typically causes meningitis in **immunocompromised individuals**, such as those with HIV/AIDS.
- It is **extremely rare** in immunocompetent newborns and would not be the most likely cause in this clinical scenario.
HIV in pregnancy and vertical transmission US Medical PG Question 8: A 2900-g (6.4-lb) male newborn is delivered at term to a 29-year-old primigravid woman. His mother had no routine prenatal care. She reports that the pregnancy was uncomplicated apart from a 2-week episode of a low-grade fever and swollen lymph nodes during her early pregnancy. She has avoided all routine vaccinations because she believes that “natural immunity is better.” The newborn is at the 35th percentile for height, 15th percentile for weight, and 3rd percentile for head circumference. Fundoscopic examination shows inflammation of the choroid and the retina in both eyes. A CT scan of the head shows diffuse intracranial calcifications and mild ventriculomegaly. Prenatal avoidance of which of the following would have most likely prevented this newborn's condition?
- A. Undercooked pork (Correct Answer)
- B. Raw cow milk products
- C. Mosquito bites
- D. Exposure to unvaccinated children
- E. Unprotected sexual intercourse
HIV in pregnancy and vertical transmission Explanation: ***Undercooked pork***
- The constellation of **hydrocephalus**, **chorioretinitis**, and **intracranial calcifications** (classic triad) in a newborn, coupled with maternal symptoms of fever and lymphadenopathy, is highly suggestive of **congenital toxoplasmosis**.
- **Toxoplasmosis** is caused by the parasite *Toxoplasma gondii*, which can be acquired by consuming **undercooked meat** (especially pork and lamb) or exposure to **contaminated cat feces/litter**.
- Avoiding undercooked meat during pregnancy is a key preventive measure.
*Raw cow milk products*
- While raw milk can transmit various infections (e.g., *Listeria*, *Brucella*, *E. coli*), it is not a typical source of **congenital toxoplasmosis**.
- **Listeriosis** can cause congenital infection, but the symptoms (e.g., sepsis, granulomatosis infantiseptica) differ from those described.
*Mosquito bites*
- Mosquitoes are vectors for diseases like **Zika virus**, **Malaria**, and **Dengue fever**, which can affect newborns.
- **Congenital Zika syndrome** can cause microcephaly, but typically not the classic triad of toxoplasmosis, and malaria presents with fever and hemolytic anemia.
*Exposure to unvaccinated children*
- This primarily refers to common childhood infections like **measles**, **rubella**, and **chickenpox**.
- **Congenital rubella syndrome** can cause cataracts, heart defects, and sensorineural hearing loss, but not the specific triad of chorioretinitis, hydrocephalus, and intracranial calcifications.
*Unprotected sexual intercourse*
- This is a route for sexually transmitted infections (STIs), such as **HIV**, **syphilis**, and **gonorrhea**, which can be transmitted vertically.
- **Congenital syphilis** can cause bone abnormalities, rash, and hepatosplenomegaly, but not the distinct neurological and ocular findings seen here.
HIV in pregnancy and vertical transmission US Medical PG Question 9: Four scientists were trying to measure the effect of a new inhibitor X on the expression levels of transcription factor, HNF4alpha. They measured the inhibition levels by using RT-qPCR. In short they converted the total mRNA of the cells to cDNA (RT part), and used PCR to amplify the cDNA quantifying the amplification with a dsDNA binding dye (qPCR part). Which of the following group characteristics contains a virus(es) that has the enzyme necessary to convert the mRNA to cDNA used in the above scenario?
- A. Enveloped, dimeric (+) ssRNA (Correct Answer)
- B. Enveloped, circular (-) ssRNA
- C. Nonenveloped, (+) ssRNA
- D. Nonenveloped, ssDNA
- E. Nonenveloped, circular dsDNA
HIV in pregnancy and vertical transmission Explanation: ***Enveloped, dimeric (+) ssRNA***
- This group describes **retroviruses**, which possess the enzyme **reverse transcriptase**.
- **Reverse transcriptase** is essential for converting their **RNA genome** into **cDNA**, a process analogous to the RT step in RT-qPCR.
- Examples include **HIV**, which is tagged to this topic.
*Enveloped, circular (-) ssRNA*
- This description does not accurately represent a major viral family.
- Most enveloped negative-sense RNA viruses have **linear or segmented genomes** (e.g., **Orthomyxoviruses**, **Bunyaviruses**), not circular.
- These viruses replicate using an **RNA-dependent RNA polymerase** to synthesize mRNA from their negative-sense RNA genome.
- They do not inherently carry or require **reverse transcriptase** for their life cycle.
*Nonenveloped, (+) ssRNA*
- These viruses, like **Picornaviruses**, directly use their positive-sense RNA as mRNA and replicate via an **RNA-dependent RNA polymerase**.
- They do not possess **reverse transcriptase** for cDNA synthesis.
*Nonenveloped, ssDNA*
- Viruses with a **single-stranded DNA genome**, such as **Parvoviruses**, replicate by first synthesizing a double-stranded DNA intermediate.
- Their replication machinery does not involve **reverse transcriptase** to convert RNA to DNA.
*Nonenveloped, circular dsDNA*
- Viruses in this group, like **Papillomaviruses** and **Polyomaviruses**, have a circular double-stranded DNA genome and replicate within the host nucleus using the host's DNA polymerase.
- They do not utilize or encode **reverse transcriptase** for their replication cycle.
HIV in pregnancy and vertical transmission US Medical PG Question 10: A 44-year-old with a past medical history significant for human immunodeficiency virus infection presents to the emergency department after he was found to be experiencing worsening confusion. The patient was noted to be disoriented by residents and staff at the homeless shelter where he resides. On presentation he reports headache and muscle aches but is unable to provide more information. His temperature is 102.2°F (39°C), blood pressure is 112/71 mmHg, pulse is 115/min, and respirations are 24/min. Knee extension with hips flexed produces significant resistance and pain. A lumbar puncture is performed with the following results:
Opening pressure: Normal
Fluid color: Clear
Cell count: Increased lymphocytes
Protein: Slightly elevated
Which of the following is the most likely cause of this patient's symptoms?
- A. Herpes simplex virus
- B. Group B streptococcus
- C. Cryptococcus (Correct Answer)
- D. Tuberculosis
- E. Neisseria meningitidis
HIV in pregnancy and vertical transmission Explanation: ***Cryptococcus***
- **Cryptococcus neoformans** is the **most common cause of meningitis** in HIV-positive patients, particularly those with CD4 counts <100 cells/μL.
- The CSF findings are **classic for cryptococcal meningitis**: clear fluid, **lymphocytic pleocytosis**, normal or mildly elevated opening pressure, and **slightly elevated protein** with normal or mildly decreased glucose.
- The patient's **subacute presentation** with confusion, fever, and meningeal signs in the context of **HIV infection** strongly suggests cryptococcal meningitis as the most likely diagnosis.
- Diagnosis is confirmed with **CSF cryptococcal antigen**, India ink stain, or fungal culture.
*Herpes simplex virus*
- While HSV can cause meningitis or encephalitis, it is **not the most common cause** of meningitis in HIV-positive patients.
- **HSV encephalitis** typically presents with more prominent temporal lobe involvement, including personality changes, seizures, and focal neurological deficits.
- HSV meningitis is more common in **immunocompetent individuals** and would be less likely than cryptococcal infection in an HIV patient.
*Group B streptococcus*
- This causes **bacterial meningitis** with a **neutrophilic predominance** in CSF, not lymphocytic.
- CSF would show **markedly elevated protein**, **decreased glucose**, and cloudy appearance.
- More common in neonates and elderly patients, not typically associated with HIV.
*Neisseria meningitidis*
- This is a cause of **acute bacterial meningitis** with rapid onset and often a **petechial rash**.
- CSF would show **neutrophilic predominance**, **high protein**, **low glucose**, and turbid appearance.
- The lymphocytic pleocytosis rules out typical bacterial meningitis.
*Tuberculosis*
- **Tuberculous (TB) meningitis** is an important consideration in HIV-positive patients and can present with lymphocytic pleocytosis.
- However, TB meningitis typically shows **markedly elevated protein** (often >100 mg/dL, not "slightly elevated"), **low glucose** (<45 mg/dL), and may have a "spider-web clot" on standing CSF.
- The **more subacute to chronic course** (weeks) and absence of very high protein make TB less likely than cryptococcal meningitis in this acute presentation.
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