Neonatal infections Practice Questions

Q: A 3-year-old boy is referred for evaluation of short stature and dysmorphic features. The growth chart image provided shows his height consistently tracking below the 3rd percentile since 12 months of age with normal head circumference. On examination he has a broad forehead, hypertelorism, low-set posteriorly rotated ears, a webbed neck, widely spaced nipples, and a harsh systolic murmur loudest at the left upper sternal border. Karyotype returns as 46,XY. Which of the following additional findings would most strongly support the unifying diagnosis in this child?

Pulmonary valve stenosis and mutation in the PTPN11 gene. ***Pulmonary valve stenosis and mutation in the PTPN11 gene*** - The clinical features of **short stature**, a **webbed neck**, and **46,XY karyotype** in a male suggest **Noonan syndrome**, which is often caused by a mutation in the **PTPN11 gene**. - **Pulmonary valve stenosis** is the most common cardiac anomaly in Noonan syndrome and accounts for the **systolic murmur** heard at the **left upper sternal border**. *Bicuspid aortic valve and coarctation of the aorta* - These cardiac anomalies are typically associated with **Turner syndrome**, which presents with similar dysmorphic features but a **45,X** karyotype. - Because this patient has a **46,XY karyotype**, Noonan syndrome is the diagnosis, and it typically affects the **right heart** rather than the left. *Atrioventricular septal defect and duodenal atresia* - These findings are classical associations with **Trisomy 21 (Down syndrome)**, not Noonan syndrome. - This patient lacks the characteristic **upslanting palpebral fissures** and **hypotonia** typical of Down syndrome. *Supravalvular aortic stenosis and hypercalcemia* - This combination is pathognomonic for **Williams syndrome**, which is caused by a microdeletion on **chromosome 7**. - Williams syndrome is characterized by "elfin" facies and an **outgoing personality**, which does not align with the widely spaced nipples and webbed neck seen here. *Ventricular septal defect and single palmar crease* - While a **single palmar crease** can be found in Noonan syndrome, it is more commonly associated with **Trisomy 21**. - A **ventricular septal defect** is a common cardiac finding, but it is not the classic unifying cardiac lesion for Noonan syndrome compared to pulmonary stenosis.

Q: Vitamin K supplementation is given to neonates to prevent _____ .

Hemorrhagic disease of the newborn. ***Hemorrhagic disease of the newborn*** - Neonates have low levels of **vitamin K-dependent clotting factors** (II, VII, IX, X) due to poor placental transfer, sterile gut, and low vitamin K in breast milk. - Vitamin K supplementation at birth prevents potentially life-threatening bleeding episodes, known as **hemorrhagic disease of the newborn (VKDB)**, by ensuring adequate clotting factor production. *Scurvy* - Scurvy is caused by **vitamin C deficiency**, leading to impaired collagen synthesis. - Symptoms include **gingival bleeding**, skin hemorrhages, and poor wound healing, which are distinct from vitamin K deficiency. *Keratomalacia* - Keratomalacia is a severe eye condition resulting from **vitamin A deficiency**, characterized by drying and clouding of the cornea. - It leads to **blindness** and is not related to vitamin K metabolism. *Breast milk jaundice* - Breast milk jaundice is a common and usually benign condition in neonates where **breast milk components** interfere with bilirubin metabolism, prolonging physiological jaundice. - It is not prevented by vitamin K and is entirely distinct from coagulation disorders. *Rickets* - Rickets is caused by **vitamin D deficiency**, resulting in defective bone mineralization and skeletal deformities. - Clinical features include **bowed legs**, rachitic rosary, and delayed fontanelle closure, which are unrelated to coagulation or vitamin K.

Q: A mother delivers in a rural area under the guidance of a skilled care attendant. Which of the following statements is incorrect regarding the care provided by the skilled care attendant at birth?

Bathe the baby with warm water. ***Bathe the baby with warm water*** - **Delaying the first bath** for at least 6-24 hours after birth is recommended to prevent **hypothermia** and promote **skin-to-skin contact** for bonding and breastfeeding. - Early bathing can remove **vernix caseosa**, which provides natural antimicrobial protection and moisturization to the newborn's skin. *Start breastfeeding as early as possible* - **Early initiation of breastfeeding**, ideally within the first hour of birth, is crucial for both mother and baby. - It promotes **uterine contractions** to prevent **postpartum hemorrhage** and provides the newborn with **colostrum**, rich in antibodies. *Cover the baby's head and body* - Covering the newborn's head and body is essential to prevent **heat loss** and maintain a stable **body temperature**, immediately after birth. - Newborns are highly susceptible to **hypothermia** due to their large surface area to mass ratio and immature thermoregulation. *Clear the eyes with a sterile swab* - Clearing the newborn's eyes with a sterile swab is a standard part of immediate newborn care to remove any **mucus or blood** that might have entered during delivery. - This helps prevent **ophthalmia neonatorum**, especially if the mother has an infection like gonorrhea or chlamydia. *Dry the baby thoroughly and stimulate breathing* - **Drying the baby immediately** after birth is a critical first step in newborn resuscitation and care. - It helps prevent **hypothermia** and provides **tactile stimulation** to initiate breathing and crying, which is essential for transitioning from fetal to neonatal circulation.

Q: A baby presents with hydrocephalus, intracranial calcifications, and chorioretinitis. What is the most probable diagnosis?

Toxoplasmosis. **Toxoplasmosis** - The classic triad of **hydrocephalus**, **intracranial calcifications**, and **chorioretinitis** is highly characteristic of congenital toxoplasmosis. - These findings result from the parasite's invasive nature and predilection for the central nervous system and eyes of the developing fetus. - Calcifications in toxoplasmosis are typically **diffuse and scattered** throughout the brain parenchyma. *Syphilis* - Congenital syphilis typically presents with **rhinitis**, **skin rash**, **hepatosplenomegaly**, and **bone abnormalities** (e.g., periostitis, saber shins). - While neurological complications can occur, the specific triad of hydrocephalus, intracranial calcifications, and chorioretinitis is not characteristic. *Cytomegalovirus (CMV) infection* - Congenital CMV can cause **periventricular calcifications** (not diffuse calcifications), **microcephaly**, and **sensorineural hearing loss**. - While chorioretinitis can occur, hydrocephalus is less frequent, and the calcification pattern differs from toxoplasmosis (CMV shows periventricular pattern vs. diffuse in toxoplasmosis). *Rubella* - Congenital rubella syndrome is known for causing the classic triad of **cataracts**, **sensorineural hearing loss**, and **congenital heart defects** (e.g., patent ductus arteriosus, pulmonary artery stenosis). - Intracranial calcifications and hydrocephalus are not typical presentations of congenital rubella. *Herpes Simplex Virus (HSV) infection* - Neonatal HSV typically presents with **vesicular skin lesions**, **encephalitis**, and **disseminated disease** affecting liver and lungs. - While HSV can cause encephalitis with brain involvement, the classic triad of hydrocephalus, diffuse intracranial calcifications, and chorioretinitis is not characteristic of HSV infection.

Question 1

A 4-year-old girl is brought to the clinic for a well-child visit. Her growth chart is shown. She was born at term with a birth weight of 3.4 kg. Her weight at 12 months was at the 50th percentile, at 24 months at the 25th percentile, and today her weight plots below the 3rd percentile. Her length has followed the 25th percentile consistently. Her parents report she has had three to four loose, foul-smelling, greasy stools per day since she began eating gluten-containing foods at 12 months. Laboratory studies show hemoglobin 9.8 g/dL with microcytic anemia, albumin 2.8 g/dL, and zinc level below normal. Anti-tissue transglutaminase IgA antibodies are elevated. Which of the following is the most likely primary etiology of her growth pattern?

Accepted Answer

Celiac disease causing malabsorptive failure to thrive

Answer

Constitutional growth delay with familial short stature

Answer

Inadequate caloric and protein intake with micronutrient deficiency

Answer

Growth hormone deficiency presenting in early childhood

Answer

Iron-deficiency anemia as the primary cause of poor weight gain

Question 2

A 3-year-old boy is referred for evaluation of short stature and dysmorphic features. The growth chart image provided shows his height consistently tracking below the 3rd percentile since 12 months of age with normal head circumference. On examination he has a broad forehead, hypertelorism, low-set posteriorly rotated ears, a webbed neck, widely spaced nipples, and a harsh systolic murmur loudest at the left upper sternal border. Karyotype returns as 46,XY. Which of the following additional findings would most strongly support the unifying diagnosis in this child?

Accepted Answer

Pulmonary valve stenosis and mutation in the PTPN11 gene

Answer

Bicuspid aortic valve and coarctation of the aorta

Answer

Atrioventricular septal defect and duodenal atresia

Answer

Supravalvular aortic stenosis and hypercalcemia

Answer

Ventricular septal defect and single palmar crease

Question 3

Vitamin K supplementation is given to neonates to prevent _____ .

Accepted Answer

Hemorrhagic disease of the newborn

Answer

Scurvy

Answer

Keratomalacia

Answer

Breast milk jaundice

Answer

Rickets

Question 4

A mother delivers in a rural area under the guidance of a skilled care attendant. Which of the following statements is incorrect regarding the care provided by the skilled care attendant at birth?

Accepted Answer

Bathe the baby with warm water

Answer

Start breastfeeding as early as possible

Answer

Cover the baby's head and body

Answer

Clear the eyes with a sterile swab

Answer

Dry the baby thoroughly and stimulate breathing

Question 5

A baby presents with hydrocephalus, intracranial calcifications, and chorioretinitis. What is the most probable diagnosis?

Accepted Answer

Toxoplasmosis

Answer

Syphilis

Answer

Cytomegalovirus (CMV) infection

Answer

Rubella

Answer

Herpes Simplex Virus (HSV) infection

Neonatal infections — MCQs

Neonatal infections — MCQs

On this page

Practice by Chapter

Want unlimited practice?