Two days after delivery, a newborn develops a red, irritated eye with yellow discharge. She was born at 39 weeks' gestation to a 28-year-old woman, gravida 1, para 1. Pregnancy and delivery were uncomplicated. The mother had not seen her gynecologist since her first prenatal visit. The newborn's temperature is 37.2°C (99.0°F), pulse is 140/min, respirations are 42/min, and blood pressure is 73/53 mm Hg. Ophthalmic examination shows eyelid edema, conjunctival injection, and copious yellow mucopurulent discharge from the right eye. There is no corneal ulceration or evidence of keratitis. Funduscopic examination is normal. The diagnosis is confirmed and appropriate treatment is administered. Which of the following is most likely to have prevented this patient's condition?
Q62
A baby is born after the 32nd gestational week by cesarean delivery. The mother suffered from gestational diabetes; however, she had no other pregnancy-related diseases and was otherwise healthy. The baby has a blood pressure of 100/58 mm Hg, heart rate of 104/min, and oxygen saturation of 88%. The child has tachypnea, subcostal and intercostal retractions, nasal flaring, and cyanosis. The cyanosis is responding well to initial administration of oxygen. The nasogastric tube was positioned without problems. Which of the following is the most likely diagnosis?
Q63
A 2-week-old female newborn is brought to the physician because of increasing yellow discoloration of her eyes and skin for 2 days. She was born at 39 weeks' gestation and weighed 3066 g (6 lb 12 oz); she now weighs 3200 g (7 lb 1 oz). She is exclusively breastfed. Her older brother died 3 months after liver surgery. Her temperature is 37.1°C (98.8°F), pulse is 145/min, and respirations are 40/min. Examination shows yellow discoloration extending to the palms and soles. The liver is palpated 1 cm below the right costal margin. Laboratory studies show:
Hematocrit 51%
Serum
Bilirubin
Total 16.1 mg/dL
Direct 0.7 mg/dL
Alkaline phosphatase 22 U/L
AST 12 U/L
ALT 12 U/L
Which of the following is the most likely diagnosis?
Q64
Three days after delivery, a 1100-g (2-lb 7-oz) newborn has a tonic seizure that lasts for 25 seconds. She has become increasingly lethargic over the past 18 hours. She was born at 31 weeks' gestation. Antenatal period was complicated by chorioamnionitis. Apgar scores were 3 and 6 at 1 and 5 minutes, respectively. She appears ill. Her pulse is 123/min, respirations are 50/min and irregular, and blood pressure is 60/30 mm Hg. Examination shows a tense anterior fontanelle. The pupils are equal and react sluggishly to light. Examination shows slow, conjugate back and forth movements of the eyes. Muscle tone is decreased in all extremities. The lungs are clear to auscultation. Which of the following is the most likely diagnosis?
Q65
A 5-day-old male newborn is brought to the physician by his mother because of yellowish discoloration of the skin for 1 day. The discoloration first appeared on his face and then spread to his trunk. There have been no changes in his bowel habits or urination. He was born at 38 weeks' gestation via uncomplicated vaginal delivery. He is exclusively breastfed every 2–3 hours. Examination shows scleral icterus and jaundice of the face, chest, and abdomen. Laboratory studies show:
Hemoglobin 17.6 g/dL
Reticulocytes 0.3%
Maternal blood group A, Rh-negative
Fetal blood group 0, Rh-positive
Serum
Bilirubin, total 7 mg/dL
Direct 0.6 mg/dL
Free T4 12 μg/dL
Which of the following is the most likely diagnosis?
Q66
An otherwise healthy, exclusively breastfed 4-day-old neonate is brought to the physician because of yellowing of his skin and eyes. His urine has been clear and stools have been normal. He was born at term by vacuum-assisted delivery and weighed 4000 g (8 lb 8 oz). Pregnancy was complicated by gestational diabetes mellitus. His older sibling had jaundice in the neonatal period. Vital signs are within normal limits. He appears alert and comfortable. Physical examination shows jaundice of the skin and sclerae. The liver is palpated 1 cm below the right costal margin. Laboratory studies show:
Hemoglobin 17 g/dl
Reticulocyte count 0.5 %
Total bilirubin 21.2 mg/dl
Direct bilirubin 2 mg/dl
Indirect bilirubin 19.1 mg/dl
Coombs test Negative
Which of the following is the most appropriate next step in management?
Q67
A neonate born at 33 weeks is transferred to the NICU after a complicated pregnancy and C-section. A week after being admitted, he developed a fever and became lethargic and minimally responsive to stimuli. A lumbar puncture is performed that reveals the following:
Appearance Cloudy
Protein 64 mg/dL
Glucose 22 mg/dL
Pressure 330 mm H20
Cells 295 cells/mm³ (> 90% PMN)
A specimen is sent to microbiology and reveals gram-negative rods. Which of the following is the next appropriate step in management?
Q68
A 2-week-old female newborn is brought to the physician for the evaluation of red eyes with discharge for 2 days. She was born at 39 weeks' gestation to a 22-year-old woman. Pregnancy and delivery were uncomplicated. The mother received irregular prenatal care during the second half of the pregnancy. The newborn weighed 3700 g (8 lb 2.5 oz) at birth, and no congenital anomalies were noted. She currently weighs 4000 g (8 lb 13 oz). Examination of the newborn shows pink skin. The lungs are clear to auscultation. There is mucopurulent discharge in both eyes and mild eyelid swelling. Polymerase chain reaction assay of conjunctival scraping confirms the diagnosis. Which of the following is the most appropriate next step in management?
Q69
A 6-day-old male newborn is brought to the physician by his mother for the evaluation of yellowing of his skin and eyes for one day. The mother reports that she is breastfeeding her son about 7 times per day. She also states that her son had two wet diapers and two bowel movements yesterday. He was born at 38 weeks' gestation and weighed 3500 g (7.7 lb); he currently weighs 3000 g (6.6 lb). His newborn screening was normal. His temperature is 37°C (98.6°F), pulse is 180/min, and blood pressure is 75/45 mm Hg. Physical examination shows scleral icterus, widespread jaundice, and dry mucous membranes. The remainder of the examination shows no abnormalities. Serum studies show:
Bilirubin
Total 9 mg/dL
Direct 0.7 mg/dL
AST 15 U/L
ALT 15 U/L
Which of the following is the most appropriate next step in the management of this patient?
Q70
Three weeks after birth, an infant girl develops episodes of apnea. She has become increasingly lethargic over the past two days, and experienced two episodes of apnea lasting 10 seconds each within the last day. She was born at 31 weeks of gestation and weighed 1600-g (3-lb 8-oz). Apgar scores were 4 and 7 at 1 and 5 minutes, respectively. She takes no medications. Her temperature is 36.7°C (98.0°F), pulse is 185/min, respirations are 60/min and irregular, and blood pressure is 70/35 mm Hg. She appears pale. Physical examination shows no abnormalities. Laboratory studies show a hemoglobin of 6.5 g/dL, a reticulocyte count of 0.5%, and a mean corpuscular volume of 92 μm3. Leukocyte count, platelet count, total bilirubin and indirect bilirubin are all within reference range. Which of the following is the most likely underlying mechanism of this patient's anemia?
Neonatal infections US Medical PG Practice Questions and MCQs
Question 61: Two days after delivery, a newborn develops a red, irritated eye with yellow discharge. She was born at 39 weeks' gestation to a 28-year-old woman, gravida 1, para 1. Pregnancy and delivery were uncomplicated. The mother had not seen her gynecologist since her first prenatal visit. The newborn's temperature is 37.2°C (99.0°F), pulse is 140/min, respirations are 42/min, and blood pressure is 73/53 mm Hg. Ophthalmic examination shows eyelid edema, conjunctival injection, and copious yellow mucopurulent discharge from the right eye. There is no corneal ulceration or evidence of keratitis. Funduscopic examination is normal. The diagnosis is confirmed and appropriate treatment is administered. Which of the following is most likely to have prevented this patient's condition?
A. IV ceftriaxone administered to the infant
B. Oral doxycycline administered to the mother
C. Oral erythromycin administered to the infant
D. Topical erythromycin administered to the infant (Correct Answer)
E. Oral amoxicillin administered to the mother
Explanation: ***Topical erythromycin administered to the infant***
- This clinical presentation of **red, irritated eye** with **copious yellow mucopurulent discharge** developing within days of birth is characteristic of **gonococcal ophthalmia neonatorum**.
- **Prophylactic topical erythromycin ophthalmic ointment** given shortly after birth is highly effective in preventing this condition by eradicating *Neisseria gonorrhoeae* and *Chlamydia trachomatis* from the conjunctiva.
*IV ceftriaxone administered to the infant*
- **IV ceftriaxone** is the appropriate treatment for **gonococcal ophthalmia neonatorum** once it has developed, but it is not a primary preventative measure.
- While it resolves the active infection, it does not prevent the initial colonization and irritation that topical prophylaxis aims to avoid.
*Oral doxycycline administered to the mother*
- **Doxycycline** is an antibiotic used to treat chlamydial and gonococcal infections in adults.
- Administering it to the mother *before* delivery, if she had an undiagnosed infection, could prevent vertical transmission, but it is not the standard immediate postpartum prophylaxis for the infant’s eyes.
*Oral erythromycin administered to the infant*
- Oral erythromycin is used to treat **chlamydial conjunctivitis** or **pneumonia** in infants, but it is not the standard or most effective prophylactic measure against gonococcal ophthalmia.
- It would be administered for a systemic or more severe localized chlamydial infection, not routine ocular prophylaxis.
*Oral amoxicillin administered to the mother*
- **Amoxicillin** is primarily used to treat bacterial infections like otitis media, sinusitis, or pneumonia.
- It is **not effective** against *Neisseria gonorrhoeae* or *Chlamydia trachomatis*, and therefore would not prevent ophthalmia neonatorum.
Question 62: A baby is born after the 32nd gestational week by cesarean delivery. The mother suffered from gestational diabetes; however, she had no other pregnancy-related diseases and was otherwise healthy. The baby has a blood pressure of 100/58 mm Hg, heart rate of 104/min, and oxygen saturation of 88%. The child has tachypnea, subcostal and intercostal retractions, nasal flaring, and cyanosis. The cyanosis is responding well to initial administration of oxygen. The nasogastric tube was positioned without problems. Which of the following is the most likely diagnosis?
A. Tracheoesophageal fistula
B. Pneumonia
C. Neonatal respiratory distress syndrome (NRDS) (Correct Answer)
D. Sepsis
E. Congenital heart anomaly with right-to-left shunt
Explanation: ***Neonatal respiratory distress syndrome (NRDS)***
- The premature birth (32nd week), presence of **tachypnea**, **retractions**, **nasal flaring**, **cyanosis** responding to oxygen, and maternal **gestational diabetes** are all highly suggestive of NRDS.
- Maternal gestational diabetes can delay fetal lung maturity, increasing the risk of **surfactant deficiency**, which is the primary cause of NRDS.
*Tracheoesophageal fistula*
- This condition typically presents with **choking**, **coughing**, and **regurgitation** during feeding, often with inability to pass a nasogastric tube into the stomach.
- The successful positioning of the **nasogastric tube** makes this diagnosis less likely.
*Pneumonia*
- While pneumonia can cause respiratory distress, the **early onset** in a premature infant with maternal gestational diabetes points more strongly towards **NRDS**.
- Pneumonia would typically have signs of **infection** such as fever, though early neonatal pneumonia can be atypical.
*Sepsis*
- Sepsis can cause respiratory distress, but it's usually accompanied by other signs of systemic infection, such as **fever or hypothermia**, **lethargy**, and poor feeding and often signs of **circulatory compromise**.
- The clinical picture provided primarily points towards a respiratory rather than a systemic infectious cause primarily.
*Congenital heart anomaly with right-to-left shunt*
- While this can cause **cyanosis** and respiratory distress, the prompt response to oxygen management makes a significant right-to-left shunt less likely.
- A significant right-to-left shunt would typically cause **cyanosis** that is refractory to oxygen administration.
Question 63: A 2-week-old female newborn is brought to the physician because of increasing yellow discoloration of her eyes and skin for 2 days. She was born at 39 weeks' gestation and weighed 3066 g (6 lb 12 oz); she now weighs 3200 g (7 lb 1 oz). She is exclusively breastfed. Her older brother died 3 months after liver surgery. Her temperature is 37.1°C (98.8°F), pulse is 145/min, and respirations are 40/min. Examination shows yellow discoloration extending to the palms and soles. The liver is palpated 1 cm below the right costal margin. Laboratory studies show:
Hematocrit 51%
Serum
Bilirubin
Total 16.1 mg/dL
Direct 0.7 mg/dL
Alkaline phosphatase 22 U/L
AST 12 U/L
ALT 12 U/L
Which of the following is the most likely diagnosis?
A. Biliary atresia
B. Physiologic neonatal jaundice
C. Breastfeeding failure jaundice
D. Isoimmune mediated hemolysis
E. Breast milk jaundice (Correct Answer)
Explanation: ***Breast milk jaundice***
- This diagnosis is supported by the **exclusive breastfeeding** of the 2-week-old infant and the **late onset** of jaundice (peaking around 2-3 weeks of life).
- The elevated **total bilirubin** with a normal direct bilirubin (indicating **unconjugated hyperbilirubinemia**) and normal liver enzymes are characteristic findings.
- The infant has appropriate **weight gain**, indicating adequate feeding and ruling out breastfeeding failure.
*Biliary atresia*
- This condition presents with **conjugated (direct) hyperbilirubinemia**, typically with direct bilirubin levels **>20% of total bilirubin** or >1 mg/dL, which is not seen here (0.7 mg/dL).
- It would also involve elevated **alkaline phosphatase** and **liver transaminases**, which are normal in this patient.
- The family history of a sibling dying after liver surgery may suggest biliary atresia in that sibling, but this patient's presentation with **unconjugated hyperbilirubinemia** and **normal liver function** excludes this diagnosis.
*Physiologic neonatal jaundice*
- This type of jaundice typically appears after the first 24 hours of life but resolves within the **first week** in term infants.
- The patient is 2 weeks old with **increasing jaundice**, which is inconsistent with the natural resolution of physiologic jaundice.
*Breastfeeding failure jaundice*
- This usually occurs in the **first week of life** due to insufficient milk intake, leading to dehydration and increased enterohepatic circulation of bilirubin.
- The infant's **weight gain** (3066g to 3200g over 2 weeks) indicates adequate feeding, making breastfeeding failure unlikely.
*Isoimmune mediated hemolysis*
- This would present with jaundice in the **first 24-48 hours of life** and is characterized by rapidly rising bilirubin, anemia, and often a **positive Coombs test**.
- This patient's hematocrit is normal (51%), and the **late onset** of jaundice does not fit with hemolytic disease.
Question 64: Three days after delivery, a 1100-g (2-lb 7-oz) newborn has a tonic seizure that lasts for 25 seconds. She has become increasingly lethargic over the past 18 hours. She was born at 31 weeks' gestation. Antenatal period was complicated by chorioamnionitis. Apgar scores were 3 and 6 at 1 and 5 minutes, respectively. She appears ill. Her pulse is 123/min, respirations are 50/min and irregular, and blood pressure is 60/30 mm Hg. Examination shows a tense anterior fontanelle. The pupils are equal and react sluggishly to light. Examination shows slow, conjugate back and forth movements of the eyes. Muscle tone is decreased in all extremities. The lungs are clear to auscultation. Which of the following is the most likely diagnosis?
A. Intraventricular hemorrhage (Correct Answer)
B. Spinal muscular atrophy
C. Galactosemia
D. Congenital hydrocephalus
E. Phenylketonuria
Explanation: ***Intraventricular hemorrhage***
- The combination of **prematurity** (31 weeks' gestation, 1100g), **tonic seizures**, increasing **lethargy**, tense **anterior fontanelle**, **sluggishly reactive pupils**, and **slow conjugate back-and-forth eye movements** (suggesting brainstem involvement from increased intracranial pressure) are classical signs of intraventricular hemorrhage (IVH) in a neonate.
- **IVH** is common in premature infants due to the fragility of germinal matrix vessels and can manifest acutely with neurological deterioration and increased intracranial pressure, typically within the first 72 hours of life.
- While maternal **chorioamnionitis** and low Apgar scores raise concern for neonatal sepsis/meningitis, the specific **ocular movement pattern** and acute neurological signs on day 3 are more characteristic of IVH in this extremely premature infant.
*Spinal muscular atrophy*
- This is a **neuromuscular genetic disorder** characterized by progressive muscle weakness and hypotonia due to anterior horn cell degeneration.
- It would typically present with **decreased muscle tone but without acute neurological signs** like seizures, tense fontanelle, or sluggish pupillary responses.
- Does not cause acute-onset seizures or rapidly progressing lethargy in the neonatal period.
*Galactosemia*
- This is a **metabolic disorder** that presents with symptoms such as **vomiting, jaundice, hepatomegaly**, and **sepsis-like symptoms** upon introduction of lactose-containing feeds (breast milk or regular formula), typically after several days of feeding.
- While it can cause lethargy and seizures, the acute neurological findings including **tense fontanelle** and **abnormal eye movements** in the immediate postnatal period of a premature infant more strongly suggest an anatomical/structural etiology like IVH.
*Congenital hydrocephalus*
- While **hydrocephalus** can cause a **tense fontanelle** and seizures, the **acute onset** of symptoms (day 3 of life with rapid deterioration over 18 hours following a specific tonic seizure) in an extremely premature infant strongly suggests an **acute hemorrhagic event** rather than congenital hydrocephalus.
- Congenital hydrocephalus typically presents with **progressively enlarging head circumference** over time, rather than such acute neurological deterioration in the first 72 hours of life.
- IVH can lead to secondary post-hemorrhagic hydrocephalus, but the acute presentation favors primary IVH.
*Phenylketonuria*
- This is a **metabolic disorder** caused by phenylalanine hydroxylase deficiency that, if untreated, leads to **intellectual disability** and seizures.
- Symptoms typically manifest **several months after birth** (usually 3-6 months) as phenylalanine accumulates, and are not associated with acute neonatal neurological distress like tense fontanelle, abnormal eye movements, or acute lethargy in the first few days of life.
- Would not explain the acute deterioration on day 3 of life in this clinical context.
Question 65: A 5-day-old male newborn is brought to the physician by his mother because of yellowish discoloration of the skin for 1 day. The discoloration first appeared on his face and then spread to his trunk. There have been no changes in his bowel habits or urination. He was born at 38 weeks' gestation via uncomplicated vaginal delivery. He is exclusively breastfed every 2–3 hours. Examination shows scleral icterus and jaundice of the face, chest, and abdomen. Laboratory studies show:
Hemoglobin 17.6 g/dL
Reticulocytes 0.3%
Maternal blood group A, Rh-negative
Fetal blood group 0, Rh-positive
Serum
Bilirubin, total 7 mg/dL
Direct 0.6 mg/dL
Free T4 12 μg/dL
Which of the following is the most likely diagnosis?
A. Biliary atresia
B. Dubin-Johnson syndrome
C. Physiological neonatal jaundice (Correct Answer)
D. Rhesus incompatibility
E. Congenital hypothyroidism
Explanation: ***Physiological neonatal jaundice***
- This newborn’s jaundice is **unconjugated (indirect) hyperbilirubinemia**, indicated by a total bilirubin of 7 mg/dL and a direct bilirubin of 0.6 mg/dL (direct bilirubin is less than 20% of total).
- The onset of jaundice after 24 hours of age (day 4-5), peak at 3-5 days, resolution within 1-2 weeks, and the absence of other concerning symptoms in an otherwise healthy term infant strongly suggest **physiological jaundice**.
*Biliary atresia*
- Characterized by **conjugated (direct) hyperbilirubinemia**, often with dark urine and pale stools, which are not present here.
- Typically presents later, around 2-4 weeks of age, and would show a higher direct bilirubin percentage.
*Dubin-Johnson syndrome*
- An **autosomal recessive disorder** causing conjugated hyperbilirubinemia due to a defect in bilirubin excretion into bile.
- Presents with a high proportion of **direct bilirubin**, not seen in this case.
*Rhesus incompatibility*
- Would cause **hemolytic anemia** with jaundice typically appearing within the first 24 hours of life and often severe.
- The **normal reticulocyte count (0.3%)** and stable hemoglobin (17.6 g/dL) rule out significant hemolysis.
*Congenital hypothyroidism*
- Can cause **prolonged unconjugated jaundice** (lasting beyond 2 weeks of age) due to delayed bilirubin conjugation.
- However, the free T4 level of 7 µg/dL (assuming it's a TSH newborn screen or a total T4 value given the units) is within or near the normal range, and jaundice in this case is not yet prolonged.
Question 66: An otherwise healthy, exclusively breastfed 4-day-old neonate is brought to the physician because of yellowing of his skin and eyes. His urine has been clear and stools have been normal. He was born at term by vacuum-assisted delivery and weighed 4000 g (8 lb 8 oz). Pregnancy was complicated by gestational diabetes mellitus. His older sibling had jaundice in the neonatal period. Vital signs are within normal limits. He appears alert and comfortable. Physical examination shows jaundice of the skin and sclerae. The liver is palpated 1 cm below the right costal margin. Laboratory studies show:
Hemoglobin 17 g/dl
Reticulocyte count 0.5 %
Total bilirubin 21.2 mg/dl
Direct bilirubin 2 mg/dl
Indirect bilirubin 19.1 mg/dl
Coombs test Negative
Which of the following is the most appropriate next step in management?
A. Replace breast feeding with formula feeds
B. MRI of the brain
C. Phototherapy (Correct Answer)
D. Increase frequency of breast feeds
E. Intravenous immunoglobulin
Explanation: ***Phototherapy***
- The neonate has significantly elevated **indirect bilirubin** (19.1 mg/dL) at 4 days of age, which, along with risk factors like the older sibling's jaundice and vacuum-assisted delivery, places him at high risk for **kernicterus**. Phototherapy is the primary treatment to reduce bilirubin levels.
- The combination of **jaundice, high indirect bilirubin, normal reticulocyte count, and negative Coombs test** suggests exaggerated physiologic jaundice or possibly breastfeeding jaundice, warranting intervention at this level.
*Replace breast feeding with formula feeds*
- While temporary cessation of breastfeeding can lower bilirubin in some cases of **breast milk jaundice**, it is not the first-line treatment, especially given the high bilirubin level.
- Discontinuing breastfeeding can interfere with successful long-term breastfeeding. This option is usually considered after phototherapy has failed or in conjunction with it if bilirubin levels remain stubbornly high.
*MRI of the brain*
- An MRI of the brain is indicated to assess for **kernicterus** if there are neurological signs, but the neonate appears alert and comfortable, and there are no signs of acute bilirubin encephalopathy.
- The immediate priority is to lower the bilirubin level to prevent neurological damage, rather than evaluate for damage that may not yet be present.
*Increase frequency of breast feeds*
- This intervention is appropriate for **breastfeeding failure jaundice** (early onset jaundice related to inadequate milk intake), which typically presents earlier and with signs of dehydration or poor feeding.
- While increasing feeding frequency is generally beneficial, the high bilirubin level in this case requires more aggressive intervention like phototherapy.
*Intravenous immunoglobulin*
- **Intravenous immunoglobulin (IVIG)** is indicated for severe hyperbilirubinemia, especially when due to **isoimmune hemolytic disease** (e.g., ABO or Rh incompatibility), which is ruled out by the negative Coombs test.
- There is no evidence of hemolytic disease, making IVIG an inappropriate treatment in this scenario.
Question 67: A neonate born at 33 weeks is transferred to the NICU after a complicated pregnancy and C-section. A week after being admitted, he developed a fever and became lethargic and minimally responsive to stimuli. A lumbar puncture is performed that reveals the following:
Appearance Cloudy
Protein 64 mg/dL
Glucose 22 mg/dL
Pressure 330 mm H20
Cells 295 cells/mm³ (> 90% PMN)
A specimen is sent to microbiology and reveals gram-negative rods. Which of the following is the next appropriate step in management?
A. MRI scan of the head
B. Start the patient on IV ceftriaxone
C. Provide supportive measures only
D. Start the patient on IV cefotaxime (Correct Answer)
E. Start the patient on oral rifampin
Explanation: ***Start the patient on IV cefotaxime***
- The cerebrospinal fluid (CSF) analysis with **cloudy appearance, elevated protein, low glucose, high pressure, and predominant PMNs**, coupled with **gram-negative rods** on microscopy, is highly suggestive of **bacterial meningitis** in a neonate.
- **Cefotaxime** is a third-generation cephalosporin commonly used for neonatal meningitis caused by gram-negative organisms due to its excellent CSF penetration and broad-spectrum activity, particularly against common neonatal pathogens like *E. coli* which can present as gram-negative rods.
*MRI scan of the head*
- An MRI would be considered **after initiating appropriate antibiotic treatment** to assess for complications like abscess formation or ventriculitis, not as the immediate next step in an acute, life-threatening infection.
- Delaying antibiotic treatment for imaging in acute bacterial meningitis can lead to increased morbidity and mortality.
*Start the patient on IV ceftriaxone*
- While ceftriaxone is a third-generation cephalosporin, it is **generally avoided in neonates** due to the risk of **biliary sludging** and **kernicterus**.
- Ceftriaxone competes with bilirubin for albumin binding sites, which is particularly risky in neonates who are already prone to hyperbilirubinemia.
*Provide supportive measures only*
- Given the strong evidence of **bacterial meningitis**, providing only supportive measures without specific antibiotic treatment would be inadequate and would lead to rapid deterioration and potentially fatal outcomes.
- Bacterial meningitis requires prompt and aggressive antimicrobial therapy.
*Start the patient on oral rifampin*
- **Rifampin is never used as monotherapy for bacterial meningitis** due to rapid resistance development and its primary role is in specific infections like tuberculosis or as part of combination therapy for certain resistant bacteria.
- Oral administration is also not ideal for acutely ill neonates with meningitis needing rapid, high-concentration antibiotics in the CSF.
Question 68: A 2-week-old female newborn is brought to the physician for the evaluation of red eyes with discharge for 2 days. She was born at 39 weeks' gestation to a 22-year-old woman. Pregnancy and delivery were uncomplicated. The mother received irregular prenatal care during the second half of the pregnancy. The newborn weighed 3700 g (8 lb 2.5 oz) at birth, and no congenital anomalies were noted. She currently weighs 4000 g (8 lb 13 oz). Examination of the newborn shows pink skin. The lungs are clear to auscultation. There is mucopurulent discharge in both eyes and mild eyelid swelling. Polymerase chain reaction assay of conjunctival scraping confirms the diagnosis. Which of the following is the most appropriate next step in management?
A. Oral doxycycline administration
B. Reassurance and follow-up in 1 week
C. Oral erythromycin administration (Correct Answer)
D. Intravenous acyclovir administration
E. Topical silver nitrate administration
Explanation: ***Oral erythromycin administration***
- This presentation describes **ophthalmia neonatorum** caused by *Chlamydia trachomatis *, which typically presents with **mucopurulent discharge** and eyelid swelling in newborns aged 5-14 days.
- **Oral erythromycin** is the recommended treatment for **chlamydial conjunctivitis** in neonates because it treats both ocular and potential systemic infections (e.g., pneumonitis).
*Oral doxycycline administration*
- **Doxycycline** is an antibiotic used for chlamydial infections in adults but is **contraindicated in children** under 8 years of age due to the risk of **dental staining** and inhibition of bone growth.
- Therefore, it is not an appropriate treatment for a 2-week-old infant.
*Reassurance and follow-up in 1 week*
- **Chlamydial conjunctivitis** can lead to serious complications if left untreated, including **corneal scarring** and **pneumonia**.
- Therefore, prompt treatment with appropriate antibiotics is necessary, and reassurance alone is insufficient.
*Intravenous acyclovir administration*
- **Acyclovir** is an antiviral medication used to treat herpes simplex virus (HSV) infections.
- While **herpes simplex ophthalmia neonatorum** can cause similar symptoms, the PCR assay confirming *Chlamydia trachomatis* rules out HSV as the cause.
*Topical silver nitrate administration*
- **Topical silver nitrate** was historically used for **gonococcal ophthalmia prophylaxis**, but it is no longer the preferred prophylactic agent and is **ineffective against *Chlamydia***.
- Additionally, it can cause **chemical conjunctivitis** and would not treat an established chlamydial infection.
Question 69: A 6-day-old male newborn is brought to the physician by his mother for the evaluation of yellowing of his skin and eyes for one day. The mother reports that she is breastfeeding her son about 7 times per day. She also states that her son had two wet diapers and two bowel movements yesterday. He was born at 38 weeks' gestation and weighed 3500 g (7.7 lb); he currently weighs 3000 g (6.6 lb). His newborn screening was normal. His temperature is 37°C (98.6°F), pulse is 180/min, and blood pressure is 75/45 mm Hg. Physical examination shows scleral icterus, widespread jaundice, and dry mucous membranes. The remainder of the examination shows no abnormalities. Serum studies show:
Bilirubin
Total 9 mg/dL
Direct 0.7 mg/dL
AST 15 U/L
ALT 15 U/L
Which of the following is the most appropriate next step in the management of this patient?
A. Phototherapy
B. Intravenous immunoglobulin
C. Abdominal sonography
D. Phenobarbital
E. Increasing frequency of breastfeeding (Correct Answer)
Explanation: ***Increasing frequency of breastfeeding***
- The infant's **weight loss** of 14% (from 3500g to 3000g) and signs of **dehydration** (dry mucous membranes) suggest **insufficient milk intake**, contributing to **breastfeeding jaundice**.
- Increasing feeding frequency will improve hydration and milk intake, stimulating bowel movements and **excreting bilirubin** more effectively, thereby resolving the jaundice.
*Phototherapy*
- While phototherapy is used to treat hyperbilirubinemia, the total bilirubin level of 9 mg/dL in this 6-day-old infant is **below the threshold** typically requiring phototherapy, especially since the indirect bilirubin is 8.3 mg/dL.
- The primary issue here is inadequate feeding, and addressing that is the most appropriate first step before considering more invasive treatments.
*Intravenous immunoglobulin*
- **IVIG** is indicated for severe **alloimmune hemolytic disease** when bilirubin levels are rapidly rising and approaching exchange transfusion thresholds despite intensive phototherapy.
- There is no evidence of hemolytic disease (e.g., ABO or Rh incompatibility) in this case, and the bilirubin level is not critically high.
*Abdominal sonography*
- **Abdominal sonography** is used to investigate causes of **cholestatic jaundice** (elevated direct bilirubin), such as biliary atresia or choledochal cyst.
- In this patient, the **direct bilirubin is normal (0.7 mg/dL)**, indicating unconjugated hyperbilirubinemia, so abdominal sonography is not appropriate at this time.
*Phenobarbital*
- **Phenobarbital** is an enzyme inducer that can increase the conjugation and excretion of bilirubin by the liver.
- Its use is generally reserved for severe or refractory cases of hyperbilirubinemia, such as in **Crigler-Najjar syndrome** or when phototherapy fails, and it is not a first-line treatment for breastfeeding jaundice.
Question 70: Three weeks after birth, an infant girl develops episodes of apnea. She has become increasingly lethargic over the past two days, and experienced two episodes of apnea lasting 10 seconds each within the last day. She was born at 31 weeks of gestation and weighed 1600-g (3-lb 8-oz). Apgar scores were 4 and 7 at 1 and 5 minutes, respectively. She takes no medications. Her temperature is 36.7°C (98.0°F), pulse is 185/min, respirations are 60/min and irregular, and blood pressure is 70/35 mm Hg. She appears pale. Physical examination shows no abnormalities. Laboratory studies show a hemoglobin of 6.5 g/dL, a reticulocyte count of 0.5%, and a mean corpuscular volume of 92 μm3. Leukocyte count, platelet count, total bilirubin and indirect bilirubin are all within reference range. Which of the following is the most likely underlying mechanism of this patient's anemia?
A. Defective δ-aminolevulinic acid synthase
B. Glucose-6-phosphate dehydrogenase deficiency
C. Bone marrow suppression
D. Impaired erythropoietin production (Correct Answer)
E. Iron deficiency
Explanation: ***Impaired erythropoietin production***
- This infant is a **premature neonate** (born at 31 weeks gestation) with **anemia** (Hb 6.5 g/dL) and a **low reticulocyte count (0.5%)**, indicating **underproduction of red blood cells**.
- **Prematurity** often leads to an inadequate erythropoietin response to anemia, as the kidneys, which produce erythropoietin, are still immature.
*Defective δ-aminolevulinic acid synthase*
- This enzyme defect causes **sideroblastic anemia**, characterized by **microcytic hypochromic red blood cells** and **ring sideroblasts** in the bone marrow.
- The patient's **normocytic anemia** (MCV 92 μm3) and the absence of specific risk factors for sideroblastic anemia make this diagnosis unlikely.
*Glucose-6-phosphate dehydrogenase deficiency*
- This condition causes **hemolytic anemia** due to oxidative stress, typically presenting with **jaundice**, **dark urine**, and a **reticulocytosis** due to increased red blood cell destruction.
- The patient's normal bilirubin levels, lack of jaundice, and low reticulocyte count rule out hemolytic processes.
*Bone marrow suppression*
- While bone marrow suppression can cause anemia with a low reticulocyte count, there are **no signs of infection**, **medication exposure**, or **other systemic illness** that would typically cause generalized bone marrow suppression in this infant.
- The specific context of prematurity points more strongly towards erythropoietin deficiency as the primary cause.
*Iron deficiency*
- Iron deficiency anemia typically presents as **microcytic anemia** (low MCV), whereas this patient has a **normocytic anemia** (MCV 92 μm3).
- Although common in premature infants, the MCV does not support iron deficiency as the primary cause of this specific presentation.
