Maternity ward staff request a pediatric evaluation for an infant who has developed a new … — USMLE Step 2 CK

Maternity ward staff request a pediatric evaluation for an infant who has developed a new skin eruption. The infant was delivered vaginally two days ago at $39$ weeks gestation to a $26$ -year-old primigravida. The mother has a history of recurrent genital herpes simplex virus (HSV) infections but had no active lesions or prodromal symptoms at the time of delivery. She received daily valacyclovir prophylaxis throughout the third trimester. Currently, the infant is afebrile, breastfeeding vigorously every $2$ to $3$ hours, and has age-appropriate wet diapers and stools. Physical examination reveals multiple scattered erythematous patches with $1$ - to $2$ -mm central yellowish pustules distributed widely over the chest, abdomen, and back. The palms and soles are completely spared. The infant has normal tone, an intact Moro reflex, and no hepatosplenomegaly. Which of the following is the most appropriate next step in the management of this patient?

Reassure the parents and continue routine newborn careCevap
B
Obtain surface viral swabs and immediately begin intravenous acyclovir
C
Perform a lumbar puncture, draw blood cultures, and administer intravenous ampicillin and gentamicin
D
Obtain a complete blood count and administer intramuscular ceftriaxone
E
Scrape a pustular lesion for Gram stain and prescribe topical mupirocin

Cevap

Reassure the parents and continue routine newborn care.

The correct answer involves reassuring the parents, as this infant is presenting with Erythema Toxicum Neonatorum (ETN). ETN is a benign, self-limited condition that occurs in up to

50\%

of full-term neonates, typically appearing on days

2

3

of life. It is characterized by scattered erythematous macules with central

1

- to

2

-mm yellowish-white pustules, most prominently on the trunk and proximal extremities, while classically sparing the palms and soles. Because the infant is afebrile, feeding vigorously, and well-appearing, infectious etiologies are highly unlikely. A Wright or Giemsa stain of the pustules (if performed) would show numerous eosinophils, confirming the diagnosis, but clinical diagnosis is sufficient and no treatment other than reassurance is indicated.

Adım Adım Çözüm

Evaluate the morphological characteristics of the neonatal rash.

The rash consists of erythematous patches with small central yellowish pustules, sparing the palms and soles.

Identifying the specific appearance of the rash is essential to distinguish between benign newborn eruptions and infectious etiologies.

Assess the clinical status of the neonate and maternal risk factors.

The infant is vigorous, afebrile, and feeding well. The mother has a history of HSV but was on prophylaxis without active lesions at delivery.

A well-appearing infant drastically lowers the suspicion for systemic infectious processes like early-onset sepsis or disseminated HSV.

Synthesize the findings to determine the correct diagnosis and management.

The clinical picture is diagnostic for Erythema Toxicum Neonatorum (ETN), necessitating no intervention.

ETN is a common, benign, self-limited condition that requires only reassurance.

Anahtar Kavram

Erythema toxicum neonatorum (ETN) is a benign, self-limited neonatal rash characterized by erythematous macules with central pustules that requires only reassurance, and must be distinguished from infectious rashes.

Soru

Cevap

Adım Adım Çözüm

Anahtar Kavram

Sık Yapılan Hatalar

Konular

Bu konudan daha fazla soru