A 2-day-old boy is evaluated in the newborn nursery due to a diffuse rash that developed this morning on his torso and extremities. The patient has been breastfeeding every 2-3 hours and voiding frequently. He was born via vaginal delivery at 40 weeks gestation to a 30-year-old woman. Maternal history is notable for the occasional development of cold sores during stressful events, most recently a year ago. Temperature is 36.7 C (98.1 F), pulse is 132/min, and respirations are 42/min. Physical examination shows pustules overlying erythematous skin on the extremities; the palms and soles are spared. There are scattered erythematous papules, as shown in the exhibit. Examination is otherwise unremarkable. Which of the following is the most appropriate next step in management of this patient?

Question

A 2-day-old boy is evaluated in the newborn nursery due to a diffuse rash that developed this morning on his torso and extremities.  The patient has been breastfeeding every 2-3 hours and voiding frequently.  He was born via vaginal delivery at 40 weeks gestation to a 30-year-old woman.  Maternal history is notable for the occasional development of cold sores during stressful events, most recently a year ago.  Temperature is 36.7 C (98.1 F), pulse is 132/min, and respirations are 42/min.  Physical examination shows pustules overlying erythematous skin on the extremities; the palms and soles are spared.  There are scattered erythematous papules, as shown in the exhibit.  Examination is otherwise unremarkable.  Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d644_4dad_bc81_6f9909381e00_MD0003_00 Scattered erythematous papules and pustules in a well-appearing child in the first week of life are suggestive of erythema toxicum neonatorum (ETN), a benign and transient rash common in newborns. The etiology is unclear but may be due to innate immune response to skin bacteria penetrating hair follicles. ETN typically presents by age 3 days in full-term neonates. The rash usually begins as small, poorly demarcated erythematous macules and papules that classically involve the trunk and proximal extremities but may occur anywhere except the palms and soles (where no hair follicles are present). Lesions often evolve into small, firm pustules on erythematous bases. The rash is asymptomatic, and infants are otherwise well-appearing. Features that should raise suspicion of an alternate diagnosis include involvement of the palms and soles, lesions with crusting or a vesicular appearance, and systemic symptoms (eg, fever, irritability). ETN is a clinical diagnosis and requires no treatment. Atypical cases may rarely require evaluation of the pustule contents, which are sterile with an eosinophilic infiltration. The rash may wax and wane in severity, but reassurance should be provided because it resolves spontaneously in a week. (Choice A) Congenital syphilis, which is treated with intravenous penicillin, can present with a maculopapular rash distributed over the torso and extremities. However, the rash typically lacks pustules, involves the soles, and is accompanied by rhinitis (snuffles), hepatomegaly, and lymphadenopathy, features not seen in this patient. (Choice B) Intravenous valacyclovir is used to treat neonatal herpes, which presents as clustered vesicles on erythematous bases, findings not seen in this patient. erythematous bases (Choice D) Low-potency topical corticosteroids can be considered for severe miliaria rubra (heat rash), which presents as a fine, erythematous papular rash. Scattered pustules, as described in this patient, would not be present. erythematous papular rash (Choice E) Topical mupirocin treats staphylococcal pustulosis, which presents in neonates as localized erythematous pustules, vesicles, or bullous lesions that rupture to form erosions and honey-colored crusts. These features are absent in this patient. Moreover, the classic distribution involves the diaper area or a prior wound (eg, circumcision site). Educational objective: Erythema toxicum neonatorum is a benign neonatal rash that presents within the first 3 days of life as erythematous macules, papules, or pustules on the trunk and proximal extremities, sparing the palms and soles. Patients are otherwise asymptomatic, no treatment is required, and the rash self-resolves within a week. References: Newborn skin: part I. Common rashes. (http://www.ncbi.nlm.nih.gov/pubmed/18236822)

A 2-Day-Old Boy Is Evaluated in the Newborn Nursery Due