Case Presentation: A 4-day old male was born full term at an outside hospital to a mother with a new vesicular labial lesion found during vaginal delivery. A viral culture of the lesion and maternal Herpes Simplex Virus (HSV) serology were obtained, but the patient did not undergo further work up or treatment in the nursery. Post-discharge, the culture was positive for HSV-2 with positive HSV-2 IgG, and therefore the patient was referred to the emergency department. He was well-appearing, afebrile, and hemodynamically stable. His physical examination and initial laboratory studies were unremarkable with a normal leukocyte count, mildly elevated procalcitonin (0.31 ng/mL), and normal glucose (63 mg/dL). Further workup including lumbar puncture was performed and he was admitted for empiric acyclovir therapy. Initial CSF studies were unremarkable with a negative meningitis filmarray PCR panel. After 12 hours of admission, due to the patient’s clinical stability, reassuring laboratory findings, and likelihood that the herpes lesion was due to reactivation based on further history and maternal HSV IgG antibodies, the patient was discharged with close outpatient follow up. Post-discharge, CSF, skin, and blood cultures all resulted negative.
Discussion: Neonatal HSV can be transmitted via ascending infection or at birth via contact with active lesions. There is a 25-60% risk of transmission in the setting of a primary lesion compared to 2% with reactivation. Neonatal HSV can present any time from birth to 6 weeks and may present with localized, disseminated, or central nervous system involvement. This case underscores how paramount it is for pediatric hospitalists to discern when a proactive and decisive intervention is needed for optimal patient outcomes and highlights the controversy regarding management of an asymptomatic neonate with HSV exposure. Careful attention should be given to guidelines for management of these neonates based on whether the infection is likely primary, secondary, or unknown. Guidelines advise the extent of work-up required and when to begin empiric therapy, however, they do not address re-admission of otherwise well infants who failed to be worked up in the nursery. When considering re-admission of these patients, it is imperative to weigh risks of undiagnosed neonatal HSV against unnecessary testing and hospitalization. There have been efforts to identify predictors of disease severity and develop an HSV risk score, which may prevent unnecessary hospitalizations and minimize health care cost.
Conclusions: This case addresses the situation in which a newborn fails to be treated per established guidelines in the nursery and highlights the need for thorough discussion regarding work up and hospitalization when the patient later presents asymptomatically. In the nursery, adherence to guidelines when there is concern for infection is crucial to prevent unnecessary future interventions. Upon re-evaluation of the asymptomatic newborn, guidance from and further research into developing HSV risk scores and determining their efficacy may be pivotal in determining the need for re-admission.