Skin-Eye-Mouth Disease in Newborns: Clinical Appearance
Skin-eye-mouth (SEM) disease in newborns refers to neonatal herpes simplex virus infection and classically presents with vesicular skin lesions, eye involvement (conjunctivitis), and oral mucosal erosions or ulcerations, though less than half of affected neonates show the characteristic vesicular rash at initial presentation.
Key Clinical Features
Skin Manifestations
- Vesicular lesions are the classic finding, but they appear in less than 50% of cases initially 1
- Lesions can present in atypical patterns, including zosteriform (dermatomal) distributions 2
- Some infants may have only localized skin findings without the typical widespread vesicles
- The absence of vesicles does NOT rule out HSV infection—this is a critical pitfall
Eye Involvement
When present, ocular manifestations include:
- Conjunctivitis with discharge (may be purulent or mucopurulent)
- Eyelid edema
- Bulbar conjunctival injection
- Keratitis (corneal involvement) can develop and lead to scarring 3
Mouth/Mucosal Findings
- Oral mucosal erosions or ulcerations 4
- These may be painful and affect feeding
- Mucosal involvement can occur with or without skin lesions
Timing and Presentation Patterns
Most infants present within the first 28 days of life (88% by day 28), with a significant subset presenting between days 2-4 of life 1. The classic triad of skin-eye-mouth findings represents only 20% of neonatal HSV cases 1.
Important Clinical Context
84% of neonatal HSV cases present with at least one of three cardinal features: seizures, vesicular rash, or critical illness requiring intensive care 1. However, 16% have nonspecific presentations without these classic signs—these infants are typically:
- ≤14 days old
- Have cerebrospinal fluid pleocytosis
- Develop more specific signs within 24 hours 1
Critical Pitfalls to Avoid
- Do not wait for vesicles to appear before considering HSV—many cases lack this finding initially
- Do not assume absence of maternal HSV history excludes the diagnosis—only 20% of cases have documented maternal infection history 5
- Recognize that SEM disease can progress to disseminated or CNS disease if untreated, with significant mortality and morbidity 6, 4
Prognosis
SEM disease has no mortality when treated appropriately with antiviral therapy 6, making early recognition crucial. Without treatment, there is substantial risk of progression to life-threatening disseminated or central nervous system disease 2, 4.
The key to diagnosis is maintaining high clinical suspicion in any neonate presenting with vesicular lesions, unexplained conjunctivitis, oral ulcerations, or nonspecific illness in the first month of life—particularly in the first two weeks—even without the complete triad of skin-eye-mouth involvement.