Diagnosis and Management of Vesicular Lesions in Children

Etiology and Clinical Presentation

The Centers for Disease Control and Prevention (CDC) recommends considering herpes simplex virus (HSV) infection in children with vesicular lesions, particularly in immunocompetent toddlers outside the neonatal period 1, 2
HSV can present with vesicular lesions in the diaper/buttock area, and clinical diagnosis is based on the typical appearance of vesicles and ulcers, though viral culture or PCR from vesicular fluid provides definitive diagnosis 1, 2
In a 20-month-old, HSV infection would most commonly represent primary infection rather than reactivation, which carries higher risk for severe manifestations 3, 4
The American Academy of Pediatrics (AAP) notes that varicella typically presents with a generalized vesicular rash that includes the trunk and buttocks, with lesions in various stages of development 4, 5
Fever and systemic symptoms typically accompany the rash in varicella 4

The CDC recommends obtaining cultures from skin vesicles for suspected HSV infection in children, and viral culture or PCR from vesicular fluid is the gold standard for HSV diagnosis 1, 2
The AAP suggests that timing and progression of lesions, exposure history, associated symptoms, immunization status, and immune status are important elements to elicit in the history 1, 4
Physical examination findings, including distribution pattern and lesion characteristics, can help differentiate between HSV, varicella, and other etiologies 1, 4

The CDC recommends empiric acyclovir for any immunocompromised child with vesicular lesions while awaiting diagnostic confirmation, and oral acyclovir 20 mg/kg/dose three times daily for 7-14 days is appropriate for localized mucocutaneous HSV in immunocompetent children 1, 2
The AAP notes that most enteroviral infections and varicella in healthy children require only supportive care, including antihistamines for pruritus and maintaining skin hygiene to prevent secondary bacterial infection 4, 5

The CDC recommends immediate evaluation for disseminated HSV if fever, irritability, or systemic symptoms are present in conjunction with vesicular lesions, and any concern for HSV encephalitis requires immediate IV acyclovir 1, 2
HIV-infected or immunocompromised children can develop severe local lesions or disseminated HSV with visceral involvement, and a lower threshold for hospitalization and IV acyclovir is recommended in this population 1, 2, 3

The Centers for Disease Control and Prevention recommends acyclovir as the drug of choice for all HSV infections in pediatric patients, with dosing and duration determined by disease severity and anatomic location 6
For CNS or disseminated disease in neonates, administer IV acyclovir 20 mg/kg/dose three times daily for 21 days, and do not discontinue therapy until repeat CSF HSV DNA PCR is negative at day 19-21 of treatment 6, 7
For skin, eye, and mouth disease in neonates, administer IV acyclovir 20 mg/kg/dose three times daily for 14 days, and monitor for cutaneous recurrences during the first 6 months after treatment 6, 8
The American Academy of Pediatrics recommends obtaining cultures from multiple sites, including blood, skin vesicles, mouth/nasopharynx, eyes, urine, and stool/rectum, for suspected neonatal HSV 6, 7

For HIV-infected children with symptomatic gingivostomatitis, the Centers for Disease Control and Prevention recommends IV acyclovir 5-10 mg/kg/dose three times daily for 7-14 days, or oral acyclovir 20 mg/kg/dose three times daily for 7-14 days 6, 7, 8
For immunocompromised children, episodes of HSV are usually longer and more severe, potentially involving the entire oral cavity or extending across the face 9

The Centers for Disease Control and Prevention recommends monitoring for neutropenia, phlebitis, renal toxicity, nausea, vomiting, and rash in patients receiving acyclovir 6, 7
Dose adjustment is required based on creatinine clearance in patients with renal insufficiency or failure 6, 7

The Centers for Disease Control and Prevention recommends avoiding kissing or direct facial contact with toddlers until complete crusting of lesions, typically 4-7 days after rash onset 10
HSV-1 can be transmitted even without visible cold sores through asymptomatic viral shedding 10