Accentuated varicella exanthems due to cast application

Area of Science:

• Dermatology
• Viral Infections
• Pediatrics

Background:

• Varicella zoster virus (VZV) causes chickenpox, a common childhood illness characterized by a widespread itchy rash.
• The typical VZV exanthem distribution is generalized, affecting the trunk and extremities.
• Factors influencing localized VZV reactivation or exacerbation are not fully understood.

Observation:

• A 14-year-old male presented with varicella zoster exanthems.
• Cast application was performed on the left forearm.
• VZV lesions predominantly appeared on the left forearm under the cast and on the trunk, with rare lesions elsewhere.

Findings:

• Localized augmentation of varicella zoster exanthems was observed under a cast.
• The pressure and heat generated by the cast are hypothesized to be the cause of increased lesion development in that specific area.
• This suggests a potential role for localized environmental factors in modulating VZV exanthem expression.

Implications:

• This case suggests that localized pressure and heat may exacerbate or induce varicella zoster lesions.
• Understanding these localized factors could inform management strategies for VZV infections, particularly in immobilized patients.
• Further research is warranted to explore the mechanisms behind localized VZV exanthem augmentation.