Chickenpox

Diagnosis: Chickenpox

Vesicular eruption on the trunk demonstrating papules, vesicles, and crusts.

Clinical Presentation

Vesicular eruption on the trunk demonstrating papules, vesicles, and crusts.

Clinical History

Submitted by Alaa Saad. Originally posted September 12, 2010.

Treatment

See case discussion.

Differential Diagnosis

• Smallpox • Disseminated herpes simplex • Hand, foot, and mouth disease • Insect bites • Impetigo • Scabies • Drug eruption

Key Learnings

• Caused by Varicella-Zoster Virus (VZV) — primary infection • Classic: lesions in different stages simultaneously ("crops") — "dew drop on a rose petal" • Centripetal distribution (trunk > extremities) — opposite of smallpox (centrifugal) • Highly contagious (airborne + contact) — R0 ~10-12 • Contagious from 2 days before rash until all lesions crusted • Complications: secondary bacterial infection, pneumonia (especially adults), encephalitis • Immunocompromised: disseminated, hemorrhagic, potentially fatal — IV acyclovir • VZV remains latent in dorsal root ganglia → reactivation as herpes zoster

Tags: chickenpox, alaa saad