Speediatrics: Can you solve this quick case of a child’s rash?

Clinical Features:

• Presentation:
  • Acute onset of painful, monomorphic vesicles or punched-out erosions.
  • Lesions typically appear in clusters and can coalesce.
• Symptoms:
  • Fever and malaise often accompany skin symptoms.
  • Regional lymphadenopathy may be present.
  • Pruritus can be severe but is often overshadowed by pain.
• Affected Areas:
  • Commonly affects the face, neck, and upper trunk.
  • Pre-existing areas of eczema are most susceptible.

Epidemiology:

• Age Group:
  • Most commonly affects infants and young children.
  • Peak incidence in children aged 6 months to 3 years.
• Underlying Condition:
  • Almost always occurs in individuals with pre-existing atopic dermatitis (eczema).

Diagnosis:

• Clinical Evaluation:
  • Detailed patient history, focusing on rapid progression of vesicular lesions.
  • Physical examination highlighting characteristic lesions.
• Laboratory Tests:
  • Viral cultures or PCR: Confirm herpes simplex virus (HSV) infection.
  • Blood tests: Full blood count and liver function tests if systemic involvement is suspected (in secondary care)

Differential Diagnosis:

• Impetigo:
  • Typically honey-colored crusts rather than vesicular lesions, and well child.
  • Caused by Staphylococcus aureus or Streptococcus pyogenes.
• Varicella (Chickenpox):
  • Polymorphic rash (vesicles, pustules, and crusts in various stages).
  • History of exposure or prodromal symptoms (fever, malaise).
• Contact Dermatitis:
  • Erythematous, weepy lesions; history of contact with irritants/allergens.
  • Itching more prominent than pain.
• Scabies:
  • Intensely pruritic rash with burrows; often spares the face.
  • History of close contact with an infected individual.

Red Flags:

• Systemic Symptoms:
  • High fever, malaise, lethargy indicating potential systemic involvement.
  • Any signs of disseminated infection.
• Ocular Involvement:
  • Herpetic lesions near the eyes or visual disturbances necessitate immediate ophthalmological referral.
• Immunocompromised State:
  • Increased risk of severe and disseminated infection.
• Rapid Progression:
  • Quick spread of lesions or development of necrosis signals need for urgent intervention.

Management:

• Most cases will need urgent paediatric review
• Antiviral Therapy:
  • Oral acyclovir.
  • IV acyclovir: For severe or systemic cases.
• Adjunctive Treatments:
  • Topical antibiotics: To prevent secondary bacterial infection.
  • Pain management: Analgesics for symptomatic relief.
• Hydration and Skin Care:
  • Emollients: Maintain skin barrier function.
  • Avoidance of irritants: Minimize exacerbation of underlying eczema.

Patient Education:

• Understanding Eczema Herpeticum:
  • Provide information on the nature of the infection and its relationship with eczema.
• Prevention:
  • Stress the importance of managing eczema flare-ups to reduce the risk of developing eczema herpeticum.
  • Discuss the potential need for antiviral prophylaxis in recurrent cases.
• When to Seek Help:
  • Educate about recognizing red flags and seeking timely medical attention.