Still disease with persistent atypical dermatomyositis-like skin eruption: two cases associated with macrophage...

Area of Science:

• Rheumatology
• Dermatology
• Immunology

Background:

• Still disease, a rare inflammatory condition, typically features a transient salmon-colored rash coinciding with fever spikes.
• Atypical, persistent, pruritic eruptions (PPEs) with distinct clinical and histological features are recognized but not part of diagnostic criteria.
• Some PPEs, like periorbital erythema and flagellate papules, mimic cutaneous dermatomyositis (DM).

Observation:

• This report details two cases of Still disease exhibiting atypical, dermatomyositis-like eruptions.
• One case involved a pediatric patient, a demographic rarely documented with this presentation.
• The second case involved an adult patient.

Findings:

• Both patients presented with persistent, pruritic, polymorphic skin lesions suggestive of DM.
• Both patients developed secondary macrophage activation syndrome (MAS).
• The presence of these DM-like lesions in adult-onset Still disease is associated with poorer prognosis and increased mortality.

Implications:

• Recognizing these atypical DM-like rashes in Still disease is crucial for early diagnosis and management.
• The association with MAS highlights the potential severity of these persistent cutaneous manifestations.
• Further research is needed to understand the pathogenesis and prognostic significance of these rare eruptions in pediatric and adult Still disease.