PASS Syndrome: An IL-1-Driven Autoinflammatory Disease

Area of Science:

• Immunology
• Dermatology
• Rheumatology

Background:

• PASS syndrome is a rare autoinflammatory disorder featuring pyoderma gangrenosum, acne vulgaris, hidradenitis suppurativa, and ankylosing spondylitis.
• The condition is characterized by a chronic-relapsing inflammatory course.

Observation:

• A case of PASS syndrome is presented with recurrent purulent skin lesions and seronegative spondylarthritis.
• Disease exacerbation included fever and elevated Interleukin-1 beta (IL-1β) serum levels.
• Skin lesions exhibited sterile neutrophilic infiltrates.

Findings:

• The patient's skin lesions responded rapidly to anakinra, an IL-1 receptor antagonist.
• Genetic analysis did not reveal mutations in PSTPIP1, unlike in PAPA and PAPASH syndromes.
• This suggests potential involvement of other specific mutations within the IL-1 pathway.

Implications:

• This case underscores the autoinflammatory nature of PASS syndrome and the therapeutic potential of IL-1 blockade.
• The findings suggest that genetic defects beyond PSTPIP1 may underlie PASS syndrome, potentially involving other components of the IL-1 signaling pathway.
• Further research into the IL-1 pathway is warranted for a comprehensive understanding and improved management of PASS syndrome.