Poster Display Autoinflammation

RARE SKIN LESIONS IN A BOY WITH ACTIVATED PHOSPHOINOSITIDE 3-KINASE DELTA SYNDROME

Lecture Time
10:01 - 10:02
Presenter
  • Delfien J. Bogaert, Belgium
Room
Poster Area
Date
19.09.2019, Thursday
Session Time
10:00 - 17:00
Board Number
1
Presentation Topic
Autoinflammation

Abstract

Background and Aims

Activated phosphoinositide 3-kinase delta (PI3K) syndrome (APDS) is characterized by variable humoral and cellular defects, recurrent infections, lymphoma, autoimmune features, and growth and developmental delay.

Sweet syndrome, or acute febrile neutrophilic dermatosis, is a rare inflammatory skin condition. About half of cases have an underlying systemic disorder, mainly malignancies and autoinflammatory conditions. It has only been sporadically reported in patients with immunodeficiency.

We report a boy with APDS presenting as a combined immunodeficiency and Sweet syndrome.

Methods

Immunological tests, skin biopsies and PID gene panel analysis were performed.

Results

A boy, currently 16 years old, suffered from recurrent bacterial infections since the age of 3 years. He also developed bronchiectasis, lymphadenopathies and splenomegaly. Immunological work-up revealed low IgG2, reduced polysaccharide antibody responses, monocytopenia and T, B and NK lymphopenia. Recently, we identified a PIK3CD mutation causing APDS.

Remarkably, since 5 years of age, he had recurrent painful erythematous nodules and plaques on his limbs and abdomen, accompanied by fever and elevated inflammatory markers. Biopsies showed a dense neutrophilic infiltrate confirming the diagnosis of Sweet syndrome. Acute episodes responded well to systemic corticosteroids. Up till now, he requires dapsone maintenance therapy to prevent relapse.

Conclusions

To our knowledge, this is the first report of an APDS patient with Sweet syndrome. The pathophysiology of Sweet syndrome is unclear but involves activation of innate inflammatory signaling. Previous studies have demonstrated a role for PI3K/Akt signaling in NLRP3-inflammasome activation. Together, this suggests dysregulation of inflammasome activation in APDS patients, implying potentially therapeutic effects of IL-1 inhibition.

Hide