Leukocyte Adhesion Deficiency-I Caused by a Novel Mutation in ITGB2 Presenting with Pyoderma Gangrenosum

Background: Leukocyte adhesion deficiency (LAD) syndromes are primary immunodeficiency disorders caused by defects in adhesion molecules on leukocytes resulting in impaired migration into tissues. Common cutaneous manifestations of LAD include bacterial infections, omphalitis with delayed separation of the umbilical cord, impaired pus formation and poor wound healing. LAD is associated with significant morbidity and mortality, making early diagnosis and management integral in the care of these patients. Methods: Molecular testing and flow cytometry for expression of CD18 were performed on 2 siblings presenting with cutaneous lesions including pyoderma gangrenosum (PG). Results: We describe 2 siblings with a novel homozygous mutation in ITGB2 (c.2070del, p.Asp690Glufs*25) resulting in an atypical presentation of LAD-I with PG. Conclusion: LAD should be considered in patients presenting with unexplained PG, even in the absence of significant infections or umbilical cord complications. Statement of novelty: To the best of our knowledge, we describe a novel homozygous mutation in ITGB2 (c.2070del, p.Asp690Glufs*25) resulting in LAD-I. Patients with LAD-I may present with unexplained PG and may lack classic symptoms including umbilical cord complications.