Leukocyte adhesion deficiency is caused by a defect in CD18-containing integrins, which impairs leukocyte adhesion and endothelial transmigration. This results in recurrent skin and mucosal infections without pus formation, impaired wound healing, and delayed umbilical cord separation beyond 3 weeks of age. Laboratory findings include leukocytosis and neutrophilia.

1. Leukocyte adhesion deficiency
Pathophysiology
• Defect in CD18-containing integrins
• Impaired leukocyte adhesion & endothelial
transmigration
Clinical features
• Skin & mucosal infections (eg, cellulitis, periodontitis)
without pus formation
• Impaired wound healing
• Delayed umbilical cord separation (age >3 weeks)
Laboratory
findings
• Leukocytosis & neutrophilia