Background: Leukocyte adhesion deficiency type 1 (LAD-1) is a rare autosomal recessive primary immunodeficiency caused by defects in the ITGB2 gene encoding the β2-integrin subunit CD18 affecting 1 in a million people worldwide. Defective leukocyte adhesion and migration into infected tissues result in recurrent bacterial infections, impaired wound healing, absent or minimal pus formation, and delayed separation of the umbilical cord. Marked leukocytosis, particularly neutrophilia, is an important laboratory clue.
Case Presentation: We report a male neonate who presented at 27 days of life with fever, excessive crying, a non-healing right inguinal ulcer, and failure of the umbilical cord to separate. He was born at 41+2 weeks of gestation by LSCS with a birth weight of 3200 g following an uneventful antenatal and immediate postnatal period. 
The infant was exclusively breastfed. On evaluation, the umbilical cord remained attached and the inguinal ulcer showed poor local inflammatory response without significant pus formation. Laboratory investigations revealed marked leukocytosis with a total leukocyte count of 96,800/mm³ and an absolute neutrophil count of 82,280/mm³. C-reactive protein was positive, and blood culture grew coagulase-negative Staphylococcus. During hospitalization, the infant developed respiratory distress requiring CPAP, with radiological evidence of pneumonia. In view of the combination of delayed cord separation, severe neutrophilic leukocytosis, non-healing ulcer, and poor pus formation, a primary leukocyte adhesion defect was suspected. Flow cytometric evaluation demonstrated profoundly reduced expression of CD18 (0.00%) and markedly reduced CD11a expression (0.10%), supporting the diagnosis of LAD type 1.
Conclusion: LAD-1 should be considered in neonates presenting with delayed umbilical cord separation, recurrent or persistent bacterial infections, impaired wound healing, minimal pus formation, and unexplained marked neutrophilic leukocytosis. Early recognition and flow-cytometric assessment of β2-integrin expression can facilitate diagnosis and appropriate referral for definitive management.