The main sign of the disease is life-threatening, recurrent bacterial or fungal soft tissue infections.

Omphalitis (infection of the umbilical cord stump) is common shortly after birth.

Other signs include delayed separation of the umbilical cord, periodontal disease, elevated neutrophils, and impaired wound healing, but not increased vulnerability to viral infections or cancer.

The deficiency of LFA-1 causes neutrophils to be unable to adhere to and migrate out of blood vessels, so their counts can be high.

The lack of CR3 interferes with chemotaxis, phagocytosis, and respiratory burst[citation needed] Flow cytometry with monoclonal antibodies is used to screen for deficiencies of CD18.