For example, a multicenter study of 132 LAD patients found that those with lower CD18 expression (<2%) presented early in life with omphalitis, delayed umbilical cord separation, and recurrent skin and soft tissue infections, while those with higher CD18 expression (>30%) often presented later with chronic skin ulcers as the most common manifestation [67]. The gene discussed is ITGB2; the disease is chronic ulcer of skin.