Leukocyte adhesion defect (LAD) is an inherited defect of phagocytic function. This disorder is characterised by delayed separation of the umbilical cord, severe recurrent bacterial infections, impaired formation of pus, and high leukocyte counts. The granulocytes have severe defect in their chemotactic mobility and endocytosis. The disease is attributed to the absence of the leukocyte adhesion molecules. (CD11/CD18), which can be verified with monoclonal antibodies. The authors describe the disease-process of the first patient diagnosed in Hungary. Perinatally the omphalitis, periumbilical abscess and periproctal abscess leading to rectovaginal fistula, in the first months the otitis, mastoiditis, and expressed leukocytosis referred to the impaired function of phagocytic cells, which was verified by laboratory tests as well. The decreased inflammation and cicatrization were also striking. This severe form of LAD can be cured only by bone marrow transplantation with preliminary sanitation of the foci of infection. It took about six months. Unfortunately, the patient died of sepsis immediately before transplantation.