RESUMO
Leukocyte adhesion deficiency type 1 (LAD 1 - CD18 deficiency) is a rare disease characterized by disturbance of phagocyte function associated with less severe cellular and humoral dysfunction. The main features are bacterial and fungal infections predominantly in the skin and mucosal surfaces, impaired wound healing and delayed umbilical cord separation. The infections are indolent, necrotic and recurrent. In contrast to the striking difficulties in defense against bacterial and fungal microorganisms, LAD 1 patients do not exhibit susceptibility to viral infections and neoplasias. The severity of clinical manifestations is directly related to the degree of CD18 deficiency. Here, a 20 year-old female presenting a partial CD18 deficiency that developed a megakaryocytic (M7) acute myeloid leukemia is described for the first time. The clinical features of the patient included relapsing oral thrush due to Candida, cutaneous infections and upper and lower respiratory tract infections, followed by a locally severe necrotic genital herpetic lesion. The patient's clinical features improved for a period of approximately two years, followed by severe bacterial infections. At that time, the investigation showed a megakaryocytic acute myeloid leukemia, treated with MEC without clinical improvement. The highly aggressive evolution of the leukemia in this patient suggests that adhesion molecules could be involved in the protection against the spread of neoplastic cells.