Correction of leukocyte adhesion deficiency type II with oral fucose

We describe a simple, noninvasive, and effective therapy for leukocyte adhe sion deficiency type II (LAD II), a rare inherited disorder of fucose metab olism. This disorder leads to an immunodeficiency caused by the absence of carbohydrate-based selectin ligands on the surface of neutrophils as well a s to severe psychomotor and mental retardation. The fucosylation defect in LAD II fibroblasts can be corrected by addition of L-fucose to the culture medium. This prompted us to initiate dietary fucose therapy on a patient wi th LAD II. Oral supplementation of fucose in this patient induced the expre ssion of fucosylated selectin ligands on neutrophils and core fucosylation of serum glycoproteins. During 9 months of treatment, infections and fever disappeared, elevated neutrophil counts returned to normal, and psychomotor capabilities improved. (C) 1999 by The American Society of Hematology.