[Type 1 hyper-IgM syndrome diagnosed in a 28-year-old patient with recurrent infections since childhood].

We report a male patient who was diagnosed as having hyper-IgM syndrome at the age of 28 years old. The patient had a history of recurrent infectious diseases since childhood such as bronchitis and otitis media, with decreased and increased levels of serum IgG and IgM, respectively. Genomic analysis of the CD40 ligand gene revealed deletion of six nucleotides from 475 to 480 followed by a T to A change at 481. These findings were compatible with the diagnosis of type 1 hyper-IgM syndrome. Bearing in mind the fact that only 20% of such patients survive over the age of 25, this patient is considered to be a rare case who was not actually diagnosed as having this disease until 28 years old.