What is believed to be the first clinical isolate of Bordetella hinzii in the UK, from a patient with myelodysplastic syndrome, is described. This patient had no known avian exposure, and the source of the organism remains unknown. It appears that the underlying immune deficiency of the patient increased the susceptibility to opportunistic infection with this organism. Human infection with B. hinzii is rare and this species is difficult to differentiate from Bordetella avium by routine phenotypic methods. Confirmation can be reliably achieved using genotypic methods, and the greater mutational variation of the ompA gene compared to other genes (e.g. 16S rRNA gene) allows unambiguous identification of this and other non-classical Bordetella species.