Recent cases of non-toxigenic Corynebacterium diphtheriae in Scotland: justification for continued surveillance

In recent years, there has been an increase in incidences of non-toxigenic Corynebacterium diphtheriae causing disease. Non-toxigenic strains generally cause persistent sore throats and severe pharyngitis/tonsillitis although complications of invasive disease such as endocarditis, septic arthritis, splenic abscesses and osteomyelitis are not uncommon (Wilson, 1995; Belko et al., 2000; von Hunolstein et al., 2002). Currently there is an overall lack of information on the prevalence of non-toxigenic C. diphtheriae colonization, prevalence and disease in the population due to a reduction in routine screening for this organism (Wagner et al., 2010). Here we describe three recent cases of non-toxigenic C. diphtheriae infection in Scotland and review the recent cases in the Grampian area.