Macrolide resistance in Campylobacter jejuni and Campylobacter coli

Infection with Campylobacter jejuni is now considered to be the most common cause of acute bacterial gastroenteritis in humans worldwide. It occurs more frequently than infections caused by Salmonella species, Shigella species, or Escherichia coli O157:H7. Although C. jejuni is also recognized for its association with serious post-infection neurological complications, most patients with C. jejuni infections have a self-limited illness. Nevertheless, a substantial proportion of these infections are treated with antibiotics. These include severe and prolonged cases of enteritis, infections in immune-suppressed patients, septicaemia and other extra-intestinal infections. Under these circumstances, erythromycin is often recommended as the drug of first choice. However, erythromycin-resistant Campylobacter have emerged during therapy with macrolides. Moreover, the widespread use of macrolides, including erythromycin, in veterinary medicine has accelerated this resistance trend. Several countries including Canada, Japan and Finland have reported C. jejuni isolates with low and stable rates of macrolide resistance. In contrast, the increasing level of macrolide resistance in C. jejuni is becoming a major public health concern in other parts of the world such as the United States, Europe and Taiwan. Macrolide resistance in Campylobacter is mainly associated with point mutation(s) occurring in the peptidyl-encoding region in domain V of the 23S rRNA gene, the target of macrolides. Several rapid and practical techniques have recently been developed for the identification of macrolide-resistant isolates of C. jejuni. The aim of this mini-review is to give an overview of the worldwide distribution of macrolide resistance in C. jejuni and Campylobacter coli as well as its possible association with the massive use of these agents in food animals. Mechanisms implicated in macrolide resistance in C. jejuni and also techniques that have been developed for the efficient detection of macrolide-associated mutation(s) will be discussed in detail.