Life-threatening Escherichia coli cellulitis in patients with haematological malignancies.

Cellulitis due to Escherichia coli is rare and usually secondary to a cutaneous portal of entry. Skin and soft tissue infections (SSTI) secondary to E. coli bacteraemia have been reported exclusively in immunodeficient patients. Here, we report two cases of serious cellulitis secondary to E. coli bacteraemia in patients with haematological malignancies. Both isolated strains belonged to phylogenetic group B2 and harboured some of the main virulence factor genes commonly found in extra-intestinal pathogenic E. coli (ExPEC), including neuC, iro and fimH. Cellulitis due to E. coli seems to be linked to the immunocompromised status of patients rather than to a highly virulent clone. Nevertheless, some of the virulence factors appear to be important because both isolates belong to phylogenetic group B2. This aetiology should be considered in SSTI in patients with haematological malignancies.