Zoonotic transmission of diphtheria toxin-producing Corynebacterium ulcerans.

BACKGROUND: Diphtheria caused by toxin-producing Corynebacterium ulcerans is a re-emerging human disease that can cause local and systemic sequelae. In Australia, toxigenic diphtheria is a rare notifiable communicable disease, due to high-vaccination coverage. The public health management of cutaneous cases of toxigenic C. ulcerans varies between jurisdictions, as opposed to the more uniform public health response to toxigenic Corynebacterium diphtheriae presenting as respiratory or laryngeal diphtheria. AIM: To report a case of zoonotically acquired C. ulcerans, review evidence on the zoonotic reservoir and reported transmission events, and examine public health guidelines for the management of human and animal contacts. METHODS AND RESULTS: In this case report, we detail our case investigation, treatment and public health management, including contact tracing and an approach to animal testing. We successfully identified companion canines as probable sources for the human case, with WGS confirming the link. The zoonotic disease link of C. ulcerans to domestic and agricultural animals is established in the literature; however, the management of animal contacts in human cases is inconsistent with jurisdictional or national guidelines. CONCLUSIONS: While a rare disease, a consistent approach to public health management is warranted to systematically elucidate the disease source and improve understanding of transmission.

Sebaceous carcinoma in Western Australia: A registry-based study of site-related outcomes.

Sebaceous carcinoma is a rare cutaneous malignancy which is typically regarded as relatively aggressive and has traditionally been subdivided into periorbital or extraorbital tumours. We conducted a retrospective review of all cases of sebaceous carcinoma reported to the Western Australian Cancer Registry between 1987 and May 2019. The incidence of sebaceous carcinoma in Western Australia has increased over the last three decades, with extraorbital tumours being much more common than periorbital tumours. Very few sebaceous carcinomas have led directly to the death of patients; however, adverse outcomes were more likely with periorbital tumours, in particular local recurrence and the need for major surgical intervention.