Cutaneous ulcers revealing diphtheria: A re-emerging disease imported from Indian Ocean countries?

INTRODUCTION

Diphtheria due to Corynebacteriumdiphtheriae (C. diphtheriae) has become rare in developed countries. In France only 10 cases of toxigenic diphtheria have been reported since 1989, in all cases causing pharyngitis and all emanating from endemic countries with exception of one contact case. We report herein 13 cases with cutaneous diphtheria, in 5 of which diphtheria toxin was produced, and all imported into France between 2015 and 2018.

OBSERVATIONS

Thirteen patients aged 4 to 77 years presented painful and rapidly progressive round ulcerations of the legs, that were superficial and in some cases purulent, with an erythematous-purple border covered with greyish membrane. Bacteriological sampling of ulcers revealed the presence of C. diphtheriae. Only 6 patients had been properly immunized over the preceding 5 years.

DISCUSSION

These cases underline the resurgence of cutaneous diphtheria and the circulation of toxigenic strains in France following importation from Indian Ocean countries. This may constitute an important reservoir for ongoing transmission of the disease. Re-emergence of this pathogen stems from the current migratory flow and decreased adult booster coverage.

CONCLUSION

Cutaneous diphtheria should be considered in cases of rapidly developing painful skin ulcers with greyish membrane, especially among patients returning from endemic areas, regardless of their vaccination status. The clinician should order specific screening for C. diphtheriae from the bacteriologist, since with routine swabbing Corynebacteriaceae may be reported simply as normal skin flora. Vaccination protects against toxigenic manifestations but not against actual bacterial infection. Early recognition and treatment of cutaneous diphtheria and up-to-date vaccination are mandatory to avoid further transmission and spread of both cutaneous and pharyngeal diphtheria.

Cutaneous Corynebacterium Infection Presenting with Disseminated Skin Nodules and Ulceration

In the context of the European migrant crisis, more and more cases of cutaneous diphtheria are seen. A typical presentation includes painful cutaneous ulcerations with grayish-whitish pseudomembranes. Here we present 2 male Eritrean patients suffering from cutaneous nontoxigenic Corynebacterium diphtheriae (patient 1) and Corynebacterium striatum (patient 2) infection.

Cutaneous Corynebacterium diphtheriae: A traveller's disease?

A Canadian soldier incurred a nonhealing traumatic skin ulcer while on duty in Somalia. The diagnosis of localized cutaneous diphtheria was confirmed by isolation of a toxigenic strain of Corynebacterium diphtheriae from the ulcer. The patient was placed in isolation and treated with erythromycin and penicillin for 10 days without antitoxin. He was released when two consecutive daily cultures were negative. Public health officials evaluated his wife, two children and close contacts for carriage, but no carriers or secondary cases were identified. Cutaneous diphtheria as a diagnostic and management patient problem and potential public health problem are discussed.