Rare manifestations of cutaneous diphtheria: a case report

This case report presents an exceptionally rare and atypical presentation of diphtheria in a 17-year-old female of Hausa ethnicity residing in an area with an elevated incidence within Kano State, Nigeria. By the end of 39th epidemiological week of 2023, only two cases of cutaneous diphtheria have been reported among 5,811 cases managed at MMSH diphtheria treatment center (DTC), representing approximately 0.035% of all diphtheria cases during that time period.

A 17-year-old Hausa female presented with a 3-day history of throat discomfort, malaise, and muffled speech. Physical examination revealed a pseudomembrane covering the tonsillar pillars, grade 3 tonsillar enlargement, and an unusual genital manifestation characterized by extensive vulval edema, severe pain, and a large, greyish patch extending into the vaginal introitus. Her medical history was significant for recent exposure to diphtheria and the emotional impact of her sibling's death from the same disease. Diagnostic tests, including throat swab culture and histocytology, confirmed diphtheria in the throat and vulvovaginal regions. The patient was promptly initiated on diphtheria antitoxin, Azithromycin, and innovative sitz baths with hydrogen peroxide. After 4 days of Sitz bath therapy, complete pseudomembrane clearance was observed, and the patient's symptoms resolved.

This case underscores the complexity of diphtheria presentations, particularly with rare pseudomembranes in both throat and vaginal regions. The successful management, combining traditional and innovative therapies, highlights the importance of recognizing and addressing unusual manifestations promptly. The potential role of auto-inoculation and the efficacy of interventions like hydrogen peroxide sitz baths warrant further investigation. Overall, this case contributes to the understanding of diverse diphtheria presentations, guiding future clinical strategies for management of diphtheria cases and emphasizing the imperative of comprehensive vaccination efforts.