Epiglottitis as the Presenting Sign of Mucous Membranous Pemphigoid: A Case Report

Laryngeal Mucous Membrane Pemphigoid as an Immune-related Adverse Effect of Pembrolizumab Treatment

Pembrolizumab is an immune checkpoint inhibitor (ICI) approved for multiple indications in a variety of malignancies. Although generally well tolerated, the potential for significant adverse effects, specifically immune related adverse effects (irAEs) needs to be taken into consideration. Several cases of bullous pemphigoid have been reported as a cutaneous adverse effect of ICIs since 2015, and there are recent reports of mucous membrane pemphigoid (MMP). We present the case of an 84-year-old male with metastatic urothelial carcinoma on treatment with pembrolizumab, who developed laryngeal mucous membrane pemphigoid as an irAE. The diagnosis was based on patient's clinical history and serologic testing, and supported by symptomatic improvement after ICI discontinuation and immunosuppression. Pembrolizumab-induced MMP is a newly described and infrequent irAE, requiring early suspicion and close monitoring for its diagnosis and management.

Laryngeal Pemphigoid Evolution and Response to Treatment

OBJECTIVE

This study aimed to present our experience in treating laryngeal pemphigoid (LP) patients, including disease course, treatment and treatment response, and to search for predictors of response to treatment.

STUDY DESIGN

A retrospective cohort study.

METHODS

The medical records of all patients with LP from March 2013 to August 2020 were reviewed. Potential relationships between disease severity and response to treatment and demographics, diagnosis, extent of laryngeal and extra-laryngeal involvement, comorbidities, immunostaining, and serology profile were explored.

RESULTS

Eight patients were included in the study (seven females, one male, mean age 79 years, mean follow-up 22 months). Diagnoses included mucous membrane pemphigoid (MMP, n = 5), bullous pemphigoid (BP, n = 3). Two patients achieved complete laryngeal remission, four achieved partial remission, and two had no remission. The time to achieve laryngeal disease control was longer than for extra-laryngeal disease (P = 0.02). Potential associations were found between the absence of immunoglobulin G (IgG)-type auto-antibodies deposits in the basement membrane zone and a laryngeal disease that responded to topical corticosteroids and between the presence of BP180-C-terminal IgG auto-antibodies and a resistant rapidly progressive laryngeal disease.

CONCLUSIONS

LP has a spectrum of severity, variable response and is more resistant to treatment. The absence of IgG-type auto-antibodies may indicate a response to topical corticosteroids. Based on our limited observation, the presence of IgG-type auto-antibodies that target BP180-C-terminal domain may indicate a more severe scarring disease. Early recognition of these "high-risk patients" will allow early initiation of advanced systemic treatment that may prevent the irreversible effects of scarring.

Persistent sore throat: a case of laryngeal mucous membrane pemphigoid

We present a case of a 72-year-old women who presented with a persistent sore throat and productive cough. On flexible nasendoscopy examination, she was found to have a fairly superficial ulcer affecting the laryngeal surface and tip of her epiglottis. On her second microlaryngoscopy and biopsy, direct immunofluorescent staining of the biopsy was analysed and the histological findings were in keeping with a diagnosis of mucous membrane pemphigoid (MMP). MMP is a rare chronic autoimmune condition characterised by the presence of blistering subepithelial lesions that can cause scarring. Laryngeal MMP affects only 1 in 10 million people and can lead to life-threatening airway compromise arising from scarring and stenosis. As there is a large spectrum of disease, it is important to adopt a multidisciplinary approach including dermatologists, otolaryngologists and ophthalmologists for prompt diagnosis and early recognition of potential complications, maximising functional outcomes for patients.