Identification of factors associated with treatment refractoriness of oral lesions in pemphigus vulgaris.

BACKGROUND: The oral mucosal lesions of patients with pemphigus vulgaris are known to show more treatment refractoriness than skin lesions.

OBJECTIVES: To identify which clinical and laboratory parameters may indicate treatment refractoriness of oral lesions in pemphigus vulgaris.

METHODS: This was a prospective study of 50 adults with pemphigus vulgaris and oral lesions; patients were given treatment appropriate for overall disease severity. Treatment refractoriness was defined arbitrarily as less than 75% reduction in oral objective Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) after treatment for 6 months.

RESULTS: Of 46 patients who completed the study, 17 (37%) were treatment refractory whereas 29 (63%) were treatment responsive. At baseline, the treatment refractory group had a significantly longer mean duration of disease (P = 0·02) and mean duration of oral lesions (P = 0·01), a higher percentage of lesions in the retromolar trigone (P = 0·05) and on the occlusion line along the buccal mucosa (P = 0·04), a higher percentage of deep/crateriform ulcers (P < 0·001) and erosions with a lichenoid hue (P < 0·001). Herpes simplex virus (HSV) DNA positivity, assessed by polymerase chain reaction in oral tissue scrapings (P = 0·02), was also significantly higher in the treatment refractory group. No other factors we tested for were statistically significant.

CONCLUSIONS: Treatment refractoriness of oral lesions was significantly associated with duration of disease/oral lesions; specific morphology and location of oral lesions; and the presence of HSV DNA in the oral cavity. These factors may forewarn the treating physician about a refractory course of oral lesions that may help with counselling patients.