Pyostomatitis Vegetans in a Patient With Crohn's Disease: A Case Report on the Effectiveness of Ustekinumab

INTRODUCTION: Pyostomatitis vegetans (PV) is a rare inflammatory stomatitis that is seen in association with inflammatory bowel diseases (IBD). The treatment approach of PV depends on the presence of coexisting IBD. In the absence of IBD, topical steroids are often used, but in many cases, there is a need for systemic therapy. To date, there have been no published reports on the use of ustekinumab for PV.

CASE: A 26-year-old female with long standing Crohn’s disease presented for further evaluation of recurrent lip and chin swelling as well as loose bowel movements and abdominal pain. She was diagnosed at the age of 8 with Crohn’s disease and was treated with mesalamine and azathioprine which maintained her in remission for 10 years. Overall, she remained well, but would experience mild gastrointestinal symptoms along with recurrent episodes of chin and lip swelling a couple of times a year. Upon presentation, she had severe swelling of her lips and chin with neck erythema. Additionally, the patient had lower abdominal pain, and loosening of her bowel movements. Endoscopic evaluation with biopsies was consistent with active Crohn's disease. After consulting with our dermatology colleagues, it was decided to give the patient a short course of steroids as she was in extreme distress from her PV. She was then started on ustekinumab monotherapy (initial dose 260 mg intravenously), especially given her history of mild psoriasis. Shortly after, her pustules crusted and then disappeared. The patient has been on ustekinumab 90 mg subcutaneously every 8 weeks for the past 7 months. Since then, her lip and chin swelling improved remarkably without recurrence. Additionally, her Crohn’s disease has been in remission based on symptoms and noninvasive inflammatory markers.

DISCUSSION: PV is a rare inflammatory stomatitis that is often seen in association with IBD. PV oral lesions are benign. They consist of multiple small white and yellow pustules with an erythematous and edematous mucosal background. If they rupture, these pustules fuse and lead to a “snail-track” appearance. Those lesions can be painful or painless. On histology, intra and sub-epithelial micro abscesses with high number of eosinophils and neutrophils can be seen. The intestinal symptoms usually precede oral PV by several months or years. The clinical course of PV parallels the activity of IBD. As for treatment of PV, the approach depends on the presence of coexisting IBD. In patients with IBD, management of PV is often based on the therapy utilized to treat the underlying IBD. In the absence of IBD, topical steroids are efficacious, but in many cases, there will be a need for systemic therapy. Prior to this case, there have been no published reports on the use of ustekinumab for the treatment of PV.

CONCLUSION: PV is a rare inflammatory stomatitis and it is often seen in association IBD. One treatment option that might be considered is ustekinumab, given its low immunogenicity and favorable safety profile.