Pyostomatitis Vegetans

Are You Confident of the Diagnosis?

Pyostomatitis Vegetans is a rare, pustular, oral condition associated with inflammatory bowel disease and other underlying gastrointestinal diseases. The gastrointestinal diagnosis typically precedes the oral diagnosis by years. This is the oral presentation of pyoderma vegetans (vegetative plaques in the intertriginous folds).

Characteristic findings on physical examination

On oral examination, the buccal mucosae, gingivae and soft palate are the most commonly affected surfaces (Figure 1). Erythema, edema, pustules and superficial erosions are the classic findings. However, pustules can coalesce and break open to form larger ulcerations with a hyperkeratotic (snail-edge) border and cobblestoning can be seen as well. Pain is reportedly minimal in comparison to the impressive clinical presentation.

Figure 1.

Pyostomatitis Vegetans.

Expected results of diagnostic studies

Histopatholgy of newer, pustular lesions demonstrates sub and intraepithelial neutrophilic and eosinophilic abcesses overlying a dense lymphocytic dermal inflammation (Figure 2, Figure 3). Older lesions become less pustular and more hyperplastic with a more chronic lymphocytic infiltrate. A peripheral eosinophilia is common. Cultures are usually negative showing only normal flora. Findings on gastrointestinal evaluation would most commonly be consistent with ulcerative colitis.

Figure 2.

Pseudoepitheliomatous hyperplasia with abundant intraepithelial and submucosal mixed inflammation and many neutrophils.

Figure 3.

Abundant acute inflammation.

Diagnosis confirmation

The differential diagnosis includes: primary herpes simplex virus (HSV) eruption (grouped superficial erosions, polymerase chain reaction (PCR) positive for HSV), lichen planus (lace-like reticultation, hyperkeratosis or ulceration, characteristic histology and direct immunofluorescence), bullous dermatoses (sloughing and erosions, characteristic histology and direct immunofluorescence), erythema multiforme (oral involvement often extending to lips, ocular/cutaneous/genital involvement, HSV) and orofacial granulomatosis (periodic swelling, eventual firmness, rougher texture and loss of pliability, H&E with granulomas in mature lesions).

Who is at Risk for Developing this Disease?

Those at risk include patients with inflammatory bowel disease and young to middle-aged adults (range 5 to 70 years) with a male to female ratio of 3:1.

What is the Cause of the Disease?

Pyostomatitis vegetans is an inflammatory disorder of unknown etiology.


Because of the association with inflammatory bowel disease, cross-reaction between bowel and oral antigens is hypothesized.

Systemic Implications and Complications

Pyostomatitis vegetans is associated with inflammatory bowel disease (ulcerative colitis and Crohn’s disease) and other gastrointestinal disease (sclerosing cholangitis and hepatitis). Referal to gastroenterology is indicated.

Treatment Options

Treatment is aimed at the underlying gastrointestinal disease. If local antiinflammatory adjuvant therapy is needed, mid- to high-potency corticosteroid gels or solutions can be used.

-Fluocinonide or clobetasol gel applied two to three times a day

-Dexamethasone solution 0.5mg/5ml 5 to 10ml swish and spit two to three times a day

Optimal Therapeutic Approach for this Disease

Systemic treatment should be aimed at the underlying gastrointestinal disease and guided by the patient’s gastroenterologist.

Patient Management

Chronic treatment is often needed and should be monitored both by gastroenterology and dermatology. Disease remission postsurgically in a patient with ulcerative colitis has been reported.

Unusual Clinical Scenarios to Consider in Patient Management


What is the Evidence?

Ayangco, L, Rogers, RS, Sheridan, PJ. “Pyostomatitis vegetans as an early sign of reactivation of Crohn's disease: a case report”. J Periodontol. vol. 73. 2002. pp. 1512-6. (Case report of disease reactivation where oral symptomatology preceded bowel symptoms.)

Calobrisi, SD, McDonald, JS. “Pyostomatitis vegetans associated with ulcerative colitis. Temporary clearance with fluocinonide gel and complete remission after colectomy”. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. vol. 79. 1995. pp. 452-4. (Case report of successful control using a topical corticosteroid until disease remission was obtained by colectomy.)

Hegarty, AM, Barrett, AW, Scully, C. “Pyostomatitis Vegetans”. Clin Exp Dermatol. vol. 29. 2004. pp. 1-7.

McCarthy, FP. “Pyostomatitis vegetans: report of three cases”. Arch Dermatol Syph. vol. 60. 1949. pp. 750-64. (The article introducing the terminology of pyostomatitis vegetans.)