HISTORY AND CLINICAL FINDINGS: A 27-year-old man was referred to the 
dermatological out-patient clinic because of inflammatory changes in the oral 
mucosa of unknown cause. 5 months earlier he had been diagnosed as having 
Crohn's disease of the terminal ileum. On both sides of the buccal mucosa there 
were rough erythematous vegetations and disseminated miliary abscesses, which 
extended to the labial gingiva and the soft palate. Further physical examination 
was unremarkable.
INVESTIGATIONS: Several inflammatory parameters were increased: C-reactive 
protein 100 mg/l, erythrocyte sedimentation rate 55/88 mm, eosinophilic cationic 
protein 35.8 ng/ml (normal range 2.3-16 ng/ml). White cell count was normal 
(7,25/nl), with a lymphocytopenia of 11.9%. There was no eosinophilia. 
Haemoglobin was reduced to 11.6 g/dl and the platelets raised to 526/nl. Smears 
of the oral mucosa showed no fungal, viral or bacterial infection. Biopsy 
revealed leucocytic microabscesses in the epithelium, granulation tissue and 
flat ulcerations with adjoining superficial necrotic zones.
DIAGNOSIS, TREATMENT AND COURSE: The clinical and histological picture as well 
as the association with Crohn's disease (CD) suggested pyostomatitis vegetans 
(PV). The PV was treated with disinfectant mouth washes which improved the 
subjective findings. Budesonide was given for CD.
CONCLUSION: PV is a rare and usually isolated condition, but it can also occur 
in association with a chronic gastrointestinal disease such as ulcerative 
colitis and Crohn's disease. The diagnosis of PV indicates a thorough 
gastroenterological investigation.