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the first documented case involving the stomach was published in 1949 . by 1979 , a further 17 cases had been reported .
with improvement of diagnostic modalities over time , a study in 1997 reported that 8% of crohn 's disease involved the proximal gut ( mouth to jejunum ) ; however , more recently it has been suggested that 3050% of patients with crohn 's disease have proximal involvement . despite increasingly apparent proximal gut involvement ,
only 0.54% of crohn 's disease involves the stomach and/or duodenum . among patients with gastroduodenal involvement ,
a 25-year - old male was referred to our surgical department for investigation of 3 months of progressive gastric outlet obstruction . at presentation , the patient was unable to tolerate oral intake other than minimal amounts of water .
there was a 13-kg weight loss over this 3-month period ( weight 79 kg at presentation ) .
endoscopy at that time showed non - specific duodenitis , with biopsies taken from the gastric antrum and body as well as the duodenum .
gastric mucosa showed a mild - to - moderate increase in chronic inflammatory cells in the lamina propria with few focal polymorphs .
symptoms improved with eradication therapy . while subsequently on holiday in taiwan the symptoms returned , prompting further investigation .
as the patient remained unwell , he returned to new zealand for further evaluation in our centre .
the patient was a previously well non - smoker , with no significant medical or surgical history , taking only omeprazole ( prescribed during the prior work up ) .
there was a family history of crohn 's disease in a maternal aunt . on admission ,
abdominal examination revealed a soft , non - tender abdomen with no masses . on admission
c - reactive protein was 19 , with a normal white cell count ( 8.56  10/l ) .
iv fluids were given initially , and on day 3 of admission , a nasojejunal tube was placed endoscopically for enteric feeding .
endoscopy revealed a clear fluid in the gastric body , with acquired stenosis noted in the duodenal bulb , which was biopsied .
biopsy revealed non - specific inflammation , with brunner gland hyperplasia and foveolar metaplasia , reported as non - specific peptic duodenitis with no malignancy identified .
figure  2:endoscopic images of the lower oesophagus ( left ) and prepyloric stenosis ( right ) .
endoscopic images of the lower oesophagus ( left ) and prepyloric stenosis ( right ) .
endoscopic ultrasound was undertaken on day 8 of admission , which showed generalized thickening of the prepyloric deep mucosa with no discreet mass .
after discussion with a multidisciplinary team and subsequently with the patient and family , a decision was made for distal gastrectomy . on day 16 of admission ,
, a nodular lesion was noted in the pylorus which did not appear to involve the duodenum .
post - operatively , a histological diagnosis was made of crohn 's disease of the stomach , involving the duodenum .
figure  3:(a ) epithelioid granuloma away from sites of ulceration ( 20 h&e ) .
( b ) antral stomach with fissuring ulceration with crohn's - like lymphoid aggregate formation ( 10 h&e ) .
( b ) antral stomach with fissuring ulceration with crohn's - like lymphoid aggregate formation ( 10 h&e ) .
the patient was discharged 14 days after the operation when he was able to tolerate adequate oral intake for nutritional need .
subsequent anti - saccharomyces cerevisiae antibodies testing was positive for both igg ( 66 units / ml ) and iga ( 171 units / ml ) . the patient was subsequently started on azathioprine .
colonoscopy and gastroduodenoscopy with multiple biopsies have failed to show any evidence of further disease .
isolated gastroduodenal crohn 's disease represents a known diagnostic dilemma , with biopsies often showing non - specific inflammation . where tissue diagnosis is not conclusive , diagnosis should be considered based on symptoms , endoscopy , multiple biopsies and radiological findings . in the case reported here , the diagnosis was not apparent until histological analysis of the distal gastrectomy specimen was undertaken , despite multiple imaging modalities including ct and both external and endoscopic ultrasound , as well as histological analysis of multiple biopsies directly from the affected regions .
this is not unique among upper gastrointestinal crohn 's disease cases ; however , this case is unlike other cases to our knowledge due to the rapid onset of symptoms of gastric outlet obstruction with no long history of gastritis - like symptoms .
documented cases of isolated upper gastrointestinal crohn 's disease typically present with gastritis - like epigastric pain progressing over a number of years [ 79 ] .
symptoms of gastric outlet obstruction ( bloating , vomiting , postprandial pain and weight loss ) evolve in many cases , but almost universally after years of gastritis - like symptoms .
importantly , the case we present here did not have any previous history of gastritis - like symptoms , and had rapid onset of symptoms of gastric outlet obstruction with a 3-month progression from tolerating normal diet to tolerating only small sips of fluid .
we are aware of one other similar case in which a 42-year - old woman presented with a 9-month history of progressive epigastric pain , nausea , vomiting , weight loss and eventually food intolerance . despite multiple investigations including radiological and endoscopic imaging ,
a diagnosis was not able to be confirmed prior to the need for surgical intervention to relieve gastric outlet obstruction .
histological diagnosis confirmed crohn 's disease post - operatively ( the distal ileum was also found to be affected ) .
the similarities between the present case and this case from 1977 emphasize the difficulty in diagnosing atypical crohn 's disease , despite advances in medicine over the past 30 years .
we present a unique presentation of crohn 's disease in a 25-year - old male with a 3-month history of progressive gastric outlet obstruction symptoms including reflux , vomiting , postprandial pain and weight loss , with no other symptoms . 
 multiple imaging investigations as well as gastroscopic biopsies revealed a non - specific prepyloric lesion , without evidence of malignancy . 
 a distal gastrectomy was performed . 
 subsequent histological evaluation revealed gastroduodenal crohn 's disease . 
 follow - up revealed no evidence of disease elsewhere in the gastrointestinal system or systemically . while it is not uncommon for crohn 's disease to involve the stomach and duodenum , it is rare for gastroduodenal disease to be the initial presentation . 
 isolated gastroduodenal crohn 's disease typically presents with non - specific gastritis - like symptoms over a number of years . 
 this patient had a unique course of crohn 's disease with rapid onset of symptoms , predominantly relating to gastric outlet obstruction and no prior or subsequent history of gastrointestinal symptoms .