Duodenal 'pseudolipomatosis'

[Gastric micropneumatosis: a rare endoscopic entity]

The rarely described gastric micropneumatosis is caused by accumulating air in the mucus membrane. It may associate mainly with Helicobacter pylori positive atrophic gastritis or with pneumatosis due to gas producing bacteria or non-infectious causes. In our case the disorder was diagnosed in a 69 years old patient, taking clopidogrel, living in a nursing home, with history of hypertension, general arteriosclerosis, cerebral infarction, who was admitted to our department because of melaena and hematemesis. Upper endoscopy revealed a map-like, slightly raised, palm-sized area with yellowish spots on the posterior wall of the markedly inflamed stomach at the level of fundus - corpus border. Based on histology findings, that showed empty spaces among corpus glands, 10-20 microm in diameter, with no epithelial lining, the diagnosis was gastric micropneumatosis. The impaired mucosal integrity caused by mesenteric ischaemia and repeated vomiting were supposed as possible etiological factors, because 72 hours after the patient had stopped vomiting, control endoscopy showed regression, and the empty spaces were no more detectable in the histology samples. By this case report the authors would like to draw attention to a seldom diagnosed gastric injury, and discuss the factors that may predispose the development of gastric micropneumatosis.

Colonic pseudolipomatosis: clinical, endoscopical and pathological features in nine cases

Colonic pseudolipomatosis is a rare and benign condition. It is not well known by gastroenterologists and its pathogenesis is still unclear.

METHODS

All cases of colonic pseudolipomatosis seen between February 2002 and June 2004 at the Amiens Universisty Hospital were identified and analyzed.

RESULTS

During this period, 2099 colonoscopies were performed and 9 cases of colonic pseudolipomatosis were diagnosed (0.4%). Patients were all males aged from 41 to 67 (median age 52 years). They consulted for rectal bleeding (two patients), diarrhea (two patients) or abdominal pain (two patients). In three patients, colonic pseudolipomatosis was a fortuitous discovery during colonoscopy for polyp surveillance. The lesions presented as whitish and yellowish slightly elevated plaques ranging in size from a few millimeters to 4 cm. They extended over a two to 20 cm-long area, located in the right (two patients), transverse (four patients) or left colon (three patients). Microscopic examination showed empty spaces in the lamina propria measuring from 50 to 600 microm. They were negative for anti-CD31, CD34 and PS100 antibodies at immunohistochemistry and negative for Sudan black in three cases. The ultrastructural study showed in two cases round spaces containing small fibrillary protein-like deposits that might be lymph.

CONCLUSION

Colonic pseudolipomatosis is rare. Its pathogenesis is not well-known but could be due to gas invasion or extravasation of lymph into lamina propria, maybe induced by mucosal lesions related to barotrauma or certain colonoscope cleaning solutions.

Colonic pseudolipomatosis, microscopically classified into two groups

BACKGROUND

Colonic pseudolipomatosis is rare and the pathogenesis is controversial. The purpose of the present paper was to clarify endoscopic and histological characteristics of colonic pseudolipomatosis and to discuss the etiology.

METHODS

A total of 15 lesions from 14 patients was reviewed. They were able to be histologically classified into two groups on the basis of variety in size of the vacuoles: Group A, the ratio of largest vacuole to smallest vacuole in size is less than three, Group B, the ratio is more than four.

RESULTS

Four of 15 lesions were group A, and were endoscopically polypoid or flat lesions covered with normal-looking mucosa. They were microscopically characterized by (i) predominant location in the upper portion of the lamina propria; (ii) no submucosal involvement; (iii) less variation in vacuolar size; and (iv) no association with lymph follicles. The vacuoles of group A contained proteinaceous materials in two of four lesions. Group B (11 lesions) had small elevated mucosa with normal-looking surface or non-elevated reddish mucosa. Microscopically, the lesions were mainly located in the lower portion of the lamina propria, occasionally also in the submucosa, had variable-sized vacuoles, and were related to lymph follicles.

CONCLUSION

It is suggested that the vacuoles in group A contain fluid, and may indicate an abnormal stagnation of interstitial fluid. Microscopic appearance of group B is essentially similar to that of pneumatosis coli. It is thought that group B probably results from penetration of gas from the crypts into the mucosa during colonoscopy. It is unclear why group B had a preference for ileocecal valve and an association with lymph follicles.

Gastric pseudolipomatosis, usual or unusual? Re-evaluation of 909 endoscopic gastric biopsies

Microvesicular pneumatosis intestinalis, also called “pseudolipomatosis” for resembling fatty infiltration, is characterized by the presence of small gas voids in the gastrointestinal wall, especially in mucosa. These voids are not lined with epithelia. There are few reported cases about colon, duodenum and skin. Because there is only one case report about pseudolipomatosis in the stomach, we re-evaluated 909 endoscopic biopsies taken from gastric corpus to check the presence of pseudolipomatosis. We determined pseudolipomatosis foci in 3 percent (n = 27) of biopsies. In two cases there were pseudolipomatosis foci in endoscopic biopsies having otherwise normal histologic findings, while there were pseudolipomatosis foci in endoscopic biopsies of 25 patients with gastritis. Helicobacter pylori was found in 85% of biopsies having pseudolipomatosis foci. In this study, we presented some histopathologic characteristics of pseudolipomatosis seen in gastric mucosa.