Inverted sigmoid diverticulum: a misleading polyp

tals, thus characterizing a granulomatous reaction. 7 The initial ulcerations usually heal by 8 weeks and either disappear or remain radiographically weeks later.8.9 Other later descriptions include fistulas, pedunculated or sessile lesions abscesses, masses, and proctitis with barium flecks.5.7.8.l~ The rare finding of a barium granuloma more than 2 years after barium enema has been described in two previous cases. In the patient reported by Lewis et al./ an ulcerated I-em lesion at 6 em from the anal verge was seen 2 years after barium enema. In the case of Broadfoot and Martin,a similar to ours, sigmoidoscopy 26 months after barium enema revealed a "smooth to irregular swelling covered by smooth mucosa with possible calcified tissue beneath the mucosa." It appears then that the long-term appearances of persistent barium granulomas is variable. A barium granuloma should be considered when faced with a rectal lesion after a barium enema. The diagnosis is made by biopsy, and it is best to alert the pathologist to look for barium-laden histiocytes in the rectal tissue. l l The natural history of barium granulomas, i.e., resolution, persistent ulceration, or persistent intramucosal lesion remains to be defined. Richard S. Elloway, MD Peter H. DeRidder, MD Division of Gastroenterology William Beaumont Hospital Royal Oak, Michigan

REFERENCES 1. Beddoe HL, Kay S, Kaye S. Barium granuloma of the rectum.

Figure 1. Endoscopic view of a 3-year-old rectal barium granuloma. The lesion was non-raised, pale white, and 5 mm across. Figure 2. Biopsy specimen from the intramucosal barium lesion shown in Figure 1 showing rectal mucosa with histiocytes (arrows) filled with barium (H & E; original magnification x250).

rectum was in 1954, and it had the appearance of a pedunculated tumor. l Lewis et al. 2 found at least 35 cases in the world literature in his 1975 review. By 1986 there were less than 45 cases in the English literature. 3• 4 These previous cases report on lesions that differ endoscopically from that of our patient. The reason for this appears to be the time the lesion was viewed after barium enema, and the nature of the iatrogenic infusion. Animal studies have been inconsistent, but the injection of unsterile barium usually creates a classic ulceration of the bowel wall covered by slough and surrounded by indurated elevated borders, and overhanging ragged mucosa. 5 This typical early appearance was either not seen or missed in our case 3 weeks after barium enema. Such a finding is consistent with previous reports of the relatively inert and non-toxic effect of small amounts of barium on body tissues. 5 The fact that most barium granulomas of the rectum occur within 8 em of the anal verge strongly suggests that insertion of the enema tip probably lacerates the rectal wall to some degree, and barium is able to enter the deeper tissues. 6 An inflammatory reaction ensues with a collection of cells (fibroblasts, multinucleated giant cells, macrophages, and lymphocytes) around the intracytoplasmic barium sulfate crysVOLUME 37, NO.5, 1991

JAMA 1954;154:747-9. 2. Lewis JW, Kerstein MD, Koss N. Barium granuloma of the rectum: an uncommon complication of barium enema. Ann Surg 1975;181:418-23. 3. Broadfoot E, Martin G. Barium granuloma of the rectum. Aust RadioI1977;21:50-2. 4. Arlow FL, D'Angelo DM. Barium granuloma mimicking rectal carcinoma. Henry Ford Hosp Med J 1986;34:213-4. 5. Gaston EA. Barium granuloma ofthe rectum. Dis Colon Rectum 1969;12:241-7. 6. Gardiner H, Roscoe EM. Barium peritonitis a new therapeutic approach. Am J Surg 1973;125:350-2. 7. Rand AA. Barium granuloma ofthe rectum. Dis Colon Rectum 1966;9:20-32. 8. Carney JA, Stephens DH. Intramural barium (barium granuloma) of colon and rectum. Gastroenterology 1973;65:316-20. 9. Carter RW. Barium granuloma of the rectum: a complication of diagnostic barium enema examinations. AJR 1963;89:880-2. 10. Weitzner S, Law DH. Barium granuloma of the rectum. Dig Dis 1972;17:17-22. 11. Saliero JV, Costa Santos C. Barium "granuloma" ofthe rectum a light and electron microscopic analysis. J Submicrosc Cytol 1983;15:1089-94.

Inverted sigmoid diverticulum: a misleading polyp To the Editor: Inverted sigmoid diverticula are polyp-like lesions which may confuse endoscopists. We encountered two cases of such lesions. In the first one, diagnosis was made after a sigmoidectomy, and in the second one after an inadvertent endoscopic removal. The first patient was a 45-year-old man. He complained 587

suits may have not been reported. We believe that endoscopic removal of inverted diverticula should be avoided if possible. O. Dumas, MD

C. Jouffre, MD

R. Desportes, MD J. P. Etaix, MD C. Barthelemy, MD J. C. Audigier, MD Department of Gastroenterology and Hepatology C.H.U. Saint-Etienne Nord Cedex, France

REFERENCES Figure 1. Inverted sigmoid diverticulum presenting as a voluminous, purplish polyp.

of recurrent rectal bleeding. At sigmoidoscopy numerous diverticula were found, and a purplish, pedunculated polypoid structure of 3 em in diameter with a thick stalk (Fig. 1). Sigmoidectomy was performed. The macroscopic appearance of the "polyp" was that of an inverted diverticulum. At histological examination, there was no adenomatous structure but only mucosal and submucosal tissue with edema, dilated capillaries, and iron-laden macrophages. No further bleeding was observed after 6 years of follow-up. The second patient was a 62-year-old man who suffered from abdominal pain, fever, and diarrhea. Colonoscopy revealed sigmoid diverticula and multiple congestive polypoid lesions, suggesting inverted diverticula. One of them, however, was macroscopically considered to be an adenomatous lesion, and a polypectomy by snare electrocoagulation was performed without complication. The lesion was entirely removed and histologically identified as an inverted diverticulum with dystrophic colonic mucosa and many blood vessels. In diverticular disease, different kinds of polypoid lesions can be found: true adenomatous polyps, metaplastic and transitional polyps, polyp-simulating mucosal prolapse syndromes, and inverted diverticula. 1 • 2 The latter have been rarely reported3 and may be responsible for severe bleeding if no other colonic source can be detected. Their axis is composed of mucosa and submucosa, edema in the submucosa with vascular hyperplasia, and inflammatory cells. Muscularis propria and serosa can be present. There is no adenomatous tissue. These "polyps" have a misleading macroscopic appearance, particularly in the case of a single lesion. Radiographic aspects have been described but are not sufficient for diagnosis. 3 This must be considered in every polypoid lesion in a diverticular segment, particularly if voluminous, soft, congestive, and broad-stalked, presenting the characteristic "pillow-sign" with radiating folds. 4 Biopsies of such lesions can be helpful. Inverted diverticula have a soft and easily compressible consistency.2 Although endoscopic treatment of inverted diverticula is not recommended because of the risk of perforation and bleeding, uneventful diverticulectomies have been reported,4.5 as in our second patient. When a perforation occurs, it is probably sealed by pericolic fat and contractions of the hypertrophied muscular wall. However, other diverticulectomies with less good re588

1. Franzin G, Fratton A, Manfrini C. Polypoid lesions associated

with diverticular disease of the sigmoid colon. Gastrointest Endosc 1985;31:196-9. 2. Mathus-Vliegen EMH, Tytgat GNJ. Polyp-simulating mucosal prolapse syndrome in (pre-)diverticular disease. Endoscopy 1986;18:84-6.

3. Shah AN, Mazza BR. The detection of an inverted diverticulum by colonoscopy. Gastrointest Endosc 1982;28:188-9. 4. Schuman BM. Endoscopic diverticulectomy in the sigmoid colon. Gastrointest Endosc 1982;28:189-90. 5. Ladas SD, Prigouris SP, Pantelidaki C, Raptis SA. Endoscopic removal of inverted sigmoid diverticulum-is it a dangerous procedure? Endoscopy 1989;21:243-4.

Duodeno-pancreatico-choledochal rupture of pseudocyst To the Editor: We report a case in which a pancreatic pseudocyst ruptured into the duodenum, common bile duct, and pancreatic duct simultaneously. Diagnosis was made on barium meal examination and confirmed by ERCP. A 37-year-old alcoholic man was admitted with a 11/2 years history of upper abdominal pain radiating to the back associated with bilious vomiting. His symptoms worsened 11/2 months before admission and simultaneously he also noticed a lump in the upper abdomen. He was diagnosed to have a pancreatic pseudocyst and underwent surgical cystogastrostomy. He remained symptomatic and became icteric, although the epigastric mass decreased in size. Examination revealed a thinly built, icteric sick looking, fully alert patient with a 15- x 10-cm mildly tender, firm, irregular, and fixed mass in the epigastrium, left hypochondrium, and umbilical region. Ultrasound of the abdomen showed heterogeneous pancreas mainly in the region of body and tail. Its outline was irregular. CT scan demonstrated a swollen head and body of the pancreas with obliteration of peripancreatic fat planes. Barium meal showed a pseudocyst in the head of the pancreas communicating with the second part of the duodenum. The contrast could be seen flowing into the pancreatic duct, common bile duct, and intrahepatic biliary radicals. Duodenoscopy (Olympus GIF-QlO) confirmed a wide mouth communication between the pseudocyst and duodenum. The endoscope was advanced into the pseudocyst and openings of bile duct and pancreatic duct were seen and contrast injected into them delineated the respective ducts GASTROINTESTINAL ENDOSCOPY