Angiodysplasia occurring in jejunal diverticulosis

The first case of angiodysplasia occurring in acquired jejuna! diverciculosis is reported. The patient presented with occult gastrointestinal bleeding and chronic anemia, and was created successfully by resection of a 25 cm long scpment of jejunum. Possible pathogenetic mechanisms for both angiodysplasia and jejuna! diverticulosis are discussed. Can J Gastroenterol 1990;4(4 ): 151-153

plication which is considered co be secondary to erosion o( normal blood vessels (3).This report describe~ a case of angiodysplasia which arose in cliverticula of acq uired Jejuna I di verciculosis and was the ca u~e of chronic blooJ loss.

CASE PRESENTATION
A 68-year-okl man was admitted en hospita l for investigation of iro n deficiency anemia.He had presemed four year~ earl ier with marked fa tigue and occult gastrointe~tinal bleeding, and wa~ found w have chronic antrnl gastritis, a large duodenal Ji veniculum, jejuna!diverticulosis and several ~mall benign coloni c adenomas.He had no evidence of inflammatory bowel disease or any disease of an imm unological nature which might be associated with jejuna!dive rcicul osis.There was no family history of jejuna I diverciculosis.His se rum B12 was normal.Despite removal o( the colonic adenomas, his scools continued co be positive for occult blood, and even though he was treated with iron , his hemoglobin remained about 80 g/L.Physical examination and a labelled red blood cell study for gastrointestinal tract bleeding were normal.A superior mcscnreric artenogram demonstrated ,111 early fill -ing jejuna[ vein and a vascular tuft (Figure l ), features comistent with a diagnosis of a ngioc.lysp las ia.Prev io u:.endoscopic examinations had revealed no angiodysplastic lesions in the large bowel, sromach or duodenum.The patient had no evidence of aortic stcnosis orother cardiac disease.He had not taken nonsteroida l arni-inflammatory drugs or potassium tablets which might have caused mucosa!damage and precipitated bleeding of the vascular Figure 1) Later arterial phase of superior mesenceric arteriogram showing early i,enous filling ( left arrow) and vascular tuft (right a1,ow) lesion.Preoperativcly, the superior mesenteric arteriogram was repeateJ and rhe catheter left in situ, with the tip lying in the fourth arcade of the jejuna[ branch artery.Ar laparotomy before the small bowel was manipulated, a bolus of methylene blue <lye was injecte<l into the catheter.A LS cm segment of miJ, jejunum involved by divcrticu losis wa, visibly stained.A 25 cm long segment of jejunum includi ng the stained segment was resected and primary anas, tomosis performed.T he patient has remained well four years later, with a normal hemoglobin.
Examination of the external surface of the resected jejunum showed that more than 20 paramesenteric diver, ticu la up to l .5 cm in ize were present.
A mesenteric artery was injected with a warm solution of gelatin and barium, and a specimen x-ray wa~ obtaineJ.
The resected segment of bowel was fixed in I 0% formali n.It was sectioned and a careful inspection rcvealeJ four (up to 3 mm in diameter) whi te mucosal lesions in separate diverricula.One of these had a small central depression.The mucosa away from the Jiverticuln was unremarkable.Microscopic exam ination showed that the lesions consisted of markedly dilated thi n walled mucosa!vessels (Figure 2) which were continuous with similar submucosal vessels, an appearance diagnostic of angiodysplasia.There was focal erosion of two of these lesions which was the cause of this patient's bleeding (Figure 3).

DISCUSSION
Jejuna! Jivercicu losis is not a rare condition; prospective autopsy studies using specimen insufflation techni4ues have documented an incidence of up to 4.6% (4).Although often innocuous, they are a potential cause of malabsorption, pseudo-obstruction, mechanical obstruction, volvulus, perforation, anemia, abscess formation and hemorrhage (3,5).Bleeding from jejuna! diverticulosis was first re po rted by Braithwaite in l 923 (6).Most bleed ing from diverticula arises from no rmal blood vessels.An injury LO the mucosa due co ulceration or direct trauma from concretions may breach vascu lar integrity.In the present case, the hemorrhage arose from angio<lysplasia in the diverticula.
Chronic intermittent obstruction of veins as they pass through the muscularis propri a ha~ been proposed in the rathogenesis of angiodysplas ia of the colon.The increased wa ll tension thar is present in the cecum accord ing to LaPlace's principle is the explanation given for the increased prevalence of angiodysplasia in chat part of the colo n (I).lnten::stingly, uncoordinated mu~cular contract ions with increaseJ intralumin a I pres~ure hav e been considered to be a cause of small bowel <liveniculo~is (3 ), and it is logical tn believe that such a state coulJ result in angiodysplasia in the jejunum.Indeed there has been one report of angiodysplas ia and diverriculosis occurring simultaneo us ly in a seg ment of the jejunum (7).In that case the angiodysplasia was located in bowel mucosa away fro m the diverticula.
In the present case th e ang iodysplasia was present in diverticula, although it is possible chat more sensi tive techniques m ay h ave Jisclosed evidence also of early angio<lysplasia in bowel away from lhe diverticula.The veins draining these divercicula dn not have to pab~ through the muscularb propria to reach the serosa and therefore cannot be obstructed at this level as has been suggested for angiodysplasia of the colon.Expansion nf lhese thin wa lled diverricula during periods of small intestinal contractions could poss ibly ca use obstruction of the veins.
T o the besr d the authors' knowledge this is the first ca~e of angiodysplas ia that has been reported rn occur in acquired jejuna!diverciculosis; therefore, the incidence of this occurrence is unknown.It might possibly be found more o ften if it was specifically CAN J GAS'm0ENTEROL VOL 4 NO 4 MAY/JUNE 1990 Angiodysplasia in jejuna!diverticulosis sought.It is also posbible that angiodysplasia might have been responsibl e for previou~ly reported cases o f hemorrhage fro m jejuna!diverticulobtS.