Ileal Mass Research Articles

Challenging Diagnosis of Ileal Gastrointestinal Stromal Tumor Presenting with Obscure Digestive Bleeding

We report a case of a patient observed in emergency condition for recurrent episodes of massive obscure gastrointestinal bleeding that required surgical control. At laparotomy we found an ileal mass with the characteristics of a gastrointestinal stromal tumor (GIST) at histopathological analysis. GISTs should always be considered as a possible cause of obscure gastrointestinal bleeding, although they are often difficult to diagnose preoperatively. Laparotomy is sometimes the only way to obtain a diagnosis. Starting from this case, we reviewed the literature about GISTs, focusing our attention on their diagnosis and the possible surgical and nonsurgical therapies.

Estradiol-17β and linseed meal interact to alter visceral organ mass and hormone concentrations from ovariectomized ewes

To evaluate the estrogenic potential of secoisolariciresinol diglycoside (SDG) found in linseed meal (LSM) on visceral organ mass, IGF-I, and thyroid hormone (T 3 and T 4) concentrations, 48 multiparous, ovariectomized ewes (54.6 ± 1.1 kg) were used in a 3 × 4 factorial arrangement. Main effects were length of LSM feeding (0, 1, 7, or 14 d) and length of exposure to estradiol-17β (E 2) implant (0, 6, or 24 h prior to tissue collection). Implanting ewes with E 2 for 24 h increased liver mass relative to empty body weight (EBW; g/kg EBW) compared with ewes implanted for 0 or 6 h ( P ≤ 0.03), whereas feeding LSM for 14 d decreased liver mass compared with ewes fed LSM for 1 or 7 d ( P ≤ 0.02). There was an LSM × E 2 interaction ( P = 0.01) for duodenal mass (g/kg EBW), LSM, and E 2 tended ( P = 0.07) to influence the stomach complex mass; however, ileal mass was not affected. Neither LSM nor E 2 affected ( P ≥ 0.12) CYP2C or CYP3A mRNA expression or cellularity of the liver. Exogenous E 2 influenced circulating concentrations of IGF-I, T 3, and T 4. The estrogenic or anti-estrogenic potential of LSM is dependent upon the tissue, exposure to E 2, and the duration of LSM feeding. Feeding LSM during gestation, lactation, or during the grow-finish phase warrants further investigation.

A rare cause of intestinal obstruction due to an exophytic gastrointestinal stromal tumor of the small bowel

ABSTRACT Introduction: Gastrointestinal stromal tumors constitute a distinct group of rare gastrointestinal tract tumors that originate from the interstitial cells of Cajal. These jejunoileal lesions are a rare cause of obstruction but can be associated with substantial morbidity. Case: A 59-year-old woman presented to the emergency department with abdominal pain and distention. Physical exami-nation revealed tenderness and rebound in right lower quadrant. Computed tomography revealed a mass in lower right quadrant. A 9x9x4 cm exophytic ileal mass was observed at exploration. Preoperative diagnose was a small bowel tumor and then segmental resection and primary anastomosis were performed. Histopathological investigation revealed spindle cells that stained strongly for C-117, consistent with a diagnosis of a malign gastrointestinal stromal tumor. Conclusion: We conclude that exophytic small bowel gastrointestinal stromal tumors are rare lesions, which should be kept in mind by physicians among the diagnosis of small bowel obstructions in order to reduce substantial morbidity and mortality.

Jejunal perforation by a foreign body

A 52-year-old woman was referred to our surgical division for a 3-months history of abdominal pain, fever and leucocytosis. The abdominal computed tomography (CT) scanning showed only fluid spillage and minimal bowel dilatation. An explorative laparotomy was necessary with diagnosis of jejunal perforation by a foreign body (fish bone) with subsequent ileal resection. Even if intestinal perforation from foreign body is a really rare event, it should be considered in differential diagnosis of acute peritonitis. INTRODUCTION The diagnosis of small bowel perforation due to foreign bodies or fish bone is a rare event because most of these can pass through the gastrointestinal tract uneventfully. CT scan could help to detect foreign bodies; however, it did not show an optimal sensitivity. Endoscopy and surgery are fundamental for diagnosis and therapy. We report a rare case of jejunal perforation from foreign body (fish bone). CASE REPORT A 52-year-old woman was referred to our surgical division for a 3-months history of abdominal pain, fever and leucocytosis. The abdominal computed tomography (CT) scanning (Figure 1) made in another institution showed only a fluid spillage and minimal bowel dilatation. Furthermore, the patient previously (six weeks before) underwent an explorative laparoscopy for suspected gynaecological disease which resulted negative. Then the patient was admitted to our ward with suspected malignant pathology. An explorative laparotomy was necessary for worsening clinical conditions and diagnosis of jejunal perforation by a foreign body (fish bone) was made (Figure 2, 3). DISCUSSION Most of foreign bodies ingested pass through the gastrointestinal (GI) tract uneventfully within 1 week; the occurrence of bowel perforation is rare (less than 1%). In the present case a jejunal perforation with abscess due to a 4cm fish bone is reported. The patient underwent ileal resection. The diagnosis of small bowel perforation is very difficult. CT scan can really help in pre-operative diagnosis; however, small fish bones or fins are difficult to recognize preoperatively. CT scan showed a sensitivity of 71.4% in the detection of intra-abdominal fish bone. In recent series of gastrointestinal tract perforation by foreign body, numerous risk factors have been reported: alcohol or drug abusers, selected professions such as carpenters or dressmakers, persons who eat rapidly and/or with denture problems. In a special way, this last group without capacity of identifying small or hard items in forming a bolus, have a higher risk of foreign body ingestion. Furthermore, the dietary habits have a relevant role in the type of foreign bodies ingested with chicken bone more frequently reported in Mediterranean countries and fish bone in the Asiatic countries. In the majority of cases reported, ileocecum or recto-sigmoid tract are more frequently affected by perforation as sites of acute angulation. Clinical presentation is extremely variable depending on the site of perforation and extension of peritonitis. It can mimic appendicitis or other acute abdominal conditions. In most of the cases, diagnosis is obtained only with surgery. Laparoscopy has been used in the diagnosis of GI perforation from foreign body but it did not show high success rates. In this case, previous laparoscopy was not able to show any pathology and only final laparotomy identified the fish bone perforation. For this reason, even if intestinal perforation from foreign body is a rare event, it should be considered in differential Jejunal perforation by a foreign body 2 of 3 diagnosis of acute peritonitis. Figure 1 Figure 1. Abdominal computed tomographic scan showed fluid spillage. Figure 2 Figure 2. An intra-operative photograph demonstrating a 2.5cm ileal mass Figure 3 Figure 3. Intra-operative photograph showing the fish bone

An uncommon cause of lower gastrointestinal bleeding: a case report.

BackgroundThis report calls attention to severe gastrointestinal hemorrhage as a manifestation of small bowel carcinod tumor.PatientWe report a case of an adult in his 5th decade presenting with massive melena.InterventionsOn presentation the patient was tachycardic (pulse115/min), and hypotensive (BP 80/55 mmHg). His complete physical examination was unremarkable. Rectal exam showed frank blood. Nasogastric lavage produced greenish fluid with no blood. His hemoglobin was 8.1 gm/dl and hematocrit was 25.1%. Panendoscopy revealed an ileal bleeding mass. Interestingly a colonoscopy done 6 months earlier for anemia workup was normal. Emergent laparotomy revealed numerous smaller intraluminal nodules scattered throughout the small bowel.ResultsHistopathology revealed carcinoid tumor.

Image of the Month—Quiz Case

A 52-YEAR-OLD AFRICAN AMERICAN MAN with lactose intolerance, non–insulindependent diabetes mellitus, hypertension, and a virgin abdomen presented with a 6-week history of a 4.5-kg weight loss and a 3-month history of worsening, intermittent, colicky epigastric and periumbilical abdominal pain associated with nausea and vomiting. His pain was most intense postprandially but was relieved by vomiting. He had constipation relieved with laxatives but was passing flatus. A computed tomographic scan of the abdomen revealed a 4.5-cm ileal mass causing a high-grade partial small-bowel obstruction (Figure 1 and Figure 2). An exploratory laparotomy revealed a 5-cm mass in the proximal ileum. A 12.5-cm segment of proximal ileum was sent for pathological analysis.

Occult intestinal haemorrhage due to lipoma of the small bowel detected with the combined use of the new endoscopic techniques. A report of two cases

We report two unusual cases of occult intestinal bleeding due to lipoma of the small bowel. Both the patients underwent several inconclusive endoscopic and radiological procedures before the diagnosis of these lesions that was possible using video capsule endoscopy and double balloon enteroscopy. In the first case, the finding of capsule endoscopy was confirmed using enteroscopy, allowing us to diagnose the ileal mass. In the second and more recent case, we used double balloon enteroscopy for the further characterisation and management of the ileal lipoma. Lipoma is a very rare cause of intestinal bleeding and we describe the management and the outcome of our patients.

Asymptomatic ileal adenocarcinoma in the setting of undiagnosed Crohn’s disease

A 53-year old previously healthy male underwent a screening colonoscopy for detection of a potential colorectal neoplasm. The terminal ileum was intubated and a mass was noted. Examination of the colon was normal. The biopsy of the ileal mass was consistent with an adenocarcinoma arising from the terminal ileum. His father who had never been previously ill from gastrointestinal disease died of natural causes, but was found to have Crohn's disease postmortem. The patient underwent exploratory laparotomy and a right hemicolectomy with a 30 cm section of terminal ileum in continuity. Findings were consistent with ileal adenocarcinoma in the setting of Crohn's disease. The patient made an uneventful recovery. The pathology was stage 1 adenocarcinoma. This is a unique case in that on a screening colonoscopy, a favorable ileal adenocarcinoma was discovered in the setting of asymptomatic, undiagnosed ileal Crohn's disease in a patient whose father had Crohn's disease diagnosed postmortem.

Correlation Between Double Balloon Endoscopy and Capsule Endoscopy in Presumed Small Bowel Bleeding

Background: Capsule endoscopy (CE) is currently the favored modality for small bowel (SB) imaging, and is most commonly used to identify sources of SB bleeding. Double balloon endoscopy (DBE) is a new enteroscopy method which allows direct SB visualization and a range of therapeutic options that can benefit patients with SB bleeding. Aim: To correlate our DBE findings with CE findings in patients with presumed SB bleeding. Methods: Consecutive patients with presumed SB bleeding referred between 9/2004-6/2006 who had undergone CE by their referring physicians were selected from the Fox Chase DBE database. Results: 50 of 65 patients referred for presumed SB bleeding had a prior CE (77%). CE demonstrated a potential source in 31/50 (62%). Potential sources were: AVMs (18), erosions/ulcerations (2), polyps/masses (8), and non-specific or unspecified abnormalities (3). 53 antegrade DBEs in 47 patients and 25 retrograde DBE in 23 patients were performed (total 78 DBEs). Complete enteroscopy (requiring bidirectional DBE) was not specifically attempted in most patients but was achieved in 6 (12%). There was concordance between DBE and CE in 23 patients (46%): 15 patients (30%) had comparable abnormalities (+CE = +DBE) and 8 (16%) had no abnormality on either study (−CE = −DBE). There was discordance in 27 (54%): 11 patients (22%) had a potential source on DBE only (-CE,+DBE), 13 (26%) on CE only (+CE,-DBE), and 3 (6%) had incomparable abnormalities (+CE ≠ +DBE). Conclusions: Concordance between CE and DBE occurred in approximately half of patients with presumed SB bleeding. DBE identifies potentially significant abnormalities in some patients with unrevealing CE. Conversely, the DBE ‘miss’ rate of real CE findings is not yet known. Tabled 1 Concordance Abnormality +WCE = +DBE AVMs (12) Hamartoma (1) GIST (1) Polyp-no tissue diagnosis (1) −WCE = −DBE None (8) −WCE, +DBE AVMs (7) Lymphoma (1) Mesenteric lymphangiomatosis (1) Dieulafoy (1) Granulation polyp (1) +WCE, − DBE AVMs (6) Polyp/mass (3) Ulcerated lesions (2) Inflammation (1) Unspecified 'lesion' (1) +WCE ≠ + DBE Ileal mass≠phlebectasia (1) Polyp≠Erythema (1) Unspecified SB 'lesion'≠GAVE (1) Open table in a new tab

An Ileal Endometrioma: Of Carcinoids and Cadherin

A 38-year-old woman with history of prior adrenalectomy for Cushing’s syndrome presented with intermittent right lower quadrant (RLQ) abdominal pain, nausea, bloating, and non-bloody diarrhea for 2 months. Symptoms were not related to her menstrual periods. Examination revealed only an ill-defined mass in the RLQ. Investigations for infectious causes, inflammatory bowel disease, and carcinoid tumor were negative. Computed tomography (CT) demonstrated a terminal ileal mass with mesenteric stranding and dilatation of the proximal bowel. At laparotomy, a fibrotic, terminal ileal mass with matted adhesions involving the mesentery and retroperitoneum was resected. Histopathological examination identified multiple foci of endometriosis extending from the serosal surface into the mucosa of the terminal ileum. Immunostaining revealed E- and P-cadherin, but not N-cadherin immunopositivity. Mucosal involvement without cyclical menstrual symptoms and intestinal obstruction is an unusual presentation of intestinal endometriosis. Although the mechanism of endometriosis is not clear, the role of cell adhesion molecules such as cadherins has received attention. Increased expression of E- and P-cadherin and decreased N-cadherin expression in our patient demonstrates differential expression of these cadherins in endometriotic tissue. Future studies may investigate patterns of differential expression of these cadherins in a series of cases to elucidate the mechanisms of migration of endometriotic tissue.

Metachronic malignant transformation of small bowel and rectal endometriosis in the same patient

BackgroundMalignant transformation of intestinal endometriosis is a rare event with an unknown rate of incidence. Metachronous progression of endometriosis to adenocarcinoma from two distant intestinal foci happening in the same patient has not been previously reported.Case presentationWe describe a case of metachronic transformation of ileal and rectal endometriosis into an adenocarcinoma occurring in a 45-year-old female without macroscopic pelvic involvement of her endometriosis. First, a right colectomy was performed due to intestinal obstruction by an ileal mass. Pathological examination revealed an ileal endometrioid adenocarcinoma and contiguous microscopic endometriotic foci. Twenty months later, a rectal mass was discovered. An endoscopic biopsy revealed an adenocarcinoma. En bloc anterior rectum resection, hysterectomy and bilateral salpingectomy were performed. A second endometrioid adenocarcinoma arising from a focus of endometriosis within the wall of the rectum was diagnosed.ConclusionIntestinal endometriosis should be considered a premalignant condition in premenopausal women.

Vagal afferents are essential for maximal resection-induced intestinal adaptive growth in orally fed rats

Small bowel resection stimulates intestinal adaptive growth by a neuroendocrine process thought to involve both sympathetic and parasympathetic innervation and enterotrophic hormones such as glucagon-like peptide-2 (GLP-2). We investigated whether capsaicin-sensitive vagal afferent neurons are essential for maximal resection-induced intestinal growth. Rats received systemic or perivagal capsaicin or ganglionectomy before 70% midjejunoileal resection or transection and were fed orally or by total parenteral nutrition (TPN) for 7 days after surgery. Growth of residual bowel was assessed by changes in mucosal mass, protein, DNA, and histology. Both systemic and perivagal capsaicin significantly attenuated by 48-100% resection-induced increases in ileal mucosal mass, protein, and DNA in rats fed orally. Villus height was significantly reduced in resected rats given capsaicin compared with vehicle. Sucrase specific activity in jejunal mucosa was not significantly different; ileal mucosal sucrase specific activity was significantly increased by resection in capsaicin-treated rats. Capsaicin did not alter the 57% increase in ileal proglucagon mRNA or the 150% increase in plasma concentration of bioactive GLP-2 resulting from resection in orally fed rats. Ablation of spinal/splanchnic innervation by ganglionectomy failed to attenuate resection-induced adaptive growth. In TPN rats, capsaicin did not attenuate resection-induced mucosal growth. We conclude that vagal afferents are not essential for GLP-2 secretion when the ileum has direct contact with luminal nutrients after resection. In summary, vagal afferent neurons are essential for maximal resection-induced intestinal adaptation through a mechanism that appears to involve stimulation by luminal nutrients.

Bilateral asynchronous metastatic carcinoid tumor of the testis

Carcinoid tumor of the testis represents only 0.23% of all testicular malignancies. We report the first case of bilateral asynchronous carcinoid tumor of the testis with a primary site in the small bowel. A 49-year-old man presented with several months of painless enlargement of the left testis. Orchiectomy revealed carcinoid tumor. The patient presented to the emergency room 2 weeks later and was found to have small bowel obstruction due to an ileal mass. The resected mass was the primary source of the carcinoid tumor. Four years later, examination revealed carcinoid tumor in his remaining testis.

CLOSTRIDIUM PERFRINGENS BACTEREMIA IN A PATIENT WITH SMALL BOWEL LYMPHOMA AND MECKELʼS DIVERTICULUM

A 87 year old male with HTN, CVA, BPH, DJD, & appendectomy was admitted to the hospital with one day history of diarrhea, bilious vomiting & transient periumbilical discomfort. He denied fever, chills, NSAID use, unusual food intake or recent travel. He was on celecoxib, aspirin, & Hyzaar. The physical exam was unremarkable except for mild right lower quadrant abdominal discomfort without guarding or rebound. The lab evaluation showed mild leukocytosis, iron deficiency anemia, normal LDH & ESR. The blood culture was positive for C perfringens. The x-ray abdomen showed mildly distended small bowel loops. The CT scan of the abdomen showed small bowel wall thickening. The EGD & colonoscopy were negative. A CT scan 1 month later showed segmental thickening of the small bowel with enlarged mesenteric lymph nodes & omental infiltration suspicious for a neoplastic process. Laparotomy showed a mid ileal mass and a Meckel's diverticulum adherent to the umbilical stalk. A partial small bowel resection with primary anastomosis & Meckel's diverticulectomy were performed. The histopathology showed diffuse large B-cell lymphoma. A bone marrow biopsy was negative for lymphoma. The patient was referred to an Oncologist. Discussion: Small bowel lymphomas occur in about 9% of patients with GI tract non-Hodgkin's lymphomas (NHL). They account for up to 75% of primary GI tract lymphomas in Middle East & Mediterranean countries. The median age of patients with non immunoproliferative small intestinal disease (non-IPSID) lymphomas is 37 yrs with male preponderance. Common presenting symptoms are abdominal pain (75%), anorexia (41%), & weight loss (34%). GI bleeding is uncommon. The non-IPSID lymphomas are usually unifocal, appearing as ulcerated, protruding, or infiltrating mass in the distal small intestine. The B-cell intestinal lymphomas are uncommon and usually low-grade. The primary treatment is usually surgical resection followed by whole-abdominal irradiation and/or chemotherapy. The 1-year survival is up to 75%. There are few reported cases of lymphoma associated with Meckel's diverticulum especially within the Meckel's diverticulum. C perfringens bacteremia has not been reported as an initial presenting symptom of intestinal lymphoma. There are only two case reports of C perfringens bacteremia in patients with NHL undergoing chemotherapy. Both reported cases had colonic perforation.

The incorporation of whole grain into pelleted broiler chicken diets. II. Gastrointestinal and digesta characteristics

1. Pelleted diets, incorporating whole or ground wheat or barley in the pellets, were fed to broiler chickens and the performance, gastrointestinal development and digesta characteristics of those chickens recorded. 2. Body weight was similar with whole grain incorporation or enzyme application. Food conversion efficiency was improved by addition of enzyme to a full wheat diet. 3. Whole grain inclusion in pellets reduced proventriculus proportional mass and increased gizzard proportional mass with no apparent effects of exogenous feed enzyme addition. 4. Relative ileal mass was reduced by enzyme inclusion in a wheat diet and by inclusion of whole barley in the pellets. 5. Digesta viscosity was increased by whole wheat inclusion but reduced by enzyme inclusion irrespective of grain processing. Inclusion of 200 g/kg of barley did not alter viscosity of digesta beyond the duodenum. 6. Fresh excreta pH was higher with both cereals in the grower phase when whole grain was fed. On the barley diet, this was affected by enzyme addition, which created higher pH from a point earlier in the grower phase than when no enzyme was employed. 7. Evidence of a complex interaction between higher viscosity and pH being involved in differences in ileal relative mass was found through significant relationships being produced by enzyme use on the wheat diet alone.

Performance and ileal histomorphology of rats treated with humic acid preparations.

As humic acid (HA) substances have antiphlogistic, adsorptive, antitoxic and antimicrobial properties, we studied the possible effects of Farmagülatör, an organic HA preparation, on the rat performance, nutrient retention, ileal histomorphology and hydroxyproline (HP) content of the ileum in two experiments. In experiment 1, 48 male Wistar albino rats were allotted to three dietary treatments. Each was randomly assigned to four cages, each with four rats. The treatments consisted of a control diet (C) with no addition of Farmagülator Dry or Liquid, a treatment with addition of 2.5 g/kg Farmagülator Dry (FDry) and a control diet containing no FDry, but the rats had 3.5 ml/l Farmagülator Liquid in drinking water (FLiquid). The experiment lasted for 20 days. Changes in live weight were recorded at days 10 and 20 of the experiment. At the end of 20 days, all rats were killed to collect samples of intestinal tissues for the measurements of histological parameters. In experiment 2, 30 rats weaned at 21 days of age were divided into three groups, each with 10 rats, and individually caged in metabolism cages for 10 days. The above three treatments were randomly assigned to rats for 10 days to record body weight and feed intake. During the last 5 days, faecal outputs were collected to determine the dry matter and nitrogen retention. In experiment 1, FDry and FLiquid rats significantly (p<0.05) gained more live weight than the control rats. Improved weight gain with HA preparations was found to be highly associated with a high epithelial surface area as there were significantly (p<0.05) longer villi heights and crypt depths and increased HP contents of ileum in the HA treated rats compared with the control rats. Although the increased weight gain in FLiquid rats did not significantly (p>0.05) differ from the control rats in experiment 2 in contrast to the result in experiment 1, the FDry rats significantly (p < 0.05) gained more weight than the control rats. This was primarily found to be associated with significantly (p<0.05) increased feed intake and nitrogen retention in FDry rats compared with the control rats. It can be concluded that HA preparations, especially FDry, caused increased weight gain in rats as overall of two experiments. The improved weight gain only by FDry preparation was associated with increased ileal epithelial mass, increased feed intake, improved feed : gain ratio and increased nitrogen retention in rats.

The role of eicosanoids in the process of adaptation following massive bowel resection in the rat.

Long chain polyunsaturated fatty acids (LCPUFAs) such as arachidonic acid (AA) and eicosapentaenoic acid (EPA) stimulate intestinal adaptation. Prostaglandins also enhance intestinal adaptation. The purpose of this study was to determine by which eicosanoid pathway dietary arachidonic acid enhances intestinal adaptation. Cyclo-oxygenase or lipoxygenase were selectively inhibited to determine whether either of them enhanced or inhibited adaptation. Sixty Sprague-Dawley rats were divided into 2 groups, one receiving an 80% small bowel resection and the other receiving a sham operation. Rats were further divided into groups receiving either a placebo, a general lipoxygenase inhibitor (nordihydroguaiaretic acid [NDGA] at 40 mg/kg per day), or a cyclo-oxygenase-2 inhibitor (Etodolac at 3 mg/kg per day). Rats were pair-fed a diet containing 30% kcal from fat, primarily consisting of AA. After 14 days, mucosal mass, protein, DNA, and disaccharidase activity were measured in the remaining small intestine. There was a significant decrease in ileal mucosal mass in rats receiving Etodolac and a significant increase in mucosal mass in the duodenum in rats receiving NDGA (both p < .001). Mucosal DNA, protein, and disaccharidase data showed similar trends. These findings suggest that after small bowel resection, dietary arachidonic acid may facilitate the adaptation process by acting as a substrate for the synthesis of prostaglandins, and not through the derivatives of lipoxygenase such as leukotrienes or thromboxanes.

Minimal enteral nutrient requirements for intestinal growth in neonatal piglets: how much is enough?

Parenterally nourished preterm infants commonly receive minimal enteral feedings, the aim being to enhance intestinal function. Whether this regimen increases intestinal growth has not been established. Our objective was to determine the minimal enteral nutrient intakes necessary to stimulate and to normalize neonatal intestinal growth. Intestinal growth and cell proliferation were quantified in neonatal pigs given equal amounts of an elemental nutrient solution for 7 d. Different groups (n = 5-7 per group) received 0%, 10%, 20%, 40%, 60%, 80%, or 100% of total nutrient intake enterally, with the remainder given parenterally. In the jejunum, wet weight, protein mass, and villus height were significantly greater at enteral intakes >40%. Stimulation of ileal protein mass required a higher enteral intake (60%). In both segments, abrupt increases in DNA mass, crypt depth, ornithine decarboxylase activity, and crypt cells in S-phase occurred between enteral intakes of 40% and 60%. Circulating concentrations of glucagon-like peptide-2 and peptide YY, but not gastrin, increased significantly between enteral intakes of 40% and 60% and closely paralleled indexes of cell proliferation. The minimal enteral nutrient intake necessary to increase mucosal mass was 40% of total nutrient intake, whereas 60% enteral nutrition was necessary to sustain normal mucosal proliferation and growth. Our results imply that providing <40% of the total nutrient intake enterally does not have significant intestinal trophic effects.

Adaptation of cholesterol absorption after proximal resection of porcine small intestine.

Cholesterol absorption occurs primarily in the upper small intestine. Our aim was to assess absorption of cholesterol during ileal adaptation after proximal small intestinal resection. In vivo absorption and elimination of cholesterol, plasma cholesterol, cholesterol precursors, and plant sterols were related to intestinal morphology and transit 4 (n = 5), 8 (n = 5), and 14 (n = 5) weeks after a 75% proximal resection of porcine small intestine, and compared to preoperative (n = 5) and transected (n = 5) control animals. Fractional cholesterol absorption, the daily amount of cholesterol absorbed, plasma cholesterol, and plant sterol to cholesterol proportions were significantly (P < 0.05 or less) decreased, whereas fecal loss of cholesterol as neutral steroids, less so as bile acids, plasma cholesterol precursor proportions, and ileal mass and villus height were significantly increased (P < 0.05 or less) after 8 weeks of the resection. Cholesterol absorption efficiency, decreased by the resection, was gradually increased from 5.4 +/- 2.2 to 26.9 +/- 3.9% during the 14 postoperative weeks (P < 0.0001) simultaneously with a 46% increase in villus height compared with transection (P < 0.0001), but absorption remained still below control levels (80.4 +/- 2.5%, P < 0.0001). In resected and control animals, villus height correlated positively with cholesterol absorption efficiency (r = 0.85, P < 0.0001; r = 0.76, P = 0.01) and plasma plant sterol proportions (r = 0.94-0.95, P < 0.0001; r = 0.78-0.85, P < 0.008), respectively. In conclusion, after massive proximal small bowel resection, adaptation of intestinal cholesterol absorption efficiency occurs in the distal ileum closely parlleling villus hypertrophy.

Changes in intestinal alpha-methyl-D-glucoside uptake due to pregnancy and lactation in rats.

Uptake of alpha-methyl-D-glucoside, a nonmetabolizable glucose analogue, by everted intestinal sleeves was studied in virgin, pregnant and lactating rats. The animals showed an increase in jejunal and ileal tissue mass, mucosal mass, nominal surface area, and enzymatic activities. No changes were observed in the carrier affinity throughout the breeding stages. Nevertheless there was a significant increase in glucose carrier density (Vmax) per unit of length of jejunum and ileum in pregnant and lactating animals. Integrating the results obtained, and increased overall ability to transport hexoses by nonspecific adaptation can be observed in breeding stages.