Antiperistaltic Agents Research Articles

Esophagogastroduodenoscopy Quality Improvement and the Role of Topical Antiperistaltic Agents: A Systematic Review and Meta-Analysis.

Gastric cancer (GC) represents one of the most lethal forms of cancer.When identified at an early stage, conventional treatment can be curative. The key to identifying GC at an early stage ishigh-quality esophagogastroduodenoscopy (EGD). This has led to an increased focus on quality standards in EGD to improve the detection rates of early GC and its premalignant lesions (PMLs), such as atrophic gastritis. In Asia, the routine use of antiperistaltic (antispasmodic) agents is advocated to improve the quality of mucosal visualization during diagnostic EGD. The rationale is that the cessation of peristalsis should yield a more stable intragastric visual field to enhance the detection of early GC. Hyoscine and glucagon are commonly used as antiperistaltic agents. Both, however, must be given either intravenously or via intramuscular injection. They both also have potentially serious systemic side effects, which can limit their routine use, particularly in the elderly or co-morbid patients. As a result of these side effects, there is growing interest in using peppermint oil or L-menthol topically as anti-peristaltic agents. As these agents are applied topically (either via direct spraying during the EGD or consumed as a premedication before the EGD), they are associated with fewer adverse events than systemically applied agents. This study aimed to synthesize, for the first time, the available data on the use of topically applied anti-peristaltic agents to decrease or stop peristalsis during diagnostic EGDs.This study is a systematic review and meta-analysis of published randomized controlled trials. Its reporting is per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. This study was registered prospectively with the PROSPERO register, registration number CRD42024601488. This systematic review and meta-analysis encompassed five high-quality randomized controlled trials with a low risk of bias. All included studies were conducted in Asian countries between 2011 and 2022. They comprised 538 patients, with a mean age of 62.7. Four of the included studies look at topically applied L-menthol at 160 mg, while one study looked at the role of 160 mg of phloroglucinol administered as a 20 mL oral premedication liquid 15 minutes before the EGD. All included trials involved diagnostic EGDs and reported their primary outcomes using the same scoring systems. The primary outcome of interest for this study was the efficacy of the antiperistaltic agents at stopping peristalsis for the duration of a diagnostic EGD. We found an odds ratio of 4.22 with a 95% confidence interval ranging from 2.47 to 7.21, favoring the antiperistaltic agents in terms of attaining a peristalsis score of 1 after administration. This systematic review and meta-analysis represent the most up-to-date review on topical antiperistaltic agents during diagnostic EGD. We found that topical antiperistaltic agents effectively decrease or stop peristalsis during an EGD, and these effects persist for the duration of the EGD. Larger-scale studies willbe required to determine whether their routine usetranslates into increased detection rates of early GC and its PMLs.

A dynamic approach for MR T2-weighted pelvic imaging

T2-weighted 2D fast spin echo sequence serves as the standard sequence in
clinical pelvic MR imaging protocols. However, motion artifacts and blurring caused
by peristalsis present significant challenges. Patient preparation such as administering
antiperistaltic agents is often required before examination to reduce artifacts, which
discomfort the patients. This work introduce a novel dynamic approach for T2
weighted pelvic imaging to address peristalsis-induced motion issue without any patient
preparation.
Approach: A rapid dynamic data acquisition strategy with complementary sampling
trajectory is designed to enable highly undersampled motion-resistant data sampling,
and an unrolling method based on deep equilibrium model is leveraged to reconstruct
images from the dynamic sampled k-space data. Moreover, the fix-point convergence of
the equilibrium model ensures the stability of the reconstruction. The high acceleration
factor in each temporal phase, which is much higher than that in traditional static
imaging, has the potential to effectively freeze pelvic motion, thereby transforming
the imaging problem from conventional motion prevention or removal to motion
reconstruction.
Main results: Experiments on both retrospective and prospective data have
demonstrated the superior performance of the proposed dynamic approach in reducing
motion artifacts and accurately depicting structural details compared to standard static
imaging.
Significance: The proposed dynamic approach effectively captures motion states
through dynamic data acquisition and deep learning-based reconstruction, addressing
motion-related challenges in pelvic imaging.

Impact of deep learning-based reconstruction and anti-peristaltic agent on the image quality and diagnostic performance of magnetic resonance enterography comparing single breath-hold single-shot fast spin echo with and without anti-peristaltic agent.

While anti-peristaltic agents are beneficial for high quality magnetic resonance enterography (MRE), their use is constrained by potential side effects and increased examination complexity. We explored the potential of deep learning-based reconstruction (DLR) to compensate for the absence of anti-peristaltic agent, improve image quality and reduce artifact. This study aimed to evaluate the need for an anti-peristaltic agent in single breath-hold single-shot fast spin-echo (SSFSE) MRE and compare the image quality and artifacts between conventional reconstruction (CR) and DLR. We included 45 patients who underwent MRE for Crohn's disease between October 2021 and September 2022. Coronal SSFSE images without fat saturation were acquired before and after anti-peristaltic agent administration. Four sets of data were generated: SSFSE CR with and without an anti-peristaltic agent (CR-A and CR-NA, respectively) and SSFSE DLR with and without an anti-peristaltic agent (DLR-A and DLR-NA, respectively). Two radiologists independently reviewed the images for overall quality and artifacts, and compared the three images with DLR-A. The degree of distension and inflammatory parameters were scored on a 5-point scale in the jejunum and ileum, respectively. Signal-to-noise ratio (SNR) levels were calculated in superior mesenteric artery (SMA) and iliac bifurcation level. In terms of overall quality, DLR-NA demonstrated no significant difference compared to DLR-A, whereas CR-NA and CR-A demonstrated significant differences (P<0.05, both readers). Regarding overall artifacts, reader 1 rated DLR-A slightly better than DLR-NA in four cases and rated them as identical in 41 cases (P=0.046), whereas reader 2 demonstrated no difference. Bowel distension was significantly different in the jejunum (Reader 1: P=0.046; Reader 2: P=0.008) but not in the ileum. Agreements between the images (Reader 1: ĸ=0.73-1.00; Reader 2: ĸ=1.00) and readers (ĸ=0.66 for all comparisons) on inflammation were considered good to excellent. The sensitivity, specificity, and accuracy in diagnosing inflammation in the terminal ileum were the same among DLR-NA, DLR-A, CR-NA and CR-A (94.42%, 81.83%, and 89.69 %; and 83.33%, 90.91%, and 86.21% for Readers 1 and 2, respectively). In both SMA and iliac bifurcation levels, SNR of DLR images exhibited no significant differences. CR images showed significantly lower SNR compared with DLR images (P<0.001). SSFSE without anti-peristaltic agents demonstrated nearly equivalent quality to that with anti-peristaltic agents. Omitting anti-peristaltic agents before SSFSE and adding DLR could improve the scanning outcomes and reduce time.

State of the Art MR Enterography Technique.

Magnetic resonance enterography (MRE) is a well-established imaging technique that is commonly used for evaluating a variety of bowel diseases, most commonly inflammatory bowel disease which is increasing in prevalence. Inflammatory bowel disease is composed of 2 related, but distinct disease entities: Crohn disease (CD) and ulcerative colitis. In ulcerative colitis, inflammation is generally limited to the mucosa and invariably involves the rectum, and often the more proximal colon. CD is typified by transmural inflammation with skip lesions occurring anywhere from the mouth to anus, but characteristically involves the terminal ileum. The transmural involvement of CD may lead to debilitating ulceration and, ultimately, development of sinus tracts, which can be associated with abscesses and fistulae as extraenteric manifestations of the disease. Because much of the small bowel and extraenteric disease cannot be adequately assessed with conventional endoscopy, imaging plays a crucial role in initial diagnosis and follow-up. MRE does not use ionizing radiation which is important for these patients, many of which present earlier in life and may require multiple imaging examinations. In this article, we review the clinical indications, patient preparation, and optimal technique for MRE. We also discuss the role and proper selection of intravenous gadolinium-based contrast material, oral contrast material, and antiperistaltic agents, including pediatric considerations. Finally, we review the recommended and optional pulse sequence selection, including discussion of a "time-efficient" protocol, reviewing their utility, advantages, and limitations. Our hope is to aid the radiologist seeking to develop a robust MRE imaging program for the evaluation of bowel disease.

Recommendations for the diagnosis and treatment of Clostridioides difficile infection: An official clinical practice guideline of the Spanish Society of Chemotherapy (SEQ), Spanish Society of Internal Medicine (SEMI) and the working group of Postoperative Infection of the Spanish Society of Anesthesia and Reanimation (SEDAR).

ABSTRACTThis document gathers the opinion of a multidisciplinary forum of experts on different aspects of the diagnosis and treatment of Clostridioides difficile infection (CDI) in Spain. It has been structured around a series of questions that the attendees considered relevant and in which a consensus opinion was reached. The main messages were as follows:CDI should be suspected in patients older than 2 years of age in the presence of diarrhea, paralytic ileus and unexplained leukocytosis, even in the absence of classical risk factors. With a few exceptions, a single stool sample is sufficient for diagnosis, which can be sent to the laboratory with or without transportation media for enteropathogenic bacteria. In the absence of diarrhoea, rectal swabs may be valid. The microbiology laboratory should include C. difficile among the pathogens routinely searched in patients with diarrhoea.Laboratory tests in different order and sequence schemes include GDH detection, presence of toxins, molecular tests and toxigenic culture. Immediate determination of sensitivity to drugs such as vancomycin, metronidazole or fidaxomycin is not required. The evolution of toxin persistence is not a suitable test for follow up. Laboratory diagnosis of CDI should be rapid and results reported and interpreted to clinicians immediately.In addition to the basic support of all diarrheic episodes, CDI treatment requires the suppression of antiperistaltic agents, proton pump inhibitors and antibiotics, where possible. Oral vancomycin and fidaxomycin are the antibacterials of choice in treatment, intravenous metronidazole being restricted for patients in whom the presence of the above drugs in the intestinal lumen cannot be assured. Fecal material transplantation is the treatment of choice for patients with multiple recurrences but uncertainties persist regarding its standardization and safety. Bezlotoxumab is a monoclonal antibody to C. difficile toxin B that should be administered to patients at high risk of recurrence. Surgery is becoming less and less necessary and prevention with vaccines is under research. Probiotics have so far not been shown to be therapeutically or preventively effective. The therapeutic strategy should be based, rather than on the number of episodes, on the severity of the episodes and on their potential to recur. Some data point to the efficacy of oral vancomycin prophylaxis in patients who reccur CDI when systemic antibiotics are required again.

Prodromal Phase of Hemolytic Uremic Syndrome Related to Shiga Toxin-Producing Escherichia coli: The Wasted Time.

This study aimed to evaluate practice patterns during prodromal phase of hemolytic uremic syndrome related to Shiga toxin-producing Escherichia coli (STEC-HUS). Trajectories of children from first symptoms until STEC-HUS admitted consecutively at our center (period 2000-2017) were retrospectively reviewed. Early recommended practices include identification of STEC infections, antibiotics and antiperistaltic avoidance, and administration of anticipatory intravenous fluids; therefore, implementation and changes over time (before and after 2011) of such interventions were assessed. In addition, early management was correlated with acute disease outcomes. Of 172 patients, 98 (57%) had early consults, 75 of them visit the pediatric emergency department. Those seen with watery diarrhea (n = 74) were managed as outpatients, whereas 27 of the 45 assisted with bloody diarrhea were hospitalized for diagnosis other than STEC-HUS. Stool cultures were performed in 13.4% (23/172), 18% (31/172) received antibiotics, and 12.8% (22/172) received endovenous fluids; none received antiperistaltic agents. Shiga toxin-producing E. coli infection was proven in 4% (7/172) before HUS. Rate of cultured patients and treated with intravenous fluids remained unchanged over time (P = 0.13 and P = 0.48, respectively), whereas antibiotic prescription decreased from 42.8% to 16.6% (P = 0.005). Main acute outcomes (need for dialysis, pancreatic compromise, central nervous system involvement, and death) were similar (P > 0.05) regardless of whether they received antibiotics or intravenous fluids. During the diarrheal phase, 57% of patients consulted; three-quarters of them consulted to the pediatric emergency department. Shiga toxin-producing E. coli detection was poor, antibiotic use remained high, and anticipatory volume expansion was underused. These findings outline the critical need to improve the early management of STEC-HUS.

How to Improve Cannulation Rates During Endoscopic Retrograde Cholangiopancreatography

How to Improve Cannulation Rates During Endoscopic Retrograde Cholangiopancreatography

Risk factors, preemptive therapy, and antiperistaltic agents for Clostridium difficile infection in cancer patients

Clostridium difficile infection (CDI) is a serious complication of chemotherapy including high-dose regimens with autologous stem cell transplantation (ASCT). Antiperistaltic agents are contraindicated in CDI and preemptive CDI therapy is not recommended. We assessed the incidence, risk factors, and outcomes of CDI in patients with newly diagnosed multiple myeloma (MM) receiving similar antineoplastic therapy and supportive care including antiperistaltic agents and preemptive CDI antibiotics for significant diarrhea. A total of 303 consecutive MM patients (2004-2007) were enrolled in a protocol consisting of induction chemotherapy, tandem melphalan (MEL)-ASCT, and consolidation. Patients with grade 2-4 diarrhea were simultaneously tested for CDI, and initiated on antiperistaltic agents (loperamide) and preemptive anti-CDI therapy. Risk factors, including prior CDI and MM immunoglobulin (Ig) isotype, were evaluated. Multinomial logistic regression was used to compute the relative risk ratio (RRR) and 95% confidence intervals (CIs). There were 43 cases of CDI (14.2%) during 1529 chemotherapy courses (536 ASCT). IgA MM protected against CDI (RRR 0.35; 95% CI 0.13-0.93, P=0.04) whereas CDI during first induction markedly increased the risk of recurrence during second induction (RRR=10.94; 95% CI 1.90, 62.92, P=0.01) and following MEL-ASCT (RRR=6.63; 95% CI 1.51, 29.12, P=0.01). No CDI-related surgical intervention or death ensued despite use of antiperistaltic agents. CDI was not uncommon in cancer patients receiving chemotherapy. IgA myeloma appears to be protective. Concurrent antiperistaltic (loperamide) and preemptive CDI therapies were associated with excellent outcomes. Prior CDI history increased the risk for recurrence during successive chemotherapy courses.

Chronic calcium pyrophosphate crystal inflammatory arthritis induced by extreme hypomagnesemia in short bowel syndrome

BackgroundShort bowel syndrome (SBS) may induce a plethora of clinical symptoms ranging from underweight to nutrient-, vitamin- and electrolyte deficiencies. The objective of this case report is to illustrate how demanding the management of a 60 year old patient with SBS and recurrent joint attacks was for different medical disciplines.Case presentationThe patient with SBS presented with a body mass index of 16.5 kg/m2 after partial jejunoileal resection of the small intestine with a six year long history of recurrent pain attacks in multiple peripheral joints, chronic diarrhoea and food intolerances. Pain attacks occurred 4–5 times a week with a median consumption of 15 mg prednisone per day. The interdisciplinary workup after several gastroenterologic, rheumatologic, radiologic, psychiatric and orthopedic consultations is shown including successful treatment steps.Clinical diagnosis revealed no systemic inflammatory disease, but confirmed extreme hypomagnesemia (0.2 mmol/l) after reproducible pathological magnesium resorption tests as causative for chronic calcium pyrophosphate crystal inflammatory arthritis (pseudogout, chondrocalcinosis).Multidisciplinary treatment included application of colchicines, parenteral nutrition and magnesium substitution, antiperistaltic agents and avoidance of intolerant foods. Normalization of magnesium levels and a marked remission of joint attacks were achieved after six months with significant reduction of prednisone to 1.5 mg/day.ConclusionDespite the rarity of this condition, it is important to know that hypomagnesaemia may be associated with calcium pyrophosphate crystal inflammatory arthritis (chondrocalcinosis) and that SBS patients may be prone to develop extreme hypomagnesaemia causing recurrent joint attacks without systemic inflammation.

Hysterosalpingography in the workup of female infertility: indications, technique and diagnostic findings

ObjectivesTo evaluate the spectrum of diagnostic findings in hysterosalpingography (HSG) examinations performed at our institution between 2006–2010 and their prognostic significance for treatment decisions and fertility outcomes.MethodsPatients were filtered from our PACS. Pathological HSG studies were re-evaluated. Indications for referral, technical success and diagnostic findings were analysed. Pathological findings were correlated with further diagnostic workups, treatments and fertility outcomes.ResultsOf 411 HSG examinations, 226 (55 %) were normal, 94 (23 %) showed minor abnormalities and 5 (1.2 %) were not diagnostic. Eighty-six (21 %) examinations were pathological. Twenty-nine patients underwent subsequent laparoscopy, during which proximal tubal occlusion diagnosed at HSG was ruled out in 9/23 cases. Follow-up information was unavailable for 20 patients. Nineteen of 66 patients with follow-ups after pathological HSG had at least one subsequent successful pregnancy. Forty-one patients had no further treatment and no pregnancies.ConclusionsThe detection rate for pathologies at HSG was low (21 %). There was a high false-positive rate (39 %) for proximal tubal occlusion, most likely because of spasms, demonstrating the importance of delayed imaging after injection of antiperistaltic agents. HSG remains a valuable diagnostic tool. Our results, however, indicate that this technique should be more selectively indicated.Main Messages• Good acceptance of HSG by the patients. No complications with antibiotic prophylaxis.• Low detection rate (21 % pathological exams) for pathologies in our study.• High false-positive rate for proximal tubal occlusion.• This demonstrates the importance of waiting longer after injection of buscopan.• High pregnancy rate in pathological cases: Indication too broad or even a therapeutic effect of HSG?

MR enterography correlates highly with colonoscopy and histology for both distal ileal and colonic Crohn's disease in 310 patients

To evaluate the efficacy of MR enterography (MRE) in patients with known or suspected Crohn's disease without the use of anti-peristaltic pharmacologic agents compared to colonoscopy and histology. A retrospective review of 850 consecutive patients who underwent routine MRE to evaluate known or suspected Crohn's disease was performed. Of these, 310 patients also underwent colonoscopy with biopsy(s) within 90 days. The results of the MRE were compared to the colonoscopy and pathology reports to determine the presence or absence of disease in evaluable bowel segments. Individual imaging parameters (including wall thickening, enhancement, T2 signal, mesenteric vascular prominence and adenopathy) were also separately analyzed to determine their independent predictive value. In 310 patients, the overall sensitivity and specificity of MRE (using endoscopy as a gold standard) were 85% and 80% respectively (kappa=0.65). The sensitivity of MRE for detection of pathologically severe disease was 87% in the terminal ileum (TI) and 88% in the colon. In the subset of 162 patients who underwent colonoscopy within 30 days of MRE, the overall sensitivity remained 85% but the specificity increased to 85% (kappa=0.69). Wall thickening and abnormal enhancement were sensitive indicators of Crohn's disease (75% and 78%), while abnormal T2 signal, mesenteric vascular prominence and adenopathy were specific (86%, 91% and 93%). MRE compares favorably to colonoscopy for evaluation of known or suspected Crohn's disease noninvasively and without the exposure to ionizing radiation associated with CT enterography (CTE).

Detection of Crohn's disease: Comparison of CT and MR enterography without anti-peristaltic agents performed on the same day

ObjectiveTo directly compare CT enterography (CTE) and MR enterography (MRE) without antiperistaltic agents. Materials/methods26 patients referred for CTE underwent CTE immediately followed by MRE without use of an anti-peristaltic agent. Each study was evaluated on a 10 point scale for exam quality, level of diagnostic confidence, and presence of Crohn's disease. Kappa analysis was performed to determine the degree of agreement between the CTE and MRE of each patient. Results25 patients completed the MRE. The quality of the CTEs was judged as excellent by both readers (reader 1=average 9.5/10, reader 2=average 9.1/10). The quality of the MREs was ranked lower than the CTEs by both readers (reader 1=average 8.9/10, reader 2=average 7.2/10), which was statistically significant (p<0.05). The level of confidence in interpretation was not significantly different between CTE and MRE for reader 1 or 2 (p=0.3). There was substantial agreement between readers for the presence or absence of Crohn's disease on both CTE (kappa=0.75) and MRE (kappa=0.67). ConclusionMR enterography without anti-peristaltic agents results in high diagnostic confidence and excellent agreement for the presence of Crohn's disease.

MR Detection of Colonic Crohnʼs Disease Without Use of Colon Preparation or Anti-Peristaltic Agents

Purpose: Published studies of MR enterography (MRE) have focused on the detection of small bowel disease. We report the efficacy of MRE for the detection of colonic Crohn's disease without colon preparation or anti-peristaltic agent. Methods: 850 consecutive patients with known or suspected Crohn's disease underwent routine MRE without the use of pharmacologic bowel paralysis or colonic preparation. Of these, 310 patients also underwent endoscopy with biopsy(s). The sensitivity and specificity of the MRE for the detection of colonic Crohn's disease was retrospectively evaluated. Results: Of the 310 patients in our cohort, 143 patients underwent endoscopy and biopsy(s) within 30 days of the MRE. The sensitivity and specificity of MRE for the detection of colonic Crohn's disease (using pathology as a gold standard) was 67% and 97% respectively (kappa=0.69). The positive predictive value was 88% and the negative predictive value was 91%. Conclusion: MRE detects colonic involvement of Crohn's disease with a high specificity and negative predictive value. Colonic preparation and anti-peristaltic agents are not required for accurate diagnosis. MRE is currently not as sensitive in detecting colonic as it is in detecting small bowel Crohn's disease.

Magnetic Resonance Imaging of Uterine Malignancies

Magnetic Resonance Imaging (MRI) is the criterion standard in the assessment and staging of uterine cancer because of the high tissue contrast between glandular lining and inner and outer muscle layers of the uterine corpus and cervix on T2-weighted scans. It is also an essential tool in monitoring treatment response and in assessing disease recurrence in these patients. The key to a successful examination lies in good patient preparation, use of antiperistaltic agents, and a meticulous scanning technique. Endometrial carcinomas are the most common uterine malignancy, occurring in a primarily postmenopausal population. Dynamic contrast-enhanced scans may be required in addition to T2-weighted images to assess the presence of myometrial invasion in this age group. Cervical cancers occur in a younger population and are readily assessed with T2-weighted imaging. Use of an endovaginal receiver coil allows high spatial resolution imaging of the cervix, which is particularly useful when assessing patients for fertility-sparing procedures such as trachelectomy. Uterine sarcomas are 1% to 3% of all uterine malignancies and usually arise from a mixture of homologous and heterologous elements. Rarely, lymphoma, small cell carcinoma and metastatic deposits involve the uterus. This review summarizes the optimal scanning techniques for demonstrating uterine malignancy and discusses the role of imaging and the MRI appearances of uterine tumors.

CO2 as a distending medium for gastric and small bowel MRI: a feasibility study

This work evaluates carbon dioxide as a contrast medium for magnetic resonance imaging of the stomach and small bowel. Twelve healthy volunteers underwent rapid magnetic resonance imaging after oral administration of a carbon dioxide generating agent using a combination of breath-hold and interactive fluoroscopic imaging during breathing. Diagnostic-quality images were obtained in 100% of cases for the stomach and in 92, 75, 67 and 42% of cases for the duodenal segments 1-4, respectively. Visualisation of the jejunum and ileum proved unacceptable for clinical use and anti-peristaltic agents did not significantly influence the results. Further development of fast imaging and magnetic resonance interactive fluoroscopic methods may allow the use of carbon dioxide as a contrast medium for clinical imaging of the stomach and duodenum.

Clostridium difficile

Clostridium difficile

Percutaneous Jejunostomy

Direct percutaneous jejunostomy is considered in patients where percutaneous gastrostomy is not feasible (stomach removed or inaccessible). Percutaneous jejunostomy is more difficult than gastrostomy techniques. Direct jejunostomy is performed under fluoroscopic guidance, using a nasojejunal tube to distend the jejunum. The jejunal loop is punctured using a Cope suture anchor, under ultrasound guidance. Water-soluble contrast material is injected through the needle to document intralumenal position, and an anchor is inserted. With the guide wire in place, the track is dilated and a 10-F pigtail catheter inserted into the proximal jejunum. Fluoroscopy can also be used to aid puncture using dilute contrast material, if used via the nasogastric tube. Antiperistaltic agents can also be used to aid jejunal puncture. The cumulative procedure-related mortality from the three reported series in the literature is 2.4%, with minor complications occurring in 10 to 11%. Although jejunostomy is not performed frequently, this is a feasible procedure for interventional radiology.

Collagenous colitis

Collagenous colitis is associated with normal endoscopy examination and peculiar histopathological changes. The natural history and optimal treatment are not well defined. Our objectives were to analyze the symptomatology of collagenous colitis, determine the natural history, and response to treatment. All patients with collagenous colitis from 1978 to 1992 were studied. Demographic data, symptomatology, associated conditions, colonoscopic findings, and pathology specimens were reviewed. Clinical improvement was classified as none, partial, or complete. Nineteen patients were identified, mainly white females over age 50. Mean follow-up was 22.6 months. Symptom duration was 37 months (range 4 months to 15 years). Symptoms were intermittent diarrhea (19), with a predominant nocturnal component (13); abdominal pain (15); and mild weight loss and incontinence (8). Colonoscopy was normal in 12 patients. Segmental mucosal edema and loss of vasculature pattern were present in seven. Antiperistaltic agents were used in 17 patients with no improvement (15), partial resolution (1), and complete resolution (1). Eight nonresponders received sulfasalazine. Responses were none (6) or complete (2). Ten patients received steroids (10-20 mg/day). One failed to respond. Nine initially responded completely but two relapsed. Seven patients who did not respond to any type of treatment improved eventually, two partially and five completely. These patients were younger (54.3 vs 68.3 years, P = 0.04) and symptom duration was shorter (25.4 vs 44.5 months, P = 0.38) than the rest of the patients.(ABSTRACT TRUNCATED AT 250 WORDS)

OMR, a positive bowel contrast agent for abdominal and pelvic MR imaging: safety and imaging characteristics.

To determine the safety and imaging characteristics of OMR--an effervescent solution of ferric ammonium citrate--as a bowel contrast agent, magnetic resonance (MR) imaging at 1.5 T was performed in 29 volunteers. T1- and T2-weighted images of the upper abdomen and pelvis were obtained before and after oral administration of OMR at doses of 100-400 mg of iron in 300-600 mL of water. Respiratory-ordered phase encoding and presaturation pulses were used routinely for artifact suppression. All dose levels of OMR provided marking of the bowel by increasing intraluminal signal intensity; however, the degree and percentage of small bowel opacification appeared more prominent at higher dose levels of iron. Semisolid or watery bowel movements were noted in 31% of subjects, but no clinically important laboratory abnormalities were seen. OMR improved delineation of the head of the pancreas on T1-weighted images in 72% of subjects but was less useful in defining the body and tail. OMR is a safe and effective bowel contrast agent for MR imaging. Because artifacts due to movement of hyperintense bowel may degrade the images, OMR may be most useful on short TR/TE or fast imaging pulse sequences or when combined with antiperistaltic agents.

Gastroenterological emergencies in the tropics

Significant differences exist in the prevalence of most gastroenterological emergencies in tropical compared with temperate countries. Both ethnic and environmental (often clearly defined geographically) factors are relevant. The major oesophageal lesions which can present acutely in tropical countries are varices and carcinoma; bleeding and obstruction are important sequelae. Peptic ulcer disease (and its complications), often associated (not necessarily causally) with Helicobacter pylori infection, has marked geographical variations in incidence. Emergencies involving the small intestine are dominated by severe dehydration, and its sequelae, resulting from secretory diarrhoea, most notably cholera. However, enteritis necroticans (‘pig bel’ disease), paralytic ileus (sometimes caused by antiperistaltic agents) and obstruction (secondary to luminal helminths, volvulus and intussusception) are other important problems, especially in infants and children. Enteric fever is occasionally complicated by perforation and haemorrhage; the former (which is notoriously difficult to manage) is accompanied by significant mortality. Ileocaecal tuberculosis is a major cause of right iliac fossa pathology—sometimes associated with malabsorption; amoeboma is an important clinical differential diagnosis. The colon can be involved in invasive Entamoeba histolytica infection (which, like complicated enteric fever, is difficult to manage if the fulminant form, with perforation, ensues), shigellosis, volvulus and intussusception. Acute colonic dilatation occasionally follows Salmonella sp., Shigella sp., Campylobacter jejuni, Yersinia enterocolitica and rarely E. histolytica infections. Acute hepatocellular failure is a major cause of morbidity and mortality in the tropics and subtropics. It usually results from viral hepatitis (HBV, sometimes complicated by HDV, and HCV), but there is a long list of differential diagnoses. Hepatotoxicity resulting from herbs, chemotherapeutic agents or alcohol also occurs not infrequently. Chronic liver disease and its sequelae (often long-term results of viral hepatitis) are commonplace. Haematemesis and hepatocellular failure are usually very difficult to manage due to a lack of sophisticated support techniques in developing countries. Invasive hepatic amoebiasis usually responds well to medical management; however, spontaneous perforation can occur and the consequences of this are serious. Pyogenic liver abscess, although far less common than amoebic ‘abscess’, carries a bad prognosis whatever the method(s) of management. Hydatidosis and schistosomiasis also involve the liver, and helminthiases are important in the context of biliary tract disease. Gall stones are unusual in most tropical settings. Acute pancreatitis is overall unusual, but chronic calcific pancreatitis can present as an acute abdominal emergency.