Effect of somatostatin analog on water and electrolyte transport and transit time in human small bowel

ESPEN guideline on chronic intestinal failure in adults - Update 2023

BACKGROUND & AIMS

In 2016, ESPEN published the guideline for Chronic Intestinal Failure (CIF) in adults. An updated version of ESPEN guidelines on CIF due to benign disease in adults was devised in order to incorporate new evidence since the publication of the previous ESPEN guidelines.

METHODS

The grading system of the Scottish Intercollegiate Guidelines Network (SIGN) was used to grade the literature. Recommendations were graded according to the levels of evidence available as A (strong), B (conditional), 0 (weak) and Good practice points (GPP). The recommendations of the 2016 guideline (graded using the GRADE system) which were still valid, because no studies supporting an update were retrieved, were reworded and re-graded accordingly.

RESULTS

The recommendations of the 2016 guideline were reviewed, particularly focusing on definitions, and new chapters were included to devise recommendations on IF centers, chronic enterocutaneous fistulas, costs of IF, caring for CIF patients during pregnancy, transition of patients from pediatric to adult centers. The new guideline consist of 149 recommendations and 16 statements which were voted for consensus by ESPEN members, online in July 2022 and at conference during the annual Congress in September 2022. The Grade of recommendation is GPP for 96 (64.4%) of the recommendations, 0 for 29 (19.5%), B for 19 (12.7%), and A for only five (3.4%). The grade of consensus is "strong consensus" for 148 (99.3%) and "consensus" for one (0.7%) recommendation. The grade of consensus for the statements is "strong consensus" for 14 (87.5%) and "consensus" for two (12.5%).

CONCLUSIONS

It is confirmed that CIF management requires complex technologies, multidisciplinary and multiprofessional activity, and expertise to care for the underlying gastrointestinal disease and to provide HPN support. Most of the recommendations were graded as GPP, but almost all received a strong consensus.

The Long Road to the Development of Effective Therapies for the Short Gut Syndrome: A Personal Perspective

The ability to provide parenteral support represents a revolutionary change in medical therapy for patients with temporary and inadequate intestinal absorptive capacity or for patients with chronic intestinal failure due to digestive diseases. Nevertheless, due to the rarity of intestinal failure, a de facto policy of "discrimination by organ failure treatment" exists in many countries whereby this problem is under-recognized and under-treated. With the increasing recognition of the pathophysiological consequences of intestinal resection and the occurrence of new pro-adaptive treatments for patients suffering from short bowel syndrome, this review reflects on the history of developments in this area and discusses current practice and future directions of the field.

Octreotide reverses shock due to vasoactive intestinal peptide-secreting adrenal pheochromocytoma: A case report and review of literature

Vasoactive intestinal peptide-producing tumors (VIPoma) usually originate in the pancreas and are characterized by diarrhea, hypokalemia, and achlorhydria (WDHA syndrome). In adults, nonpancreatic VIPoma is very rare. Herein, we report an unusual case of VIP-producing pheochromocytoma marked by persistent shock, flushing, and watery diarrhea and high sensitivity to octreotide. A 53-year-old woman was hospitalized for sudden-onset hypertension with convulsions, which then rapidly evolved to persistent shock, flushing, and watery diarrhea. Abdominal computed tomography indicated a left adrenal mass, accompanied by bleeding; and marked elevations of both plasma catecholamine and VIP concentrations were documented via laboratory testing. Surprisingly, all clinical symptoms responded swiftly to octreotide treatment. Once surgically treated, hormonal levels normalized in this patient, and the clinical symptoms dissipated. Postoperative pathological and immunohistopathological studies confirmed a VIP-secreting pheochromocytoma with strong, diffuse positivity for somatostatin receptor type 2. During a 6-mo follow-up period, she seemed in good health and was symptom-free.

Update on medical treatment of small intestinal neuroendocrine tumors

INTRODUCTION

Small intestinal (SI) neuroendocrine tumors (NETs) are relatively rare tumors. Due to the lack of symptom or specific symptoms, SI-NETs are often diagnosed at an advanced stage, making therapy challenging. The management of patients with advanced stage SI-NETS requires a multidisciplinary approach that combines surgical and medical treatment including novel targeted molecular therapies.

AREAS COVERED

This article summarizes current strategies for the medical treatment of SI-NETS. Expert commentary: The treatment plan of advanced-stage SI-NETs should be tailored in a case-by-case manner with the adoption of a multidisciplinary approach that combines different treatment options, including biological targeted therapies. In particular, we believe that the identification of the optimal treatment sequence(s), correct treatment timing and the selection of patients eligible to different treatments need specific investigation in controlled clinical trials.

Somatostatin and Its Analogs in the Short Bowel Syndrome

The use of somatostatin to manage diarrhea associated with the short gut syndrome is impractical because of its need to be given by continuous infusion and a rebound effect on stool output with cessation of therapy. Octreotide has been used more successfully to control stool and electrolyte losses in patients with shortened gastrointestinal tracts. In published series and studies, all subjects appear to decrease stool losses, but clinical benefit for long-term use is not achieved for all patients. In the patients who do respond, the need for parenteral nutrition and intravenous hydration has been decreased or eliminated. The optimal dose is unclear, but many patients respond to 50-micrograms injections twice daily. Several investigations noted no additional beneficial effects with escalating dosages. Adverse effects include impairment of fat absorption, which may offset the therapeutic benefits of octreotide. The patients with the greatest response appear to have the least fat malabsorption. Other adverse effects noted when using octreotide for control of the short gut syndrome include pain associated with subcutaneous injection and abdominal complaints. Other potential concerns include the effect on gallstone formation in this high-risk population and intestinal adaptation.

Octreotide and enterocutaneous fistula closure in neonates and children

Enterocutaneous fistula and its conservative management still pose a challenge for the surgeon. The use of octreotide and somatostatin in neonates and children as adjunctive therapy in the conservative management of this condition, leads to major controversy regarding its efficacy. Therefore, we conducted an extensive literature review of published articles regarding the use of somatostatin and its analogues in the treatment of enterocutaneous fistula in neonates and children. Our review is then presented together with a case vignette and discusses the different practical aspects of the treatment with these drugs.

CONCLUSION

The major diversity in treatment regimens among published studies makes outcomes difficult to compare. However, given the results of the different cases reported in the literature and of our own experience, we suggest a possible beneficial effect of octreotide and somatostatin on closure of enterocutaneous fistula in these patients.

ESPEN guidelines on chronic intestinal failure in adults

BACKGROUND & AIMS

Chronic Intestinal Failure (CIF) is the long-lasting reduction of gut function, below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, such that intravenous supplementation is required to maintain health and/or growth. CIF is the rarest organ failure. Home parenteral nutrition (HPN) is the primary treatment for CIF. No guidelines (GLs) have been developed that address the global management of CIF. These GLs have been devised to generate comprehensive recommendations for safe and effective management of adult patients with CIF.

METHODS

The GLs were developed by the Home Artificial Nutrition & Chronic Intestinal Failure Special Interest Group of ESPEN. The GRADE system was used for assigning strength of evidence. Recommendations were discussed, submitted to Delphi rounds, and accepted in an online survey of ESPEN members.

RESULTS

The following topics were addressed: management of HPN; parenteral nutrition formulation; intestinal rehabilitation, medical therapies, and non-transplant surgery, for short bowel syndrome, chronic intestinal pseudo-obstruction, and radiation enteritis; intestinal transplantation; prevention/treatment of CVC-related infection, CVC-related occlusion/thrombosis; intestinal failure-associated liver disease, gallbladder sludge and stones, renal failure and metabolic bone disease. Literature search provided 623 full papers. Only 12% were controlled studies or meta-analyses. A total of 112 recommendations are given: grade of evidence, very low for 51%, low for 39%, moderate for 8%, and high for 2%; strength of recommendation: strong for 63%, weak for 37%.

CONCLUSIONS

CIF management requires complex technologies, multidisciplinary and multiprofessional activity, and expertise to care for both the underlying gastrointestinal disease and to provide HPN support. The rarity of the condition impairs the development of RCTs. As a consequence, most of the recommendations have a low or very low grade of evidence. However, two-thirds of the recommendations are considered strong. Specialized management and organization underpin these recommendations.

Octreotide prescribing patterns in the palliation of symptomatic inoperable malignant bowel obstruction patients at a single US academic hospital

BACKGROUND

Medical management is the cornerstone of malignant bowel obstruction (MBO) therapy and may include antisecretory agents such as octreotide. Currently, no data exist regarding octreotide prescribing patterns in US academic hospitals in the palliation of inoperable MBO. The aim of this study is to collect octreotide prescribing data to shape future prospective studies.

METHODS

This retrospective chart review evaluated inpatient inoperable MBO admissions at a single academic US hospital between 2008 and 2011. The prescribing primary service (medical vs. surgical), inpatient day initiated, average octreotide daily dose, cumulative octreotide dose, days receiving octreotide, length of stay (LOS), subject age, cancer stage, lines of chemotherapy, cancer type, and overall survival were analyzed utilizing a Wilcoxon rank sum test, Spearman rank correlation test, Kaplan-Meier curves, log rank test, and multiple linear regression analysis when appropriate.

RESULTS

A total of 767 patients received octreotide. A cancer diagnosis was documented in 134 patients and 37 of these (24 females and 13 males; mean age, 56.7 years) had a confirmed inoperable MBO. Statistical significance was not achieved for variables analyzed. However, octreotide prescribing trends were observed for several variables: the mean LOS was equivalent on both services (16.8 vs. 17 days), mean octreotide dose was higher on the medical service (201.2 μg vs. 119 μg surgical), cumulative octreotide dose was higher on the medical service (3,558 vs. 1,884 mcg), mean day of octreotide initiation was roughly equivalent (7.9 days medical vs. 8.8 days surgical), subjects on the medical service had a decreased overall survival, and earlier octreotide initiation (defined as <7 days) was associated with a decreased overall survival.

LIMITATION

The data were collected retrospectively, with a limited population distribution at a specific time.

CONCLUSIONS

These data possibly suggest that the MBO patients on the medical vs. surgical services are distinct patient populations. MBO patients on the medical service trended to receive higher cumulative doses and have a decreased overall survival compared with surgical patients. Consequently, future studies should possibly consider these distinct study groups.

Octreotide infusion for malignant duodenal obstruction in a 12-year-old girl with metastatic peripheral nerve sheath tumor

Malignant bowel obstruction is a common complication of some adult malignancies. In childhood cancer, malignant bowel obstruction is relatively rare. Octreotide, an analogue of the hormone somatostatin, has been shown to be an effective treatment for this condition in adults. However, explicit description of its use for this indication in children was not discovered in the pediatric literature by this group of authors. The following report is that of a 12-year-old female who had copious bilious emesis secondary to malignant obstruction of the distal duodenum, which abated after treatment with a continuous intravenous octreotide infusion.

Gastrointestinal neuroendocrine tumors

Gastrointestinal neuroendocrine tumors (GI-NETs) are a genetically diverse group of malignancies that sometimes produce peptides causing characteristic hormonal syndromes. NETs can be clinically symptomatic (functioning) or silent (non-functioning); both types frequently synthesize more than one peptide, although often these are not associated with specific syndromes. Based on data from various sources the incidence and prevalence of GI-NETs is increasing. Surgery is the only possible curative approach and so represents the traditional first-line therapy. However, as most patients with NETs are diagnosed once metastases have occurred, curative surgery is generally not possible. Patients therefore require medical management with the aim of relieving symptoms and suppressing tumor growth and spread. Somatostatin analogues can improve the symptoms of carcinoid syndrome and stabilize tumor growth (PROMID study) in many patients. An antiproliferative effect can also be achieved with the m-TOR inhibitor everolimus, alone or in combination with octreotide LAR. The vascular endothelial growth factor inhibitor sunitinib has demonstrated antitumor effects in pancreatic NETs. Pasireotide, the multi-receptor targeted somatostatin analogue, has the potential to be an effective therapy for de novo or octreotide-refractory carcinoid syndrome. Peptide receptor radiotherapy with yttrium 90-DOTATOC or lutetium 177-DOTATE are also new interesting treatment options for NETs.

Octreotide acetate is efficacious and safe in children for treating diarrhea due to chemotherapy but not acute graft versus host disease

BACKGROUND

The Common Toxicity Criteria of the National Cancer Institute evaluates diarrhea as an adverse event of chemotherapy administration. Acute graft versus host disease (aGVHD) causes diarrhea in allogeneic hematopoietic stem cell transplant patients. Guidelines for treating grade 3 and 4 chemotherapy induced diarrhea (CID) include octreotide acetate, a somatostatin analogue. These recommendations are based on adult octreotide trials. Data on octreotide use for treatment of CID in pediatric oncology patients are limited. This study evaluated the efficacy and safety of octreotide in the treatment of CID or aGVHD induced diarrhea in pediatric patients.

METHODS

This is a retrospective review of 34 patients of average age 6 years who received octreotide between 1994 and 2008 for treatment of CID or aGVHD induced diarrhea.

RESULTS

Thirty-eight courses of intravenous octreotide were administered. A complete response was achieved during 25/27 (92%) CID and 5/11 (45%) aGVHD induced diarrhea courses. A partial response was achieved during 4/38 courses, all in the aGVHD induced diarrhea group. No response was observed for 3 of the aGVHD induced diarrhea courses and 1 for the CID course. Octreotide was initiated at 2 mcg/kg/day and increased to a maximum of 9 mcg/kg/day. The mean total duration of treatment was 9 days. Common adverse effects observed were hyperglycemia, hyberbilirubinemia, nausea/vomiting, and abdominal cramping.

CONCLUSION

In pediatric patients, octreotide exhibits 92% efficacy in treating CID and 45% efficacy in aGVHD induced diarrhea. Further studies to better characterize the starting dose and dose escalation algorithm for treating CID in children are required.

Management of neuroendocrine tumors: current and future therapies

Neuroendocrine tumors (NETs) are a genetically diverse group of malignancies that sometimes produce peptides that cause characteristic hormonal syndromes. NETs can be clinically symptomatic (functioning) or silent (nonfunctioning); both types frequently synthesize more than one peptide, although often these are not associated with specific syndromes. Based on data from various sources, the incidence and prevalence of NETs is increasing. The primary treatment goal for patients with NETs is curative, with symptom control and the limitation of tumor progression as secondary goals. Surgery is the only possible curative approach and so represents the traditional first-line therapy. However, as most patients with NETs are diagnosed once metastases have occurred, curative surgery is generally not possible. Patients therefore require chronic postoperative medical management with the aim of relieving symptoms and, in recent years, suppressing tumor growth and spread. Somatostatin analogues, such as octreotide long-acting repeatable (LAR), can improve the symptoms of carcinoid syndrome and stabilize tumor growth in many patients. Results from the placebo-controlled, double-blind, prospective randomized study on the effect of octreotide LAR in the control of tumor growth in patients with metastatic neuroendocrine midgut tumors (PROMID study) demonstrate that octreotide LAR 30 mg is an effective antiproliferative treatment in patients with newly diagnosed, functionally active or inactive, well-differentiated metastatic midgut NETs. An antiproliferative effect can also be achieved with everolimus, and combination therapy with octreotide LAR has shown synergistic antiproliferative activity. Sunitinib, a tyrosine kinase inhibitor, is active in pancreatic NETs. In the future, pasireotide, the multireceptor targeted somatostatin analogue, has the potential to be an effective therapy for de novo or octreotide-refractory carcinoid syndrome and for inhibiting tumor cell proliferation. Peptide receptor radiotherapy with ⁹⁰Yttrium-DOTATOC or ¹⁷⁷Lutetium-DOTATE is also a new interesting treatment option for NETs.

From somatostatin to octreotide LAR: evolution of a somatostatin analogue

BACKGROUND

Acromegaly is characterized by overproduction of growth hormone (GH) by the pituitary gland. GH stimulates the synthesis of insulin-like growth factor-I (IGF-I), and the somatic growth and metabolic dysfunction that characterize acromegaly are a consequence of elevated GH and IGF-I levels. Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are rare, slow-growing neoplasms that have usually metastasized by the time of diagnosis. The majority of GEP-NETs are carcinoid tumors whose syndrome is caused by the hypersecretion of biogenic amines, peptides and polypeptides responsible for the principal symptoms of diarrhea and flushing.

METHODS

The MEDLINE and EMBASE databases were searched for preclinical and clinical studies of octreotide (Sandostatin* ), a potent synthetic somatostatin analogue, in patients with acromegaly or GEP-NETs.

OBJECTIVE

This article reviews the 20 years of clinical experience with octreotide and the impact it has made in patients with acromegaly or GEP-NETs.

RESULTS

Octreotide has proven to be an essential component in the management strategy of acromegaly and GEP-NETs over the past 20 years. The multiple beneficial effects of octreotide throughout the body, combined with its established safety profile (the most common adverse effects are injection-site pain and gastrointestinal events), have made it an appealing option for clinicians. The advent of the long-acting release (LAR) formulation of octreotide provided additional benefits to patients through monthly administration, while maintaining the efficacy and tolerability profile of the daily subcutaneous formulation.

CONCLUSIONS

Octreotide is a potent synthetic somatostatin analogue that has become the mainstay of medical therapy for tumor control in neuroendocrine disorders such as acromegaly and GEP-NETs. The development of octreotide LAR offered a further advancement; less frequent dosing provided valuable benefits in quality of life to patients, with equivalent efficacy and tolerability. Moreover, recent results from the PROMID study have confirmed the antiproliferative effect of octreotide LAR in patients with well-differentiated metastatic GEP-NETs of the midgut. New therapeutic uses of octreotide are currently under investigation in a variety of clinical settings.

Assessment of splanchnic blood flow using magnetic resonance imaging

BACKGROUND AND AIMS

The splanchnic circulation has an important function in the body under both physiological and pathophysiological conditions. Despite its importance, no reliable noninvasive procedures for estimating splanchnic circulation have been established. The aim of this study was to evaluate MRI as a tool for assessing intra-abdominal blood flows of the aorta, portal vein (VPO) and the major intestinal and hepatic vessels.

METHODS

In nine healthy volunteers, the proximal aorta (AOP) and distal abdominal aorta (AOD), superior mesenteric artery (SAM), celiac trunk (CTR), hepatic arteries (common and proper hepatic arteries, AHC and AHP, respectively), and VPO were localized on contrast-enhanced magnetic resonance angiography images. Volumetric flow was measured using a two-dimensional cine echocardiogram-gated phase contrast technique. Measurements were taken before and 30 min after continuous intravenous infusion of somatostatin (250 microg/h) and were independently evaluated by two investigators.

RESULTS

Blood flow measured by MRI in the VPO, SAM, AOP, AHP, and CTR significantly decreased after drug infusion. Flows in the AOD and AHC showed a tendency to decrease (P>0.05). Interrater agreement on flows in MRI was very good for large vessels (VPO, AOP, and AOD), with a concordance correlation coefficient of 0.94, as well as for smaller vessels such as the CTR, AHC, AHP, and SAM (concordance correlation coefficient =0.78).

CONCLUSION

Somatostatin-induced blood flow changes in the splanchnic region were reliably detected by MRI. MRI may be useful for the noninvasive assessment of blood flow changes in the splanchnic region.

Octreotide in the management of chemoradiotherapy-induced diarrhea refractory to loperamide in patients with rectal carcinoma

OBJECTIVE

To evaluate the efficacy of octreotide in the treatment of chemoradiotherapy (CRT)-induced diarrhea (CRTID) refractory to conventional loperamide treatment in this pilot study.

METHODS

Forty-two rectal carcinoma (T(3-4)N(0-2)M(0)) patients with grade 2 or 3 diarrhea refractory to loperamide were enrolled to receive octreotide. Eligible patients were treated with pelvic radiotherapy combined with bolus 5- fluorouracil CRT. Octreotide was administered subcutaneously, 150 microg three times daily, for 5 consecutive days. Only complete resolution of diarrhea was considered as therapeutic success.

RESULTS

Diarrhea mainly occurred in the first 4 weeks of CRT (83.3%) and completely resolved in 34 patients (80.9%) following octreotide administration. Mean time to response was 2.7 days: 27 patients (64%) responded during the first 3 days, and the remaining 7 (17%) on days 4 and 5. No significant side effect was reported. Eight patients (19.1%) with refractory diarrhea were hospitalized for additional treatment. No treatment delay was reported in complete responders, whereas an average 7.7-day delay was observed in refractory patients. Antidiarrheal treatment was administered on an outpatient basis in the response group, whereas refractory patients were hospitalized for an average of 8.8 days.

CONCLUSION

Daily subcutaneous octreotide administration (150 microg t.i.d.) for 5 days is apparently an effective, tolerable treatment modality for concurrent CRTID refractory to loperamide.

Effect of long-term treatment with octreotide on rectal sensitivity in patients with non-constipated irritable bowel syndrome

BACKGROUND

Acute administration of octreotide reduces visceral perception and therefore has been suggested as potential treatment for irritable bowel syndrome. Whether prolonged treatment with octreotide also reduces visceral sensitivity and improves gastrointestinal symptoms remains, however, unknown.

AIM

To investigate the effect of a slow release preparation of octreotide on rectal sensitivity and symptoms in irritable bowel syndrome patients.

METHODS

Forty-six non-constipated irritable bowel syndrome patients (52% female, 19-63 years) participated. Before and after 8 weeks of treatment with octreotide (Sandostatin LAR 20 mg i.m.) or placebo, patients underwent a barostat study to assess the rectal sensitivity. During a 2-week run-in period and treatment, abdominal pain, defecation frequency, consistency and symptom relief were scored weekly.

RESULTS

Octreotide, but not placebo, significantly increased the threshold for first sensation. Thresholds for urge to defecate and discomfort/pain and rectal compliance were not altered by either treatment. Octreotide improved stool consistency compared with placebo (loose stools after eight weeks: octreotide: 52%, placebo: 81%, P < 0.05). In contrast, abdominal pain and defecation frequency were not affected.

CONCLUSIONS

Although the threshold of first rectal sensation increased and stool consistency improved, long-term treatment with octreotide, at least at the current dose used, has no visceral analgesic effect and fails to improve irritable bowel syndrome symptoms.

Diagnosis and treatment of VIPoma in a female patient

We report a case of VIPoma in an 83-year-old female patient, who presented with frequent and excessive diarrhoea, muscle weakness, and severe hypokalaemia. Abdominal computed tomography (CT) revealed a 4x6 cm mass in the body of the pancreas. Laboratory analysis showed elevated levels of both vasoactive intestinal polypeptide (VIP; 153 pmol/l) and pancreatic polypeptide (161 pmol/l). In view of the patient's age, physical condition, and tumour size, surgical resection was not performed. The patient was treated with a long-acting octreotide, after which her symptoms diminished. After 24 months of follow-up, the patient remained in good physical condition without any further serious gastrointestinal symptoms. The VIPoma syndrome is caused by a neuroendocrine tumour, usually located in the pancreas, which secretes VIP, causing severe diarrhoea, dehydration and hypokalaemia. Treatment options include resection of the tumour, chemotherapy or the reduction of symptoms with somatostatin analogues. We provide an overview of the incidence, pathophysiology, diagnosis, treatment strategies, and prognosis of this rare syndrome.

Effect of octreotide on fluid absorption and secretion by the normal human jejunum and ileum in vivo

BACKGROUND

We hypothesized that part of the non-specific antidiarrhoeal effect of octreotide is mediated by a proabsorptive or antisecretory effect on small intestinal active electrolyte transport.

METHODS

To measure the effect of octreotide on net absorption, the jejunum and ileum of normal human subjects were perfused with a balanced electrolyte solution; to measure the effect of octreotide on normal active chloride secretion, the jejunum was perfused with a bicarbonate-free solution.

RESULTS

During perfusion of a balanced electrolyte solution, octreotide increased basal net fluid absorption in the jejunum and ileum by about 40 mL/h per 30 cm. In the jejunum, octreotide markedly inhibited basal and sham feeding-stimulated active chloride secretion and inhibited water secretion by 28 and 51 mL/h per 30 cm, respectively.

CONCLUSIONS

Octreotide causes an increase in the net epithelial cell absorption rate of a balanced electrolyte solution in the normal jejunum and ileum. In the jejunum, this proabsorptive effect is mediated mainly by the reduction of normal active electrolyte secretion, rather than by stimulation of normal active electrolyte absorption. These results support the hypothesis that part of the antidiarrhoeal action of octreotide is due to its effects on active electrolyte transport mechanisms by normal epithelial cells of the small intestine.

Systematic review: the use of somatostatin or octreotide in refractory diarrhoea

BACKGROUND

Somatostatin and octreotide have multiple effects which make them ideal for treating diarrhoea of different aetiologies. Their use in a variety of conditions with refractory diarrhoea, however, is based on a limited number of studies.

AIM

We undertook a systematic review of the available English literature to maximize an evidence-based approach to the treatment of refractory diarrhoea. We tested the hypothesis that efficacy is independent of aetiology.

METHODS AND RESULTS

A Medline and individual article search from 1965 to 2000 was undertaken on the use of somatostatin and octreotide in diarrhoea. All reports containing at least five subjects were included. The percentage response in case series and randomized controlled trials was compared, and a meta-analysis of randomized controlled trials where patient level data were provided was carried out. There were 30 publications found (18 case series, 12 randomized controlled trials). The response percentage was 73% overall in case series and 64% in randomized controlled trials (not significant). A meta-analysis of nine randomized controlled trials revealed significant heterogeneity despite an overall relative risk of 0.5 (95% confidence interval, 0.27-0.91). Subgroup analysis of the largest aetiological groups showed that acquired immunodeficiency syndrome studies were homogeneous, but somatostatin and octreotide were less effective. Post-chemotherapy studies remained heterogeneous and somatostatin and octreotide were highly effective.

CONCLUSIONS

While this review strengthens the consensus guidelines on the use of somatostatin and octreotide for refractory diarrhoea, evidence-based support requires additional studies.

An open trial of octreotide long-acting release in the management of short bowel syndrome

OBJECTIVES

The aim of this study was to assess the effects of the long-acting release (LAR) depot octreotide preparation Sandostatin LAR Depot on stool water and electrolyte losses, fecal fat excretion, and GI transit in patients with short bowel syndrome.

METHODS

We performed a 15-wk, prospective, open-label study of intramuscular (i.m.) Sandostatin LAR Depot, 20 mg, at 0, 3, 7, and 11 wk. Balance studies were performed before and at the end of the 15-wk study. Baseline and posttreatment measurements of body weight, stool fat, sodium and potassium, and gastric and small bowel transit of a radiolabeled egg meal were compared by paired analysis.

RESULTS

We studied eight patients with short bowel syndrome (five women and three men; mean age 52 yr, range 37-72 yr) who had been TPN dependent for a mean of 11.8 yr (range 1.5-22 yr). The underlying diagnoses were Crohn's disease (n = 6), intestinal ischemia (n = 1), and resection for carcinoid tumor (n = 1). Treatment with Sandostatin LAR Depot significantly increased small bowel transit time (p = 0.03). Changes in body weight, urine volume, stool weight, fecal fat excretion, stool sodium and potassium excretion, or gastric emptying rate were highly variable, and no overall significance was observed.

CONCLUSIONS

Sandostatin LAR Depot for 15 wk significantly prolonged small bowel transit time. Body weight and stool parameters in response to Sandostatin LAR Depot treatment needs to be assessed further in multicenter studies assessing dose, frequency of administration, and a larger sample size.

Octreotide in the treatment of severe chemotherapy-induced diarrhea

BACKGROUND

Chemotherapy-induced diarrhea (CID) is a common side effect of a number of chemotherapeutic agents. Conventional therapy for severe CID with opioids or loperamide is moderately effective. A prospective trial was conducted using octreotide acetate for treatment of severe CID refractory to loperamide.

PATIENTS AND METHODS

Thirty-two patients with grade 2 and 3 CID refractory to loperamide were treated with octreotide at a dosage of 100 microg subcutaneously 3x/day for three days followed by 50 microg 3x/day for three days. Previous chemotherapy consisted of regimens containing fluorouracil, leucovorin, CPT-11, cyclophosphamide, methotrexate and cisplatin. Primary tumors were colorectal (n = 23), gastric (n = 3), and other cancers (n = 6).

RESULTS

Complete resolution of diarrhea was obtained in 30 of 32 patients (94%); 5 within 24 hours, 14 within 48 hours, and 11 within 72 hours of treatment. Nineteen patients were treated as outpatients. Thirteen were hospitalized for a median of three days. Response was unaffected by age, gender, performance status, previous chemotherapy or primary tumor site. No side effects related to octreotide were observed.

CONCLUSIONS

Octreotide 100 microg subcutaneously 3x/day for three days is an effective, safe treatment for CID given primarily or as a second-line therapy after loperamide failure.

Management of cancer treatment-related diarrhea. Issues and therapeutic strategies

The cancer treatment-related diarrhea caused by acute graft-versus-host disease (GVHD) and chemotherapeutic agents, particularly fluoropyrimidines and irinotecan, significantly affects patient morbidity and mortality. The mechanisms causing cancer treatment-related diarrhea are not fully understood, but histopathologic evidence points to a multifactorial process that causes an absorptive and secretory imbalance in the small bowel. Cancer treatment-related diarrhea could be life-threatening, yet assessment and treatment are not currently standardized. Several clinicians participated in a closed roundtable meeting to review the mechanisms of chemotherapy-induced diarrhea (CID) and GVHD-induced diarrhea, management issues in cancer treatment-induced diarrhea, and pharmacologic approaches to treatment. The meeting produced a proposal for new treatment guidelines and an algorithm, which include the use of octreotide for the management of CID- and GVHD-induced diarrhea. The development of diarrhea assessment guidelines that expand on the current National Cancer Institute criteria and allow for better patient management was also proposed.

Octreotide does not prevent diarrhea in patients treated with weekly 5-fluorouracil plus high-dose leucovorin

The somatostatin analog, octreotide, is effective in treating diarrhea associated with cancer chemotherapy. This study was undertaken to determine whether octreotide could be used as prophylaxis against chemotherapy-induced diarrhea and, thereby, permit increased dose intensity. Adult cancer patients were treated with a standard regimen of intravenous 5-fluorouracil (5-FU) (600 mg/m2) plus leucovorin (LV) (500 mg/m2) weekly x 6 weeks. In addition, 150 microg of octreotide was administered subcutaneously twice daily, beginning on the first day of chemotherapy and continuing for 43 days. Escalation of 5-FU was planned for successive cohorts based upon toxicity. Eleven patients were treated at the initial 5-FU dose level. In 10 evaluable patients, dose-limiting toxicities were diarrhea (two patients), fatigue (one patient), and hyperbilirubinemia (one patient). Diarrhea was experienced by six of 10 patients, and only three patients were able to receive six weekly chemotherapy treatments without dose reduction or delay. At a dose of 150 microg twice daily, octreotide did not prevent diarrhea associated with 5-FU plus LV, and 5-FU dose escalation was not possible. While octreotide is successful in the treatment of 5-FU-induced diarrhea, we were unable to demonstrate a role in toxicity prophylaxis.

Efficacy of octreotide in diarrhoea due to Vibrio cholerae: a randomized, controlled trial

Although octreotide, a long-acting analogue of somatostatin, is currently used in the treatment of chronic secretory diarrhoea due to various causes, its role in the management of acute secretory diarrhoea is not well established. In the present study, therefore, the therapeutic value of octreotide in the management of cholera, a classical example of acute secretory diarrhoea, was investigated. During an outbreak of cholera, patients admitted with acute secretory diarrhoea of < or = 24 h duration and a purging rate > 100 ml/h were enrolled on the study and randomly assigned to octreotide (N = 17) and control (N = 16) groups. All 33 patients received intravenous fluid replacement and antibiotic treatment (200 mg ofloxacin twice daily for 3 days, by mouth). Each patient in the octreotide group was also given a subcutaneous injection containing 100 micrograms octreotide every 8 h for a maximum of six doses. The stool output of each patient was recorded every hour until there had been none for an hour, which was taken as the endpoint. Mean (S.D.) total stool output was lower [6.56 (3.7) v. 9.7 (6.5) litres] and the mean (S.D.) duration of diarrhoea after admission was shorter [32.9 (15.6) v. 47.8 (22.3); P < 0.05] in the octreotide group than in the control group. However, as both groups generally had similar purging rates, the higher volume of stools from the control group was simply the result of the longer period of diarrhoea in this group. Octreotide therefore only decreased the duration of diarrhoea in the cholera patients.

Roles of gall bladder emptying and intestinal transit in the pathogenesis of octreotide induced gall bladder stones

BACKGROUND

Octreotide treatment of acromegalic patients increases the % deoxycholic acid conjugates and the cholesterol saturation of gall bladder bile, and induces gall stone formation.

AIMS

To study the roles of gall bladder emptying and intestinal transit in these phenomena.

METHODS AND PATIENTS

Gall bladder emptying and mouth to caecum transit was measured in (a) control subjects and acromegalic patients given saline or 50 micrograms of octreotide, and (b) acromegalic patients taking long term octreotide. In the second group, large bowel transit was also measured.

RESULTS

A single dose of octreotide inhibited meal stimulated gall bladder emptying, the ejection fraction falling from mean (SEM) 66.0 (2.3)% to 7.0 (5.3)% in controls (p < 0.001); from 72.5 (2.1) to 16.6 (5.1)% in untreated acromegalic patients (p < 0.001), and to 30.4 (9.5)% in acromegalic patients taking long term octreotide (p < 0.001 v untreated acromegalic group). Octreotide prolonged mouth to caecum transit time, from 112 (15) min to 237 (13) min in controls (p < 0.001), from 170 (13) min to 282 (11) min in untreated acromegalic patients (p < 0.001), and to 247 (10) min in acromegalic patients taking long term octreotide (p < 0.001 v untreated acromegalic patients). The mean large bowel transit in octreotide untreated compared with treated acromegalic patients remained unchanged (40 (6) h v 47 (6) h).

CONCLUSIONS

Prolongation of intestinal transit and impaired gall bladder emptying may contribute to lithogenic changes in bile composition and gall stone formation in patients receiving long term octreotide.

Octreotide for treatment of postoperative alimentary tract fistulas

Eighteen patients with postoperative fistulas of the gastrointestinal tract were treated with the somatostatin analog octreotide between November 1989 and November 1992. Fourteen patients had enterocutaneous fistulas: seven from the duodenum and seven from the ileum. Another three patients had pancreatic fistulas, and one patient had a biliary fistula. Within 24 hours of octreotide treatment, a mean reduction of 52% in the intestinal fistulas' output, 40% in the pancreatic fistulas, and 30% in the biliary fistula was noted. In the intestinal fistulas group the closure rate was 72% after a mean of 11 days. Early closure (mean 6 days) was achieved in all three pancreatic fistulas. In the patient with the biliary fistula a 30% reduction was observed twice following the administration of octreotide, and an increase occurred when it was withheld. The reduction rate of the secretions in high-output intestinal fistulas (> 500 ml/day) was higher than in the low-output fistulas (63 +/- 8% versus 39 +/- 4%, p < 0.05). Fistula output and the initial response to octreotide treatment had no value in predicting spontaneous healing. In conclusion, octreotide is a valuable tool for the conservative treatment of fistulas of the digestive tract. It is especially valuable for management of high-output enteric fistulas and pancreatic fistulas.

Differential regional effects of octreotide on human gastrointestinal motor function

The effects of octreotide on regional motor function in the human gut are unclear. In a randomised, blinded study the effects of octreotide (50 micrograms, subcutaneously, three times daily) and placebo on gastric, small bowel, and colonic transit, and colonic motility and tone were assessed in 12 healthy volunteers whose colon had been cleansed. Octreotide accelerated initial gastric emptying (p = 0.05), inhibited small bowel transit (p < 0.01), and reduced ileocolonic bolus transfers (p < 0.05). Colonic transit was unaltered by octreotide; the postprandial colonic tonic response was inhibited (p < 0.05 v placebo), whereas colonic phasic pressure activity was increased by octreotide (p < 0.05 v placebo). These data support the use of octreotide in diarrhoeal states but not in diseases that cause small bowel stasis and bacterial overgrowth. Simultaneous measurements of colonic transit, tone, and phasic contractility are valid in studying the effects of pharmacological changes and may be applicable to the study of the human colon in health and disease.

The role of octreotide in palliative care

Octreotide, an analogue of somatostatin with a more favorable pharmacokinetic profile, is a new drug that may offer some advantages in the palliative care setting. It has been used with favorable results in the management of some gastrointestinal disorders, such as gastrointestinal hemorrhage, diarrhea, short-bowel syndrome, fistula, and intestinal occlusion in the palliative care setting. These favorable results occurred without important side effects, underlining the potential role of this drug. The cost-benefit ratio of this expensive drug must be considered, however.

Update on the management of intestinal cryptosporidiosis in AIDS

OBJECTIVE

To update readers on the pharmacotherapeutic management of cryptosporidiosis in patients with AIDS.

DATA SOURCES

A MEDLINE search was used to identify pertinent literature. Additionally, programs and abstracts from the 33rd Interscience Conference on Antimicrobial Agents and Chemotherapy; the 1st International Conference on Macrolides, Azalides, and Streptogramins; the 93rd American Society for Microbiology Meeting; and the 6th and 7th International Conferences on AIDS were used.

DATA EXTRACTION

Available data from in vitro, animal, and human experiments were reviewed.

DATA SYNTHESIS

Intestinal cryptosporidiosis in patients with AIDS can be a life-threatening opportunistic infection. However, there can be significant variability in disease expression, including spontaneous remission. Supportive care with hydration and nutritional supplementation remains a hallmark of therapy. Unfortunately, there is no proven specific pharmacotherapy of cryptosporidiosis in patients with AIDS. Numerous agents have been analyzed for in vitro activity and efficacy in experimental animal models and actual human cases of the infection, including paromomycin, azithromycin, clarithromycin, octreotide, hyperimmune bovine colostrum, bovine transfer factor, and many others. Because limited numbers of controlled trials have been conducted with potential therapeutic agents, the majority of the information to date is preliminary in nature.

CONCLUSIONS

Despite the availability of some evolving and potentially promising treatment modalities, further controlled clinical trials are necessary to evaluate the role of pharmacotherapy for intestinal cryptosporidiosis in patients with AIDS.

Bowel rest, intravenous hydration, and continuous high-dose infusion of octreotide acetate for the treatment of chemotherapy-induced diarrhea in patients with colorectal carcinoma

BACKGROUND

A prospective trial was conducted involving 16 patients with colorectal adenocarcinoma using a regimen of continuous-infusion octreotide acetate (Sandostatin [octreotide acetate], Sandoz, East Hanover, NJ for the treatment of severe diarrhea induced by the weekly schedule of 5-fluorouracil (5-FU) in combination with leucovorin who were refractory to opiate therapy.

METHODS

Fifteen patients had tissue-documented metastatic colorectal adenocarcinoma. An additional patient was treated adjuvantly. Fifteen patients were treated with chemotherapy consisting of 5-FU and high-dose leucovorin. The octreotide acetate regimen used was a continuous infusion of 50 micrograms/h for 12 hours followed by 100 micrograms/h for 12 hours and subsequently 150 micrograms/h for 72 hours. All patients were previous failures of diphenoxylate atropine (Lomotil diphenoxalate], Searle, Chicago, IL) given 2.5 mg orally after each loose bowel movement, but no more than 20 mg in a 24-hour period. Opiate therapy was not continued beyond 48 hours. All patients also were treated with bowel rest (nothing by mouth) and intravenous fluid hydration as well as octreotide acetate.

RESULTS

Complete resolution of diarrhea was seen in 15 of 16 patients (94%). In 4 patients this was accomplished during the 100 micrograms/h infusion, and in 11 patients during the 150 micrograms/h infusion. Recurrence of diarrhea was seen in two patients after a complete cycle of octreotide acetate. Both patients were restarted at 150 micrograms/h for 72 hours of octreotide acetate with resolution of the diarrhea within 36 hours of the infusion. No toxicity related to octreotide acetate was seen in this trial.

CONCLUSION

The continuous-infusion regimen of octreotide acetate 150 micrograms/h is an effective and safe schedule for the treatment of chemotherapy-induced diarrhea together with bowel rest and intravenous fluid hydration in a group of patients in whom the majority were treated with the weekly schedule of 5-FU and high-dose leucovorin.

Pharmacodynamic effects of Sandostatin in the gastrointestinal tract

Somatostatin (SST) is widely distributed throughout the human gastrointestinal system. There, it is found in neurons and fibers of both the submucosal and myenteric plexus and the pancreas, and also in the D cells of the stomach, gut, and pancreatic islets. Whereas in the intestinal nervous system, duodenum, and pancreas, somatostatin-14 (SST-14) appears to be the predominant molecular form, the endocrine-type D cells of the intestine primarily contain somatostatin-28 (SST-28). SST peptides may act very differently at different sites, as hormones, paracrine substances, or neurotransmitters. Because of this complexity of action, very little is known about the physiological effects of SST in the gastrointestinal tract. In contrast, the pharmacological actions of natural synthetic SST have been thoroughly studied and have given rise to many therapeutic applications. Octreotide, an analogue with a longer half-life and higher potency, has greatly facilitated the clinical application of SST. This review deals with the pharmacological effects of octreotide on different gastrointestinal functions. The SST analogue exerts a long-lasting inhibitory action on gastric acid, pancreatic enzyme, bicarbonate secretion, and on bile flow. It also inhibits stimulated intestinal secretion, ie, the release of neuropeptides from the gut and pancreas. It can also prolong orocecum transit time and prevent gallbladder contraction. It inhibits absorption of nutrients and exerts inhibitory effects on splanchnic hemodynamics. It is because of these actions that SST has attracted so much attention in the treatment of different gastrointestinal disorders.

Control of chemotherapy-induced diarrhoea with octreotide in patients receiving 5-fluorouracil

Chemotherapy treatment with combination of 5-fluorouracil and leucovorin or interferon alpha determined an incidence of severe diarrhoea of 10 and 20%, respectively. Up to date no treatment for this condition has been defined. 21 patients affected by advanced colorectal cancer and 6 patients affected by advanced pancreatic cancer received octreotide as treatment for severe diarrhoea following chemotherapy with 5-fluorouracil/leucovorin (Machover's regimen) or 5-fluorouracil/interferon (Wadler's regimen) combination. Octreotide was administered by subcutaneous injection of 50 micrograms twice daily on the first day and 100 micrograms twice daily on the second and third day. 26 patients had total cessation of diarrhoea: 4 patients within the first day, 6 within the second day and 16 within the third day. 1 patient had no change and after the last administration of octreotide he was treated with loperamide and intravenous hydration. Side effects have been mild. In summary octreotide seems to be an effective agent in the management of chemotherapy related diarrhoea.

Non-endocrine applications of somatostatin and octreotide acetate: facts and flights of fancy

Somatostatin, originally detected by Krulich and ultimately isolated by Brazeau, was initially described as a growth hormone release-inhibiting factor. Subsequent investigation into the use of native somatostatin and the development of long-acting somatostatin analogues, especially octreotide acetate, have fostered increasing uses of these compounds. Though the clinical and investigational uses of somatostatin and its analogues are varied, one central theme remains constant: the ability of these agents to suppress circulating peptide levels. This article, a review of the current non-endocrine applications of somatostatin and its analogues, covers a wide range of potential applications for somatostatin-like compounds. These include use in cirrhosis and variceal bleeding, peptic ulcer disease, pancreatic fistulas, acute and chronic pancreatitis, dumping syndrome, cancer therapy, small bowel fistulas, psoriasis, pain control, and autonomic hypotension. Somatostatin may also play a role in the development and potential treatment of neurologic disease and may have profound found influence on behavior.

Treatment of severe postvagotomy/postgastrectomy symptoms with the somatostatin analogue octreotide

Fourteen patients with severe and persistent postvagotomy/postgastrectomy symptoms were entered into a trial of treatment with the somatostatin analogue octreotide, 50 micrograms twice daily 30 min before meals being self-administered by subcutaneous injection. Six of the seven patients completing the 3-month trial showed sustained overall improvement of symptoms. The remaining patients were unhelped by treatment or developed unwanted effects. Six of eight patients with dumping syndrome showed sustained improvement of dumping symptoms during treatment. Bile vomiting was relieved in three of four patients with this complaint. Diarrhoea accompanying dumping showed a variable response to treatment, with improvement in three patients and no change or worsening of this symptom in five. Two patients with severe postvagotomy diarrhoea alone showed no improvement. Four patients with unwanted effects and three patients who found no benefit stopped the trial medication early. Four further patients reported mild or transient side-effects. For patients with severe postvagotomy/postgastrectomy symptoms, a trial of octreotide seems justified when significant dumping symptoms are present and other treatment options have been exhausted.

Successful closure of intestinal fistulae in an infant using the somatostatin analogue SMS 201-995

Enterocutaneous and other gastrointestinal fistulae create tough challenges with respect to wound care, nutrition, and strategy for closure. SMS 201-995 is a long-acting somatostatin analogue that has been effective in the treatment of adult enteric fistulae. The use of SMS 201-995 as an adjunct in the successful closure of intestinal fistulae in an infant is reported. This newborn infant developed a high-output enterocutaneous fistula and multiple enteroenteric fistulae after an intestinal resection for necrotizing enterocolitis. Copious fistulae output led to extensive wound breakdown, dehydration, and failure to thrive. Despite traditional management with bowel rest, total parenteral nutrition, antibiotics, and wound care, the high-output fistulae persisted unabated. On postoperative day 12, SMS 201-995 was started at 0.7 microgram/kg subcutaneously twice daily and gradually increased to 2.5 micrograms/kg. Within 2 days of SMS 201-995 therapy, the fistulae drainage had decreased from 62 mL/kg/d to 36 mL/kg/d, a 42% decrease from pretreatment levels. By day 8 of treatment, all fistulae had closed. After 14 days of treatment, the wound had healed and the infant was gaining weight. An upper gastrointestinal examination showed a patent ileostomy and no fistulae. Feeding was initiated, SMS 201-995 was discontinued without significant ileostomy output increase, and successful ileostomy closure took place 4 weeks posttreatment. Furthermore, the infant had no demonstrable side effects from the drug. Use of this drug should be considered in the treatment of other infants with complex, recalcitrant gastrointestinal fistulae.

Nutritional support of patients with AIDS

Investigators are now predicting that nearly 100% of the estimated 12 million HIV-positive persons in the world will develop AIDS. Most persons with AIDS will experience progressive weight loss and malnutrition prior to death. Because nutritional therapy clearly has a beneficial effect on the clinical course and immunologic status of the critically ill general population, one must not disregard its potential for benefits in the treatment of persons with AIDS. As a result of the escalating cost of medical therapy and the inevitable AIDS epidemic, the nutritional management of persons with AIDS must be simple to administer and cost effective. The author has developed nutritional screening criteria to identify those patients who would most benefit from nutritional therapy. Because these patients differ in their nutritional requirements, diet tolerance, and degree of gut dysfunction, there is no single nutritional therapy that can be used routinely to treat all malnourished persons with AIDS.

Diarrhoea--an unrecognised hazard of coeliac plexus block

Coeliac plexus block is a safe procedure with relatively few side-effects. We report two cases of persistent severe diarrhoea following coeliac plexus block and explore the possible reasons for this previously unrecognised side-effect. We postulate that somatostatin analogue may be useful as treatment for diarrhoea following neurolytic coeliac plexus block that is unresponsive to conventional anti-diarrhoeal agents.

Severe posthemicolectomy diarrhea: evaluation and treatment with SMS 201-995

The effect of subcutaneous somatostatin analogue SMS 201-995 (Sandoz Pharmaceuticals Corp., East Hanover, NJ) was investigated in a patient with acute postoperative secretory diarrhea. The patient was hospitalized with bowel obstruction caused by a descending colon adenocarcinoma. One week after left hemicolectomy and transverse colostomy, watery colostomy output, which exceeded 10 L per day developed. Jejunal perfusion studies suggested that the patient's diarrhea was caused by abnormal net secretion of water and electrolytes by the small intestine. Circulating levels of various peptide hormones were normal with the exception of elevated level of pancreatic polypeptide. SMS 201-995 administration reduced colostomy output and normalized many of the abnormalities found during jejunal perfusion. These results indicate that the patient's acute secretory diarrhea, occurring after large intestinal obstruction, originated in the small intestine and that SMS 201-995 can be used to manage this unusual severe postoperative problem.

Effect of a long acting somatostatin analogue SMS 201-995 on jejunostomy effluents in patients with severe short bowel syndrome

The effect of a long acting somatostatin analogue SMS 201-995 on stomal effluents in patients with severe short bowel syndrome was investigated in a double blind placebo controlled balance study. Six patients, five with Crohn's disease and one with radiation enteropathy were studied. Five patients had a jejunostomy and one an ileostomy. The patients had a normal food intake, but because of severe malabsorption had received home parenteral nutrition for several years. Faecal mass was reduced (p less than 0.005) and intestinal net sodium absorption was increased (p less than 0.005) by intravenous infusion of SMS 25 micrograms/h. Net absorption of potassium, calcium, magnesium phosphate, zinc, nitrogen and fat was not influenced. Subcutaneous injections of 50 micrograms SMS every 12 hours had a similar effect on net intestinal absorption of sodium and water. Four patients continued with a five to six months open follow up study when subcutaneous SMS in the same dose was administered by the patients at home. The effect on faecal sodium loss persisted, but in one patient faecal mass gradually increased and finally exceeded pretreatment values. SMS may decrease net absorption of water and sodium following reduced secretion of digestive juices rather than by increasing absorptive capacity. SMS may be useful as an antidiarrhoeal drug in patients with high output jejuno- or ileostomies, but in patients who need permanent parenteral nutrition the effect is too small to significantly alter management.

Clinical response to the long acting somatostatin analogue SMS 201-995 in a child with congenital microvillus atrophy

A 27 month old girl with congenital microvillus atrophy received two courses of SMS 201-995, a synthetic long acting analogue of native somatostatin, in an attempt to decrease profuse secretory diarrhoea. During the first trial at 13 months of age fluid and electrolytes administered by parenteral infusion were decreased as measured by water and faecal electrolyte losses. During the second trial of SMS 201-995 at 19 months fluid and electrolyte input were held constant for 14 days. Stool volume declined from 275 ml/kg to 161 ml/kg. Reductions in output of stool electrolytes (Na+, K+, Cl-) were accompanied by an increase in urine fluid output and increased excretion of urinary Na+. Subsequent administration of SMS 201-995 for a nine month period was not associated with adverse side effects or an impairment of growth velocity. These findings suggest that SMS 201-995 may be useful therapy in infants with high output diarrhoea as a result of congenital microvillus atrophy.

Effect of somatostatin analog (SMS 201-995) on in vivo intestinal fluid transport in rats. A limited systemic effect

Somatostatin analog, SMS 201-995, effectively inhibits the release of hormones from gastrointestinal endocrine tumors and reduces hormonally mediated diarrheas. Its clinical efficacy in nonhormonally mediated diarrhea is limited, despite a potent antisecretory and proabsorptive effect in vitro. The effect of serosal addition of SMS 201-995 on in vitro short-circuit current responses in rat intestine is dependent upon chloride and more marked in colon and ileum than jejunum. In contrast, in vivo loop studies demonstrated that systemic administration of SMS 201-995 for five consecutive days produced a paradoxical decrease in basal colonic fluid absorption with no effect in jejunum or ileum. Furthermore, systemically administered SMS 201-995 did not alter cholera toxin-stimulated intestinal secretion. We conclude that despite a previously identified intestinal antisecretory and proabsorptive effect of SMS 201-995 in vitro, this effect is not seen in vivo and may explain the limited use of SMS 201-995 as an antidiarrhoeal agent in nonhormonally mediated diarrhoea.