Malabsorption of fat and vitamin B12 before and after intestinal resection for Crohn's disease

From Gut to Brain: Uncovering Potential Serum Biomarkers Connecting Inflammatory Bowel Diseases to Neurodegenerative Diseases

Inflammatory bowel diseases (IBDs) are characterized by chronic gastrointestinal inflammation due to abnormal immune responses to gut microflora. The gut-brain axis is disrupted in IBDs, leading to neurobiological imbalances and affective symptoms. Systemic inflammation in IBDs affects the brain's inflammatory response system, hormonal axis, and blood-brain barrier integrity, influencing the gut microbiota. This review aims to explore the association between dysregulations in the gut-brain axis, serum biomarkers, and the development of cognitive disorders. Studies suggest a potential association between IBDs and the development of neurodegeneration. The mechanisms include systemic inflammation, nutritional deficiency, GBA dysfunction, and the effect of genetics and comorbidities. The objective is to identify potential correlations and propose future research directions to understand the impact of altered microbiomes and intestinal barrier functions on neurodegeneration. Serum levels of vitamins, inflammatory and neuronal damage biomarkers, and neuronal growth factors have been investigated for their potential to predict the development of neurodegenerative diseases, but current results are inconclusive and require more studies.

Exocrine pancreatic insufficiency and fat malabsorption related to pancreatectomy and other gastrointestinal surgery: A narrative review

Surgical resection is the mainstay of treatment for patients with tumors of the pancreas. There are a number of well-recognized complications that account for the significant morbidity associated with the operation, including exocrine pancreatic insufficiency (EPI). Patients with pancreatic cancer commonly have evidence of EPI prior to surgery, and this is exacerbated by an operation, the extent of the insult being dependent on the indication for surgery and the operation performed. There are accumulating data to demonstrate that treatment of EPI with pancreatic enzyme replacement (PERT) enhances clinical outcomes after surgery by reducing critical complications; this in turn may enhance oncological outcomes. Data would indicate that quality of life (QoL) is also improved after surgery when enzymes are prescribed. To date, many surgeons and clinicians have not appreciated the need for PERT or the benefits it may bring to their patients; therefore, education of clinicians remains a significant opportunity. In turn, patient education about consumption of the correct dose of enzymes at the appropriate time is key to an optimal outcome. In addition, because of the complex nature of the regulation of pancreatic exocrine function, there is evidence to support the presence of EPI following operations performed on other gastrointestinal (GI) organs, including the esophagus, stomach, and small intestine. The aim of this review is to document the existing published evidence in relation to EPI and its treatment with PERT following GI surgery.

Advances in the Comprehensive Management of Postoperative Crohn's Disease

Patients with postoperative Crohn's disease are difficult to manage because of their risk of experiencing a more severe course, multiple symptom confounders, and poor sensitivity of symptomatic remission to rule out intestinal inflammation. In this group, data are lacking on biologic therapeutic efficacy, and recommendations are lacking for those with multiple medication failures. Novel noninvasive testing can simultaneously exclude alternate causes of symptoms (serum C4, fecal fat, small intestinal bowel overgrowth breath testing) and assess intestinal inflammation (fecal calprotectin, endoscopic healing index). In addition, endoscopy-based disease activity assessment and management are required. Endoscopy should be performed within 6 months of surgery, and aggressive disease activity monitoring can be considered with colonoscopy every 1-2 years subsequently to ensure late recurrence is detected. Patients with multiple resections should be screened for short bowel syndrome. Predictive biomarkers are needed to guide medication selection in this high-risk population. Postoperative prophylactic biologic therapy is prudent for patients with preoperative biologic failure. However, there are no high-quality data to guide which agent should be selected. Selecting biologics with an alternative mechanism of action in those who had failed a biologic with adequate drug concentrations and selection of different agents in those with previous intolerance are reasonable. Significantly more study is required to assess the efficacy of therapies in this setting.

Quality of life and colorectal function in Crohn's disease patients that underwent ileocecal resection during childhood

Psychosocial and functional outcomes after intestinal resection in pediatric Crohn's disease (CD) are lacking. Therefore, we (I) assessed health-related quality of life (HRQOL), colorectal function, and satisfaction with surgery and (II) investigated their relationship with surgical outcomes, after ileocecal resection for CD. Crohn's patients that underwent ileocecal resection during childhood were included. HRQOL and colorectal function were assessed using SF-36 and COREFO, respectively, and compared with reference values. Satisfaction was scored on a 5-point Likert scale. In total, 80 patients (50% male, median age 23.0 years) were included. Physical HRQOL was impaired (SF-36 [mean]: CD, 47 vs. general, 54; p < 0.001), while mental HRQOL was similar to that in the general population. Overall colorectal function was impaired (COREFO [mean]: CD, 12.6 vs. normal, 7.2; p < 0.001). Worse colorectal function was associated with increasing clinical disease activity and longer interval since resection. Majority of patients was satisfied with surgery (81% satisfied/very satisfied, 11% neither satisfied nor dissatisfied, 8% dissatisfied/very dissatisfied). Decreased satisfaction with surgery was associated with increased clinical disease activity but not related to colorectal function.Conclusions: Physical HRQOL and colorectal function in CD patients who underwent ileocecal resection during childhood seem impaired and related to adverse surgical outcomes. This emphasizes the need for post-operative monitoring and prophylactic therapies. What is Known: • Up to 25% of pediatric-onset Crohn's disease (CD) patients undergo an intestinal resection within 5 years from diagnosis. • Many children and adults with CD experience disruption of their daily activities and health-related quality of life (HRQOL). What is New: • Physical HRQOL and colorectal function are impaired in patient with CD that underwent ileocecal resection during childhood. • Increasing clinical disease activity, a longer interval since surgery, severe complications related to surgery, and recurrent surgeries are all associated with worse colorectal function.

Less common etiologies of exocrine pancreatic insufficiency

Exocrine pancreatic insufficiency (EPI), an important cause of maldigestion and malabsorption, results from primary pancreatic diseases or secondarily impaired exocrine pancreatic function. Besides cystic fibrosis and chronic pancreatitis, the most common etiologies of EPI, other causes of EPI include unresectable pancreatic cancer, metabolic diseases (diabetes); impaired hormonal stimulation of exocrine pancreatic secretion by cholecystokinin (CCK); celiac or inflammatory bowel disease (IBD) due to loss of intestinal brush border proteins; and gastrointestinal surgery (asynchrony between motor and secretory functions, impaired enteropancreatic feedback, and inadequate mixing of pancreatic secretions with food). This paper reviews such conditions that have less straightforward associations with EPI and examines the role of pancreatic enzyme replacement therapy (PERT). Relevant literature was identified by database searches. Most patients with inoperable pancreatic cancer develop EPI (66%-92%). EPI occurs in patients with type 1 (26%-57%) or type 2 diabetes (20%-36%) and is typically mild to moderate; by definition, all patients with type 3c (pancreatogenic) diabetes have EPI. EPI occurs in untreated celiac disease (4%-80%), but typically resolves on a gluten-free diet. EPI manifests in patients with IBD (14%-74%) and up to 100% of gastrointestinal surgery patients (47%-100%; dependent on surgical site). With the paucity of published studies on PERT use for these conditions, recommendations for or against PERT use remain ambiguous. The authors conclude that there is an urgent need to conduct robust clinical studies to understand the validity and nature of associations between EPI and medical conditions beyond those with proven mechanisms, and examine the potential role for PERT.

Nutrition Issues in Pediatric Crohn's Disease

Twenty-five percent of inflammatory bowel disease (IBD) diagnoses present in childhood, with Crohn's disease (CD) being the most common type. Many children have poor nutrition status at presentation of the disease, which may worsen during the clinical course, with a significant number of children having impaired linear growth. The cause of this poor nutrition status is complex, and contributing factors include inadequate intake, malabsorption, altered energy demands, and losses through stool, particularly in colitis. The principal aim of medical management is to induce disease remission, with minimal side effects, thereby enabling normal growth and development. This must include active consideration of the nutrition needs of such children and how they may be best met. However, our understanding of the manner in which the disease process affects the energy demands of children with CD or how poor nutrition, in turn, may affect the disease course is limited. This may constrain the efficacy and effectiveness of standard therapeutic approaches to care. This review explores the many factors of relevance in the delivery of nutrition support to children with inflammatory bowel disease, and explores the role of exclusive enteral nutrition as a corticosteroid-sparing strategy to induce remission in children with active Crohn's disease.

Vitamin B12 deficiency in inflammatory bowel disease: prevalence, risk factors, evaluation, and management

BACKGROUND

Management of vitamin B(12) (cobalamin, Cbl) deficiency in inflammatory bowel disease (IBD) is often not evidenced-based because of uncertainty on whether it causes enough malabsorption to result in clinical disease. This systematic review examines whether IBD predisposes to Cbl deficiency. We provide an approach to the management of abnormal Cbl values in IBD based on current literature and consensus-based guidelines.

METHODS

An extensive search of the Ovid MEDLINE and EMBASE databases by independent reviewers identified 42 articles with a total of 3732 patients evaluating Cbl deficiency in IBD.

RESULTS

Crohn's disease without ileal resection, regardless of disease location in the ileum, did not increase the risk for Cbl deficiency. Ileal resections greater than 30 cm were associated with Cbl deficiency in Crohn's disease, whereas those less than 20 cm were not. The effects of 20 to 30 cm resections were inconsistent. Ulcerative colitis did not predispose to deficiency. All studies failed to use confirmatory biomarker testing as stipulated by diagnostic guidelines for Cbl deficiency.

CONCLUSIONS

This literature does not support an association of Crohn's disease in general, regardless of ileal involvement, with Cbl deficiency. Only ileal resections greater than 20 cm in Crohn's disease predispose to deficiency and warrant treatment. Based on these findings, we suggest a diagnostic and therapeutic algorithm. All findings and recommendations require verification in further studies using confirmatory biomarkers as per diagnostic guidelines for Cbl deficiency. Serum Cbl levels alone are likely insufficient to diagnose deficiency in asymptomatic patients.

Metabolic consequences after urinary diversion

Metabolic disturbances are well-known, but sometimes neglected immediate consequences or late sequelae following urinary diversion (UD) using bowel segments. Whereas subclinical disturbances appear to be quite common, clinically relevant metabolic complications, however, are rare. Exclusion of bowel segments for UD results in loss of absorptive surface for its physiological function. Previous studies demonstrated that at least some of the absorptive and secreting properties of the bowel are preserved when exposed to urine. For each bowel segment typical consequences and complications have been reported. The use of ileal and/or colonic segments may result in hyperchloremic metabolic acidosis, which can be prevented if prophylactic treatment with alkali supplementation is started early. The resection of ileal segments may be responsible for malabsorption of vitamin B12 and bile acids with subsequent neurological and hematological late sequelae as well as potential worsening of the patient's bowel habits. Hence, careful patient and procedure selection, meticulous long-term follow-up, and prophylactic treatment of subclinical acidosis is of paramount importance in the prevention of true metabolic complications.

Urinary diversion--approaches and consequences

BACKGROUND

Bladder cancer is not a rare disease: In 2010, there were more than 70 000 affected patients in the United States. Radical cystectomy for the treatment of muscle invasive bladder cancer necessitates urinary diversion.

METHODS

We present the current options for urinary diversion and their different indications on the basis of a selective search for pertinent literature in PubMed and our own clinical experience.

RESULTS

When bladder cancer is treated with curative intent, continence-preserving orthotopic urinary bladder replacement is preferred. For heterotopic urinary bladder replacement, a reservoir is fashioned from an ileal or ileocecal segment. Urine is diverted to the rectum by way of the sigmoid colon. When bladder cancer is treated with palliative intent, non-continence-preserving cutaneous urinary diversion is usually performed: The creation either of a renal-cutaneous fistula or a self-retaining ureteral stent is a purely palliative procedure. In these interventions, the resorptive surface of the bowel segment used can no longer play its original physiological role in the gastrointestinal tract, even though its absorptive and secretory functions are still intact. This has metabolic consequences, because the diverted urine here comes into contact with a large area of bowel epithelium. Early preventive treatment must be provided against potentially serious complications such as metabolic acidosis and loss of bone density. The resection of ileal segments can also lead to malabsorption. The risk of secondary malignancy is elevated after either continence-preserving anal urinary diversion (>2%) or bladder augmentation (>1%).

CONCLUSION

There are four options for urinary diversion after cystectomy that can be performed when surgery is performed with either curative or palliative intent. There are also a number of purely palliative interventions.

[Metabolic long-term complications after urinary diversion]

Metabolic long-term complications and consequences after urinary diversion are somewhat neglected. Subclinical metabolic disturbances are quite common; however, complications are rare. The absorptive surface of the bowel segment is lost for the physiological function of the gastrointestinal tract. Some studies demonstrated that at least some of the absorbent and secreting properties of the bowel are preserved if exposed to urine. For each bowel segment typical complications are reported. Using ileal and/or colon segments, hyperchloremic metabolic acidosis may occur. Studies demonstrated that metabolic effects are not as severe as suspected and could be prevented if a prophylactic treatment is started early.The resection of ileal segments is responsible for malabsorption of vitamin B(12) and bile acid; when using colonic segments, electrolyte disturbances are more common. Careful patient selection, meticulous follow-up and prophylactic treatment are crucial to prevent metabolic complications.

Bladder augmentation and urinary diversion in patients with neurogenic bladder: non-surgical considerations

Segments from almost all parts of the bowel have been used for urinary diversion. As a result, the available absorptive surface area of the bowel is reduced, and the incorporation of bowel segments into the urinary tract may have metabolic consequences. This is an area somewhat neglected in the literature. Metabolic complications are rare, but sub-clinical metabolic disturbances are quite common. Several studies have demonstrated that some of the absorbent and secreting properties of the bowel tissue are preserved after incorporation into the urinary tract. Hyperchloraemic metabolic acidosis can occur if ileal and/or colon segments are used, as well as malabsorption of vitamin B(12) and bile acid after the use of ileal segments. These metabolic effects are not as severe as may be suspected and can be prevented by prophylactic substitution. Secondary malignancies can develop as a long-term consequence of bladder augmentation. Using colonic segments, tumours are most likely to occur at the ureteral implantation site. To prevent metabolic complications, careful patient selection and meticulous and lifelong follow up, as well as prophylactic treatment, are mandatory. Endoscopy for early detection has been recommended, starting 10 years postoperatively for patients who underwent surgery for a benign condition.

Metabolic phenotyping of the Crohn's disease-like IBD etiopathology in the TNF(ΔARE/WT) mouse model

The underlying biochemical consequences of inflammatory bowel disease (IBD) on the systemic and gastrointestinal metabolism have not yet been fully elucidated but could help to better understand the disease pathogenesis and to identify tissue-specific markers associated with the different disease stages. Here, we applied a metabonomic approach to monitor metabolic events associated with the gradual development of Crohn's disease (CD)-like ileitis in the TNF(ΔARE/WT) mouse model. Metabolic profiles of different intestinal compartments from the age of 4 up to 24 weeks were generated by combining proton nuclear magnetic resonance ((1)H NMR) spectroscopy and liquid chromatography-mass spectrometry (LC-MS). From 8 weeks onward, mice developed CD similar to the immune and tissue-related phenotype of human CD with ileal involvement, including ileal histological abnormalities, reduced fat mass and body weight, as well as hallmarks of malabsorption with higher energy wasting. The metabonomic approach highlighted shifts in the intestinal lipid metabolism concomitant to the histological onset of inflammation. Moreover, the advanced disease status was characterized by a significantly altered metabolism of cholesterol, triglycerides, phospholipids, plasmalogens, and sphingomyelins in the inflamed tissue (ileum) and the adjacent intestinal parts (proximal colon). These results describe different biological processes associated with the disease onset, including modifications of the general cell membrane composition, alteration of energy homeostasis, and finally the generation of inflammatory lipid mediators. Taken together, this provides novel insights into IBD-related alterations of specific lipid-dependant processes during inflammatory states.

The aetiology and impact of malnutrition in paediatric inflammatory bowel disease

Disease-associated undernutrition of all types is very common in paediatric inflammatory bowel disease (IBD). Recent weight loss remains one of the triad of clinical manifestations and a cornerstone for the diagnosis of Crohn's disease (CD), although significantly fewer patients now present as being underweight. Recent evidence suggests that the introduction of medical treatment will quickly restore body weight, although this does not reflect concomitant changes in body composition. CD children present with features of nutritional cachexia with normal fat stores but depleted lean mass. Poor bone health, delayed puberty and growth failure are additional features that further complicate clinical management. Suboptimal nutritional intake is a main determinant of undernutrition, although activation of the immune system and secretion of pro-inflammatory cytokines exert additional independent effects. Biochemically low concentrations of plasma micronutrients are commonly reported in IBD patients, although their interpretation is difficult in the presence of an acute phase response and other indices of body stores adequacy are needed. Anaemia is a common extraintestinal manifestation of the IBD child. Iron-deficient anaemia is the predominant type, with anaemia of chronic disease second. Decreased dietary intake, as a result of decreased appetite and food aversion, is the major cause of undernutrition in paediatric IBD. Altered energy and nutrient requirements, malabsorption and increased gastrointestinal losses are additional factors, although their contribution to undernutrition in paediatric CD needs to be studied further.

Mechanisms of growth impairment in pediatric Crohn's disease

Crohn's disease manifests during childhood or adolescence in up to 25% of patients. The potential for linear growth impairment as a complication of chronic intestinal inflammation is unique to pediatric patient populations. Insulin-like growth factor I (IGF-I), produced by the liver in response to growth hormone (GH) stimulation, is the key mediator of GH effects at the growth plate of bones. An association between impaired growth in children with Crohn's disease and low IGF-I levels is well recognized. Early studies emphasized the role of malnutrition in suppression of IGF-I production. However, a simple nutritional hypothesis fails to explain all the observations related to growth in children with Crohn's disease. The direct, growth-inhibitory effects of proinflammatory cytokines are increasingly recognized and explored. The potential role of noncytokine factors, such as lipopolysaccharides, and their potential to negatively influence the growth axis have recently been investigated with intriguing results. There is now reason for optimism that the modern anticytokine therapeutic agents available for treating children and adolescents with Crohn's disease will reduce the prevalence of this otherwise common complication. As our understanding of the mechanisms that underlie growth impairment advance, so too should the opportunity for developing further novel and targeted therapies.

Malabsorption is a major contributor to underweight in Crohn's disease patients in remission

OBJECTIVE

Undernutrition has been reported in 65-75% of patients with Crohn's disease. The present study aimed at identifying the relative contribution of malnutrition-causing factors in patients with Crohn's disease in remission.

METHODS

Sixteen patients with Crohn's disease (age 19-57 y) in remission (Crohn's Activity Disease Index < 150) were included in the study. Their weight was stable for >3 mo and they were off steroids. They all completed 3-d food records and concomitantly collected stools. Self-reported food records were analyzed and energy content in stools was determined by a direct bomb calorimeter. Resting energy expenditure (REE) was studied by indirect calorimetry and body composition by dual-energy X-ray absorptiometry. The study cohort was divided into two groups, with a body mass index (BMI) equal to 18.5 kg/m(2) serving as a cutoff point.

RESULTS

Subjects with lower BMIs tended to have less lean body mass (P = 0.006), less bone mineral density (P = 0.006), and lower REE (P = 0.003). No correlation was found between BMI and energy intake but the percentage of malabsorption was negatively correlated with BMI (P = 0.07). When dividing the study based on a BMI of 18.5 kg/m(2), no difference was found in caloric intake or REE between groups but subjects with lower BMIs had significant prominent malabsorption compared with the others (21.1 +/- 9.8% versus 11.7 +/- 3.5%, P = 0.015).

CONCLUSION

In the presence of similar energy intake, REE does not seem to contribute to lower BMI, although nutrient malabsorption is higher in malnourished patients with Crohn's disease in remission. We suggest that malabsorption be evaluated in patients with Crohn's disease who fail to gain weight during disease remission to establish their extra caloric requirements.

Urinary diversion: options, patient selection, and outcomes

Improved survival following radical cystectomy for bladder cancer as a result of advancements in combination chemotherapy and surgical technique has resulted in a philosophical change in the surgeon's approach to urinary diversion selection. Aims have evolved from the mere diversion of urine to a functional bowel conduit such as an ileal conduit or ureterosigmoidostomy, to providing the optimal diversion for the patient's quality of life. While quality of life is important, one must also consider the stage of cancer and individual patient comorbidities. Which diversion provides the best local cancer control, the lowest potential for complications (short and long term), and the easiest emotional adjustment in lifestyle while still allowing the timely completion of chemotherapy and therapeutic goals? A multidisciplinary approach to diversion selection that includes the patient, the medical oncologist, radiation oncologist, internist, and surgeon is ideal. We describe the three most commonly used types of diversions today, including conduits, continent cutaneous reservoirs, and orthotopic urethral diversions, as well as issues relative to patient selection and functional outcomes in patients undergoing radical cystectomy for the treatment of bladder cancer.

Systematic review: managing anaemia in Crohn's disease

BACKGROUND

Anaemia is a serious complication of Crohn's disease that triggers hospitalization and, if not interfered with, may lead to death.

AIMS

To systematically summarize and compare the literature on anaemia in Crohn's disease.

METHODS

For this systematic review the literature was searched for English-language articles using anaemia, Crohn* and IBD as key words. 144 articles were identified and sorted according to the following topics: prevalence, aetiology, diagnostic tests and therapy.

RESULTS

The reported prevalence of anaemia varied between 6.2% and 73.7%, with higher reported frequencies in older studies and in in-patients. Iron deficiency is the most common underlying condition. Vitamin B12 deficiency is related to the extent of ileal resection but has rarely impact on anaemia. Diagnostic criteria are not established and treatment guidelines are missing. Oral iron supplementation seems effective for short periods but intolerance leads to discontinuation in up to 21%. Eleven of 11 studies show that oral iron enhances intestinal inflammation and colon carcinogenesis in animal models of colitis. Intravenous iron supplementation with iron sucrose has been tested in over 250 Crohn's disease patients, is safe, effective and does not carry such hazards.

CONCLUSIONS

As disease activity is determining the degree of anaemia in Crohn's disease, implementation of more effective therapy for Crohn's disease will lower its incidence. However, further studies regarding the safety and effectiveness of iron supplementation are needed.

Follow-up strategies and management of recurrence in urologic oncology bladder cancer:

A surveillance program following cystectomy should consider a patient's individual risk for the development of local and distant recurrences and any specific needs related to the urinary tract reconstruction performed (Table 1). Well-documented recurrence patterns following cystectomy are available from many large surgical series and provide the background information needed for tailoring follow-up based on pathologic criteria. Economic issues also must be considered, given that the health care-related expenses of treating and following patients with bladder cancer is twice as much as that expended for the treatment of prostate cancer. Because of the ever-increasing fiscal constraints placed on clinicians, risk-adjusted follow-up strategies are reasonable, but will require prospective evaluation to validate their appropriateness.

Vitamin B12 and folate after 5-12 years of continent ileal urostomy (Kock reservoir) in children and adolescents

OBJECTIVE

To assess B12 and folate deficiency after continent urinary diversion via a Kock continent urinary reservoir in children and adolescents.

METHODS

Ten boys and 10 girls (10.8-18 years old at surgery) were operated with a Kock reservoir and followed for 5-12 years (mean 8.5). The follow-up period was divided into early (3 months-5 years, EFU) and late (5-12 years, LFU) follow-up. Patients were investigated for haemoglobin, serum iron, total iron binding capacity (TIBC), serum Vitamin B12, serum and blood folate, methylmalonic acid (MMA), homocystine and glomerular filtration rate.

RESULTS

Two patients developed subnormal B12 values (median 107.5 pmol/l), one at the EFU, and the other at LFW. The B12 value decreased during the LFU compared to the EFU in nine patients, but it was still within the normal range. Two patients with renal impairment had elevated MMA with normal B12 values. Five patients had high values of homocystine with folate deficiency and/or B12 deficiency and renal impairment. Plasma folate mean value was normal during the whole follow-up. Blood folate was below normal in five patients at the EFU. Two of these five patients, in addition to three patients, had low values at the LFU. Three of four patients with remaining short terminal ileum (20-45 cm) had normal B12 values at both the EFU & LFU and one had low values at the LFU. Six patients had subnormal GFR at the LFU.

CONCLUSIONS

To a similar degree as in adults, Vitamin B12, folate and iron deficiency can occur in children and adolescents after continent urinary diversion using an ileal segment. Therefore, Vitamin B12 and folate should be monitored regularly in these patients. Serum MMA and homocystine may offer increased detection of Vitamin B12 deficiency, especially in the patients with normal renal function. Vitamin B12 deficiency is neither correlated with the time elapsed since surgery, nor with the ileum length. Patients are usually asymptomatic, so patients with true B12 deficiency should be identified and placed on life-long Vitamin B12 therapy. An adequate synthetic folic acid as supplements or fortified food is recommended for patients with folate deficiency.

Long-term assessment of serum vitamin B(12) concentrations in patients with various types of orthotopic intestinal neobladder

OBJECTIVES

Vitamin B(12) deficiency is an important long-term problem after urinary diversion using an intestinal segment. In this study, we examined serum vitamin B(12) concentrations in patients with neobladders constructed from various intestinal segments to determine the anatomic factors important for avoiding vitamin B(12) deficiency.

METHODS

Twenty-two patients (19 men and 3 women) had an ileal neobladder (modified Studer type); 9 men had an ascending colonic neobladder (Goldwasser type); 30 patients (24 men and 6 women) had a sigmoid neobladder (modified Reddy type); and 18 (15 men and 3 women) had an ileocolic neobladder (Mainz type). The postoperative follow-up ranged from 3 months to 11 years (mean +/- SD, 3.4 +/- 2.8 years). The serum vitamin B(12) concentration was determined at several points after surgery.

RESULTS

No patient with a neobladder fashioned from ascending or sigmoid colon developed a low vitamin B(12) concentration. Of the 18 patients with an ileocolic neobladder, 3 (16.6%) developed decreased serum vitamin B(12) concentrations after 5 to 6 years. Of the 22 patients with an ileal neobladder, 3 (13.6%) developed a low serum concentration of vitamin B(12) between 9 months and 3 years after surgery. No patient developed megaloblastic anemia or neurologic symptoms.

CONCLUSIONS

Preservation of the terminal 15 cm of ileum is not sufficient to ensure adequate vitamin B(12) absorption, and thus, preserving the ileal length is important. Use of colonic segments to construct neobladders appears to be preferable to ileal segments to preserve vitamin B(12) absorption.

Crohn's disease in adolescents

The clinical features of Crohn's disease manifest during adolescence are varied as in adults. The potential complication of growth impairment and concomitant delay in pubertal development is unique to this population. Cytokines released from the inflamed bowel and chronic nutritional insufficiency are the major factors in the pathophysiology of growth inhibition. Hence reduction of intestinal inflammation and consistent provision of adequate nutrition are of paramount importance in management. Drug treatment mirrors that of adults; few specifically paediatric clinical trials have been conducted. Enteral nutrition is an important therapeutic alternative for young patients. There is evidence that it constitutes both a primary therapy of inflammation and a means of providing the calories needed for growth. In the setting of extensive disease, dependency on corticosteroids should be minimized through judicious administration of immunosuppressive drugs. For an adolescent with localized stenotic disease, optimal management includes a timely referral for intestinal resection as a means of providing an asymptomatic interval during which growth and pubertal development can normalize.

Crohn's disease: nutrition and nutritional therapy

Disordered nutrition is common in Crohn's disease and is multifactorial. Regular and systematic monitoring of at least a minimum set of nutrition data is an essential component of care of children and adults with Crohn's disease. However, even in children, monitoring of growth and development may be deficient. Multiple macro- and micronutrient deficiencies are common in Crohn's disease, especially in those with extensive small bowel deficiencies or after multiple surgical resections. Body composition analysis may show differences from simple starvation, and metabolic effects of inflammation are increasingly being recognized. Nutritional support is part of the management of all patients with Crohn's disease, but nutritional intervention with defined formula liquid diet is an effective specific anti-inflammatory therapy. Although meta-analysis of published trials suggest that steroids are more effective than defined formula liquid diets, objective evidence from whole gut lavage fluid analysis and from faecal excretion of radiolabelled leukocytes shows unequivocal benefit of elemental diet based on measuring parameters of tissue damage. Enteral feeding with liquid diets should be considered in patients with incomplete small bowel obstruction, severe painful perianal disease, failure of corticosteroids in active Crohn's disease, borderline intestinal failure and in children with active Crohn's disease or with growth failure.

Quality of life after pouch excision

BACKGROUND

Pouch excision is a devastating experience for patients having restorative proctocolectomy for ulcerative colitis.

METHODS

The quality of life among patients having pouch excision for ulcerative colitis was compared with that in those having proctocolectomy and ileostomy for ulcerative colitis using a validated standardized self-administered questionnaire.

RESULTS

After pouch excision patients (n = 9) had more troublesome bowel symptoms (mainly from liquid stoma output) than those in the proctocolectomy group (n = 14) (mean(s.d.) score 5.64(0.92) versus 6.13(0.37), P = 0.03). However, the mean scores for the other parameters (systemic symptoms, functional, social and emotional impairment) did not differ significantly.

CONCLUSION

Patients having pouch excision for ulcerative colitis have more liquid ileostomy loss but a comparable quality of life to those treated by standard proctocolectomy and ileostomy.

No evidence of osteopenia 5 to 8 years after ileal orthotopic bladder substitution

PURPOSE

The use of bowel segments as bladder substitutes may result in chronic, impaired vitamin D and calcium metabolism, and ultimately in bone demineralization.

MATERIALS AND METHODS

Bone metabolism was examined in 14 patients who lived for 5 to 8 years with an ileal low pressure bladder substitute after radical cystectomy for bladder cancer. Bone mineral density was measured using dual energy x-ray absorptiometry of the total skeleton, lumbar spine, femoral neck, and tibial epiphysis and diaphysis. Laboratory studies included serum levels of 1,25-dihydroxyvitamin D, 25-hydroxyvitamin D, intact parathyroid hormone, plasma alkaline phosphatase, electrolytes, creatinine and blood gas analysis.

RESULTS

Bone mineral density was normal in all patients. There was no evidence of deficient vitamin D stores. There was a tendency toward slightly elevated serum creatinine values in patients with preexisting impaired renal function, including 1 who also had slight acidosis. No patient had hyperchloremia.

CONCLUSIONS

We found no evidence of osteomalacia, osteoporosis or significant metabolic acidosis in 14 patients with an ileal bladder substitute for 5 to 8 years. However, it is not known whether the absence of osteopenia would also apply to patients with poor renal function, to those not followed meticulously and, thus, at risk for major long-term functional or metabolic disturbances from the ileal bladder substitute or to patients with orthotopic bladder substitutes made from longer or other bowel segments than we used.

Direct and quantitative vitamin B12 absorption measurement in patients with disorders in the distal part of the bowel. Comparison of stool spot test [SST] with whole body counting in patients with ileal pelvic reservoir, ileostomy or Crohn's disease

Direct and quantitative vitamin B12 absorption studies were performed in 25 patients with disorders in the distal small intestine using whole body counting as the gold standard. Simultaneously, vitamin B12 absorption was also determined by the more simple stool spot test (SST) which incorporates 51CrCl3 as a nonabsorbable marker. The SST provided a reliable direct and quantitative measure of vitamin B12 absorption in patients with previous ileal resections due to Crohn's disease (CD) (n = 7) as compared with whole body counting. In ulcerative colitis (UC) patients with either an ileal pelvic reservoir (n = 10) or a conventional ileostomy (n = 8), markedly shorter bowel transit times and absence of colon may have hindered sufficient mixture of the tracer and marker isotopes which could explain the false absorption values according to the SST in single patients. Therefore, an intact colon and a near-normal bowel transit time seem to be essential for performance of the SST. Whole body counting showed, as expected, that all CD patients except one had decreased vitamin B12 absorption (median 23%; range 3-39%) (normally > 35%). In UC patients with ileostomy, only one had a markedly decreased vitamin B12 absorption, two borderline normal values, while the rest had normal values (median 54%, range 15-76%). All UC patients with ileal pelvic reservoir had normal vitamin B12 absorption values (median 40.5%, range 36-87%). We conclude that vitamin B12 substitution therapy is probably required in patients with CD with ileal resection.(ABSTRACT TRUNCATED AT 250 WORDS)

A triple isotope technique for estimation of fat and vitamin B12 malabsorption in Crohn's disease

A test for simultaneous estimation of vitamin B12 and fat absorption from stool samples was investigated in 25 patients with severe diarrhoea after operation for Crohn's disease. 51CrCl3 was ingested as a non-absorbable marker, 58Co-cyano-cobalamin as vitamin B12 tracer, and 14C-triolein as lipid tracer. Faeces were collected separately for 3 days. Some stool-to-stool variation in the 58Co/51Cr and 14C/51Cr ratios was seen. When the 58Co-B12 and 14C-triolein excretion was estimated in samples of the two stools with the highest activities of 51Cr, the variations of the estimates were less than +/- 10% and +/- 15% of the doses ingested, respectively. Twelve of the 25 patients were not able to collect faeces and urine quantitatively and separately. However, in all patients faeces with sufficient radioactivity for simultaneous estimation of faecal 58Co-B12 and 14C-triolein excretion from stool samples were obtained.

Intrinsic factor secretion and cobalamin absorption. Physiology and pathophysiology in the gastrointestinal tract

Intrinsic factor is produced by the gastric parietal cell. Its secretion is stimulated via all pathways known to stimulate gastric acid secretion: histamine, gastrin, and acetylcholine. There is, however, a different mode of secretion for both substances: atropine, vagotomy, and H2 receptor antagonists inhibit both intrinsic factor and acid secretion, but secretin and the hydrogen-potassium ATPase antagonist omeprazole have no effect on intrinsic factor while substantially reducing acid secretion. Cobalamin in food is bound to animal protein. Cobalamin deficiency due to inadequate dietary intake is rarely seen in extreme vegetarians (vegans). In the stomach cobalamin is liberated from its protein binding by peptic digestion and bound to R-proteins. Hypochlorhydria or achlorhydria, whether medically induced or not, may impair cobalamin uptake. The cobalamin-R-protein complex is split by pancreatic enzymes in the duodenum, where cobalamin is bound to intrinsic factor. Pancreatic insufficiency may lead to cobalamin deficiency. Lack of intrinsic factor is the commonest cause of cobalamin deficiency; very rarely, aberrant forms of intrinsic factor are produced, but the clinical syndrome is similar. Gram-negative anaerobe bacteria bind the cobalamin-intrinsic factor complex, and bacterial overgrowth of the small intestine diminishes cobalamin resorption. Parasitic infections with fish tape-worm and Giardia lamblia are also associated with cobalamin malabsorption. The cobalamin-intrinsic factor complex binds to the ileal receptors in the terminal ileum. Cobalamin absorption may be impaired after resection or by diseases affecting more than 50 cm of the terminal ileum, such as Crohn's disease, coeliac disease, tuberculosis, lymphoma or radiation. There is clearly a wide diversity in the aetiology of cobalamin deficiency, which requires a versatile diagnostic approach.

Fecal excretion of radiolabeled (51CrCl3) proteins in patients with Crohn's disease

Intestinal leakage of plasma proteins was studied in 69 patients with Crohn's disease. In vivo labeling of plasma proteins was performed by intravenous injection of trace amounts of 51CrCl3. Complete fecal collection was done for 5 days, carefully avoiding contamination with urine. The daily fecal radioactivity was measured in a whole-body counter and expressed as a percentage of given dose. In patients with a classic localization of the disease the mean fecal excretion of radiolabeled proteins was 2.8% (range, 0.8-5.5%). The excretion was significantly higher in patients with extensive ileojejunal involvement (8.8%; 4.3-14.0%) and in patients with a total colitis (5.5%; 2.0-8.2%) but not different from that in patients with prestomal recurrent ileal disease (3.5%; 1.6-5.3%). A close correlation was found between fecal excretion of 51Cr and extent of the small-intestinal disease as measured at laparotomy (r = 0.86, p less than 0.001). A highly significant inverse relationship was also demonstrated between fecal protein excretion and serum albumin concentration in patients without septic complications of the disease (r = -0.57, p less than 0.001). A pre-existing septic complication made the patients hypoalbuminemic despite limited intestinal loss of protein. It is concluded that estimation of intestinal protein loss is a sensitive and simple test for assessment of the extent of the small-intestinal involvement in patients with Crohn's disease. The test may be of value in patients with unclear radiologic findings and in patients with hypoalbuminemia of unknown cause.

Nutritional management of inflammatory bowel disease

Malnutrition and growth failure are frequent complications of inflammatory bowel disease in childhood owing to inadequate dietary nutrient intakes, excessive intestinal losses, malabsorption, and increased nutrient requirements. Aggressive nutritional therapy is indicated for primary and supportive management of disease activity, drug nutrient interactives, individual nutrient abnormalities, and the overall complications of inflammatory bowel disease, malnutrition, and growth failure. The prevention of nutritional disorders in inflammatory bowel disease is accomplished by monitoring anthropometric and biochemical indices and by instituting appropriate enteral or parenteral nutritional therapy when indicated.

Relationship between clinical and laboratory parameters and length of lesion in Crohn's disease of small bowel

The correlation of 22 commonly used clinical and laboratory abnormalities with linear extent of the lesion was studied in 70 patients with Crohn's ileitis, 16 of whom had inactive disease and 54 active disease. Extent was measured radiologically using a well-validated double-contrast technique. In the patients with active disease, lesion length was significantly correlated with weight loss, serum albumin, total protein, and serum iron. In the group without active inflammation, pain and abdominal mass were significantly correlated with lesion extent. No correlation was found between linear extent of lesion and the following: an index of inflammatory activity (New Crohn's Disease Activity Index), several acute-phase reactants, and the components of the complete blood count. Only total protein and serum iron had a significant regression coefficient following a procedure of stepwise regression. No mathematical model was found capable of satisfactorily predicting the length of lesion.

Estimation of 14C-triolein assimilation as a test of lipid assimilation. Breath test or measurement of serum radioactivity?

Two tests of lipid assimilation based on estimation of 14C-triolein assimilation from expiratory 14CO2 (breath test) and from serum radioactivity of 14C, respectively, were investigated in 48 consecutive patients suspected of having malassimilation. Patients with proven malassimilation had significantly lower expiration of 14CO2 and lower serum radioactivity of 14C than patients with normal lipid assimilation. The se-14C test correctly diagnosed significantly more patients with malassimilation than the breath test; the diagnostic efficiencies were 0.87 and 0.74, respectively. The results of both tests correlated with measurement of faecal fat. However, within the group of patients with proven malassimilation the results of the breath test correlated poorly with faecal fat, whereas a significant correlation was found between the se-14C test and faecal fat within this group. Correspondingly, the correlation between the results of the breath test and the se-14C test was poor, indicating that intermediate metabolism influences the results.