Metabolic bone disease associated with total parenteral nutrition

Uncovering the Relationship Between Genes and Phenotypes Beyond the Gut in Microvillus Inclusion Disease

Microvillus inclusion disease (MVID) is a rare condition that is present from birth and affects the digestive system. People with MVID experience severe diarrhea that is difficult to control, cannot absorb dietary nutrients, and struggle to grow and thrive. In addition, diverse clinical manifestations, some of which are life-threatening, have been reported in cases of MVID. MVID can be caused by variants in the MYO5B, STX3, STXBP2, or UNC45A gene. These genes produce proteins that have been functionally linked to each other in intestinal epithelial cells. MVID associated with STXBP2 variants presents in a subset of patients diagnosed with familial hemophagocytic lymphohistiocytosis type 5. MVID associated with UNC45A variants presents in most patients diagnosed with osteo-oto-hepato-enteric syndrome. Furthermore, variants in MYO5B or STX3 can also cause other diseases that are characterized by phenotypes that can co-occur in subsets of patients diagnosed with MVID. Recent studies involving clinical data and experiments with cells and animals revealed connections between specific phenotypes occurring outside of the digestive system and the type of gene variants that cause MVID. Here, we have reviewed these patterns and correlations, which are expected to be valuable for healthcare professionals in managing the disease and providing personalized care for patients and their families.

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.

Glucagon-like peptide-2 analogues for Crohn’s disease patients with short bowel syndrome and intestinal failure

Short bowel syndrome (SBS) with intestinal failure (IF) is a rare but severe complication of Crohn’s disease (CD), which is the most frequent benign condition that leads to SBS after repeated surgical resections, even in the era of biologics and small molecules. Glucagon-like peptide-2 analogues have been deeply studied recently for the treatment of SBS-IF. These drugs have a significant intestinotrophic effect and the potential to reduce the chronic dependence of SBS-IF patients on parenteral support or nutrition. Teduglutide has been approved for the treatment of SBS-IF, and apraglutide is currently in clinical development. The use of these drugs was examined with a focus on their use in CD patients.

Metabolic Bone Disease in Children with Intestinal Failure and Long-Term Parenteral Nutrition: A Systematic Review

Metabolic bone disease (MBD) is a possible complication of intestinal failure (IF), with a multi-factorial pathogenesis. The reduction of bone density (BMD) may be radiologically evident before manifestation of clinical signs (bone pain, vertebral compression, and fractures). Diagnosis relies on dual-energy X-ray absorptiometry (DXA). Incidence and evolution of MBD are not homogeneously reported in children. The aim of this systematic review was to define the prevalence of MBD in IF children and to describe risk factors for its development. A comprehensive search of electronic bibliographic databases up to December 2021 was conducted. Randomized controlled trials; observational, cross-sectional, and retrospective studies; and case series published between 1970 and 2021 were included. Twenty observational studies (six case-control) were identified and mostly reported definitions of MBD based on DXA parameters. Although the prevalence and definition of MBD was largely heterogeneous, low BMD was found in up to 45% of IF children and correlated with age, growth failure, and specific IF etiologies. Data demonstrate that long-term follow-up with repeated DXA and calcium balance assessment is warranted in IF children even when PN dependence is resolved. Etiology and outcomes of MBD will be better defined by longitudinal prospective studies focused on prognosis and therapeutic perspectives.

A prospective case-control pilot study to evaluate bone microarchitecture in children and teenagers on long-term parenteral nutrition using HR-pQCT

Long-term parenteral nutrition (PN) may induce bone complications. Tridimensional bone imaging techniques such as high-resolution peripheral quantitative computed tomography (HR-pQCT) allow the assessment of both compartmental volumetric densities and microarchitecture. Our aim was to evaluate these parameters in children and teenagers receiving long-term PN. This cross-sectional, case–control study included children older than 9 years undergoing PN for at least 2 years. They were age-, gender- and puberty-matched with healthy controls (1:2). Evaluation included biological assessment of bone metabolism (serum calcium, phosphate, and albumin; urinary calcium and creatinine; 25-OH vitamin D, osteocalcin and PTH), dual X-ray absorptiometry (DXA) and HR-pQCT at the ultradistal tibia and radius. Results are presented as median [range]. Eleven patients (3 girls) with a median age of 16 [9–19] years were included. Bone parameters assessed by HR-pQCT at the ultradistal radius and tibia were similar in patients and controls. Parathyroid hormone (PTH) levels were higher (14 [7–115] vs 16 [12–27]) and osteocalcin levels were lower (44 [15–65] vs 65 [38–142]) in patients than in controls, although within the normal range. Conclusions: there were no differences for compartmental bone densities and microarchitecture in patients undergoing chronic PN. Further longitudinal studies are required to confirm these quite reassuring preliminary results.

Metabolic bone disease in children with intestinal failure is not associated with the level of parenteral nutrition dependency

BACKGROUND & AIMS

Children on long-term home parenteral nutrition (HPN) are at increased risk of suboptimal growth and metabolic bone disease (MBD) i.e. decreased bone mineral density (BMD). The aims of this cross-sectional study were to assess growth and bone health in children on long term HPN and to identify risk factors for MBD.

METHODS

Children above the age of 5 years, stable on HPN for more than 2 years were included. Medical files were reviewed retrospectively and included demographics, gestational age, birth weight and height, indication for PN, age at PN start, duration of PN, number of weekly PN infusions, weight-for-age and height-for-age (SD), body mass index (BMI, kg/m²) as well as blood and urine analyses at the time of Dual X-ray absorptiometry (DXA) measurements. All BMD values were adjusted to statural age which corresponds to the 50th percentile of height. Growth failure (height-for-age ≤ -2SD) and MBD (at least one BMD measurement ≤ -2SD) were analyzed according to the indication of PN, duration of PN and PN dependency index (PNDI) by comparing means and performing logistic regression analysis. PNDI is the ratio of non-protein energy intake in HPN to resting energy expenditure using Schofield equations.

RESULTS

Forty children were assessed at 12.4 ± 4.5 years of age. Mean age at PN start was 1.1 ± 3.6 y (median 0.5). The indications for PN were short bowel syndrome (SBS, n = 21), chronic intestinal pseudo-obstruction syndrome (CIPOS, n = 10) and congenital enteropathies (CE, n = 9). The mean number of PN perfusions was 6 ± 1/week. PNDI was 110 ± 30%. The mean serum level of 25-OHD3 was suboptimal at 26.5 ± 9.1 ng/mL (66.2 ± 22.8 nmol/L). The mean concentrations of calcium, phosphorus, and parathyroid hormone (PTH) were in the normal ranges. Eight children (20%) had PTH levels above normal with low 25-OHD3 levels. The mean weight-for-age and height-for-age Z-scores SDS were 0.4 ± 0.9 and -0.5 ± 1.1 respectively. The actual height was lower than genetic target height (p < 0.001). The BMD Z-scores, adjusted to the 50th percentile of height, of the spine, the left femur and the whole body were: -1.1 ± 1.7, -1.2 ± 1.5 and -1.5 ± 1.8 SDS respectively. Children with CE had significantly lower BMD values than those with SBS and CIPOS (p = 0.01). Only two children had bone fractures after a mild trauma (5%).

CONCLUSIONS

All children on long-term PN, are at risk of low BMD. High dependency on PN (PNDI>120%) and very long-term PN (>10 years) do not appear to increase the risk of growth failure nor MBD. PN-related bone fractures were rare. Close follow-up remains mandatory.

Macronutrients in Parenteral Nutrition: Amino Acids

The right amount and quality of amino acids (AAs) supplied to patients on parenteral nutrition (PN) reduces muscle mass loss, may preserve or even increase it, with significant clinical benefits. Several industrial PN mixtures are available so that nutrition specialists can choose the product closest to the patient's needs. In selected cases, there is the possibility of personalizing compounded mixtures in a hospital pharmacy that completely meets the individual nutritional needs of PN patients. This narrative review deals with the AA solutions used in PN mixtures. The physiology, the methods to calculate the AA needs, and the AA and energy requirements suggested by scientific guidelines for each patient type are also reported.

Bone Mineral Composition Among Long-Term Parenteral Nutrition Patients: Postmortem Assessment of Calcium, Phosphorus, Magnesium, and Select Trace Elements

BACKGROUND

Patients receiving long-term parenteral nutrition (PN) treatment are at risk of developing metabolic bone diseases (MBDs). The bone compartment serves as a repository for a range of metal(loid)s that are administered intravenously to patients via PN solutions. Thus, the mineral composition of patient bones may be linked to the development of MBDs in this group.

METHODS

We measured 12 elements in bone samples obtained post mortem from 7 long-term (2-21 years) PN patients and 18 control bones obtained from hip/knee replacement surgery. The samples were cleaned, digested, and subsequently analyzed using a method based on inductively coupled plasma tandem mass spectrometry.

RESULTS

Compared with the control group, bones obtained from PN patients were significantly (P < 0.05) depleted in calcium (Ca), phosphorus (P), magnesium (Mg), chromium, and strontium and enriched in manganese (Mn), zinc, barium, cadmium (Cd), and uranium (U). No differences were observed for cobalt or lead.

CONCLUSIONS

Depletion of major components of bone mineral (Ca, P, and Mg) and enrichment in known toxicants (Cd, Mn, U) are concerns for PN patients.

Effects of dietary omega-3 fatty acids on bones of healthy mice

BACKGROUND & AIMS

Altering the lipid component in diets may affect the incidence of metabolic bone disease in patients dependent on parenteral nutrition. Consumption of polyunsaturated fatty acids (PUFA) can impact bone health by modulating calcium metabolism, prostaglandin synthesis, lipid oxidation, osteoblast formation, and osteoclastogenesis. The aim of this study was to evaluate the dietary effects of PUFA on murine bone health.

METHODS

Three-weeks-old male (n = 30) and female (n = 30) C57BL/6J mice were randomized into one of three dietary groups. The diets differed only in fat composition: soybean oil (SOY), rich in ω-6 PUFA; docosahexaenoic acid alone (DHA), an ω-3 PUFA; and DHA with arachidonic acid, an ω-6 PUFA, at a 20:1 ratio (DHA/ARA). After 9 weeks of dietary treatment, femurs were harvested for micro-computed tomographic analysis and mechanical testing via 3-point bending. Separate mice from each group were used solely for serial blood draws for measurement of biomarkers of bone formation and resorption.

RESULTS

At the microstructural level, although some parameters in cortical bone reached differences that were statistically significant in female mice, these were too small to be considered biologically relevant. Similarly, trabecular bone parameters in male mice were statistically different in some dietary groups, although the biological interpretation of such subtle changes translate into a lack of effect in favor of any of the experimental diets. No differences were noted at the mechanical level and in blood-based biomarkers of bone metabolism across dietary groups within gender.

CONCLUSIONS

Subtle differences were noted at the bones' microstructural level, however these are likely the result of random effects that do not translate into changes that are biologically relevant. Similarly, differences were not seen at the mechanical level, nor were they reflected in blood-based biomarkers of bone metabolism. Altogether, dietary consumption of PUFA do not seem to affect bone structure or metabolism in a healthy model of growing mice.

Prediction of Renal Acid Load in Adult Patients on Parenteral Nutrition

Metabolic acidosis and metabolic bone disease are frequent complications in patients on parenteral nutrition (PN). A common contributor to these complications could be a daily high renal acid load. This study aims to find a method for predicting the potential total acid load (PTAL) and the pH of the compounded parenteral nutrition mixtures. The pH and titratable acidity (TA) of fifty compounded mixtures were measured. The potential metabolic acid load (PMAL) was calculated by considering the amount of nutrients that are acid producers and consumers. The PTAL of the TPN mixtures was calculated by adding TA to PMAL. Multiple linear regression analyses were used to develop a predictive model for the TA and pH of the compounded mixtures. The predicted TA and pH values of the analyzed mixtures agreed with those measured (Passing-Bablok analysis). The PTAL was >50 mmol/day for 82% of the mixtures, >75 mmol/day for 40% of the mixtures, and >100 mmol/day for 22% of the mixtures. The prediction of the renal acid load in patients on long-term PN could allow more appropriate acid-base balancing. Moreover, predicting the pH of such mixtures could be useful to pharmacists to assess the stability and compatibility of the components in the compounded mixtures.

Longitudinal Bone Mineralization Assessment in Children Treated With Long-Term Parenteral Nutrition for Severe Intestinal Failure

BACKGROUND

Metabolic bone disease is common in children receiving home parenteral nutrition (HPN) for intestinal failure (IF). Long-term evolution of bone mass in pediatric IF is poorly documented. The aims of this study were (1) to determine the prevalence of low bone mass (LBM) in children receiving HPN for IF, (2) to evaluate the evolution of total bone mineral content (TBMC) during HPN with dual-energy x-ray absorptiometry (DXA), and (3) to identify related factors.

METHODS

All children referred in our HPN center from 2004 to 2014 were eligible. Inclusion criteria were HPN dependence due to noninflammatory IF, at least 2 TBMC assessments, and HPN duration of at least 2 years at last DXA. TBMC was expressed in z score for ideal weight for height (WFH). LBM was defined by a TBMC WFH z score ≤-2 standard deviations (SD).

RESULTS

A total of 175 DXAs for 31 children were performed, mean of 5.6 ± 2.9 assessments per child. The median time between first and last DXA recorded was 6.2 years (0.7-16.6). At the first DXA, 14 children (45%) had a LBM. TBMC increased by +0.1 ± 0.04 SD per year of HPN (P = .012). The risk of LBM decreased with an odds ratio of 0.9 per year of HPN (95% confidence interval, 0.92-0.99; P = .018). Lean mass z score and calcium parenteral intakes were related to the TBMC improvement.

CONCLUSION

LBM is common in pediatric IF, but bone status could improve during HPN in these children.

Interplay between bone and incretin hormones: A review

Bone is a tissue with multiple functions that is built from the molecular to anatomical levels to resist and adapt to mechanical strains. Among all the factors that might control the bone organization, a role for several gut hormones called "incretins" has been suspected. The present review summarizes the current evidences on the effects of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) in bone physiology.

Principles and Strategies for Monitoring Home Parenteral Nutrition

Patients who cannot ingest adequate calories to maintain body weight via their gastrointestinal tract may require parenteral nutrition (PN) at home. As with any therapy, the patient must be evaluated to determine if the home PN (HPN) is effective and the patient is free of complications. This review discusses specific items to monitor for HPN patients. Parameters to monitor can be divided into those used to determine effectiveness and those used to prevent complications of HPN. In addition, potential HPN-associated complications can be divided into those that occur with short- or long-term PN administration. Specific items to monitor are discussed within this framework.

Home Care Management of Intestinal Transplant Recipients

During the past 14 years, significant advances have been made in the field of intestinal transplantation. Patients' survival rates have increased, influencing referral patterns, and there has been a growing trend toward shortened hospitalizations with earlier discharge. Home care has also evolved during this same period, with development of the resources, training, and processes required for in-home management of patients with multiple complex needs. Together these trends have led to the ability to provide care and services to higher acuity patients in the outpatient and home setting after intestinal transplantation. In this article, we review the infusion management of intestinal transplant recipients before and after they go home and the rationale for the need for specialized home care services.

Management and Complications of Short Bowel Syndrome: an Updated Review

Short bowel syndrome (SBS) is defined as loss of bowel mass from surgical resection, congenital defects, or disease. Intestinal failure (IF) includes the subset of SBS unable to meet nutrition needs with enteral supplements and requires parenteral nutrition (PN). The parenteral treatment of SBS is now a half-century old. Recent pharmacologic treatment (GLP-2 analogues) has begun to make a significant impact in the care and ultimate management of these patients such that the possibility of reducing PN requirements in formerly PN-dependent patients is a now a real possibility. Finally, newer understanding and possible treatment for some of the complications related to IF have more recently evolved and will be an emphasis of this report. This review will focus on developments over the last 10 years with the goal of updating the reader to new advances in our understanding of the care and feeding of the SBS patient.

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.

Treatment with pamidronate for osteoporosis complicating long-term intestinal failure

Long-term home parenteral nutrition (PN) is a potential risk for developing osteoporosis. Various attempts have been made to treat bone disease both by modifying the composition of PN and by administering hormones, such as calcitonin, parathyroid hormone, and sexual hormones. Bisphosphonates are recognized as a medication useful for the treatment of several bone disorders associated with excessive reabsorption. Nevertheless, there have been no paediatric studies on bisphosphonates use for intestinal failure-associated bone disease. Our study includes 6 paediatric patients receiving extremely long-term home PN (at least 3 years) who showed radiological and clinical signs of osteoporosis. Diagnosis of bone disease was made after a median period of 127.5 PN months. Treatment consisted in 2 cycles of intravenous pamidronate, 30 mg/m once per month for 6 months consecutively. They all showed a significant improvement in bone mineral density, evaluated after 6 and 12 months of pamidronate treatment. In our sample anthropometrical variables (weight, height, and body mass index) are not related with the z-score trend. Our patients had normal levels of calcium, phosphorus, and vitamin D, and proper nutrient intake. At the last follow-up, dual-energy x-ray absorptiometry scan showed that no patients had a z-score lower than -2.5; moreover, nobody developed bone fractures during the 108-month follow-up. The patients did not have any prominent adverse effect. Finally, in our experience, pamidronate is effective for improving bone mineral density and safe in patients with intestinal failure-associated bone disease.

Effects of 17β-estradiol and vitamin E treatments on blood trace element and antioxidant enzyme levels in ovariectomized rats

We investigated the effect of 17β-estradiol (E(2)) alone and separately vitamin E treatment on trace element status of rats following an ovariectomic operation. Forty rats were equally divided into four groups: Group 1, control, non-ovariectomized rats; Group 2, (OVX) rats, ovariectomized under general anesthesia; Group 3, (OVX+E(2)) rats, the group received a 40 µg kg(-1) subcutan dose of E(2) per day after ovariectomy; and Group 4, (OVX + E(2) + vitamin E) rats, received the same E(2) treatment, but with an additional 100 mg kg(-1) intraperitoneal dose of vitamin E per day after ovariectomy. At the end of the 30-day experiment, the rats were sacrificed and their blood was collected for the measurement of zinc, copper, iron, phosphorus, selenium, magnesium, calcium, manganese, and chromium; copper-zinc superoxide dismutase (SOD); manganese-superoxide dismutase (Mn-SOD); glutathione peroxidase (Se-GSH-Px); and catalase (CAT). The levels of zinc, copper, iron, phosphorus, selenium, calcium, chromium, and manganese and activities of SOD, Mn-SOD, Se-GSH-Px, and CAT were lower in the OVX than in the control group, but magnesium level was unaffected. However, zinc, copper, iron, phosphorus, selenium, calcium, chromium, and manganese levels and SOD, Mn-SOD, Se-GSH-Px, and CAT activities were higher under separate E(2) and E(2) + vitamin E treatments. The level of magnesium in the treated-OVX groups was not different than in the OVX group. In conclusion, E(2) treatment has an ameliorating effect on the trace element status in OVX, and this effect may be enhanced with the addition of vitamin E.

How does long-term parenteral nutrition impact the bone mineral status of children with intestinal failure?

Patients on long-term parenteral nutrition (PN) are at significantly increased risk for the development of metabolic bone disease (MBD); this condition is characterized by incomplete mineralization of osteoid with consequent disturbances ranging from osteopenia to severe bone disease with fractures. The aim of the study was: (1) to evaluate the prevalence of MBD, (2) to identify the PN- or intestinal failure (IF)-related factors and (3) to assess annual changes of bone mineral status. Since September 2005 all patients affected by IF and treated with PN started a BMD evaluation program using dual-energy X-ray absorptiometry (DXA). Twenty-four IF patients were included [15 with short bowel syndrome (SBS), 5 with severe protracted diarrhea and 4 with chronic intestinal pseudostruction]. The bone mineral density (BMD) Z-score was significantly lower in patients than in the control group. In our series SBS patients showed a BMD Z-score significantly higher in comparison with the medical causes of IF. No significant correlations were found between bone mineral status and PN duration and nutrient intake. Nine IF patients were submitted to a second DXA evaluation after 1 year from the baseline. All bone mineral variables were significantly increased at the second DXA evaluation. The high prevalence of MBD in IF patients undergoing long-term treatment with PN requires that these patients undergo careful and periodic monitoring of their bone mineral status; patients with congenital gut dysfunctions, such as epithelium defects and motility anomalies, are at major risk of developing this complication, probably due to the association with extra-intestinal causes of bone loss.

Role of vitamin D in adults requiring nutrition support

The major and most well-known function of vitamin D is to maintain calcium and phosphorus homeostasis and promote bone mineralization. However, recent evidence suggests that vitamin D may be important for a variety of nonskeletal outcomes. The review synthesizes the available evidence for the role of vitamin D in skeletal health as well as its novel roles in medical conditions such as muscle function, falls, immunity, glucose homeostasis, and cardiovascular diseases. The article reviews methods for assessing vitamin D status and suggests strategies to restore vitamin D status in patients requiring enteral or parenteral nutrition who are at particularly high risk of hypovitaminosis D. Screening for hypovitaminosis D with plasma total 25-hydroxyvitamin D should be a routine part of the care of the patient requiring enteral or parenteral nutrition. Restoration of optimal vitamin D status with high-dose supplemental vitamin D is required in most cases, whereas exposure to sunlight or an ultraviolet B radiation-emitting device is most effective in patients with severe malabsorption or those requiring long-term parenteral therapy. Given the emerging role of vitamin D for a variety of acute and chronic conditions, the optimal vitamin D status in acutely ill patients as well as in patients requiring long-term nutrition therapy warrants further investigation.

ESPEN Guidelines on Parenteral Nutrition: home parenteral nutrition (HPN) in adult patients

Home parenteral nutrition (HPN) was introduced as a treatment modality in the early 1970s primarily for the treatment of chronic intestinal failure in patients with benign disease. The relatively low morbidity and mortality associated with HPN has encouraged its widespread use in western countries. Thus there is huge clinical experience, but there are still few controlled clinical studies of treatment effects and management of complications. The purpose of these guidelines is to highlight areas of good practice and promote the use of standardized treatment protocols between centers. The guidelines may serve as a framework for development of policies and procedures.

Short bowel syndrome: parenteral nutrition versus intestinal transplantation. Where are we today?

Current management of short bowel syndrome (SBS) revolves around the use of home TPN (HPN). Complications include liver disease, catheter-related infections or occlusions, venous thrombosis, and bone disease. Patient survival with SBS on TPN is 86% and 75% at 2 and 5 years, respectively. Surgical management of SBS includes nontransplant surgeries such as serial transverse enteroplasty and reanastomosis. Small bowel transplant has become increasingly popular for management of SBS and is usually indicated when TPN cannot be continued. Posttransplant complications include graft-versus-host reaction, infections in an immunocompromised patient, vascular and biliary diseases, and recurrence of the original disease. Following intestinal-only transplants, patient and graft survival rate is 77% and 66% after 1 year. After 5 years the survival figures are 49% and 34%, respectively. Future improvements in survival and quality of life will enhance small bowel transplant as a viable treatment option for patients with SBS.

Fluoride exposure and bone status in patients with chronic intestinal failure who are receiving home parenteral nutrition

BACKGROUND AND OBJECTIVE

Metabolic bone disease is frequent in chronic intestinal failure. Because fluoride has a major effect on bones, the status of both fluoride and bone was studied in long-term home parenteral nutrition (HPN) patients.

DESIGN

We studied 31 adults aged (x +/- SD) 56.3 +/- 15.1 y, mainly patients with short-bowel syndrome, who had been receiving HPN for >1 y. Bone mineral density (BMD) was measured by absorptiometry, and serum fluoride was measured by using a fluoride-sensitive electrode. All patients ate and drank ad libitum. HPN (3.4 +/- 1.2 times/wk) complemented oral nutrition. Potential explicative factors were estimated by using a linear regression model (mixed-effects model).

RESULTS

Of 120 fluoride dosages (2-6/patient), 102 were above the upper normal limit (1.58 micromol/L) at the laboratory. Mean (+/- SD) daily fluoride supply was 8.03 +/- 7.71 mg (US adequate intake: 3.1 mg/d for women and 3.8 for men; tolerable upper normal limit: 10 mg/d); intravenous fluoride varied from 0.06 to 1.45 mg, and oral fluoride varied from 0.09 to 27.8 mg. Serum fluoride concentrations were correlated with creatinine clearance and fluoride supply. BMD was significantly lower in the femoral neck than in the spinal area. After adjustment for sex and the duration of HPN, only the effect of serum fluoride on spinal BMD was significant. Two patients had symptoms of fluorosis, eg, calcaneum fissures, interosseous calcifications, or femoral neck osteoporosis.

CONCLUSIONS

In chronic intestinal failure, high intakes of fluoride are frequent because of the beverages ingested to compensate for stool losses. Hyperfluoremia has an effect on bone metabolism and may increase skeletal fragility. The consumption of fluoride-rich beverages for extended periods is therefore not advisable.

Osteoporosis in children and adolescents: etiology and management

Bone mass increases progressively during childhood, but mainly during adolescence when approximately 40% of total bone mass is accumulated. Peak bone mass is reached in late adolescence, and is a well recognised risk factor for osteoporosis later in life. Thus, increasing peak bone mass can prevent osteoporosis. The critical interpretation of bone mass measurements is a crucial factor for the diagnosis of osteopenia/osteoporosis in children and adolescents. To date, there are insufficient data to formally define osteopenia/osteoporosis in this patient group, and the guidelines used for adult patients are not applicable. In males and females aged <20 years the terminology 'low bone density for chronologic age' may be used if the Z-score is less than -2. For children and adolescents, this terminology is more appropriate than osteopenia/osteoporosis. Moreover, the T-score should not be used in children and adolescents. Many disorders, by various mechanisms, may affect the acquisition of bone mass during childhood and adolescence. Indeed, the number of disorders that have been identified as affecting bone mass in this age group is increasing as a consequence of the wide use of bone mass measurements. The increased survival of children and adolescents with chronic diseases or malignancies, as well as the use of some treatment regimens has resulted in an increase in the incidence of reduced bone mass in this age group. Experience in treating the various disorders associated with osteoporosis in childhood is limited at present. The first approach to osteoporosis management in children and adolescents should be aimed at treating the underlying disease. The use of bisphosphonates in children and adolescents with osteoporosis is increasing and their positive effect in improving bone mineral density is encouraging. Osteoporosis prevention is a key factor and it should begin in childhood. Pediatricians should have a fundamental role in the prevention of osteoporosis, suggesting strategies to achieve an optimal peak bone mass.

Parenteral nutrition-associated liver disease and the role for isolated intestine and intestine/liver transplantation

Parenteral nutrition-associated liver disease (PNALD) is the most devastating complication of long-term parenteral nutrition therapy. Because its progression is typically insidious and its long-term consequences are generally underappreciated, PNALD is often recognized too late, when liver injury is irreversible. When end-stage liver disease (ESLD) develops in these patients, most potential interventions are futile and transplantation of both an intestine and a liver becomes the only viable option, despite the relatively poor outcomes associated with this combined procedure. Although likely multifactorial in origin, the etiology of PNALD is poorly understood. Early clinical intervention with a combination of nutritional, medical, hormonal, and surgical therapies can be effective in preventing liver disease progression. If these interventions fail, intestinal transplantation should be performed expeditiously before development of ESLD mandates simultaneous inclusion of a liver graft as well.

Bone mineral density in patients on home parenteral nutrition: a follow-up study

BACKGROUND AND AIMS

The variations of bone mineral density (BMD) during home parenteral nutrition (HPN) and their relationship with general, life style, primary disease and HPN risk factors were investigated by a follow-up study.

DESIGN

Patients who had BMD assessment in a previous cross-sectional survey underwent a 2nd BMD at femoral neck (FN) and lumbar spine (LS). Data about risk factors were collected by a structured questionnaire. BMD Z-score (number of standard deviations from normal values corrected for sex and age) and the annualized percent BMD change were analysed.

RESULTS

Sixty-five adult patients were enrolled (follow-up: 18.1+/-5.5 months). The mean BMD Z-score significantly increased at the LS (P = 0.040) and remained unchanged at FN. In multiple regression analysis, the variations of the LS Z-score during HPN negatively correlated with the female sex (P = 0.021) and the age at starting HPN (P = 0.022). The analysis of the annualized percent BMD change confirmed the results obtained by the analysis of the Z-score. No factor was associated with BMD variation at FN.

CONCLUSIONS

HPN was not associated with a decrease of BMD in most of the patients; LS BMD Z-score variations were related to general risk factors rather than to HPN factors, showing a negative association with age and female sex.

Home care management of intestinal transplant recipients

During the past 14 years, significant advances have been made in the field of intestinal transplantation. Patients' survival rates have increased, influencing referral patterns, and there has been a growing trend toward shortened hospitalizations with earlier discharge. Home care has also evolved during this same period, with development of the resources, training, and processes required for in-home management of patients with multiple complex needs. Together these trends have led to the ability to provide care and services to higher acuity patients in the outpatient and home setting after intestinal transplantation. In this article, we review the infusion management of intestinal transplant recipients before and after they go home and the rationale for the need for specialized home care services.

Osteoporosis in patients on long-term home parenteral nutrition: a longitudinal study

The prevalence of osteoporosis was investigated in 88 patients with intestinal failure (IF). Osteoporosis was found in 67%, dependent of body mass index and age when IF occurred. In 56 patients on HPN, followed prospectively, changes in bone density were dependent on the duration of HPN; older patients had a higher increase.

INTRODUCTION

It has been suggested that low bone mass and negative bone balance may occur in adult patients receiving home parenteral nutrition (HPN). The aim of this study was to assess prospectively the prevalence of osteoporosis in intestinal failure (IF) patients and the changes in bone mineral density in those on long-term HPN and to analyze the factors that may influence the occurrence and evolution of osteoporosis.

MATERIALS AND METHODS

Bone mineral density was measured at the lumbar spine and femoral neck in 88 IF patients.

RESULTS

At the first bone mineral density determination (baseline), the prevalence of osteoporosis was 67% in this population (median age, 52 years). Ten percent of the patients with osteoporosis experienced fragility fractures. Osteoporosis was independent of age and gender but occurred earlier in patients who had received corticosteroids. At baseline, the lumbar Z-score was positively correlated mainly to body mass index and age when IF occurred; these two parameters explained 34% of the Z-score. Repeated measurements were performed in 56 patients during long-term HPN (mean duration, 5.5 +/- 1.2 years). The changes in Z-score at the lumbar spine were dependent on the age when IF occurred and on the duration of HPN, with a synergistic effect between them. The older the patients, the higher the increase in Z-score during HPN.

CONCLUSION

HPN had no deleterious effect on cortical bone and actually improved trabecular bone in patients whose intestinal disease started after the age of 21 years.

Effect of cyclical intravenous clodronate therapy on bone mineral density and markers of bone turnover in patients receiving home parenteral nutrition

BACKGROUND

Patients receiving home parenteral nutrition (HPN) because of intestinal failure are at high risk of developing osteoporosis.

OBJECTIVE

We studied the effect of the bisphosphonate clodronate on bone mineral density (BMD) and markers of bone turnover in HPN patients.

DESIGN

A 12-mo, double-blind, randomized, placebo-controlled trial was conducted to study the effect of 1500 mg clodronate, given intravenously every 3 mo for 1 y, in 20 HPN patients with a bone mass T score of the hip or lumbar spine of less than -1. The main outcome measure was the difference in the mean percentage change in the BMD of the lumbar spine measured by dual-energy X-ray absorptiometry. Secondary outcome measures included changes in the BMD of the hip, forearm, and total body and biochemical markers of bone turnover, ie, serum osteocalcin, urinary pyridinoline, and urinary deoxypyridinoline.

RESULTS

The mean (+/-SEM) BMD of the lumbar spine increased by 0.8 +/- 2.0% in the clodronate group and decreased by 1.6 +/- 2.0% in the placebo group (P = 0.43). At all secondary skeletal sites (ie, hip, total body, and distal forearm), we observed no changes or small increases in the BMD of the clodronate group and decreases in the BMD of the placebo group. In the clodronate group, biochemical markers of bone resorption decreased significantly (P < 0.05).

CONCLUSIONS

Clodronate significantly inhibits bone resorption as assessed by changes in biochemical markers of bone turnover. Although the mean BMD increased in the clodronate group, cyclic clodronate therapy failed to increase spinal BMD significantly at 12 mo.

Prevalence of bone disease in patients on home parenteral nutrition

BACKGROUND & AIMS

The epidemiology of bone disease in home parenteral nutrition (HPN) is unknown. The aim of this paper is to evaluate the prevalence and severity of reduced bone mineral density (BMD) in long-term HPN.

DESIGN

Cross-sectional, multicentre study including patients who within the last 12 months had their BMD assessed by dual-energy-X-ray absorptiometry after at least 6 months of HPN. Data on bone pain and fractures, the primary gastrointestinal diseases, nutritional and rehabilitation status and HPN regimen were reviewed. Both the T-score (no. of SD below mean BMD of young subjects) and the Z-score (no. of SD from normal BMD values corrected for sex and age) were analysed.

RESULTS

A T -score <-1 at any site of assessment was observed in 84% of the 165 patients enrolled (<or= -2.5 in 41%). Bone pain occurred in 35% and bone fracture in 10% of patients. Both T - and Z-scores were significantly lower in symptomatic patients. The frequency of bone disease was higher in post-menopausal women but did not differ among the subgroups of the primary diseases. Stepwise regression analysis showed the lumbar spine Z -score positively associated with the age at starting HPN and the femoral neck Z-score positively associated with the body mass index.

CONCLUSIONS

Bone disease was present in most of the patients on HPN, was of severe degree in one-half of them and symptomatic in one-third. The BMD Z-score appeared predictive of the risk of fracture. The prevalence of bone disease did not differ between the various primary diseases. Age at starting HPN and body mass index appeared to be the major factors associated with BMD Z-scores.

Phosphate supplementation for hypophosphataemia and parenteral nutrition

Routine detection and treatment of acute hypophosphataemia is important in intensive care unit and many other hospitalized patients, but metabolic bone disease and hypophosphataemia are still experienced as a result of parenteral nutrition. A significantly common problem that faces the compounding pharmacist when formulating parenteral nutrition regimens is the difficulty associated with the successful avoidance of calcium phosphate precipitation. Although incorporation of the normal calcium and phosphate requirements into regimens for metabolically stable adults is usually achievable, it can prove impossible in paediatric and neonatal mixtures when using the standard inorganic sources that are currently licensed for use in the UK and USA. In other countries, where organic compounds are routinely available, this problem does not exist.