Oxalate metabolism after intestinal bypass operations

Hyperoxaluria and kidney stones are frequent following intestinal bypass operations. The urinary oxalate excretion was studied for 10-13 days during enteral and parenteral nutrition in six patients operated on because of massive obesity with a jejunoileostomy. The oxalate excretion in urine was higher than normal in all patients on normal diet. The excretion decreased on low-oxalate diet. Further decrease was observed during total parenteral nutrition (TPN). The oxalate excretion was stabilized at a low level within 48 h after the start of TPN and was unchanged during the rest of the study. This included a period of 2 days when a load of the oxalate precursor glycine (10 and 20 g) was given parenterally to five patients, resulting in increased serum glycine concentration. A slight decrease in oxalate excretion was found when the amino acid part (Vamin with 10% glucose) of the TPN solution was given enterally instead of parenterally in two patients. This study has indicated that the main reason for hyperoxaluria in patients with intestinal bypass operations is hyperabsorption of dietary oxalate. It seems likely that these patients have a normal endogenous oxalate production.     

Oxalate metabolism in man studied during total parenteral nutrition

The mean urinary excretion of oxalate was 325 micromol/24 h in six patients during total parenteral nutrition (TPN). The urinary excretion of oxalate was considered to be equal to the endogenous oxalate production. A 2-day load of the oxalate precursor glycine given to five patients did not influence the oxalate excretion in spite of increased serum glycine concentrations. A 3-day load of the oxalate precursor ascorbic acid given to four patients increased the oxalate excretion in all patients. In one patient TPN was prolonged for 20 days without any change in the amount of oxalate excreted.     

The effect of clindamycin on the intestinal flora in patients with enteric hyperoxaluria

Enteric hyperoxaluria is due to increased absorption of oxalate, especially in the colon. However, this mechanism is not fully understood. Little is also known about the composition of the intestinal flora in these patients. Eleven patients with hyperoxaluria (greater than 0.45 mmol/24 h) after jejunoileal bypass were therefore studied under surgical ward conditions for 5 days. The patients were maintained on a constant diet. During days 3, 4, and 5 clindamycin (Dalacina), 1.8 g/24 h, was given parenterally in three divided doses. All patients had hyperoxaluria, with a mean oxalate absorption of 0.94 +/- 0.09 mmol/24 h (+/- SEM). No significant disturbances in the colonic microflora were found. The degree of hyperoxaluria did not change during clindamycin administration, in spite of a significant decrease in the number of anaerobic bacteria. Our patients with enteric hyperoxaluria seem to have a normal colonic microflora. The degree of hyperoxaluria did not seem to be related to changes in the intestinal anaerobic flora.     

心脏移植患者24例的早期肠内营养支持应用

目的 探讨肠内营养在心脏移植中的作用。方法 我院原位异体心脏移值患者24例,将术前3 d,术后7、14、21以及28 d的营养相关指标进行比较,以此评价营养支持的效果。术前给予低钠饮食,部分营养状况较差的患者可辅以静脉营养;术后1~5 d采用全流食,辅以静脉营养;术后6~10 d逐渐过渡到全肠内营养,使用半流食和软食;术后12~18 d完全进食普食。结果 术后患者恢复良好,营养相关指标血清蛋白在术后1周明显下降,与术前相比,差别有统计学意义（P<0.05）,术后3周恢复至术前水平。结论 术前给予合理的营养支持可提高手术耐受力。术后视心脏功能恢复程度,给予合理的营养支持方法及营养素供给量利于心脏移植患者的恢复。     

Long-term outcome of severe radiation enteritis treated by total parenteral nutrition

The outcome of 31 patients with severe radiation enteritis treated by total parenteral nutrition (TPN) was analyzed. Before initiation of parenteral nutrition, 18 of the patients had not had abdominal surgery, while 13 had either a resection or an intestinal bypass for radiation enteritis. Median follow-up was 2 1/2 years (range: 1 month to 12 years) from the time of initiation of parenteral nutrition. Surgery was required in 15 cases because parenteral alimentation could not be continued. Only eight of these 15 were able to resume a normal oral intake. Total parenteral nutrition allowed oral feeding to be resumed in 11 (36%) after a median follow-up of 40 months (range: 6-142 months). In general, total parenteral nutrition was well tolerated and was associated with low morbidity. Eighteen patients died, 13 of complications due to radiation therapy, four of cancer recurrence, and one of an unrelated cause. Survival probability was 58% at one year and 36% at five years. When possible, prognostic factors present either before or at initiation of total parenteral nutrition were analyzed. Age, predisposing vascular factors (hypertension, diabetes mellitus, or vascular disease), and enteric fistula and/or perforation were found to have prognostic value. The probability of clinical radiation enteritis recurrence was 34% at one year and 47% at two years. A clinical recurrence of symptoms was more frequent but not significantly so after parenteral nutrition as compared to surgical therapy of radiation enteritis. Although TPN corrected denutrition and allowed deferred surgery in some patients, severe radiation enteritis remains a poorly predictable progressive disease with numerous relapses.     

Altered fractional excretion of uric acid during total parenteral nutrition

The presence of crystal proven podagra coincident with a 52% decrease in plasma urate after a 3-day course of total parenteral nutrition (TPN) prompted a study of urate excretion in 9 patients with Crohn's disease. By Day 9 in those receiving TPN, plasma urate decreased 58% (p less than 0.001), while fractional urate excretion increased 94% (p less than 0.005). Twenty-four hour urate excretion and serum creatinine were not significantly altered. These findings persisted for the duration of TPN. In 2 patients with ileocolitis, the addition or deletion of either lipid emulsion or multivitamin infusions during TPN had no effect on urate values. Rather, the amino acid load or a specific constituent appears to be the causal factor. These data suggest that hypouricemia due to extensive net urate excretion is common during TPN therapy. Finally, patients with established gout may be at risk for acute gouty attacks during TPN therapy.     

Temporal profiles of urinary excretion of NH2-terminal big gastrin immunoreactivity in humans

We studied the temporal profile of urinary NH2-terminal big gastrin immunoreactivity (NT G-34-IR) excretion in order to evaluate the dynamics of gastrin secretion. The temporal profile of urinary NT G-34-IR excretion in normal subjects represented three peaks corresponding to each meal. In contrast, the profile in antrectomized patients and patients under total parenteral nutrition (TPN) represented a flat pattern. Urinary NT G-34-IR excretions during fasting 2-h periods in antrectomized patients and TPN patients were about one-sixth and one-third, respectively, of basal NT G-34-IR excretion in normal subjects (53.1 +/- 13.9 pmol/h). Total urinary NT G-34-IR excretion during 24 h both in antrectomized patients (220 +/- 35 pmol/24 h) and TPN patients (390 +/- 68 pmol/24 h) was also significantly lower than in normal subjects (1985 +/- 403 pmol/24 h). The present study showed that the main source of urinary NT G-34-IR is the gastric antrum, that the main factor fluctuating its excretion is food intake, and that long-term TPN reduces basal gastrin secretion. Urinary NT G-34-IR would be a useful indicator for total gastrin secretion.     

Hepatobiliary, renal and bone complications of intestinal failure

Abnormal liver function tests in patients with intestinal failure (IF) may be due to the underlying disease, IF or the treatments given (including parenteral nutrition (PN)). PN-related liver disease in children usually relates to intrahepatic cholestasis and in adults to steatosis. Steatosis may be consequent upon an excess of carbohydrate, lipid or protein, or upon a deficiency of a specific molecule. Pigment-type gallstones are common in adults and children with IF; these develop from biliary sludge that forms during periods of gallbladder stasis. Ileal disease/resection, parenteral nutrition, surgery, rapid weight loss and drugs all increase the risk of developing gallstones. Gallstone formation may be prevented by reducing gallbladder stasis (oral/enteral feeding or prokinetic agents), altering bile composition, or by means of a prophylactic cholecystectomy. Calcium oxalate renal stones are common in patients with a short bowel and retained functioning colon and are consequent upon increased absorption of dietary oxalate; they are prevented by a low-oxalate diet. An osteopathy may occur with long-term parenteral nutrition.     

Urinary excretion and blood concentrations of trace elements and electrolytes during total parenteral nutrition in crohn's disease

Urinary excretion of trace elements (Cr, Co, Cu, Fe, Mn, Se, Zn, Sb, Cs, Rb), electrolytes (Na, K, Ca, Mg, phosphate), and nitrogen were determined during days 1–5 and 54–79 of total parenteral nutrition (TPN, nil per os) given to six patients with Crohn's disease. Whole-blood concentrations of Cr, Fe, Zn, Cs, and Rb and serum concentrations of electrolytes were determined before the TPN and on days 54–79 of TPN. The 24-hr urinary excretion of zinc was lower on days 54–79 than on days 1–5, but the rates of excretion of the other essential trace elements during TPN displayed no significant change. The urinary excretion of Cu, Fe, and Mn was numerically lower than the intravenous administration of these elements during days 1–5 and 54–79 of TPN, whereas the urinary excretion of zinc was lower than the supply only during days 54–79. The whole-blood concentration of zinc was low but constant during TPN, whereas the initially low levels of Cr and Fe were normalized on days 54–79. The results suggest that the supply of the essential trace elements Cr, Co, Cu, Fe, Mn, and Zn was largely adequate during two to three months of TPN and that the human body may adapt to a somewhat low supply of zinc, 20–30 mol/24 hr.     

Partial substitution of amino acids of a parenteral solution with tripeptides: Effects on parameters of protein nutrition in baboons

We previously showed that triglycine and trileucine are efficiently utilized when infused intravenously (IV) in baboons who are fed a complete diet orally. In the present experiments we investigated the utilization of these tripeptides in the context of total parenteral nutrition. A group of subhuman primates (baboon) was subjected sequentially to two forms of total parenteral nutrition, each for a period of six days. The only difference between the two periods was that in one, all amino acids were given in free form, and in the other, the glycine and leucine components of the amino acid mixture were replaced with triglycine and trileucine, respectively. During both experimental periods the infusion solution provided daily 100 calories/kg body weight and 2.5 g amino acids/kg body weight. There were no significant differences between nitrogen balance, plasma amino acid concentrations, or urinary excretion of amino acids for the two forms of parenteral nutrition. The only exceptions were a greater plasma concentration of isoleucine and a greater urinary excretion of leucine during infusion of the partial peptide solution. Assimilation of triglycine and trileucine under the conditions of total parenteral nutrition was assessed by determining concentrations of these peptides in plasma and urine. Trileucine was not found in plasma, and only 1.8% of the amount of trileucine infused appeared as trileucine and dileucine in urine. Triglycine was detected in plasma and 17.1% of the amount of triglycine infused was excreted in urine as triglycine and diglycine. These data suggest that assimilation of trileucine and triglycine under the conditions of our experiment was sufficiently efficient to meet the daily need for an essential amino acid (leucine) and for nitrogen (glycine).     

Utilization of intravenously infused tripeptides in baboons: Effect on plasma concentration and urinary excretion of amino acids

When baboons, while consuming an adequate diet, were infused continuously for 3 days with parenteral solutions (1l/day) containing either triglycine (50 mM) or trileucine (5 mM) there was either no or very little accumulation of these peptides either in plasma or urine. The increases in plasma concentrations of glycine or leucine and urinary excretion rates of these amino acids during the infusion of the above tripeptides were similar to those found when baboons were infused with parenteral solutions containing either glycine (150 mM) or leucine (15 mM). These data show efficient utilization of tripeptides under the condition of continuous infusion and encourage further investigation of tripeptides as substrates for parenteral nutrition.     

Decreased brush border hydrolase activities without gross morphologic changes in human intestinal mucosa after prolonged total parenteral nutrition of adults

Animal experimentation with total parenteral nutrition (TPN) has revealed the occurrence of atrophy of the intestinal mucosa and decreased enzyme activities of the brush border, notably the disaccharidases. These findings have heretofore not been confirmed in human investigation. We performed endoscopic biopsies in the third part of the duodenum in 7 adults before TPN, after 21 days of TPN, and after a progressive oral refeeding. We noted a clear-cut decrease of major enzyme activities during TPN (sucrase, maltase, lactase, glucoamylase, acid aminopeptidase, dipeptidyl peptidase) without any morphologic modifications as observed with standard histology. Electron microscopy showed a slight but significant decrease in the height of microvilli. The decreased enzyme activities were rapidly restored after oral refeeding. Thus, the functional consequences of the modifications observed during medium-term TPN in adults are probably limited.     

Determination of serum apo A-IV concentration in patients receiving total parenteral nutrition

Serum apolipoprotein (apo) A-IV levels were determined in patients receiving total parenteral nutrition (TPN) by an immunoassay using a specific antiserum against apo A-IV purified from human sera. The value was significantly lower than that of normal subjects (p less than 0.001), and the level correlated significantly with the duration of TPN. In a patient receiving TPN, serum apo A-IV concentration decreased during TPN and returned to normal levels after resuming oral intake of diet. This finding indicates that serum apo A-IV is a new parameter for nutritional assessment, since the protein is exclusively synthesized in the gut, being different from other rapid turnover proteins which are mainly synthesized in the liver.     

Beneficial effects of insulin-like growth factor I on epithelial structure and function in parenterally fed rat jejunum

BACKGROUND & AIMS: The functional significance of intestinal hyperplasia stimulated by insulin-like growth factor (IGF)-I is unclear and has not been studied in a model of mucosal atrophy induced by total parenteral nutrition (TPN). The aim of this study was to determine how IGF-I affects intestinal structure and epithelial function in the absence of luminal nutrition caused by TPN. METHODS: Rats were maintained with TPN with or without IGF-I (800 micrograms/day), and jejunal histology and epithelial ion transport were measured after 5 days. In a third TPN group without IGF-I, a short-term dose of IGF-I was added during in vitro flux chamber experiments. RESULTS: Rats given TPN with IGF-I had greater jejunal mucosal weight, greater protein and DNA content, and increased villus height and crypt depth compared with rats given TPN only. TPN increased ionic permeability and ion transport responses to secretory and absorptive agents. IGF-I in vivo reversed most of these changes; IGF-I in vitro enhanced sodium-dependent glucose absorption but had no other effects. CONCLUSIONS: Coinfusion of recombinant human IGF-I with TPN solution stimulates intestinal hyperplasia and attenuates transport changes induced by TPN. The latter effect seems to be primarily associated with the growth state of the epithelium. (Gastroenterology 1996 Dec;111(6):1501-8)     

Effect of parenteral nutrition on muscle amino acid output and 3-methylhistidine excretion in septic patients

The effects of adequate total parenteral nutrition (TPN) on nitrogen excretion, urea N percentage, 3-methylhistidine excretion, and leg amino acid output, were studied during the ten-day period following abdominal surgery for generalized peritonitis in nine patients. The first two postoperative days were without nutritional intake, TPN was started on the third postoperative day (57 cal/KgBW--40% as Intralipid--0.30 g of N/KgBW). Leg amino acid outputs were done before TPN (DO), then two days (D2) and eight days (D8) after TPN. Total nitrogen and urea N percentage did not significantly differ before and after TPN. Between DO and D2 there was a significant reduction of urinary 3-methylhistidine (467 +/- 37 to 280 +/- 29 mumol/24 h-P less than 0.001) and leg amino acid release (604 +/- 103 to 254 +/- 87 nmol/mn/100 g of calf muscle--P less than 0.01) reflecting reduction in muscle hypercatabolism despite the persistence of the septic state. Between D2 and D8, 3-methylhistidine remained stable while leg amino acid release continued to decrease (254 +/- 87 to 68 +/- 40 nmol/mn/100 g--P less than 0.05). This association suggests an increased muscle protein synthesis. A closer examination of the clinical evolution of these patients, especially concerning their septic evolution, shows that only improved patients with recovery from sepsis increased their muscle protein synthesis. Thus, in septic hypercatabolic patients TPN seems to be able to reduce muscle catabolism while the increase in protein synthesis is mainly the consequence of recovery from the septic state. In such patients TPN should be used as a preventive therapeutic measure.     

Enteral Nutrition as a Primary Therapy for Intestinal Lymphangiectasia: Value of Elemental Diet and Polymeric Diet Compared with Total Parenteral Nutrition

Intestinal lymphangiectasia (IL) is a rare disease requiring oral fat restriction. The aim of this study was to evaluate the efficacy of enteral nutrition compared to that of total parenteral nutrition (TPN). We retrospectively reviewed nine patients with IL presenting with protein-losing enteropathy. Of these, seven patients not responding to a low-fat diet were treated with elemental diet (ED), polymeric diet (PD) containing medium-chain triglycerides, or TPN. Improvement in serum total protein was observed in two of three on ED and in one of two on PD, compared with three of three on TPN. Enteric protein loss was improved in two of two on ED, one of two on PD, and two of two on TPN. Outpatients who continued to receive enteral nutrition maintained a total protein level. Enteral nutirition appears to be as effective as TPN for patients with IL, and it may provide a valid and safe alternative therapy.     

Total parenteral nutrition and the function of the intestinal microflora in Crohn's disease

The effect of total parenteral nutrition (TPN) on the following six intestinal microflora-associated characteristics (MACs) was studied in patients with Crohn's disease: faecal tryptic activity (FTA), formation of coprostanol, urobilinogen, and deoxycholic acid, and degradation of mucin and beta-aspartylglycine. The FTA showed high levels before TPN, in accordance with previous findings, and decreased during TPN. Formation of coprostanol, urobilinogen, and deoxycholic acid was reduced in some patients, whereas no changes were found in the mucin and beta-aspartylglycine degradation.     

COPD急性呼衰期肠内外营养支持的研究

目的:探讨慢性阻塞性肺疾病合并急性呼吸衰竭患者行机械通气支持治疗时给予早期肠内营养的优点。方法:32例机械通气患者随机分成早期肠内营养(EN)组和早期完全胃肠外营养(TPN)组，在摄入同等热量、同等氮量的条件下对营养及免疫指标、严重感染发生率、感染持续时间、机械通气时间、住院时间、临床营养及相关费用等指标进行比较，研究期为10天。结果：EN组及TPN组给予营养支持治疗后的营养及免疫指标均高于营养支持治疗前；营养支持治疗后EN组营养及免疫指标均高于TPN组；严重感染发生率、感染持续时间、机械通气时间、住院时间、临床营养及相关费用均低于TPN组。结论：慢性呼吸衰竭急性加重期患者行机械通气支持治疗时早期给予高脂低糖肠内营养疗法(EN)较早期完全胃肠外营养(TPN)能更好地提供营养，提高免疫力，减少并发症，缩短机械通气的时间，降低临床营养及相关费用，值得推广。     

阶段性营养支持在重症急性胰腺炎治疗中的应用

目的观察肠内和肠外联合阶段性营养对重症急性胰腺炎治疗效果的影响。方法重症急性胰腺炎患者50例分为完全胃肠外营养组（TPN组,n=25）和肠内营养加肠外阶段性营养组（PN＋EN组,n=25）,比较两组治疗效果及临床指标的变化。结果两组患者治疗后血淀粉酶均有下降,但两组间比较无显著性差异（P〉0．05）。营养支持后PN＋EN组在APACHE1I评分和CT评分较TPN组明显降低（P〈0．01）,两组血清白蛋白及血钙水平较治疗前升高（P〈0．01）,血糖明显降低（P〈0．01）,但两组间比较无显著性差异（P〉0．05）。与TPN组相比,PN＋EN组患者住院天数、腹胀缓解时间、体温恢复正常时间均明显缩短,感染发生率显著降低（P〈0．01）。结论肠内和肠外联合阶段性营养对重症急性胰腺炎治疗效果优于完全胃肠外营养。     

持续早期肠内营养联合肠黏膜保护对重症急性胰腺炎肠屏障功能影响的多中心随机对照临床试验

目的 观察持续早期肠内营养(EEN)联合肠黏膜保护对重症急性胰腺炎(SAP)患者肠屏障功能的影响.方法 选取2004年5月至2006年6月四个中心SAP患者79例,分为EEN联合肠黏膜保护组(联合组,39例)和完全肠外营养(TPN)组(40例).在发病后72 h内分别给予等氮源、等热量EEN和TPN.联合组给予肠内营养多聚合剂、精氨酸、谷氨酰胺和肠黏膜保护药物;TPN组采用中心静脉或外周静脉输注.入选后第1、7、14、21天行急性生理学及慢性健康状况(APACHE-Ⅱ)评分并检测血淀粉酶、二胺氧化酶(DAO)、内毒素、尿液肠脂肪酸结合蛋白浓度(IFABP-c)、肠脂肪酸结合蛋白含量(IFABP-t)、乳果糖与甘露醇(L/M)比值和肠道菌群变化,并观察并发症和住院时间、费用.结果 两组患者均无死亡.两组APACHE-Ⅱ评分随住院天数增加均呈递减趋势,联合组第7天APACHE-Ⅱ评分为6.00±1.60,低于TPN组(7.08±2.34,P＜0.05).第7,14,21天联合组血内毒素分别为(39.30±15.82)、(22.64±14.31)、(14.81±10.93)Eu/L,L/M比值分别为0.28±0.25、0.21±0.18和0.08±0.04,IFABP-c分别为(15.62±5.26)、(5.46±1.18)和(3.26±0.94)pg/ml,均明显低于TPN组(P值均＜0.05).联合组肠道菌群结构无明显变化,而TPN组出现肠道菌群结构变化.TPN组感染率(包括胰腺感染、腹腔感染和泌尿道、呼吸道感染)高于联合组(26.47%比3.44%,P＜0.01).联合组住院费用为(25 900±14 200)元,平均住院天数为(20.0±5.7)d,均低于TPN组[(46 800±4030)元和(34.5±19.9)d,P值均＜0.05)].结论 EEN联合肠黏膜保护可降低SAP患者肠道通透性,改善肠道灌注,保持肠道菌群,减少内毒素易位,对肠屏障功能有保护作用,且缩短病程、节约住院费用.