Intestinal barrier dysfunction in liver cirrhosis assessed by iohexol test.

OBJECTIVE: To study gut barrier function in patients with liver cirrhosis (LC) by evaluating the intestinal permeability (IP) and its relationship with the severity and etiology of the disease. PATIENTS AND METHODS: The study included 31 patients with LC and 25 healthy controls. Child-Pugh score was used for evaluation of the LC severity. IP was assessed by the rise in levels of iohexol, which was administered orally (25 mL, 350 mg/mL) 2 h after breakfast. Three and six hours later serum (SIC mg/L) and urine (UIC g/mol) iohexol concentrations were determined by a validated HPLC-UV technique. RESULTS: Patients with LC had significantly higher mean SIC value compared with control group at 3 h (2.05 ± 1.67 vs. 1.25 ± 1.41 mg/L, p=0.021, as well as at 6 h (2.20 ± 2.65 vs. 1.11 ± 1.06 mg/L, p=0.001) after ingestion. No significant difference was found in mean SIC value of patients at 3 and 6 h. 23% of the patients had an increased IP. The mean iohexol urine recovery of patients was similar to that of the controls both at 3 h and at 6 h. Mean SIC values were significantly higher in patients with advanced Child C class than in healthy controls or the subgroup with Child B class, both at 3 h (2.54 ± 1.95 mg/L vs. 1.11 ± 1.06 mg/L, p=0.007) or (2.57 ± 1.85 mg/L vs. 1.35±1.32 mg/L, p=0.005) and at 6 h (2.57 ± 1.85 mg/L vs. 1.25 ± 1.40 mg/L, p=0.002) or 2.54 ± 1.95 mg/L vs. 1.07 ± 0.35 mg/L, p=0.02). Cirrhotic patients with ascites had significantly higher SIC in comparison with the controls, both at 3 h (2.31 ± 1.74 vs. 1.25 ± 1.41 mg/, p=0.009) and at 6 h (2.20 ± 1.87 vs. 1.11 ± 1.06 mg/l, p=0.007). In the subgroup of patients with alcoholic LC, the mean SIC values at 3 and 6 h (2.29 ± 1.80, 2.33 ± 1.85 mg/L, respectively) were significantly higher (p= 0.016, p=0.003) compared to the control group (1.25 ± 1.41, 1.11 ± 1.06 mg/L, respectively). CONCLUSIONS: Increased IP is found in 23% of cirrhotic patients. Permeability alterations are significantly more pronounced in patients with advanced LC with the presence of ascites and in those with alcoholic etiology.

Measurement of intestinal permeability using lactulose and mannitol with conventional five hours and shortened two hours urine collection by two different methods: HPAE-PAD and LC-MSMS.

Urinary excretion of two orally-administered non-metabolizable sugars, lactulose and mannitol, is a valuable marker for evaluating intestinal permeability. Usually this test involves a time consuming procedure of about 5 hour's urine collection, which makes the test incompatible to some extent. As the results are expressed as the ratio of lactulose and mannitol recovered in urine within certain time, it may be possible to get similar result despite the reduced urine collection time of 2 hours. Moreover, different laboratories do the test by different methods, which make the results incomparable between laboratories. Here, we are also trying to find the correlation between results from most commonly used methods: HPAE-PAD and LC-MSMS. The lactulose: mannitol (LM) test was performed in a cohort of Bangladeshi infants considered at-risk for environmental enteropathy. 208 urine specimens from 104 (52 male and 52 female) infants were collected at 2 and 5 hours after LM solution administration and were tested for lactulose and mannitol by two different methods, one HPAE-PAD platform and another LC-MSMS platform. Median age of the children was 15.0 months (range 6.9 to 25.8 months) and their mean weight-for-age z-score was -0.92. A higher percentage of lactulose and mannitol recovery was found in 5 hours urine collection than in the corresponding 2 hours by both HPAE-PAD and LC-MSMS method, but when results were expressed as lactulose to mannitol ratio (LMR) there was no significant difference between 2 and 5 hours urine collection in both HPAE-PAD (P = 0.138) and LC-MSMS (P = 0.099) method. LMR based on 2 hours urine collection correlated well with LMR based on traditional 5 hours urine collection (Spearman's correlation coefficient 0.578 and 0.604 respectively for HPAE-PAD and LC-MSMS). In future, LM test to assess intestinal permeability in children can be simplified by shortening the urine collection time from 5 hours to 2 hours.

Measurement of prostaglandin metabolites is useful in diagnosis of small bowel ulcerations.

BACKGROUND: We recently reported on a hereditary enteropathy associated with a gene encoding a prostaglandin transporter and referred to as chronic enteropathy associated with SLCO2A1 gene (CEAS). Crohn's disease (CD) is a major differential diagnosis of CEAS, because these diseases share some clinical features. Therefore, there is a need to develop a convenient screening test to distinguish CEAS from CD. AIM: To examine whether prostaglandin E major urinary metabolites (PGE-MUM) can serve as a biomarker to distinguish CEAS from CD. METHODS: This was a transactional study of 20 patients with CEAS and 98 patients with CD. CEAS was diagnosed by the confirmation of homozygous or compound heterozygous mutation of SLCO2A1. We measured the concentration of PGE-MUM in spot urine by radioimmunoassay, and the concentration was compared between the two groups of patients. We also determined the optimal cut-off value of PGE-MUM to distinguish CEAS from CD by receiver operating characteristic (ROC) curve analysis. RESULTS: Twenty Japanese patients with CEAS and 98 patients with CD were enrolled. PGE-MUM concentration in patients with CEAS was significantly higher than that in patients with CD (median 102.7 vs 27.9 µg/g × Cre, P < 0.0001). One log unit increase in PGE-MUM contributed to 7.3 increase in the likelihood for the diagnosis of CEAS [95% confidence interval (CI) 3.2-16.7]. A logistic regression analysis revealed that the association was significant even after adjusting confounding factors (adjusted odds ratio 29.6, 95%CI 4.7-185.7). ROC curve analysis revealed the optimal PGE-MUM cut-off value for the distinction of CEAS from CD to be 48.9 µg/g × Cre with 95.0% sensitivity and 79.6% specificity. CONCLUSION: PGE-MUM measurement is a convenient, non-invasive and useful test for the distinction of CEAS from CD.

Arteriolar Hyalinosis Predicts Increase in Albuminuria and GFR Decline in Normo- and Microalbuminuric Japanese Patients With Type 2 Diabetes.

OBJECTIVE: This study investigated the association between renal histology, as assessed by morphometric analysis using light (LM) and electron (EM) microscopy, and changes in urinary albumin excretion (UAE) and glomerular filtration rate (GFR) in Japanese people with type 2 diabetes in the early stages of diabetic nephropathy. RESEARCH DESIGN AND METHODS: We performed percutaneous renal biopsies in 29 patients with type 2 diabetes (22 men, mean ± SD age 49 ± 10 years and GFR 119 ± 27 mL/min/1.73 m2, with 15 normoalbuminuric [UAE <20 µg/min] and 14 microalbuminuric [UAE 20-200 µg/min]) to clarify which histological factors were associated with changes in UAE and GFR during 8.0 ± 3.5 years' follow-up. Glomerular structural changes including mesangial volume fraction [Vv(Mes/glom)] were estimated using EM, whereas the index of arteriolar hyalinosis (IAH) score was assessed by LM. Patients underwent annual measurement of GFR using iohexol injection with simultaneous urine collections for UAE. RESULTS: Vv(Mes/glom) was negatively correlated with baseline and follow-up GFR but not with UAE. The IAH score was positively correlated with UAE and negatively correlated with GFR at follow-up, but it was not correlated with either UAE or GFR at baseline. GFR at follow-up was significantly decreased from baseline in patients with IAH scores ≥2.0 and significantly lower than in patients with IAH scores <2.0. Patients with IAH scores <2.0 showed no significant change in GFR during follow-up. CONCLUSIONS: Arteriolar hyalinosis is an additional histological predictor for albuminuria increase and GFR decline in normo- and microalbuminuric Japanese people with type 2 diabetes.

Markers of Intestinal Damage and their Relation to Cytokine Levels in Cardiac Surgery Patients.

OBJECTIVES: In patients undergoing cardiac surgery, both extracorporeal circulation (ECC) and intraoperative mesenterial hypoperfusion may account for increased cytokine levels and lead to postoperative gastrointestinal (GI) symptoms. METHODS: We investigated levels of the intestinal damage markers intestinal fatty acid binding protein (I-FABP in plasma [n = 72] and urine [n = 37]), citrulline (in plasma [n = 35]), and claudin-3 (in urine [n = 37]) in patients undergoing aortic or mitral valve surgery with or without coronary artery bypass grafting. Furthermore, the relationship between these markers and the surgery-induced cytokine response was explored by measuring serial plasma levels of tumor necrosis factor-α, interleukin (IL)-6, IL-8, and IL-10 (n = 35). Finally, the relationship between markers of intestinal damage and GI-symptoms (abdominal pain, ileus, vomiting, diarrhea, time to first defecation) was assessed. RESULTS: Plasma and urinary I-FABP levels, and urinary claudin-3 levels peaked at the end of surgery, while citrulline levels were not influenced by surgery. ECC duration correlated with plasma I-FABP levels (r = 0.31, P = 0.007). Plasma levels of all measured cytokines increased during surgery, with peak levels observed either at the end of surgery or on the first postoperative day. While ECC duration correlated with IL-6 and IL-8 release (r = 0.43, P = 0.01 and r = 0.36, P = 0.04 respectively), there was no direct relationship between I-FABP and claudin-3 levels and cytokine concentrations. No patients developed significant GI or non-GI complications, and I-FABP and claudin-3 release appeared not to be related to postoperative GI symptoms, although the incidence of these symptoms may have limited a reliable assessment. CONCLUSIONS: Longer duration of ECC is associated with a more pronounced release of intestinal injury markers and inflammatory cytokines, but intestinal injury markers are not directly related to the observed increase in cytokine levels or GI-symptoms. These findings indicate that ECC duration contributes to the cytokine response observed in cardiac surgery patients and that intestinal injury itself is not a causative factor for this response.

Can urinary indolylacroylglycine levels be used to determine whether children with autism will benefit from dietary intervention?

BACKGROUND: An increase in urinary indolyl-3-acryloylglycine (IAG) has been reported in children with autism spectrum disorders (ASD) who suffer with bowel problems in comparison to ASD children without gastrointestinal (GI) problems. The case for dietary intervention for ASD children with GI symptoms might be strengthened were such a difference to be autism-specific. METHODS: Quantitative analysis of urinary IAG levels was performed for 53 children on the autism spectrum and 146 age-matched controls. The parents of each child were asked to provide information on bowel symptoms experienced by the child and their eating habits over a period of 2 wk. RESULTS: We find no significant difference in urinary IAG levels between the ASD children with GI problems and ASD children without GI problems. Although we see some difference between ASD children with GI problems and controls in mainstream schools with GI problems, the difference between non-autistic children with other developmental disorders and controls in mainstream schools is more significant so that any difference is not autism-specific. We find a strong correlation between bowel symptoms and diet problems in ASD children, especially idiosyncratic feeding behavior and we show that ASD children suffering from multiple bowel symptoms tend to be those who also have dietary problems. CONCLUSION: We found no evidence to support the hypothesis that children with ASD who suffer with bowel problems have increased levels of urinary IAG in comparison to children with ASD who do not have gastrointestinal problems.

Modern approach for determination of lactulose, mannitol and sucrose in human urine using HPLC-MS/MS for the studies of intestinal and upper digestive tract permeability.

A new analytical procedure was described for the simultaneous determination of lactulose, mannitol and sucrose in urine, in which HILIC chromatography and tandem mass spectrometry detection are used. Sugars are orally administered for the estimation of intestinal permeability in children digestive tract. Samples were purified by dispersive solid phase extraction (d-SPE) using Amberlite MB150 resin. Raffinose was selected as an internal standard. The chosen chromatographic separation was carried out on ZIC(®)-HILIC column in 10 min at a flow rate of 0.3 mL/min, using mixture of acetonitrile (ACN) and ammonium acetate (NH(4)Ac) in water (H(2)O) as the mobile phase. Within-run precision (CV) measured at three concentrations was 1.08%, 0.32% and 0.49% for lactulose; 1.88%, 0.47% and 0.75% for mannitol, 2.95%, 1.31% and 0.6% for sucrose. Between-run CVs were 0.75%, 1.1% and 1.2% for lactulose; 1.1%, 1.02% and 1.01% for mannitol; 1.17%, 1.4% and 1.05% for sucrose. Analytical recovery of all three sugar probes was 95.06-99.92%. The detection limits were: 15.94 ng/mL for lactulose, 17.10 ng/mL for sucrose and 11.48 ng/mL for mannitol. The proposed method is rapid, simple, sensitive and suitable for the determination of intestinal permeability of the sugar derivatives in children.

Abnormal gut integrity is associated with reduced linear growth in rural Malawian children.

The aim of the present study was to investigate the relation of environmental enteropathy, as measured by the dual sugar absorption test, to linear growth faltering in 2- to 5-year-old Malawian children. Dietary quality, food insecurity, anthropometry, and site-specific sugar testing were measured in 418 children, and anthropometry was reassessed 3 months later. A linear regression model predicting linear growth was created. Better growth was associated with less urinary lactulose excretion, more clean water usage, not sleeping with animals, and no previous history of malnutrition. Eighty-seven percent of children studied demonstrated evidence of environmental enteropathy. In conclusion, abnormal gut integrity is associated with reduced linear growth in a population of rural African preschool-age children.

New Insight in Loss of Gut Barrier during Major Non-Abdominal Surgery.

BACKGROUND: Gut barrier loss has been implicated as a critical event in the occurrence of postoperative complications. We aimed to study the development of gut barrier loss in patients undergoing major non-abdominal surgery. METHODOLOGY/PRINCIPAL FINDINGS: Twenty consecutive children undergoing spinal fusion surgery were included. This kind of surgery is characterized by long operation time, significant blood loss, prolonged systemic hypotension, without directly leading to compromise of the intestines by intestinal manipulation or use of extracorporeal circulation. Blood was collected preoperatively, every two hours during surgery and 2, 4, 15 and 24 hours postoperatively. Gut mucosal barrier was assessed by plasma markers for enterocyte damage (I-FABP, I-BABP) and urinary presence of tight junction protein claudin-3. Intestinal mucosal perfusion was measured by gastric tonometry (P(r)CO2, P(r-a)CO2-gap). Plasma concentration of I-FABP, I-BABP and urinary expression of claudin-3 increased rapidly and significantly after the onset of surgery in most children. Postoperatively, all markers decreased promptly towards baseline values together with normalisation of MAP. Plasma levels of I-FABP, I-BABP were significantly negatively correlated with MAP at (1/2) hour before blood sampling (-0.726 (p<0.001), -0.483 (P<0.001), respectively). Furthermore, circulating I-FABP correlated with gastric mucosal P(r)CO2, P(r-a)CO2-gap measured at the same time points (0.553 (p = 0.040), 0.585 (p = 0.028), respectively). CONCLUSIONS/SIGNIFICANCE: This study shows the development of gut barrier loss in children undergoing major non-abdominal surgery, which is related to preceding hypotension and mesenterial hypoperfusion. These data shed new light on the potential role of peroperative circulatory perturbation and intestinal barrier loss.

Attenuated renal and intestinal injury after use of a mini-cardiopulmonary bypass system.

BACKGROUND: Transient, subclinical myocardial, renal, intestinal, and hepatic tissue injury and impaired homeostasis is detectable even in low-risk patients undergoing conventional cardiopulmonary bypass (CPB). Small extracorporeal closed circuits with low priming volumes and optimized perfusion have been developed to reduce deleterious effects of CPB. METHODS: A prospective, randomized trial was conducted in 49 patients undergoing elective coronary artery bypass graft surgery either with the use of a standard or mini-CPB system (Synergy). We determined early postoperative inflammatory response (leukocytosis, C-reactive protein, urine interleukin-6), platelet consumption and activation (urine thromboxane B2), proximal renal tubular injury (urine N-acetyl-glucosaminidase), and intestinal injury (intestinal fatty acid binding protein). RESULTS: In patients undergoing coronary artery bypass grafting with a mini-CPB system, we observed decreased priming volumes with subsequent attenuation of on-pump hemodilution, improved hemostatic status with reduced platelet consumption and platelet activation, decreased postoperative bleeding and minimized transfusion requirements. We also found reduced leukocytosis and decreased urinary interleukin-6. Levels of urine N-acetyl-glucosaminidase were on average threefold lower, and urinary intestinal fatty acid binding protein was 40% decreased in the patients on the mini-CPB system, as compared with standard CPB. CONCLUSIONS: The use of the mini-CPB system during myocardial revascularization represents a viable nonpharmacologic strategy that can attenuate the alterations in the hemostatic system, reduce bleeding and transfusion requirements, decrease systemic inflammatory response, and reduce immediate postoperative renal and intestinal tissue injury.

A sensitive enzymatic assay for the determination of sucrose in serum and urine.

BACKGROUND: Sucrose permeability has been suggested as a simple and non-invasive marker of gastric mucosal damage. We here report on a sensitive enzymatic assay using four sequential enzyme reactions coupled with reduced thio-NADPH. METHODS: Sucrose is phosphorylated by sucrose phosphorylase (EC2.4.1.7). The subsequent reaction in the presence of phosphoglucomutase (EC5.4.2.2) and glucose-1,6-diphosphate forms glucose-6-phosphate. Sucrose of the monad forms the dyad thio-NADPH. The reaction is monitored by changes in absorbance at 405 nm. RESULTS: The lower limit of detection (3SD method) was 2.8 micromol/l for serum and 7.0 micromol/l for urine. The precision of the method was <4.0%, and has sufficient analytical range. CONCLUSIONS: The assay was sensitive enough to monitor serum sucrose concentrations during the sucrose permeability test and an automated assay may be useful in a large number of subjects.

Aluminum contamination of parenteral nutrition and aluminum loading in children on long-term parenteral nutrition.

BACKGROUND: Children who are receiving parenteral nutrition are at risk of aluminum overload, which may contribute to such side effects as osteopenic bone disease. The aim of the present study is to determine the aluminum contamination of parenteral nutrition solutions and their components, and to assess the aluminum status of children on long-term parenteral nutrition. METHODS: Aluminum concentrations were determined by graphite furnace absorption spectroscopy in components and in final parenteral nutrition solutions. The urinary aluminum excretion and plasma aluminum concentration were determined in 10 children on long-term parenteral nutrition. RESULTS: The mean aluminum concentration in the administered parenteral nutrition solutions was 1.6 +/- 0.9 micromol x l(-1)(mean +/- standard deviation (SD)). The resulting mean aluminum daily intake of the 10 patients was 0.08 +/- 0.03 micromol x kg(-1) x day(-1). CONCLUSIONS: Compared to two previous studies performed in 1990 and in 1995 in our hospital, the aluminum contamination of parenteral nutrition solutions and the daily aluminum intake of the children seemed to decrease. However, the plasma aluminum concentration and daily urinary aluminum excretion of the children still remain above normal standards. The children had no clinical symptoms of bone disease but aluminum accumulation in tissue can not be excluded. To prevent this iatrogenic toxicity, the aluminum contamination of parenteral nutrition should be assessed regularly.

Urinary excretion of orally ingested gastrografin on CT.

Renal excretion of orally ingested gastrografin has rarely been reported on computed tomography (CT). We studied the unenhanced scans of 82 patients with bowel disorders or perforation to assess the prevalence of urinary contrast material (CM) in various bowel diseases. We also assessed the clinical significance of this sign. In addition, we reviewed the unenhanced CT scans of 100 randomly selected patients without bowel diseases as a control group. Twenty-nine of the 58 patients with bowel diseases, six of nine with free perforation, and one of 15 with covered perforation had CM in the urinary tract. None of the 100 without bowel disease showed urinary CM. Statistical analysis was done by using the Fisher's exact test. The prevalence of urinary CM was highest in inflammatory bowel disease, radiation enteritis, and free perforation (p < 0. 0001). This study shows that the CT finding of orally ingested gastrografin in the urinary tract differentiates patients with bowel disease from those without.

The ursodeoxycholic acid-p-aminobenzoic acid deconjugation test, a new tool for the diagnosis of bacterial overgrowth syndrome.

OBJECTIVE: To determine the possible complementary role of the ursodeoxycholic acid-p-aminobenzoic acid (UDCA-PABA) loading test in the diagnosis of intestinal bacterial overgrowth. DESIGN: A prospective clinical study. PATIENTS AND METHODS: The hydrogen breath and UDCA-PABA tests were performed simultaneously in 68 patients with suspected contaminated small bowel syndrome (CSBS), and in 10 healthy control subjects. The hydrogen breath test was performed by oral loading of 25 g of lactose and/or 10 g of lactulose. The UDCA-PABA test was carried out by oral loading of 250 mg of UDCA-PABA conjugate, followed by measurement of the amount of PABA excreted in the urine. The diagnosis of bacterial overgrowth was considered to be established when either the hydrogen breath test or the UDCA-PABA test produced abnormal results. RESULTS: Thirty-five of the 68 patients proved to have CSBS. In 13 of these 35 patients, only the enhanced urinary PABA excretion (11.7 +/- 1.42 mg vs. 3.6 +/- 0.68 mg) indicated bacterial overgrowth, 15 of the 35 patients gave only a positive hydrogen breath test, and in the remaining seven cases the results of both tests were abnormal. In eight CSBS patients, the urinary excretion of PABA was decreased significantly following 10-day tinidazole treatment (5.5 +/- 1.29 mg vs. 13.1 +/- 2.07 mg). CONCLUSION: The UDCA-PABA test is a valuable clinical method for the detection of bacterial overgrowth, especially in cases where hydrogen production alone fails to reveal CSBS. It is also a useful procedure for evaluating the efficacy of antibacterial treatment.

The importance of urinary magnesium values in patients with gut failure.

OBJECTIVE: To determine whether urinary magnesium (Mg) values in patients with gut failure would be more helpful than serum Mg measurements in assessment of Mg deficiency. DESIGN: We compared serum and urinary Mg values in 16 patients with gut failure and 16 age- and sex-matched control subjects. MATERIAL AND METHODS: Sixteen patients with gut failure (nine women and seven men; mean age, 59 years) had serum and 24-hour urinary mg measured before Mg replacement therapy. Short bowel syndrome was present in 75%, and diffuse small bowel disease was present in 25%. RESULTS: The median value for serum Mg was 1.7 mg/dL for patients and 2.0 mg/dL for healthy control subjects (P < 0.001). The median values for urinary Mg were 19 mg and 127 mg per 24-hour specimen in patient and control groups, respectively (P < 0.001). A strong correlation was noted between serum Mg and urinary Mg levels. All patients had low urinary Mg values even though 9 of 16 (56%) had normal serum Mg values. Two patients with normal serum Mg concentrations had urinary Mg values of 20 mg/24 h (25% of normal). Serum, but not urinary, Mg correlated significantly with the length of remaining small bowel (P = 0.03). CONCLUSIONS: Urinary Mg declines before serum Mg and is an earlier and more reliable indicator of evolving Mg deficiency. On the basis of these observations and those showing beneficial effects of parenterally administered Mg supplements on urinary citrate excretion (and, presumably, formation of calcium oxalate stones), replacement of Mg in patients with gut failure should be targeted at normalizing urinary Mg.

Bowel syndrome.

AIDS: A new outpatient trial is studying glutamine as a treatment for leaky bowel syndrome associated with HIV infection. Participants will be given urine tests and a 15 to 20 minute biopsy which is done by swallowing a small capsule (after numbing the throat) to see if it goes into the intestine; the capsule is then pulled out. After biopsy, the groups are divided into glutamine treatment groups with one placebo group. After 28 days, permeability tests and biopsies are redone.^ieng

Treatment of enteric hyperoxaluria with calcium-containing organic marine hydrocolloid.

An organic marine hydrocolloid (OMH) charged with calcium ('Ox-Absorb') was studied in vitro for oxalate binding and in patients with enteric hyperoxaluria to investigate oxalate excretion and the inhibitory activity on crystal formation of the urine. In-vitro experiments showed complete binding of oxalate to OMH. In clinical studies in nineteen patients with intestinal disorders and stone formation, urinary oxalate excretion was significantly lower during OMH treatment than off treatment. The activity product index of calcium oxalate was reduced on treatment. A pronounced rise in the inhibitory activity of urine was seen in two patients with very low pretreatment values. Most patients experienced virtual normalisation of bowel function, and in those with severe stone formation there was substantial clinical improvement. It is concluded that OMH has the capacity to bind oxalate in vitro and to reduce urinary oxalate excretion. These observations suggest a new promising treatment for enteric hyperoxaluria.