Plasma phospholipids and fatty acid composition differ between liver biopsy-proven nonalcoholic fatty liver disease and healthy subjects.

BACKGROUND: There is growing evidence that nonalcoholic fatty liver disease (NAFLD) is associated with perturbations in liver lipid metabolism. Liver phospholipid and fatty acid composition have been shown to be altered in NAFLD. However, detailed profiles of circulating lipids in the pathogenesis of NAFLD are lacking. OBJECTIVE: Therefore, the objective of the present study was to examine circulating lipids and potential mechanisms related to hepatic gene expression between liver biopsy-proven simple steatosis (SS), nonalcoholic steatohepatitis (NASH) and healthy subjects. SUBJECTS: Plasma phospholipid and fatty acid composition were determined in 31 healthy living liver donors as healthy controls (HC), 26 patients with simple hepatic steatosis (SS) and 20 with progressive NASH. Hepatic gene expression was analyzed by Illumina microarray in a subset of 22 HC, 16 SS and 14 NASH. RESULTS: Concentrations of phosphatidylethanolamine (PE) increased relative to disease progression, HC

Inverse relationship between body mass index and mortality in older nursing home residents: a meta-analysis of 19,538 elderly subjects.

Body mass index (BMI) and mortality in old adults from the general population have been related in a U-shaped or J-shaped curve. However, limited information is available for elderly nursing home populations, particularly about specific cause of death. A systematic PubMed/EMBASE/CINAHL/SCOPUS search until 31 May 2014 without language restrictions was conducted. As no published study reported mortality in standard BMI groups (<18.5, 18.5-24.9, 25-29.9, ≥30 kg/m(2)), the most adjusted hazard ratios (HRs) according to a pre-defined list of covariates were obtained from authors and pooled by random-effect model across each BMI category. Out of 342 hits, 20 studies including 19,538 older nursing home residents with 5,223 deaths during a median of 2 years of follow-up were meta-analysed. Compared with normal weight, all-cause mortality HRs were 1.41 (95% CI = 1.26-1.58) for underweight, 0.85 (95% CI = 0.73-0.99) for overweight and 0.74 (95% CI = 0.57-0.96) for obesity. Underweight was a risk factor for higher mortality caused by infections (HR = 1.65 [95% CI = 1.13-2.40]). RR results corroborated primary HR results, with additionally lower infection-related mortality in overweight and obese than in normal-weight individuals. Like in the general population, underweight is a risk factor for mortality in old nursing home residents. However, uniquely, not only overweight but also obesity is protective, which has relevant nutritional goal implications in this population/setting.

Validity and reliability of the new Canadian Nutrition Screening Tool in the 'real-world' hospital setting.

BACKGROUND/OBJECTIVES: Nutrition screening should be initiated on hospital admission by non-dietitians. This research aimed to validate and assess the reliability of the Canadian Nutrition Screening Tool (CNST) in the 'real-world' hospital setting. SUBJECTS/METHODS: Adult patients were admitted to surgical and medical wards only (no palliative patients). Study 1--Nutrition Care in Canadian Hospitals (n=1014): development of the CNST (3 items: weight loss, decrease food intake, body mass index (BMI)) and exploratory assessment of its criterion and predictive validity. Study 2--Inter-rater reliability and criterion validity assessment of the tool completed by untrained nursing personnel or diet technician (DT) (n=150). Subjective Global Assessment performed by site coordinators was used as a gold standard for comparison. RESULTS: Study 1: The CNST completed by site coordinators showed good sensitivity (91.7%) and specificity (74.8%). Study 2: In the subsample of untrained personnel (160 nurses; one DT), tool's reliability was excellent (Kappa=0.88), sensitivity was good (>90%) but specificity was low (47.8%). However, using a two-item ('yes' on both weight change and food intake) version of the tool improved the specificity (85.9%). BMI was thus removed to promote feasibility. The final two-item tool (study 1 sample) has a good predictive validity: length of stay (P<0.001), 30-day readmission (P=0.02; X(2) 5.92) and mortality (P<0.001). CONCLUSIONS: The simple and reliable CNST shows good sensitivity and specificity and significantly predicts adverse outcomes. Completion by several untrained nursing personnel confirms its utility in the nursing admission assessment.

Prescription of trace elements in adults on home parenteral nutrition: current practice based on the Canadian Home Parenteral Nutrition Registry.

BACKGROUND: Since the introduction of long-term parenteral nutrition (PN), morbidity due to inadequate replacement or toxicity of routinely administered trace elements has been well described. After decades of experience, much debate still exists about optimal supplementation. In practice, trace elements (TEs) seem to be frequently provided by prescribing an all-inclusive commercial multi-TE admixture with little dosage flexibility. AIM: Our goal was to review TE supplementation practice among 5 PN support centers across Canada, through a retrospective review of the Canadian Home PN Registry. METHODS: Baseline demographic, clinical, and biochemical parameters along with information regarding the PN prescription of 135 patients with complete records were retrieved from the registry database collected between 2005 and 2007. TE supplementation prescriptions were compared with recent guidelines as well as between groups of patients with different PN indications and dietary intake status. Consent was signed by all participating patients. RESULTS: The average daily PN concentrations of TE were as follows: zinc, 8.6 ± 5.5 mg (130.92 ± 84.23 µmol); manganese, 452 ± 184 µg (8.22 ± 3.34 µmol); selenium, 78 ± 45 µg (0.99 ± 0.57 µmol); chromium, 11 ± 5 µg (0.21 ± 0.10 µmol); copper, 0.64 ± 0.35 mg (10.11 ± 5.58 µmol); and iodine, 77 ± 42 µg (0.61 ± 0.33 µmol). The mean daily supplementation of zinc, manganese, copper, and selenium exceeded published recommendations. Patients' underlying anatomy or indication for PN did not significantly influence decisions regarding replacement standards. CONCLUSION: Parenteral TE supplementation in Canadian PN programs needs to be reviewed and adjusted according to most current guidelines. This may require a reevaluation of the commercial TE preparations currently available in Canada and potential new products worldwide to avoid oversupplementation and potential toxicity.

Effects of manganese from a commercial multi-trace element supplement in a population sample of Canadian patients on long-term parenteral nutrition.

BACKGROUND: Long-term parenteral nutrition (PN) can be associated with micronutrient deficiency or toxicity depending on supplementation. Recently, hypermanganesemia and potential neurological toxicity were reported. The aim of this study was to assess the effect of manganese supplementation in a sample of patients on long-term PN receiving manganese (Mn) as part of a multi-trace element (TE) supplement. METHODS: A convenience sample of 16 patients underwent clinical and blood biochemical measurements as well as magnetic resonance imaging (MRI) of the brain. Descriptive statistics were performed. RESULTS: The mean daily Mn supplementation was 7.28 ± 0.97 µmol/d (400 ± 53 µg/d), which was within the American Medical Association Nutrition Advisory Group guidelines of 2.73-14.56 µmol/d (150-800 µg/d) but exceeded the American Society for Parenteral and Enteral Nutrition (A.S.P.E.N.) 2002 recommendations of 1.09-1.82 µmol/d (60-100 µg/d). The mean whole blood Mn level was 1.38 ± 0.29 times the upper limit of normal (ULN), and 8 of 14 patients with blood measurements had Mn levels above ULN. On MRI, 81% of patients had high signals on T1-weighted images assumed to be Mn deposits in their basal ganglia. Two patients with positive MRI (15%) had a clinical diagnosis of Parkinson disease. Multiple neuropsychiatric complaints were reported, including depression (66%), lack of concentration (42%), memory disturbances (17%), and gait instability (8%). CONCLUSION: These results suggest that Mn status is elevated in these patients. Manganese supplementation should be used with caution in patients receiving long-term PN, and attention should be paid to the Mn content of multi-TE supplements.

Canadian home parenteral nutrition (HPN) registry: validation and patient outcomes.

BACKGROUND: In Canada, there are an estimated 400 home parenteral nutrition (HPN) patients. In 2006, a registry was created to gather patient outcome information. The aim of this study was to validate the registry and report on HPN patient outcomes. METHODS: Several demographic, clinical parameters were collected. For the validation, paired t test and intraclass correlation coefficient (ICC) were used to assess agreement between repeat entries. For the outcome report, paired t test was used to assess changes, and survival analysis was performed using the Kaplan-Meier method. Results are expressed as mean ± SEM. RESULTS: On validation, there was high correlation/agreement (P < .05) for most parameters except vascular access/line sepsis, liver disease (ultrasound, biopsy, diagnoses), and hospitalizations. For the outcome report, 96 patients had their data entered at 2.24 ± 0.11 years after baseline. Over the period, there was a significant reduction in PN calories (P = .001) and proteins (P < .001). There were no significant changes in nutrition parameters and laboratory results except for lower platelet counts (P = .028), lower plasma potassium (P = .030), and a trend toward an increase in bilirubin from 19.29 ± 4.65 to 29.06 ± 8.73 µmol/L (P = .071). The QOL decreased significantly over time (P < .001) and the survival on HPN was 17.67 ± 1.89 years. CONCLUSIONS: The registry is a valid tool to assess several clinical parameters. On follow-up, HPN patients maintain good nutrition status while PN is reduced but do have a reduced quality of life.

Randomised placebo-controlled trial of teduglutide in reducing parenteral nutrition and/or intravenous fluid requirements in patients with short bowel syndrome.

BACKGROUND AND AIMS: Teduglutide, a GLP-2 analogue, may restore intestinal structural and functional integrity by promoting repair and growth of the mucosa and reducing gastric emptying and secretion, thereby increasing fluid and nutrient absorption in patients with short bowel syndrome (SBS). This 24-week placebo-controlled study evaluated the ability of teduglutide to reduce parenteral support in patients with SBS with intestinal failure. METHODS: In 83 patients randomised to receive subcutaneous teduglutide 0.10 mg/kg/day (n = 32), 0.05 mg/kg/day (n = 35) or placebo (n = 16) once daily, parenteral fluids were reduced at 4-week intervals if intestinal fluid absorption (48 h urine volumes) increased ≥ 10%. Responders were subjects who demonstrated reductions of ≥ 20% in parenteral volumes from baseline at weeks 20 and 24. The primary efficacy end point, a graded response score (GRS), took into account higher levels and earlier onset of response, leading to longer duration of response. The intensity of the response was defined as a reduction from baseline in parenteral volume (from 20% to 100%), and the duration of the response was considered the response at weeks 16, 20 and 24. The results were tested according to a step-down procedure starting with the 0.10 mg/kg/day dose. RESULTS: Using the GRS criteria, teduglutide in a dose of 0.10 mg/kg/day did not have a statistically significant effect compared with placebo (8/32 vs 1/16, p=0.16), while teduglutide in a dose of 0.05 mg/kg/day had a significant effect (16/35, p = 0.007). Since parenteral volume reductions were equal (353 ± 475 and 354 ± 334 ml/day), the trend towards higher baseline parenteral volume (1816 ± 1008 vs 1374 ± 639 ml/day, p=0.11) in the 0.10 mg/kg/day group compared with the 0.05 mg/kg/day group may have accounted for this discrepancy. Three teduglutide-treated patients were completely weaned off parenteral support. Serious adverse events were distributed similarly between active treatment groups and placebo. Villus height, plasma citrulline concentration and lean body mass were significantly increased with teduglutide compared with placebo. CONCLUSIONS: Teduglutide was safe, well tolerated, intestinotrophic and suggested pro-absorptive effects facilitating reductions in parenteral support in patients with SBS with intestinal failure. ClinicalTrials.gov number NCT00172185.

Teaching in small portions dispersed over time enhances long-term knowledge retention.

BACKGROUND: A primary goal of education is to promote long-term knowledge storage and retrieval. OBJECTIVE: A prospective interventional study design was used to investigate our research question: Does a dispersed curriculum promote better short- and long-term retention over a massed course? METHODS: Participants included 20 gastroenterology residents from the University of Calgary (N = 10) and University of Toronto (N = 10). Participants completed a baseline test of nutrition knowledge. The nutrition course was imparted to University of Calgary residents for 4 h occurring 1 h weekly over 4 consecutive weeks: dispersed delivery (DD). At the University of Toronto the course was taught in one 4h academic half-day: massed delivery (MD). Post-curriculum tests were administered at 1 week and 3 months to assess knowledge retention. RESULTS: The baseline scores were 46.39 +/- 6.14% and 53.75 +/- 10.69% in the DD and MD groups, respectively. The 1 week post-test scores for the DD and MD groups were 81.67 +/- 8.57%, p < 0.001 and 78.75 +/- 4.43, p < 0.001 which was significantly higher than baseline. The 3-month score was significantly higher in the DD group, but not in the MD group (65.28 +/- 9.88%, p = 0.02 vs. 58.93 +/- 12.06%, p = 0.18). The absolute pre-test to 1-week post-test difference was significantly higher at 35.28 +/- 7.65% among participants in the DD group compared to 25.0 +/- 11.80% in the MD group, p = 0.048. Similarly, the absolute pre-test to 3-month post-test difference was significantly higher at 18.9 +/- 6.7% among the participants in the DD group, compared to 6.8 +/- 11.8% in the MD group, p = 0.021. CONCLUSIONS: Long-term nutrition knowledge is improved with DD compared with MD.

Hepatic lipid peroxidation and antioxidant micronutrients in hepatitis virus C liver recipients with and without disease recurrence.

BACKGROUND: Hepatitis C virus (HCV) reinfection after liver transplantation is universal and progresses to cirrhosis in 10% to 30% of patients. Several risk factors are associated with progression. Oxidative stress may be involved because it has a role in the pathogenesis of HCV. OBJECTIVE: To determine whether HCV liver recipients with disease recurrence are more oxidatively stressed than those with no recurrence. METHODS: Measurements were performed at 12 months posttransplantation, and in a subgroup of patients at 6 months. Liver lipid peroxidation (LPO), antioxidant potential, plasma vitamin E, retinol, and vitamin C were measured. Demographic data, pretransplantation viral load, anthropometry, and 3-day food records were also obtained. Data were log-transformed; analysis was performed using the independent t test, Pearson correlation, and multivariate regression analysis. RESULTS: Recipients of HCV livers with recurrence (n = 21) had higher liver LPO (mean [SEM] micromoles of malondialdehyde per gram of liver tissue, 1.66 [0.28]) vs those with no recurrence (n = 16; 0.88 [0.13]) (P = .02). A significant relationship was found between liver LPO and HCV recurrence, and this significance continued when accounting for pretransplantation viral load and donor age. Six patients with recurrence and 11 with no recurrence also had measurements obtained at 6 months posttransplantation. Those with recurrence at 12 months had significantly higher hepatic LPO at 6 months (1.86 [0.62]) compared with those with no recurrence (0.75 [0.14]) (P = .04). CONCLUSIONS: Recipients of HCV livers with recurrence are more oxidatively stressed at 6 and 12 months compared with those with no recurrence. Accounting for viral load and donor age, oxidative stress was independently associated with recurrence. More research is needed to confirm this association.

Oxidative stress and nutritional intakes in lung patients with bronchiolitis obliterans syndrome.

Survival after lung transplantation is limited by bronchiolitis obliterans syndrome (BOS). Oxidative stress (OxS) can be associated with BOS due to chronic inflammation. The type of fat and antioxidant intakes may also contribute to OxS. Our aim was to compare OxS and nutritional intakes in non-BOS versus various stages of BOS. Fifty-eight lung recipients with versus without BOS were prospectively classified as: non-BOS; BOS Op-1 (mild), and BOS 2-3 (severe). We measured nutritional intake and plasma vitamins A, C, and E. Among a subgroup of 37 patients, OxS was assessed by measuring lipid peroxidation (LPO micromol/L MDA) and oxidized glutathione (GSSG) in bronchoalveolar lavage BAL fluid (BALF). One-way analysis of variance was used to compare groups. Results are reported as mean values +/- standard errors of the mean. There was no significant difference in demographic features on time posttransplant among groups. Although there were comparable cell counts in BALF, severe BOS patients showed significantly higher BALF LPO concentrations when compared with milder stage of BOS or with non-BOS (P = .001, for both). Severe BOS recipients also displayed higher BALF GSSG concentrations compared to milder stage of BOS (P = .001) or non-BOS (P = .007). In conclusion, patients with severe BOS were more oxidatively stressed compared with mild and non-BOS recipients.

Metabolic bone disease in patients receiving home parenteral nutrition: a Canadian study and review.

BACKGROUND: Metabolic bone disease (MBD) is a significant complication in patients receiving long-term home parenteral nutrition (HPN). Pamidronate has been poorly studied in this population. We examine the prevalence and risk factors for MBD and examine changes in bone mineral density (BMD) after pamidronate administration. METHODS: First, a chart review of patients receiving HPN for >1 year was performed, and Pearson correlations were used to assess associations between MBD (defined as t score<-1) and risk factors. Second, the effect of IV pamidronate on BMD was studied prospectively in 11 HPN patients. Results were compared using a t-test. RESULTS: Charts were reviewed in 25 patients (15 F, 10 M): age, 56.9+/-3.1 years; body mass index (BMI), 21.2+/-0.57 kg/m2; months receiving HPN, 113.2+/-0.09; and days per week receiving HPN, 5.08+/-0.39. MBD was present in 33% of patients for the spine and hip and in 50% for the femoral neck; 24% had previous fractures. There was a significant negative correlation between the duration of HPN and BMD (r=-0.40) for all measurements. From those patients, 11 received IV pamidronate for a mean of 22.2+/-5.4 months. At baseline, their mean HPN treatment duration was 10.6+/-6.3 years. Overall, BMD results showed a trend toward improvement in the mean t score of the spine and hip postpamidronate therapy (pre, -3.1+/-0.75; post, -2.9+/-0.69; p=.07). After excluding 2 patients receiving corticosteroids, the mean t score of the spine showed significant improvement (prepamidronate -3.4+/-0.57 vs post-pamidronate -3.1+/-0.65, p=.036). CONCLUSIONS: In our HPN population, 76% had MBD and 24% had previous fractures. The results suggest that these patients may benefit from pamidronate. More studies are needed to assess the efficacy of pamidronate.

Effect of oral iron supplementation on oxidative stress and colonic inflammation in rats with induced colitis.

BACKGROUND: Iron supplementation may increase disease activity in ulcerative colitis, possibly through the production of reactive oxygen species from the Fenton reaction. AIM: To assess the effects of two doses of oral iron on intestinal inflammation and oxidative stress in experimental colitis. METHODS: Colitis was induced in rats by giving 5% dextran sulphate sodium in drinking water for 7 days. First, using a 2 x 2 factorial design, rats with or without dextran sulphate sodium received the regular diet or a diet containing iron 3%/kg diet. Second, rats with dextran sulphate sodium-induced colitis were supplemented with iron 0.3%/kg diet and compared with rats on dextran sulphate sodium and regular diet. The body weight change, histological scores, colon length, rectal bleeding, plasma and colonic lipid peroxides, colonic glutathione peroxidase and plasma vitamin E and C were measured. Faecal analysis for haem and total, free and ethylenediaminetetra-acetic acid-chelatable iron was also performed. RESULTS: Iron 3% and iron 0.3% increased the activity of dextran sulphate sodium-induced colitis, as demonstrated by higher histological scores, heavier rectal bleeding and further shortening of the colon. This was associated with increased lipid peroxidation and decreased antioxidant vitamins. Faecal iron available to the Fenton reaction was increased in a dose-dependent manner. CONCLUSIONS: Iron supplementation taken orally enhanced the activity of dextran sulphate sodium-induced colitis and is associated with an increase in oxidative stress.

Effects of ascites resolution after successful TIPS on nutrition in cirrhotic patients with refractory ascites.

OBJECTIVE: Malnutrition is common in patients with decompensated cirrhosis and refractory ascites. The use of transjugular intrahepatic portosystemic stent shunt (TIPS) is effective in eliminating ascites. The purpose of this study was to investigate the effect of TIPS and resolution of refractory ascites on the nutritional status of patients with decompensated cirrhosis. METHODS: Fourteen consecutive patients with refractory ascites and a Pugh score of 9.0+/-0.5 had a TIPS insertion. Biochemical data, resting energy expenditure (REE), total body nitrogen (TBN), body potassium (TBK), body fat (TBF), muscle force (MF), and food intake were recorded before TIPS, and at 3 and 12 months after the procedure. RESULTS: Ten patients completed the study. Baseline values for REE, TBN, TBF, MF, and energy intake were below normal at baseline. There was a significant increase in dry weight, TBN, and REE at 3 and 12 months compared with baseline. TBF improved significantly at 12 months. There was a trend toward an increase in energy intake (p = 0.072). There was no change in protein intake, TBK, MF, and Pugh score. CONCLUSION: In cirrhotic patients with refractory ascites, resolution of the ascites after TIPS placement resulted in improvement of several nutritional parameters, especially for body composition.

Lipid peroxidation and plasma antioxidant micronutrients in Crohn disease.

BACKGROUND: In Crohn disease (CD), the increased production of reactive oxygen species from activated neutrophils may reduce plasma concentrations of antioxidant vitamins and result in increased oxidative stress. OBJECTIVE: We compared lipid peroxidation, a measure of reactive-oxygen-species production, and plasma antioxidant vitamin concentrations between CD patients and healthy control subjects. DESIGN: Thirty-seven nonsmoking CD patients (22 women and 15 men) were compared with an equal number of healthy control subjects who were matched by age, sex, and body mass index. In patients the mean CD activity index (CDAI) was 141.2 +/- 18.7 (range: 9.0-514), and 11 of 37 patients (30%) had a CDAI > or =150. Seventy-eight percent of patients were taking > or = 1 medication. Medication use by subjects included the following: 5-aminosalicylic acid (40% of subjects), antibiotics (22%), oral corticosteroids (30%), and immunosuppressants (19%). RESULTS: Lipid peroxidation as measured by breath pentane output (CD patients, 7.47 +/- 0.98 pmol x kg(-1) x min(-1); control subjects, 4.97 +/- 0.48 pmol x kg(-1) x min(-1); P < or = 0.025), breath ethane output (CD patients, 11.24 +/- 1.17 pmol x kg(-1) x min(-1); control subjects, 5.46 +/- 0.71 pmol x kg(-1) x min(-1); P < or = 0.0005) and F2-isoprostane (CD patients, 78.6 +/- 8.0 ng/L; control subjects, 60.6 +/- 3.7 ng/L; P < or = 0.047) were significantly higher in CD patients than in control subjects. Plasma antioxidant vitamins (ascorbic acid, alpha- and beta-carotene, lycopene, and beta-cryptoxanthin) were all significantly lower in CD patients than in control subjects. There were no significant differences in macro- and micronutrient intakes between groups. CONCLUSION: Patients with CD are oxidatively stressed, which was observed even though 70% of patients had a CDAI < or =150 and 78% of them were taking medications to treat CD.

Effect of iron supplementation on oxidative stress and intestinal inflammation in rats with acute colitis.

In this study, we investigated the effect of intraperitoneal iron dextran (100 mg/100 g body weight) on oxidative stress and intestinal inflammation in rats with acute colitis induced by 5% dextran sulfate sodium. In both colitis and healthy animals, disease activity index, crypt and inflammatory scores, colon length, plasma and colonic lipid peroxides, and plasma vitamins E, C, and retinol were assessed. The results showed that iron-supplemented groups had moderate iron deposition in the colonic submucosa and lamina propria. In the colitis group supplemented with iron, colon length was significantly shorter; disease activity index, crypt, and inflammatory scores and colonic lipid peroxides were significantly higher; and plasma alpha-tocopherol was significantly lower compared to the colitis group without iron supplementation. There was no intestinal inflammation and no significant increase in colonic lipid peroxides in healthy rats supplemented with iron. In conclusion, iron injection resulted in an increased oxidative stress and intestinal inflammation in rats with colitis but not in healthy rats.

Role of cytomegalovirus infection in the incidence of viral acute respiratory infections in children attending day-care centers.

In a prospective study carried out in Lyon, France, the association between the excretion of cytomegalovirus (CMV) and the increasing frequency and severity of viral respiratory infections in children attending day-care centers was evaluated. Urine samples were collected in November 1992 (S1) and 4 months later in February 1993 (S4). A total of 246 children aged 6-12 months attending 29 day-care centers from 1 November to 28 February were screened for the excretion of CMV in urine. The diagnosis of viral acute respiratory infection was performed in the case of outbreaks only. Forty-eight (19.5%) children were both S1 and S4 positive for CMV, 30 (12.4%) became CMV positive (S1-/S4+), 4 (1.6%) became negative (S1+/S4-) and 164 (66.7%) remained negative. The percentage of children becoming CMV positive was significantly (P<0.001) higher in day-care centers where more than 40 children were enrolled. Nine outbreaks due to respiratory syncytial virus, rhinovirus and enterovirus were recorded in 8 of 29 (27.6%) day-care centers. Viral acute respiratory infections were significantly (P<0.05) more frequently recorded in day-care centers in which CMV and respiratory viruses cocirculated and were significantly (P<0.001) more frequently reported in CMV-infected children. These findings suggest that viral acute respiratory infections are significantly more likely to occur in CMV-infected children.

Breath alkanes as a marker of oxidative stress in different clinical conditions.

We assessed oxidative stress in three different clinical conditions: smoking, human immunodeficiency virus (HIV) infection, and inflammatory bowel disease, using breath alkane output and other lipid peroxidation parameters such as plasma lipid peroxides (LPO) and malondialdehyde (MDA). Antioxidant micronutrients such as selenium, vitamin E, C, beta-carotene and carotenoids were also measured. Lipid peroxidation was significantly higher and antioxidant vitamins significantly lower in smokers compared to nonsmokers. Beta-carotene or vitamin E supplementation significantly reduced lipid peroxidation in that population. However, vitamin C supplementation had no effect. In HIV-infected subjects, lipid peroxidation parameters were also elevated and antioxidant vitamins reduced compared to seronegative controls. Vitamin E and C supplementation resulted in a significant decrease in lipid peroxidation with a trend toward a reduction in viral load. In patients with inflammatory bowel disease, breath alkane output was also significantly elevated when compared to healthy controls. A trial with vitamin E and C is underway. In conclusion, breath alkane output, plasma LPO and MDA are elevated in certain clinical conditions such as smoking, HIV infection, and inflammatory bowel disease. This is associated with lower levels of antioxidant micronutrients. Supplementation with antioxidant vitamins significantly reduced these lipid peroxidation parameters. The results suggest that these measures are good markers for lipid peroxidation.