David Reffitt

Silicic acid: its gastrointestinal uptake and urinary excretion in man and effects on aluminium excretion

Silicon (Si), as silicic acid, is suggested to be the natural antidote to aluminium (Al) toxicity, and was recently shown to promote the urinary excretion of Al from body stores. The metabolism of Si in man, however, remains poorly investigated. Here we report on the pharmacokinetics and metabolism of Si in healthy volunteers following ingestion of orthosilicic acid (27-55 mg/l Si) in water. We also investigated whether orthosilicic acid promotes the urinary excretion of endogenous Al. Minimum, median uptake of Si from the ingested dose was 50.3% (range: 21.9-74.7%, n = 8) based on urinary analysis following dosing. Significant correlations were observed between creatinine clearance and Si levels in serum or urine (r = 0.95 and 0.99, respectively). Renal clearance of Si was 82-96 ml/min suggesting high renal filterability. These results suggest that orthosilicic acid is readily absorbed from the gastrointestinal tract of man and then readily excreted in urine. There was no significant increase in Al excretion, over 32 h, following ingestion of the orthosilicic acid dose (P = 0.5; n = 5).

Ferric trimaltol corrects iron deficiency anaemia in patients intolerant of iron

Oral iron supplements, which are usually in the form of ferrous (Fe2+) salts, are toxic to the gastrointestinal mucosa, and so intolerance is common, resulting in poor compliance and failure of treatment. The sugar derivative maltol strongly chelates iron, rendering it available for absorption and stabilized in the less toxic ferric (Fe3+) form.

Assessment of Iron Absorption from Ferric Trimaltol

Therapeutic iron compounds have limited absorption and often have side-effects, which limits patient compliance. Iron trimaltol is a novel, stable complex, formed between ferric iron (Fe3+) and maltol (3-hydroxy-2-methyl-4-pyrone), and is effective in the treatment of iron deficiency anaemia with few side-effects. However, the kinetics of iron absorption from ferric trimaltol and the reliability of normal colorimetric analysis in detecting iron absorbed from this complex have not been established. We measured increases in serum iron levels in 12 volunteers following oral challenge with four different pharmaceutical formulations of ferric trimaltol in a double-blind, cross-over, randomized study. The conventional colorimetric method for detecting serum iron was compared with thermal analyses after trichloroacetic acid (TCA) treatment of serum. Measurements of serum iron levels by TCA treatment and thermal analysis closely agreed with measurements by colorimetry. For all formulations, serum iron levels peaked at 90 min with a plateau of at least 5h [mean (standard deviation) peak absorption 8·3% (6·3%) of ingested dose, n = 48]. Absorption of iron, based on peak serum values or area under the serum curve, was not different for the four formulations (n = 12 each) and correlated with the individuals iron status, as assessed by serum ferritin values (r = −0·6; P < 0·001). Normal colorimetry is suitable for analysis of serum iron levels following ingestion of ferric trimaltol. There is rapid and sustained absorption of iron from ferric trimaltol and, as with ferrous iron, uptake appears to be controlled through normal mechanisms of iron acquisition that depend upon body iron stores.

Dedicated Barrett's surveillance sessions managed by trained endoscopists improve dysplasia detection rate

Background and study aim Barretts esophagus (BE)-associated dysplasia is an important marker for risk of progression to esophageal adenocarcinoma (EAC) and an indication for endoscopic therapy. However, BE surveillance technique is variable. The aim of this study was to assess the effect of dedicated BE surveillance lists on dysplasia detection rate (DDR). Patients and methods This was a prospective study of patients undergoing BE surveillance at two hospitals - community (UHL) and upper gastrointestinal center (GSTT). Four endoscopists (Group A) were trained in Prague classification, Seattle protocol biopsy technique, and lesion detection prior to performing BE surveillance endoscopies at both sites, with dedicated time slots or lists. The DDR was then compared with historical data from 47 different endoscopists at GSTT and 24 at UHL (Group B) who had undertaken Barretts surveillance over the preceding 5-year period. Results A total of 729 patients with BE underwent surveillance endoscopy between 2007 and 2012. There was no significant difference in patient age, sex, or length of BE between the two groups. There was a significant difference in detection rate of confirmed indefinite or low grade dysplasia and high grade dysplasia (HGD)/EAC between the two groups: 18 % (26 /142) Group A vs. 8 % (45/587) in Group B (P  < 0.001). Documentation of Prague criteria and adherence to the Seattle protocol was significantly higher in Group A. Conclusion This study demonstrated that a group of trained endoscopists undertaking Barretts surveillance on dedicated lists had significantly higher DDR than a nonspecialist cohort. These findings support the introduction of dedicated Barretts surveillance lists.

OC-039 Detection of dysplasia arising in barrett’s oesophagus is improved by trained endoscopists with a specialist interest and dedicated lists: Abstract OC-039 Table 1

Introduction Barrett’s oesophagus (BE) is the pre-malignant lesion to oesophageal adenocarcinoma (OAC). The presence of dysplasia, when diagnosed in surveillance programmes, is an important marker of risk of progression and an indication for endoscopic therapy. We have previously demonstrated that BE surveillance technique is variable and suggest centralised lists with few highly trained endoscopists. The aim of this study was to assess the introduction of dedicated BE surveillance lists on dysplasia detection rate (DDR). Method Prospective study of patients undergoing BE surveillance at two hospitals – district general hospital (DGH), and tertiary referral upper GI centre. A group of 4 endoscopists (group A) were trained in Prague classification, Seattle protocol biopsy technique and lesion detection. They were nominated to undertake BE surveillance, with dedicated time slots or lists. The DDR was then compared with historical data from 47 different endoscopists at GSTT (group B) and 24 at UHL (Group C) who had undertaken Barrett’s surveillance over the 5 year period. Analysis was by independent t-tests for continuous variables and chi-squared tests for categorical variables. Results A total of 729 patients with BE underwent endoscopy, between 2007 and 2012. Results are shown in Table 1. There was no significant difference in patient’s age, sex or length of BE between the three groups. Of these, 21% (30/144) were diagnosed with dysplasia/EAC by group A endoscopists vs. 9% (55/587) in Group B/C (p = 0.0004). There was a significant difference in detection rate of Indefinite or Low grade dysplasia (IND/LGD) and High grade dysplasia (HGD)/EAC between the 2 groups. There was a significant difference in diagnosis of IND in community (25/271) vs. teaching hospital (5/458) (p = 0.0001). Documentation of length of BE by Prague criteria was significantly higher in group A than group B&C. The use of High Resolution Endoscopy was similar between both groups.Abstract OC-039 Table 1 Study outcomes Gp A (n = 142) Gp B (n = 384) Gp C (n = 203) P value Age (+/- SEM) 62 (17) 61 (18) 63 (20) ns Sex (Male) 61% (87) 68% (261) 65% (131) ns Length (+/- IQR) 4.1 cm (0.37) 3.7 cm (0.15) 4.9 cm (0.29) ns HGD/OAC 8% (12) 3% (11) 2% (5) 0.0055 IND/LGD 13% (18) 3% (12) 13% (27) 0.0240 Prague documentation 93% (132/142) 16% (63) 16% (33) 0.0001 Conclusion This study demonstrates that a group of endoscopists trained in BE surveillance, have significantly higher dysplasia detection rate (DDR) than a non specialist cohort. These findings support the argument that BE surveillance, either at DGH or tertiary centre, should only be carried out on dedicated lists by trained endoscopists with a specialist interest. Disclosure of interest None Declared.

121 Detection of Dysplasia Arising in Barrett's Esophagus Is Improved by Trained Endoscopists With a Specialist Interest on Dedicated Lists

Introduction Barrett’s oesophagus (BE) is the pre-malignant lesion to oesophageal adenocarcinoma (OAC). The presence of dysplasia, when diagnosed in surveillance programmes, is an important marker of risk of progression and an indication for endoscopic therapy. We have previously demonstrated that BE surveillance technique is variable and suggest centralised lists with few highly trained endoscopists. The aim of this study was to assess the introduction of dedicated BE surveillance lists on dysplasia detection rate (DDR). Method Prospective study of patients undergoing BE surveillance at two hospitals – district general hospital (DGH), and tertiary referral upper GI centre. A group of 4 endoscopists (group A) were trained in Prague classification, Seattle protocol biopsy technique and lesion detection. They were nominated to undertake BE surveillance, with dedicated time slots or lists. The DDR was then compared with historical data from 47 different endoscopists at GSTT (group B) and 24 at UHL (Group C) who had undertaken Barrett’s surveillance over the 5 year period. Analysis was by independent t-tests for continuous variables and chi-squared tests for categorical variables. Results A total of 729 patients with BE underwent endoscopy, between 2007 and 2012. Results are shown in Table 1. There was no significant difference in patient’s age, sex or length of BE between the three groups. Of these, 21% (30/144) were diagnosed with dysplasia/EAC by group A endoscopists vs. 9% (55/587) in Group B/C (p = 0.0004). There was a significant difference in detection rate of Indefinite or Low grade dysplasia (IND/LGD) and High grade dysplasia (HGD)/EAC between the 2 groups. There was a significant difference in diagnosis of IND in community (25/271) vs. teaching hospital (5/458) (p = 0.0001). Documentation of length of BE by Prague criteria was significantly higher in group A than group B&C. The use of High Resolution Endoscopy was similar between both groups. Conclusion This study demonstrates that a group of endoscopists trained in BE surveillance, have significantly higher dysplasia detection rate (DDR) than a non specialist cohort. These findings support the argument that BE surveillance, either at DGH or tertiary centre, should only be carried out on dedicated lists by trained endoscopists with a specialist interest. Disclosure of interest None Declared.