Medicine (St Vincent's) - Research Publications

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    Quality of upper GI endoscopy: a prospective cohort study on impact of endoscopist education
    Yang, LS ; Thompson, AJ ; Taylor, ACF ; Desmond, P ; Holt, BA (MOSBY-ELSEVIER, 2022-03)
    BACKGROUND AND AIMS: Guidelines on quality of upper GI (UGI) endoscopy have been proposed by the British Society of Gastroenterology (BSG) and European Society of Gastrointestinal Endoscopy (ESGE). However, these guidelines have not been evaluated in clinical practice. We aimed to measure the impact of endoscopist education on the quality of gastroscopy based on these guidelines and the association between compliance with guidelines and the detection of clinically significant premalignant pathology such as Barrett's esophagus (BE), esophageal squamous dysplasia, gastric intestinal metaplasia (GIM), and Helicobacter pylori. METHODS: Endoscopists participated in a 1-hour education session on recommended performance measures and endoscopic detection of premalignant pathologies. A controlled before and after study was performed, measuring compliance with guidelines and rates of detection of pathology in control and intervention groups. RESULTS: Over 2 years, 2719 procedures were performed: 1412 in the control group and 1307 in the intervention group. The proportion of procedures complying with guidelines was higher in the intervention group. The use of biopsy sampling protocols (eg, management of precancerous conditions of the stomach, 52% vs 91%; P = .007) and standardized terminology (eg, Forrest classification, 24% vs 68%; P < .001) was significantly higher. Detection of H pylori was higher in the intervention group (5.5% vs 9.8%, P = .003). Minimum inspection time of 7 minutes was associated with detection of BE (7.4% vs 2.0%, P < .001). CONCLUSIONS: A simple endoscopist education session enhanced the quality of UGI endoscopy by improving compliance with BSG and ESGE recommendations and increasing the detection of clinically significant pathology. A minimum inspection time of 7 minutes was associated with increased diagnostic yield and may be a feasible quality indicator for clinical practice.
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    Clinical application and diagnostic accuracy of artificial intelligence in colonoscopy for inflammatory bowel disease: systematic review
    Yang, LS ; Perry, E ; Shan, L ; Wilding, H ; Connell, W ; Thompson, AJ ; Taylor, ACF ; Desmond, P ; Holt, BA (GEORG THIEME VERLAG KG, 2022-07)
    Background and aims  Artificial intelligence (AI) technology is being evaluated for its potential to improve colonoscopic assessment of inflammatory bowel disease (IBD), particularly with computer-aided image classifiers. This review evaluates the clinical application and diagnostic test accuracy (DTA) of AI algorithms in colonoscopy for IBD. Methods  A systematic review was performed on studies evaluating AI in colonoscopy of adult patients with IBD. MEDLINE, Embase, Emcare, PsycINFO, CINAHL, Cochrane Library and Clinicaltrials.gov databases were searched on 28 th April 2021 for English language articles published between January 1, 2000 and April 28, 2021. Risk of bias and applicability were assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 tool. Diagnostic accuracy was presented as median (interquartile range). Results  Of 1029 records screened, nine studies with 7813 patients were included for review. AI was used to predict endoscopic and histologic disease activity in ulcerative colitis, and differentiation of Crohn's disease from Behcet's disease and intestinal tuberculosis. DTA of AI algorithms ranged between 52-91 %. The sensitivity and specificity for AI algorithms predicting endoscopic severity of disease were 78 % (range 72-83, interquartile range 5.5) and 91 % (range 86-96, interquartile range 5), respectively. Conclusions  AI has been primarily used to assess disease activity in ulcerative colitis. The diagnostic performance is promising and suggests potential for other clinical application of AI in IBD colonoscopy such as dysplasia detection. However, current evidence is limited by retrospective data and models trained on still images only. Future prospective multicenter studies with full-motion videos are needed to replicate the real-world clinical setting.
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    Factors that predict a poor response to radiofrequency ablation for Barrett's oesophagus with dysplasia
    Tsoi, EH ; Cameron, G ; Williams, R ; Desmond, P ; Taylor, A (WILEY, 2020-03)
    BACKGROUND: Radiofrequency ablation (RFA) can eradicate dysplasia and intestinal metaplasia in patients with dysplastic Barrett's oesophagus (BO). This study aimed to determine the factors that affect response to RFA for BO with dysplasia in a tertiary metropolitan referral centre. METHODS: All patients with dysplastic BO treated with regular proton pump inhibitor twice a day and RFA from November 2008 to July 2019 were identified. These patients were sorted into good responders (GR) (defined as eradication of dysplasia and intestinal metaplasia within three or less treatment sessions) and poor responders (PR) (defined as patients requiring four or more treatment sessions). The following features were compared between the groups: age, gender, presence of hiatus hernia, hiatus hernia size, circumferential and maximal length of BO, grade of dysplasia on histology at referral and presence of endoscopically visible reflux oesophagitis. RESULTS: A total of 152 patients received RFA for dysplastic BO, of whom 125 (82%) patients were classified as GR and 27 (18%) patients were classified as PR. PR had a longer circumferential length of BO compared to GR (mean length of 8.3 versus 3.3 cm, P < 0.0001). PR also had a longer maximal length of BO compared to GR (mean length of 8.7 versus 4.8 cm, P < 0.0001). More patients had reflux oesophagitis identified on gastroscopy in the PR group compared to GR group (12 (44%) versus 20 (16%), P = 0.001). CONCLUSION: Factors such as circumferential and maximal length of BO and presence of reflux oesophagitis on gastroscopy are associated with poorer response to RFA.
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    Recurrent intestinal metaplasia at the gastroesophageal junction following endoscopic eradication of dysplastic Barrett's esophagus may not be benign
    Cameron, GR ; Desmond, PV ; Jayasekera, CS ; Amico, F ; Williams, R ; Macrae, FA ; Taylor, ACF (GEORG THIEME VERLAG KG, 2016-08)
    BACKGROUND AND STUDY AIMS: Radiofrequency ablation (RFA) combined with endoscopic mucosal resection (EMR) is effective for eradicating dysplastic Barrett's esophagus. The durability of response is reported to be variable. We aimed to determine the effectiveness and durability of RFA with or without EMR for patients with dysplastic Barrett's esophagus. PATIENTS AND METHODS: Patients with dysplastic Barrett's esophagus referred to two academic hospitals were assessed with high definition white-light endoscopy, narrow-band imaging, and Seattle protocol biopsies. EMR was performed in visible lesions. RFA was performed at 3-month intervals until complete remission of dysplasia (CR-D) and intestinal metaplasia (CR-IM) was achieved. RESULTS: In total, 137 patients received RFA (78 with EMR); 75 with over 12 months follow-up since commencing RFA. Pretreatment histology was intramucosal cancer (IMC) 21 %, high grade dysplasia (HGD) 54 %, low grade dysplasia (LGD) 25 %. CR-D rates were 88 %, 92 %, and 100 % at 1, 2, and 3 years; CR-IM rates were 69 %, 74 %, and 81 %. Kaplan-Meier analysis showed increasing probability of achieving CR-D/CR-IM over time. Of 26 patients maintaining CR-IM for > 12 months, five relapsed with intestinal metaplasia (19 %), and three with dysplasia (12 %). Recurrences occurred in patients with prior HGD/IMC, predominantly at the gastroesophageal junction (GEJ). None relapsed with cancer. Adverse events occurred in 4 % of RFA and 6.5 % of EMR procedures. CONCLUSIONS: RFA combined with EMR is effective in achieving CR-D/CR-IM in the majority of patients with dysplastic Barrett's esophagus, with an incremental response over time. While durable in the majority, recurrent intestinal metaplasia and dysplasia, frequently occurring at the GEJ, suggest long-term surveillance is warranted in high risk groups.
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    Colonic mucosa-associated lymphoid tissue in a renal transplant recipient: a case report
    Martin, K ; Taylor, A ; Tam, C ; Hill, P ; Machet, D ; Goodman, D (BMC, 2020-06-28)
    BACKGROUND: Extra-gastric (particularly colonic) lymphoma of mucosa-associated lymphoid tissue in the immunosuppressed solid organ transplant recipient is rare. We report a case of low-volume mucosa-associated lymphoid tissue lymphoma with colonic and bone marrow involvement in a renal transplant recipient that has been managed conservatively. CASE PRESENTATION: A 62-year-old Caucasian man, 14 years after kidney transplantation, was diagnosed as having extra-nodal marginal zone lymphoma of mucosa-associated lymphoid tissue with bone marrow and colonic involvement, after a colonoscopy identified mucosa-associated lymphoid tissue lymphoma in a sessile sigmoid polyp following surveillance fecal occult blood testing that returned a positive result. A gastric biopsy showed no evidence of Helicobacter pylori, but Helicobacter pylori immunoglobulin G was positive. He received Helicobacter pylori eradication treatment and is being managed expectantly. Immunosuppression was unchanged with prednisolone, mycophenolate mofetil, and cyclosporine A. Renal allograft function has remained stable. CONCLUSIONS: This case highlights the unexpected occurrence of colonic mucosa-associated lymphoid tissue lymphoma in a kidney transplant recipient. The case emphasizes the importance of histopathological diagnosis of colonic lesions in this patient cohort because the unusual diagnosis of low-volume mucosa-associated lymphoid tissue lymphoma can be managed expectantly as it does not appear to be clinically aggressive in the immunosuppressed solid organ transplant.