Comparing the resource implications of old and new colorectal adenoma surveillance guidelines in Australia

BACKGROUND

The latest update to the Australian adenoma surveillance guideline in 2018 introduced a novel risk stratification system with updated surveillance recommendations. The resource implications of adopting this new system are unclear.

AIMS

To quanitfy the resource demands of adopting new over old adenoma surveillance guidelines.

METHODS

We studied data from 2443 patients undergoing colonoscopies, in which a clinically significant lesion was identified in their latest, or previous procedure(s) across five Australian hospitals. We excluded procedures with inflammatory bowel disease, new or prior history of colorectal cancer or resection, inadequate bowel preparation and incomplete procedures. Old and new Australian surveillance intervals were calculated according to the number, size and histological characteristics of lesions identified. We used these data to compare the rate of procedures according to each guideline.

RESULTS

Based on the procedures for 766 patients, the new surveillance guidelines significantly increased the number of procedures allocated an interval of 1 year (relative risk (RR): 1.57, P = 0.009) and 10 years (RR: 3.83, P < 0.00001) and reduced those allocated to half a year (RR: 0.08, P = 0.00219), 3 years (RR: 0.51, P < 0.00001) and 5 years (RR: 0.59, P < 0.00001). Overall, this reduced the relative number of surveillance procedures by 21% over 10 years (25.92 vs 32.78 procedures/100 patient-years), which increased to 22% after excluding patients 75 or older at the time of surveillance (19.9 vs 25.65 procedures/100 patient-years).

CONCLUSION

The adoption of the latest Australian adenoma surveillance guidelines can reduce demand for surveillance colonoscopy by more than a fifth (21-22%) over 10 years.

Post-traumatic stress disorder is associated with a higher rate of polypectomy independent of an increased frequency of colonoscopy in Australian veterans: a retrospective review

BACKGROUND

Post-traumatic stress disorder (PTSD) is associated with extensive physical comorbidities, including lower gastrointestinal symptoms. Diagnostic uncertainty and poor therapeutic responses may result in more frequent colonoscopies than clinically necessary. Polypectomy is standard practice when polyps are identified, and if PTSD is a risk factor for polyp formation, one would expect a higher rate of polyp detection and removal in veterans with PTSD than those without PTSD.

AIM

To determine the association between PTSD and the rate of colonoscopy and polypectomy in Australian veterans.

METHODS

Diagnostic and therapeutic colonoscopy rates in Australian male Veterans aged ≥50 years were examined by reviewing case records of veterans who accessed Department of Veterans' Affairs funded health services between 1 January 2013 and 31 December 2018.

RESULTS

A total of 138 471 veterans was included, of whom 28 018 had a diagnosis of PTSD; 56.4% were aged ≥65 years. Twenty-one percent of the entire cohort underwent at least one colonoscopy during the study period. Increased rates of diagnostic colonoscopy and polypectomy were associated with the presence of PTSD across all age brackets. The effect was empirically large as veterans with PTSD experience colonoscopy rates 76-81% greater than those without PTSD. Similarly, veterans with PTSD experienced polypectomy rates 76-81% greater than veterans without PTSD, and this increase persisted when controlling for the increased number of diagnostic colonoscopies they undergo.

CONCLUSION

The presence of PTSD has a marked impact on colonoscopy rates in Australian veterans. The increased polypectomy rate independent of increased colonoscopy rate suggests that PTSD is a risk factor for colonic polyp formation.

Quality of colonoscopy performed by medical or surgical specialists and trainees in five Australian hospitals

BACKGROUND

Ensuring colonoscopy procedure quality is vital to the success of screening and surveillance programmes for bowel cancer in Australia. However, the data on the performance of quality metrics, through adequate adenoma detection, bowel preparation, and procedure completion rates, in the Australian public sector is limited. Understanding these can inform quality improvement to further strengthen our capacity for prevention and early detection of colorectal cancer.

AIM

To determine the quality of colonoscopy in Australian teaching hospitals and their association with proceduralist specialty, trainee involvement, and location.

METHODS

We retrospectively evaluated 2443 consecutive colonoscopy procedure reports from 1 January to 1 April, 2018 from five public teaching tertiary hospitals in Australia (median 60 years old, 49% male). Data for bowel preparation quality, procedure completion rates, and detection rates of clinically significant adenomas, conventional adenomas, and serrated lesions was collected and compared to national criteria for quality in colonoscopy. Participating hospital, proceduralist specialty, and trainee involvement indicators were used for stratification. Data was analysed using Chi-squared tests of independence, Mann-Whitney U, One-way ANOVA, and multivariate binary logistic regression.

RESULTS

Fifty-two point two percent (n = 1276) and 43.3% (n = 1057) were performed by medical and surgical proceduralists respectively, whilst 29.8% (n = 728) involved a trainee. Inadequate bowel preparation affected 7.3% of all procedures. The procedure completion rate was 95.1%, which increased to 97.5% after adjustment for bowel preparation quality. The pooled cancer, adenoma, and serrated lesion detection rates for all five hospitals were 3.5%, 40%, and 5.9% respectively. Assessed hospitals varied significantly by patient age (P < 0.001), work-force composition (P < 0.001), adequacy of bowel preparation (P < 0.001), and adenoma detection rate (P < 0.001). Two hospitals (40%) did not meet all national criteria for quality, due to a procedure completion rate of 94.5% or serrated lesion detection rate of 2.6%. Although lower than the other hospitals, the difference was not significant. Compared with surgical specialists, procedures performed by medical specialists involved older patients [65 years (inter-quartile range, IQR 58-73) vs 64 years (IQR 56-71); P = 0.04] and were associated with a higher adenoma detection rate [odds ratio (OR) 1.53; confidence interval: 1.21-1.94; P < 0.001]. Procedures involving trainee proceduralists were not associated with differences in the detection of cancer, adenoma, or serrated lesions, compared with specialists, or according to their medical or surgical background. On multivariate analysis, cancer detection was positively associated with patient age (OR 1.04; P < 0.001) and negatively associated with medical compared to surgical proceduralists (OR 0.54; P = 0.04). Conventional adenoma detection rates were independently associated with increasing patient age (OR 1.04; P < 0.001), positively associated with medical compared to surgical proceduralists (OR 1.41; P = 0.002) and negatively associated with male gender (OR 0.53; P < 0.001).

CONCLUSION

Significant differences in the quality of colonoscopy in Australia exist, even when national benchmarks are achieved. The role of possible contributing factors, like procedural specialty and patient gender need further evaluation.

Body mass index is inversely associated with capillary ketones at the time of colonoscopy: Implications for SGLT2i use

OBJECTIVE

Sodium-glucose cotransporter 2 inhibitors (SGLT2i) have been associated with diabetic ketoacidosis at the time of colonoscopy. This study aimed to identify factors associated with ketone concentrations in SGLT2i-treated type 2 diabetes compared with non-SGLT2i-treated diabetes, and those with impaired fasting glycaemia (IFG) and normoglycaemia.

DESIGN

Cross-sectional, multicentre, observational study June-December 2020 in four Australian tertiary hospitals.

PARTICIPANTS

Capillary glucose and ketones were measured in people undergoing colonoscopy: 37 SGLT2i-treated and 105 non-SGLT2i-treated type 2 diabetes, 65 IFG and 151 normoglycaemia.

MEASUREMENTS

Body mass index (BMI), age, glucose, fasting duration and where relevant, HbA1c and time since last SGLT2i dose.

RESULTS

In SGLT2i-treated diabetes, BMI (ρ = -0.43 [95% confidence interval: -0.67, -0.11]) and duration since last SGLT2i dose (ρ = -0.33 [-0.60, 0.00]) correlated negatively with increasing ketones, but there was no correlation with fasting duration. In non-SGLT2i-treated diabetes, BMI correlated negatively (ρ = -0.24 [-0.42, -0.05]) and fasting duration positively (ρ = 0.26 [0.07, 0.43]) with ketones. In IFG participants, only fasting duration correlated with ketones (ρ = 0.28 [0.03, 0.49]). In normoglycaemic participants, there were negative correlations with BMI (ρ = -0.20 [-0.35, -0.04]) and fasting glucose (ρ = -0.31 [-0.45, -0.15]) and positive correlations with fasting duration (ρ = 0.20 [0.04, 0.35]) and age (ρ = 0.19 [0.03, 0.34]). Multiple regression analysis of the entire cohort showed BMI, age and fasting glucose remained independently associated with ketones, but in SGLT2i-treated participants only BMI remained independently associated.

CONCLUSIONS

In SGLT2i-treated diabetes, lower BMI was a novel risk factor for higher ketones precolonoscopy. Pending larger confirmatory studies, extra vigilance for ketoacidosis is warranted in these people.

Software Analysis of Colonoscopy Videos Enhances Teaching and Quality Metrics

Purpose

Machine learning algorithms were hypothesized as being able to predict the quality of colonoscopy luminal images. This is to enhance training and quality indicators in endoscopy.

Methods

A separate study involving a randomized controlled trial of capped vs. un-capped colonoscopies provided the colonoscopy videos for this study. Videos were analyzed with an algorithm devised by the Australian Institute for Machine Learning. The image analysis validated focus measure, steerable filters-based metrics (SFIL), was used to assess luminal visualization quality and was compared with two independent clinician assessments (C1 and C2). Goodman and Kruskal's gamma (G) measure was used to assess rank correlation data using IBM SPSS Statistics for Windows, version 25.0 (IBM Corp., Armonk, NY).

Results

A total of 500 random colonoscopy video clips were extracted and analyzed, 88 being excluded. SFIL scores matched with C1 in 45% and C2 in 42% of cases, respectively. There was a significant correlation between SFIL and C1 (G = 0.644, p < 0.005) and SFIL and C2 (G = 0.734, p < 0.005).

Conclusion

This study demonstrates that machine learning algorithms can recognize the quality of luminal visualization during colonoscopy. We intend to apply this in the future to enhance colonoscopy training and as a metric for quality assessment.

Current endoscopic closure techniques for the management of gastrointestinal perforations

Acute gastrointestinal perforations occur either from spontaneous or iatrogenic causes. However, particular attention should be made in acute iatrogenic perforations as timely diagnosis and endoscopic closure prevent morbidity and mortality. With the increasing use of diagnostic endoscopy and advances in therapeutic endoscopy worldwide, the endoscopist must be able to recognize and manage perforations. Depending on the size and location of the defect, a variety of endoscopic clips, stents, and suturing devices are available. This review aims to prepare and guide the endoscopist to use the right tools and techniques for optimal patient outcomes.

The effect of socioeconomic deprivation on presentation stage and long-term outcomes in patients undergoing colorectal cancer resection in Western Sydney

BACKGROUND

While socioeconomic deprivation has been shown to affect survival in colorectal cancer, other factors such as global region of birth and ethnicity also exert an effect. We wished to ascertain the influence of socioeconomic deprivation on stage of presentation and cancer survival in an ethnically diverse Australian population.

METHODS

Cases from a database of resections in Western Sydney (n = 1596) were stratified into cohorts of socioeconomic quintiles. Univariate analysis was used to compare demographics, AJCC stage and histopathological details between the least and most socioeconomically deprived groups. Kaplan-Meier analysis and log-rank testing were used to compare cancer-specific and all-cause 5-year survival between the most deprived quintile and all others, after case-control matching for age and overseas birth.

RESULTS

A total of 322 (20.2%) patients from the most socioeconomically deprived centile, and 275 (17.2%) from the least were compared. The most deprived were significantly more likely to be aged under 70 (54.1% vs. 44.4%, p = 0.019), born overseas (54.3% vs. 38.6%, p = 0.003), present with stage III disease (37.4% vs. 26.7%, p = 0.005), perforated (12.5% vs. 5.3%, p = 0.005) or circumferential tumours (37% vs. 24.3%, p = 0.043). There was no significant difference in proportions presenting with metastatic disease, or 5-year survival between the most deprived quintile and all others after correction for age and foreign birth.

CONCLUSIONS

Socioeconomic deprivation is associated with unfavourable colorectal cancer presentation stage but not poorer 5-year survival in our Western Sydney population. The reasons for this are unclear and demand further attention.

A case report of iatrogenic gas gangrene post colonoscopy successfully treated with conservative management- is surgery always necessary?

Background

Colonoscopy is a routine procedure in diagnosis and treatment of colonic disease. While generally regarded as a safe procedure, potentially fatal complications can occur. Gas gangrene is one such complication, with very high mortality. There are few cases of gas gangrene occurring after colonoscopy, making it one of the rarer complications of this procedure. There have been no previously reported cases of a patient surviving such an infection and the optimal treatment strategy is contentious. This report describes a case of intramural gas gangrene of the colon, treated conservatively with antibiotic therapy in which the patient survived with full recovery.

Case presentation

A 71-year-old, previously healthy male presented 6 h post apparently uncomplicated colonoscopic polypectomy with rigors, nausea, vomiting and right upper quadrant pain. At presentation he was febrile at 40.1 °C but hemodynamically stable. Abdominal computed tomography revealed substantial colonic thickening and several focal intramural gas bubbles (pneumatosis intestinalis) surrounding the polypectomy site. Within 24 h post procedure he became hypotensive and was admitted to ICU in frank septic shock requiring inotropes, and with demonstrable septic myocardial depression. Bloods showed multi-organ derangement with leukocytosis, lactic acidosis, haemolytic anaemia and hyperbilirubinemia. A diagnosis of presumed Clostridial gas gangrene was made, and treatment was initiated with benzylpenicillin, clindamycin, metronidazole and vancomycin. After 4 days in ICU he was stepped down, and discharged after a further 10 days with no surgical or endoscopic interventions. At three-month review he reported being back to full health.

Conclusions

This case demonstrates that gas gangrene infection is a possible complication of colonoscopic polypectomy. This is a cause of rapid deterioration in post-colonoscopy patients and has been misdiagnosed as colonic perforation in previously reported cases of retroperitoneal gas gangrene. Such misdiagnosis delays antibiotic therapy, which likely plays a role in the high mortality of this condition. Early diagnosis and initiation of antibiotic therapy with benzylpenicillin and clindamycin as seen in this case is essential for patient survival. While surgery is typically performed, non-operative management of pneumatosis intestinalis, and potentially gas gangrene is becoming more common and was utilized effectively in this patient.