Wherever I may roam-Human activity alters movements of red deer (Cervus elaphus) and elk (Cervus canadensis) across two continents

Human activity and associated landscape modifications alter the movements of animals with consequences for populations and ecosystems worldwide. Species performing long-distance movements are thought to be particularly sensitive to human impact. Despite the increasing anthropogenic pressure, it remains challenging to understand and predict animals' responses to human activity. Here we address this knowledge gap using 1206 Global Positioning System movement trajectories of 815 individuals from 14 red deer (Cervus elaphus) and 14 elk (Cervus canadensis) populations spanning wide environmental gradients, namely the latitudinal range from the Alps to Scandinavia in Europe, and the Greater Yellowstone Ecosystem in North America. We measured individual-level movements relative to the environmental context, or movement expression, using the standardized metric Intensity of Use, reflecting both the directionality and extent of movements. We expected movement expression to be affected by resource (Normalized Difference Vegetation Index, NDVI) predictability and topography, but those factors to be superseded by human impact. Red deer and elk movement expression varied along a continuum, from highly segmented trajectories over relatively small areas (high intensity of use), to directed transitions through restricted corridors (low intensity of use). Human activity (Human Footprint Index, HFI) was the strongest driver of movement expression, with a steep increase in Intensity of Use as HFI increased, but only until a threshold was reached. After exceeding this level of impact, the Intensity of Use remained unchanged. These results indicate the overall sensitivity of Cervus movement expression to human activity and suggest a limitation of plastic responses under high human pressure, despite the species also occurring in human-dominated landscapes. Our work represents the first comparison of metric-based movement expression across widely distributed populations of a deer genus, contributing to the understanding and prediction of animals' responses to human activity.

Development of a core descriptor set for Crohn's anal fistula

AIM

Crohn's anal fistula (CAF) is a complex condition, with no agreement on which patient characteristics should be routinely reported in studies. The aim of this study was to develop a core descriptor set of key patient characteristics for reporting in all CAF research.

METHOD

Candidate descriptors were generated from published literature and stakeholder suggestions. Colorectal surgeons, gastroenterologists and specialist nurses in inflammatory bowel disease took part in three rounds of an international modified Delphi process using nine-point Likert scales to rank the importance of descriptors. Feedback was provided between rounds to allow refinement of the next ratings. Patterns in descriptor voting were assessed using principal component analysis (PCA). Resulting PCA groups were used to organize items in rounds two and three. Consensus descriptors were submitted to a patient panel for feedback. Items meeting predetermined thresholds were included in the final set and ratified at the consensus meeting.

RESULTS

One hundred and thirty three respondents from 22 countries completed round one, of whom 67.0% completed round three. Ninety seven descriptors were rated across three rounds in 11 PCA-based groups. Forty descriptors were shortlisted. The consensus meeting ratified a core descriptor set of 37 descriptors within six domains: fistula anatomy, current disease activity and phenotype, risk factors, medical interventions for CAF, surgical interventions for CAF, and patient symptoms and impact on quality of life.

CONCLUSION

The core descriptor set proposed for all future CAF research reflects characteristics important to gastroenterologists and surgeons. This might aid transparent reporting in future studies.

Ileo-anal pouch excision and permanent ileostomy - Indications and outcomes from a tertiary centre

PURPOSE

Pouch excision is a major complication of ileoanal pouch surgery. Current practice is for this type of surgery to be performed in a specialist centre. We present a series of patients undergoing pouch excision surgery in a high volume centre in the UK and assess the outcomes in these patients.

METHODS

All patients undergoing pouch excision at the Royal Liverpool Hospital between 1995 and 2015 under the care of a single surgeon were included. Demographics and outcomes were taken from patients' notes and a dedicated retrospectively compiled database.

RESULTS

35 patients underwent pouch excision surgery during this period. Around half the patients had their original pouch surgery elsewhere and were referred for management of complications. Median time to pouch excision was 13 years from the original operation. Overall complication rate was 31% with 11% requiring re-intervention post-operatively. There was no mortality in this series.

CONCLUSION

Pouch excision is a complex, high-risk procedure that should be carried out in specialist centres. Our series shows that in such settings, good outcomes can be achieved for these patients.

Clinical follow-up does not improve survival after resection of stage I-III colorectal cancer: A cohort study

INTRODUCTION

The benefit of clinical follow-up alongside CT & CEA in detecting recurrent colorectal cancer (CRC) remains unclear. Despite this, clinical review remains part of most surveillance protocols. This study assessed the efficacy of clinical follow-up in addition to CT/CEA in detecting disease recurrence.

METHODS

Patients undergoing surgery for CRC at a single centre between 2009 and 2011 were identified. Follow-up included clinical review, CT and CEA for 5 years. The primary endpoint of the study was method of detection of recurrence. Secondary endpoints included detection of surgically treatable recurrence, compliance with follow-up, disease free survival and overall survival.

RESULTS

118 patients with stage I-III CRC were included. Only 68.9% of scheduled follow-up events were performed (76.6% clinical reviews, 76.2% CT scans and 60.4% CEA tests). At median follow-up of 36 months, 26 patients had developed recurrence (median DFS 45.8 months). 17 patients (14.7%) had died (median OS 49.3 months). Sensitivity and specificity of follow up modality in detecting recurrence were; CT (92.3%, 100%), CEA (57.7%, 100%), clinical review (23.0%, 27.2%). Addition of clinical review did not identify any disease recurrence that was not detected by scheduled CT. Eight patients (30.7%) had surgically treatable recurrence - all were identified by scheduled CT.

CONCLUSION

The addition of CEA testing and clinical review to scheduled CT scanning offered no benefit in the detection of recurrent disease. Clinical review could be removed from follow-up protocols without any reduction in the detection of recurrent cancer.

Renal cell carcinoma metastases to gallbladder

A 74-year old man underwent a radical cholecystectomy for presumed gallbladder cancer. The histology of the resected specimen in fact revealed the lesion to be metastatic renal cell carcinoma from his resected right nephrectomy performed 14 years previously.

Routine staging laparoscopy has no place in the management of colorectal liver metastases

AIMS

Staging laparoscopy has been recommended in the management of patients with colorectal liver metastases prior to hepatectomy in order to reduce the incidence and associated morbidity of futile laparotomies. The utility of staging laparoscopy has not been assessed in patients undergoing CT, PET-CT and MRI as standard preoperative staging.

METHODS

All patients undergoing attempted open hepatectomy for colorectal liver metastases between 1/4/2008 and 31/3/2012 were identified from a prospectively maintained research database. All patients who underwent futile laparotomy were identified, with demographics and operative notes subsequently analysed.

RESULTS

A total of 274 patients underwent attempted open hepatectomy during the study period. At laparotomy 12 (4.4%) patients were found to have irresectable disease. There were no unifying demographic factors within the patients undergoing futile laparotomy.

CONCLUSIONS

With modern imaging, the potential yield of staging laparoscopy is low. Staging laparoscopy should not be used routinely, but may have a role in the case of specific clinical concerns.

Intermittent small bowel obstruction caused by Meckel's enterolith

A 56-year-old man presented with small bowel obstruction after a 6-week history of intermittent resolving subacute small bowel obstruction. After investigations, he underwent laparotomy. A mobile, narrow-necked Meckel's diverticulum packed with enteroliths pressing against proximal small bowel was discovered. A small bowel resection was performed.