title: Determination of large bowel length and loop complexity in patients with acromegaly undergoing screening colonoscopy.
abstract: BACKGROUND
  Patients with acromegaly are at moderately increased risk of developing colorectal cancer and may be considered for screening colonoscopy. In turn, large bowel dimensions may be increased in these patients, factors that predict for increased risk of serious complications such as perforation.
  
  
  OBJECTIVE
  To evaluate this risk potential, we measured large bowel length and loop complexity using magnetic endoscopic imaging (MEI).
  
  
  METHODS
  Case-control study in 25 unselected patients with acromegaly (mean age 56 years) vs. 41 nonacromegalic controls (mean age 60 years) undergoing screening colonoscopy.
  
  
  METHODS
  MEI parameters were determined and age- and sex-adjusted mean differences calculated. The dependency of total large bowel length on various demographic and disease-related factors (e.g. GH exposure, IGF-I and IGFBP-3 concentrations) was assessed using regression techniques.
  
  
  RESULTS
  Total large bowel length was increased by 20%[95% confidence interval (CI) 9-31%] in patients with acromegaly compared with controls (unadjusted and adjusted; P-values < 0.001). Acromegaly was also associated with increased time taken to reach the caecum (P = 0.01) and increased pelvic loop complexities (5/25 vs. 1/41, Fisher's exact test: P = 0.03). Total large bowel length was predicted by age at colonoscopy (P = 0.003) and patient height (P = 0.03), but not by surrogate biochemical markers of disease activity.
  
  
  CONCLUSIONS
  Acromegaly is associated with increased large bowel length and loop complexity making colonoscopy technically challenging, and theoretically increasing the risk of serious complications. Patients need to be counselled accordingly, and appropriate resources with experienced staff allocated.
authors.affiliation: Department of Surgery, Christie Hospital NHS Trust, Manchester, UK. arenehan@picr.man.ac.uk
authors.forename: Andrew G
authors.initials: AG
authors.lastname: Renehan
authors.forename: John E
authors.initials: JE
authors.lastname: Painter
authors.forename: G Duncan
authors.initials: GD
authors.lastname: Bell
authors.forename: Roger S
authors.initials: RS
authors.lastname: Rowland
authors.forename: Sarah T
authors.initials: ST
authors.lastname: O'Dwyer
authors.forename: Stephen M
authors.initials: SM
authors.lastname: Shalet
mesh_terms: D000172:Acromegaly / Q000150:complications / Q000473:pathology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000886:Anthropometry / Q000379:methods; D016022:Case-Control Studies; D002432:Cecum / Q000473:pathology; D003113:Colonoscopy / Q000009:adverse effects; D015179:Colorectal Neoplasms / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D006801:Humans; D007420:Intestine, Large / Q000473:pathology*; D008297:Male; D008403:Mass Screening / Q000009:adverse effects / Q000379:methods; D008875:Middle Aged; D018570:Risk Assessment / Q000379:methods; D012720:Severity of Illness Index