Can the systematic use of non-invasive biomarkers in patients with lower gastrointestional sysmtpoms help rationalise the demand for limited endoscopy resources?
Citation:
ALAKKARI, ALAA, Can the systematic use of non-invasive biomarkers in patients with lower gastrointestional sysmtpoms help rationalise the demand for limited endoscopy resources?, Trinity College Dublin.School of Medicine, 2020Download Item:
Abstract:
Introduction: Gastrointestinal complaints are very common in the general
population. Demand for endoscopy continues to outstrip capacity, despite significant
annual increase in the number of endoscopies performed nationwide, leading to
expanding waiting lists, and potential delay in significant diagnoses.
Hypothesis: We hypothesised that the demand on endoscopy can be optimised
using investigation algorithms for common lower gastrointestinal complaints through
the systematic use of a combination of non-invasive serum and faecal biomarkers.
Methods: One retrospective and two prospective studies were carried out focusing
on Colonoscopy outcomes in patients with lower GI symptoms and asymptomatic
surveillance patients, to explore the above hypothesis looking at CRP, Faecal
Calprotectin, symptom based diagnostic questionnaire and Faecal CologuardTM. We
also performed a patient survey to examine potential factors influencing patient
compliance with faecal testing.
Results: Both retrospective and prospective studies of symptomatic patients showed
mucosal inflammation was significantly associated with diarrhoea (p=0.008). Most
Colonoscopies showed no evidence of inflammation, especially in patients with nondiarrhoeal symptoms (79-93%). Raised FCal (>50 ug/g) was strongly associated with
inflammation (OR = 10.59), with a stronger relationship between inflammation and
FCal >100 ug/g (OR=15.66). ROC curve suggested the diagnostic model of age,
gender, F Cal and the questions relating to frequent loose/ mushy stool was best at
predicting inflammation. FCal-CRP score was found to be very strongly associated
with mucosal inflammation. The incidence of adenomas was low in young patients
(8.7% ADR) compared to 24.7% in older symptomatic patients and 35.7% in
surveillance patients. Faecal CologuardTM performed poorly in our study with NPV
and PPV of 77.5% and 40%, with a sensitivity and specificity of 30.8% and 83.8%,
respectively.
Conclusion: We recommend the use of integrated investigation pathways that
include a validated clinical symptom questionnaire, non-invasive serum and faecal
inflammatory biomarkers in the initial assessment of patients referred with non-?red
flag? lower gastrointestinal symptoms prior to referral for Colonoscopy. This allows
accurate triage of patients who require Colonoscopy and those who can be
reassured without the need for it, or who may have an alternative organic cause for
their symptoms.
A potential diagnostic algorithm extrapolated from our data, for young patient with
diarrhoea is; exclude Coeliac disease and hyperthyroidism, check FCal-CRP score,
and if all are negative, do not refer for Colonoscopy, and consider management in
primary care. Colonoscopy may be avoided in young patients with non-diarrhoeal
symptoms (Constipation, abdominal pain and bloating). For older patients with
diarrhoea the same model can be applied, with the addition of a validated faecal
marker for adenomatous polyps and CRC. Patient compliance with faecal testing
remains a major limiting factor to the successful implementation of such pathways.
Author's Homepage:
https://tcdlocalportal.tcd.ie/pls/EnterApex/f?p=800:71:0::::P71_USERNAME:AALAKKARDescription:
APPROVED
Author: ALAKKARI, ALAA
Advisor:
Ryan, BarbaraPublisher:
Trinity College Dublin. School of Medicine. Discipline of Clinical MedicineType of material:
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