Utility of red flag symptom exclusions in the diagnosis of irritable bowel syndrome.
BACKGROUND
Studies suggest that the positive predictive value of the Rome II criteria for diagnosing irritable bowel syndrome can be enhanced by excluding red flag symptoms suggestive of organic diseases.


OBJECTIVE
We assessed the utility of red flags for detecting organic diseases in patients diagnosed irritable bowel syndrome by their physicians.


METHODS
Systematic chart reviews were completed in 1434 patients with clinical diagnoses of irritable bowel syndrome, abdominal pain, diarrhoea or constipation, who also completed questionnaires to identify Rome II criteria for irritable bowel syndrome and red flag symptoms.


RESULTS
The overall incidence of gastrointestinal cancer was 2.5% (but 1.0% in those with irritable bowel syndrome), for inflammatory bowel disease 2.0% (1.2% in irritable bowel syndrome), and for malabsorption 1.3% (0.7% in irritable bowel syndrome). Red flags were reported by 84% of the sample. The positive predictive value of individual red flags for identifying organic disease was 7-9%. Excluding any patient with a red flag improved the agreement between Rome II and clinical diagnosis by a modest 5%, but left 84% of patients who were diagnosed with irritable bowel syndrome by their physicians, without a diagnosis.


CONCLUSIONS
Red flags may be useful for identifying patients who require additional diagnostic evaluation, but incorporating them into the Rome criteria would not improve sensitivity and would result in too many missed irritable bowel syndrome diagnoses.
Whitehead
W E
WE
Center for Functional GI and Motility Disorders, Division of Gastroenterology and Hepatology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA. william_whitehead@med.unc.edu
Palsson
O S
OS
Feld
A D
AD
Levy
R L
RL
VON Korff
M
M
Turner
M J
MJ
Drossman
D A
DA
D000328:Adult; D003951:Diagnostic Errors / Q000517:prevention & control*; D005260:Female; D006801:Humans; D043183:Irritable Bowel Syndrome / Q000175:diagnosis*; D008297:Male; D008499:Medical Records / Q000592:standards; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires / Q000592:standards*