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Irritable bowel syndrome and coeliac disease
CORRESPONDENCE
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Hoffmann WH, Blanke CH, Maier JM, et al. Antigenicity and specificity of very low molecular weight Onchocerca volvulus polypeptides in the range 2·2–12·5kD. Trop Med Int Health 1997; 7: 635–45. Gallin MY, Jacobi AB, Büttner DW, et al. Human autoantibody to defensin: disease association with hyperreactive onchocerciasis (sowda). J Exp Med 1995; 182: 41–47. Cabrera Z, Büttner DW, Parkhouse RME. Unique recognition of a low molecular weight Onchocerca volvulus antigen by IgG3 antibodies in chronic hyper-reactive onchodermatitis (sowda). Clin Exp Immunol 1988; 74: 223–29.
Irritable bowel syndrome and coeliac disease Sir—David Sanders and colleagues (Nov 3, p 1504)1 report that 14 of 300 secondary-care patients fulfilling the ROME II criteria for irritable bowel syndrome (IBS) had coeliac disease. Their data provoke many questions to be considered before their conclusions can be accepted. The ROME II criteria were never meant to be used in the absence of clinical judgment. Used wisely, they can help guide physicians to a positive diagnosis. They cannot replace the complex amalgam of skill, learning, care, and intuition that should characterise clinical practice. The criteria are accompanied by exhortation to take a careful history, do a physical examination, and specifically to look for alarm symptoms that could suggest structural disease.2 Sanders and colleagues mention sinister symptoms as exclusion criteria, but can we be sure they were absent in patients who were diagnosed as having coeliac disease? When asked about the ROME criteria were patients also specifically asked about continuous diarrhoea, weight loss, nutritional defects, family history, and so on? Did they have characteristics that might help doctors identify IBS patients at risk for coeliac disease? Duodenal histology characteristic of coeliac disease does not necessarily negate a diagnosis of IBS. Did the IBS symptoms vanish on a gluten-free diet? In their table 1, Sanders and colleagues show data suggesting that 26% of ROME-II-positive patients have disorders other than IBS, but is that true? 6% were lost to follow-up, 5% had diverticular disease—surely not a cause of ROME II symptoms3—and many of the remaining disorders, such as infective enteritis, alcoholic diarrhoea, radiation enteritis, and IBS should have been clinically suspected by a careful doctor. How old were the patients with rectal carcinoma or colon
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polyps? Would they not have been picked up routinely on colon examination that the researchers say is normally done in patients older than 45 years and is recommended by ROME? Do the researchers think the polyps caused the IBS symptoms? Sanders and colleagues are correct to raise our sensitivity to coeliac disease, and their advocacy for early diagnosis is convincing. However, in addition to omission of clinical clues, there are two important issues that they do not discuss. IBS is the most common disorder seen in gastrointestinal clinics worldwide. What would be the cost of implementing their suggestion that a panel of immunological tests be part of an IBS work-up? Do they think that ROME III should add a negative result with such tests as a criterion for IBS? Perhaps the most important issue is the implication that recommendations for automatic testing could return us to the bad old days when IBS was deemed a diagnosis of exclusion. This attitude is damaging. No test or set of diagnostic criteria is infallible. Every patient deserves careful consideration of their complaints, and neither rote application of ROME II nor immunological tests for coeliac disease will serve. If they did, gastroenterologists could be replaced by computers and save a great deal of money—more than enough for the immunological tests. W Grant Thompson University of Ottawa, Ottawa, Ontario K2H 8C4, Canada 1
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Sanders DS, Carter MJ, Hurlstone DP, et al. Association of adult coeliac disease with irritable bowel syndrome: a case-control study in patients fulfilling ROME II criteria referred to secondary care. Lancet 2001; 358: 1504–08. Thompson WG, Longstreth GF, Drossman DA, Heaton KW, Irvine EJ, Muller-Lissner SA. Functional bowel disorders and D functional abdominal pain. In: Drossman DA, Coraniari E, Talley NJ, Thompson WG, Whitehead WE, eds. The functional gastrointestinal disorders, 2nd edn. Washington: Degnon, 2000. Thompson WG, Patel DG. Clinical picture of diverticular disease of the colon. Clin Gastroenterol 1986; 16: 903–16.
Sir—One interpretation of the paper on the association between coeliac disease and IBS by David Sanders and colleagues1 is that there is a worrying 20–25% chance of missing organic disease with use of the ROME II criteria. This finding highlights the limitations of the these criteria as a dependable diagnostic tool. Furthermore, 14 of 300 patients turned out to have unsuspected coeliac disease. This number contrasts with two primary-care studies,2,3 in which no case of coeliac disease was
identified among 121 and 132 patients with IBS. In the study done by myself and other workers,3 we used Manning’s criteria to identify IBS, although the family physicians’ adherence to these were loose in several cases. Valori4 describes such cases as having odd symptoms that cannot be classified in neat diagnostic groups—a common difficulty in primary care. Patients referred to secondary care therefore differ from most of those who present in primary care. Sanders and colleagues’ cohort, for example, has a median age of 56 years with a sex ratio of 1:2·5. This ratio differs from the picture of IBS in primary care, in which Thompson5 noted an overwhelming 86% to be women (male to female ratio of 1:6), which is in keeping with most family physicians’ experiences. The surprising number of men (86 of 300 cases) in Sanders and colleagues’ study suggests that the selection of patients by the ROME II criteria does not reflect the general population prevalence of IBS and that the criteria do not help to distinguish with confidence patients with functional from those with organic disease. However, this study does highlight once again the emerging “look and you will find” picture of the coeliac iceberg that emerges via serological testing. Since serology is now cheap and accessible in primary care, family physicians probably should screen for coeliac disease patients with IBS who are being referred to secondary care, as Sanders and colleagues suggest. I suspect, however, that the detection rate will be far lower than that reported, since family physicians do not generally use the ROME II criteria for the diagnosis of this common disorder. Successful detection, after all, is knowing where to look. Harold Hin Hightown Surgery, Banbury, Oxford OX16 9DB, UK 1
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Sanders DS, Carter MJ, Hurlstone DP, et al. Association of adult coeliac disease with irritable bowel syndrome: a case-control study in patients fulfilling ROME II criteria referred to secondary care. Lancet 2001; 358: 1504–08. Holt R, Darnley S, Kennedy T, Jones R. Screening for celiac disease in patients with clinical diagnosis of irritable bowel syndrome. Gastroenterology 2001; 120 (suppl 1): A757 (abstr 4064). Hin H, Bird AJ, Fisher P, Maby N, Jewell D. Coeliac disease in primary care: case finding study. BMJ 1999; 318: 164–67. Valori R. Coeliac disease in patients with irritable bowel syndrome. Lancet 2001; 358: 1475. Thompson WG, Heaton KW, Smyth GT, Smyth C. Irritable bowel syndrome in general practice: prevalence, characteristics and referral. Gut 2000; 46: 7882.
THE LANCET • Vol 359 • April 13, 2002 • www.thelancet.com
For personal use. Only reproduce with permission from The Lancet Publishing Group.
3
4
5
Hoffmann WH, Blanke CH, Maier JM, et al. Antigenicity and specificity of very low molecular weight Onchocerca volvulus polypeptides in the range 2·2–12·5kD. Trop Med Int Health 1997; 7: 635–45. Gallin MY, Jacobi AB, Büttner DW, et al. Human autoantibody to defensin: disease association with hyperreactive onchocerciasis (sowda). J Exp Med 1995; 182: 41–47. Cabrera Z, Büttner DW, Parkhouse RME. Unique recognition of a low molecular weight Onchocerca volvulus antigen by IgG3 antibodies in chronic hyper-reactive onchodermatitis (sowda). Clin Exp Immunol 1988; 74: 223–29.
Irritable bowel syndrome and coeliac disease Sir—David Sanders and colleagues (Nov 3, p 1504)1 report that 14 of 300 secondary-care patients fulfilling the ROME II criteria for irritable bowel syndrome (IBS) had coeliac disease. Their data provoke many questions to be considered before their conclusions can be accepted. The ROME II criteria were never meant to be used in the absence of clinical judgment. Used wisely, they can help guide physicians to a positive diagnosis. They cannot replace the complex amalgam of skill, learning, care, and intuition that should characterise clinical practice. The criteria are accompanied by exhortation to take a careful history, do a physical examination, and specifically to look for alarm symptoms that could suggest structural disease.2 Sanders and colleagues mention sinister symptoms as exclusion criteria, but can we be sure they were absent in patients who were diagnosed as having coeliac disease? When asked about the ROME criteria were patients also specifically asked about continuous diarrhoea, weight loss, nutritional defects, family history, and so on? Did they have characteristics that might help doctors identify IBS patients at risk for coeliac disease? Duodenal histology characteristic of coeliac disease does not necessarily negate a diagnosis of IBS. Did the IBS symptoms vanish on a gluten-free diet? In their table 1, Sanders and colleagues show data suggesting that 26% of ROME-II-positive patients have disorders other than IBS, but is that true? 6% were lost to follow-up, 5% had diverticular disease—surely not a cause of ROME II symptoms3—and many of the remaining disorders, such as infective enteritis, alcoholic diarrhoea, radiation enteritis, and IBS should have been clinically suspected by a careful doctor. How old were the patients with rectal carcinoma or colon
1346
polyps? Would they not have been picked up routinely on colon examination that the researchers say is normally done in patients older than 45 years and is recommended by ROME? Do the researchers think the polyps caused the IBS symptoms? Sanders and colleagues are correct to raise our sensitivity to coeliac disease, and their advocacy for early diagnosis is convincing. However, in addition to omission of clinical clues, there are two important issues that they do not discuss. IBS is the most common disorder seen in gastrointestinal clinics worldwide. What would be the cost of implementing their suggestion that a panel of immunological tests be part of an IBS work-up? Do they think that ROME III should add a negative result with such tests as a criterion for IBS? Perhaps the most important issue is the implication that recommendations for automatic testing could return us to the bad old days when IBS was deemed a diagnosis of exclusion. This attitude is damaging. No test or set of diagnostic criteria is infallible. Every patient deserves careful consideration of their complaints, and neither rote application of ROME II nor immunological tests for coeliac disease will serve. If they did, gastroenterologists could be replaced by computers and save a great deal of money—more than enough for the immunological tests. W Grant Thompson University of Ottawa, Ottawa, Ontario K2H 8C4, Canada 1
2
3
Sanders DS, Carter MJ, Hurlstone DP, et al. Association of adult coeliac disease with irritable bowel syndrome: a case-control study in patients fulfilling ROME II criteria referred to secondary care. Lancet 2001; 358: 1504–08. Thompson WG, Longstreth GF, Drossman DA, Heaton KW, Irvine EJ, Muller-Lissner SA. Functional bowel disorders and D functional abdominal pain. In: Drossman DA, Coraniari E, Talley NJ, Thompson WG, Whitehead WE, eds. The functional gastrointestinal disorders, 2nd edn. Washington: Degnon, 2000. Thompson WG, Patel DG. Clinical picture of diverticular disease of the colon. Clin Gastroenterol 1986; 16: 903–16.
Sir—One interpretation of the paper on the association between coeliac disease and IBS by David Sanders and colleagues1 is that there is a worrying 20–25% chance of missing organic disease with use of the ROME II criteria. This finding highlights the limitations of the these criteria as a dependable diagnostic tool. Furthermore, 14 of 300 patients turned out to have unsuspected coeliac disease. This number contrasts with two primary-care studies,2,3 in which no case of coeliac disease was
identified among 121 and 132 patients with IBS. In the study done by myself and other workers,3 we used Manning’s criteria to identify IBS, although the family physicians’ adherence to these were loose in several cases. Valori4 describes such cases as having odd symptoms that cannot be classified in neat diagnostic groups—a common difficulty in primary care. Patients referred to secondary care therefore differ from most of those who present in primary care. Sanders and colleagues’ cohort, for example, has a median age of 56 years with a sex ratio of 1:2·5. This ratio differs from the picture of IBS in primary care, in which Thompson5 noted an overwhelming 86% to be women (male to female ratio of 1:6), which is in keeping with most family physicians’ experiences. The surprising number of men (86 of 300 cases) in Sanders and colleagues’ study suggests that the selection of patients by the ROME II criteria does not reflect the general population prevalence of IBS and that the criteria do not help to distinguish with confidence patients with functional from those with organic disease. However, this study does highlight once again the emerging “look and you will find” picture of the coeliac iceberg that emerges via serological testing. Since serology is now cheap and accessible in primary care, family physicians probably should screen for coeliac disease patients with IBS who are being referred to secondary care, as Sanders and colleagues suggest. I suspect, however, that the detection rate will be far lower than that reported, since family physicians do not generally use the ROME II criteria for the diagnosis of this common disorder. Successful detection, after all, is knowing where to look. Harold Hin Hightown Surgery, Banbury, Oxford OX16 9DB, UK 1
2
3
4
5
Sanders DS, Carter MJ, Hurlstone DP, et al. Association of adult coeliac disease with irritable bowel syndrome: a case-control study in patients fulfilling ROME II criteria referred to secondary care. Lancet 2001; 358: 1504–08. Holt R, Darnley S, Kennedy T, Jones R. Screening for celiac disease in patients with clinical diagnosis of irritable bowel syndrome. Gastroenterology 2001; 120 (suppl 1): A757 (abstr 4064). Hin H, Bird AJ, Fisher P, Maby N, Jewell D. Coeliac disease in primary care: case finding study. BMJ 1999; 318: 164–67. Valori R. Coeliac disease in patients with irritable bowel syndrome. Lancet 2001; 358: 1475. Thompson WG, Heaton KW, Smyth GT, Smyth C. Irritable bowel syndrome in general practice: prevalence, characteristics and referral. Gut 2000; 46: 7882.
THE LANCET • Vol 359 • April 13, 2002 • www.thelancet.com
For personal use. Only reproduce with permission from The Lancet Publishing Group.