In patients suffering from reflux, is it reasonable to make a complete assessment of esophageal motility ?

E Ancona, G Zaninotto, M Costantini (Padova)

The diagnosis of the gastroesophageal reflux disease is still an intriguing problem for the physician. This is due to the fact that both a symptomatic and endoscopic definition of the disease are not completely satisfactory.

Symptoms considered indicative for a gastroesophageal reflux such as heartburn or acid regurgitation are very common : Nebel and Tibbling reporting a prevalence of 5-7 p. cent in the population [1-2]. These symptoms are not absolutely specific in absence of esophagitis, since they can be caused by other disease such as cholelitiasis, peptic ulcer of the stomach or of the duodenum, gastritis, esophageal carcinoma. Moreover, the prevalent symptom in patients suffering from a gastroesophageal reflux disease can mimic other diseases such as respiratory or cardiovascular disorders.

An endoscopic definition of the disease is also unsatisfactory, because if we accept a definition of the disease based on the presence of esophagitis at endoscopy, we accept that all types esophagitis are caused by excessive regurgitation of gastric juice: data indicate that this is true in 90 p. cent of the cases, but in 10 p. cent esophagitis is caused by other etiology, the most common being an unrecognized chemical injury from drug ingestion [3, 4].

Moreover, an endoscopic-based diagnosis leaves those reflux patients who have not developed a mucosal lesion, undiagnosed. Data indicate that it occurs in approximately 40 p. cent of the patients with typical symptoms and proven GERD [3, 5]. An esophageal biopsy is of little help since the sensitivity and specificity of an epithelial biopsy in absence of esophagitis is 0.75 and 0.9, respectively and largely depends on an interest the pathologist shows for proper reading [6]. Last but not least, this definition characterizes the GERD on the basis of a complication of the disease itself and in our opinion this is not a workable solution.

Since the basic abnormality of the GERD is an abnormal exposure of the esophagus to the refluxed acid gastro-intestinal juice due to an incompetent Lower Esophageal Sphincter, a reasonable approach to the diagnosis of this disease is to assess these conditions by means of prolonged 24-hour pH monitoring and esophageal manometry. The first test has been widely accepted as the most sensible and specific test in the GERD diagnosis [7, 8] and it can be performed on a outpatient basis lowering the health cost and allowing the patient a normal behaviour during the test. This test assumes that changes in esophageal pH below a certain level (pH 4) are due to the reflux of acid contents, provided that acid food or drink has been excluded from the patient's diet.

Occasional regurgitation of acid contents into the esophagus occurs in healthy individuals, especially during the post-prandial period, as demonstrated by the 24-hour pH monitoring. Six parameters, as proposed by Johnson and DeMeester [9], are used to evaluate the acid exposure in the distal esophagus : the percent of total time below pH 4, the percent of time below pH 4 while the patient is in upright position, the percent time below pH 4 while the patient is in supine position, the total number of the episodes of reflux, the number of reflux episodes lasting 5 minutes or more, the duration of the longest episode of reflux: we consider a test abnormal whenever 2 or more of these parameters exceed the mean and two standard deviation of the value found in a normal population.

A limit of this test is the necessity of having one's own control group in each esophageal lab: in fact, small, but significative differences have been observed between Italian and American healthy volunteers in the exposition of the distal

Table I. Gastroesophageal reflux in Italian healthy volunteers and comparison with the value obtained by Johnson & DeMeester (1974) in healthy American volunteers.

		TOT	UP	SUP	GER	GER	max
		%	%	%	n	> 5 mn	GER (mn)
	American
	volunteers
	(n = 15)
	Mean	1.47	2.33	0.286	20.6	0.60	3.866
	SD	1.38	1.97	0.467	14.77	1.24	2.689
	Italian
	volunteers
	(n= 15)
	Mean	1.68	2.68	0.813	25.46	0.571	4.595
	SD	1.45	3.18	1.09	17.37	1.049	3.099

TOT = total time of acid exposure, UP = upright time, SUP = supine time, GER n = total number of reflux episodes, max GER = duration of the longest episode.

esophagus to the acidic gastric juice (table I) [10, 11], probably due to differences in life and dietary habits.

The esophageal manometry allows us to measure the characteristics of the Lower Esophageal Sphincter (i.e. the resting tone, the overall length and the length of the sphincter exposed to the abdominal pressure) and the esophageal body peristalsis. Esophageal manometry reveals abnormalities of the LES (a pressure lower than 6 mmHg, an overall length less than 2 cm and an abdominal length less than 1 cm) in 60 p. cent of patients with proven gastroesophageal reflux [12], thus the test has not a high sensitivity, but it correctly identifies those patients who will show a failure or recurrence of the same symptoms after medical therapy and in whom a surgical treatment should be recommended to improve LES competency [13].

Moreover, the assessment of esophageal motility by means of esophageal manometry is useful in evaluating an underlying motor disorder such as the absence of motility observed in scleroderma patients [14], or the failure of peristalsis occasionally observed in patients with severe esophagitis and stricture [15], thus allowing the surgeon to choose the appropriate antireflux operation. The functional tests are mandatory whenever a recurrence of reflux is observed because of a failure of the previous repair [16].

A practical approach, following these principles, is represented by the flow-chart we use in symptomatic patients (figure 1). Patients with typical symptoms and esophagitis endoscopically detected are presumed to have a gastroesophageal reflux disease and must be treated with H2 blockers for six months: in case of failure of the therapy (worsened or not improved symptoms or esophagitis) or recurrence after the therapy is suspended, patients are studied with functional tests.

In those patients with atypical symptoms and in patients with symptoms but without esophagitis, esophageal functional tests should be performed before starting any medical treatment.

Figure 1. Gastroesophageal reflux disease : diagnostic Flow-Chart.

References

1. Nebel OT, Foznes MF, Castell DO (1976) Symptomatic gastroesophageal reflux: incidence and precipitating factor. Dig Dis Sci 21 : 955-959.

2. Tibbling L (1982) Esophageal dysfunction and angina pectoris in a Swedish population selected at random. Acta Med Scand 209 (suppl 644) 71-74.

3. DeMeester TR, Wang CL, Wernly JA et al. (1980) Technique indications and clinical use of 24-hour esophageal pH monitoring. J Thorac Cardiovasc Surg, 79: 656-667.

4. Bonavina L, Evanders A, DeMeester TR et al. (1987) Drug induced esophageal strictures. Ann Surg, 206: 173-183.

5. Zaninotto G, Costantini M, Bonavina L et al. (1987) Manometric characteristics of the distal esophageal sphincter and patterns of gastro-esophageal reflux in healthy volunteers and patients Eur Surg Res, 19: 217-224.

6. DeMeester TR, Johnson LF (1976) The evaluation of objective measurements of gastroesophageal reflux and their contribution to patient management Surg Clin North Am, 56: 39-53.

7. Fuchs KH, DeMeester TR, Albertucci M (1987) Specificity and sensitivity of objective diagnosis of gastroesophageal reflux disease. Surgery, 702 : 575-580.

8. Pujol A, Grande L, Ros E, Pera Cristobal (1988) Utility of 24-hour intraesophageal pH monitoring in diagnosis of gastroesophageal reflux. Dig Dis Sci 33 : 1134-1140.

9. Johnson LF, DeMeester TR (1974) Twenty-four hour pH monitoring of the distal esophagus : a quantitative measure of gastroesophageal reflux. Am J Gastroenterol 62 : 325-332.

10. Zaninotto G, Merigliano S, Baessato M et al. (1984) Gastroesophageal reflux in Italian healthy volunteers and patients : relationship between gastro-esophageal reflux, endoscopic esophagitis and symptoms. Dig Surg 1 : 211-216.

11. Mattioli S, Pilotti V, Spangaro M et al. (1989) Reliability of 24-hour home esophageal pH monitoring in diagnosis of gastroesophageal reflux. Dig Dis Sci 34 : 71-78.

12. Zaninotto G, DeMeester TR, Schwizer W et al. (1988) The lower esophageal sphincter in health and disease Am J Surg 155 : 104-111.

13. Lieberman DA, Keefe EB (1986) Treatment of severe reflux esophagitis with cimetidine and metoclopramide. Ann Int Med 104: 21-26.

14. Zaninotto G, Peserico A, Costantini M et al. (1989) Esophageal motility and lower esophageal sphincter competence in progressive systemic sclerosis and localized scleroderma. Scand J Gastroenterol 24: 95-102.

15. Zaninotto G, DeMeester TR, Bremner CG et al. (1989) Esophageal function in patients with reflux induced strictures and its relevance to surgical treatment. Ann Thor Surg 47 : 362-370.

16. Ancona E, Zaninotto G, Costantini M et al. (1987) Reoperation after complication or failure of antireflux surgery. In Diseases of the Esophagus : JR Siewert, AH Holscher Eds, Springer Verlag New York, pp 1251-1254.