Irritable bowel syndrome (IBS) is a common chronic disorder that affects the large intestine. It has a prevalence of 10-20% in the western population with 12–14% of primary care visits being associated with IBS (El-Salhy, Hatlebakk, Gilja, & Hausken, 2014). In other words, the disorder is more common than diabetes, hypertension, or asthma making it a considerable bother for the international society (El-Salhy et al., 2014). Despite such high prevalence, only 30% of patients seek treatment for a variety of reasons (Lacy, 2003). The situation may be connected to cancer phobia, embracement about the symptoms, and disbelief ineffective treatment (Lacy, 2003). The symptoms of the disorder are inconsistent and may vary over time; therefore, the diagnosis of the condition is based on exclusion (El-Salhy et al., 2014). Patients with mild and moderate symptoms of the disorder are usually treated with lifestyle and diet alterations to improve their quality of life (El-Salhy et al., 2014). Patients with severe IBS symptoms are treated pharmacologically or with hypnotherapy (El-Salhy et al., 2014). The present paper offers a detailed overview and critical analysis of the proposed diagnoses and treatment methods of the disorder.
Diagnosis
Symptomatic Diagnosis
Even though the symptoms of the IBS are explicit, they are hardly distinguishable from other gastroenterological disorders. According to Holten, Wetherington, and Bankston, the most common symptoms of the condition are the change in appearance and frequency of stools and abdominal pain that is usually relieved by defecation. Additionally, the syndrome may be accompanied by mucus in stool, the feeling of incomplete evacuation, urgency, bloating, and distention. In other words, the symptoms of IBS mimic many other gastroenterological disorders including celiac disease, microscopic colitis, IBD, colorectal cancer, bile acid malabsorption, bacterial overgrowth, and pelvic floor disorders (El-Salhy et al., 2014). Since historically no biomarkers of the disorder are known, the symptomatic diagnosis is based on exclusion. However, this method appears to be a costly endeavor due to a large number of associated tests and procedures associated with the rejection of other possible diagnoses. Moreover, it takes several visits, which may cause patient dissatisfaction. Therefore, due to the large prevalence and inefficiency of the diagnostic procedures based on exclusion, there appears to be a need for a positive diagnosis of IBS.
To provide procedures for a positive diagnosis of IBS, there emerged criteria established by an international panel of experts. In 1988, Rome I criteria for a positive diagnosis of IBS emerged followed by revisions in 1999 (Rome II), and in 2006 (Rome III) (El-Salhy et al., 2014). According to Rome III criteria, IBS should be diagnosed in patients who have a history of abdominal pain or discomfort for at least 3 days in one month during three subsequent months. Additionally, the patient should have the signs of two symptoms from the following: improvement on defecation, change in stool frequency, or alteration of stool form. Moreover, the patients should not demonstrate loss of body weight, inflammation, fever, rectal bleeding, or anemia. The criteria aimed to avoid unnecessary tests, facilitate the choice of therapy, and improve the appreciation of the pathophysiology of IBS (El-Salhy et al., 2014). However, the criteria have been largely ignored by physicians due to the possibility of missing organic diseases that mimic IBS (El-Salhy et al., 2014). In summary, symptomatic diagnosis of IBS is problematic for multiple objective reasons.
Biomarkers
The impossibility of positive symptomatic diagnosis of IBS makes it clear that there is a need to establish biomarkers associated with IBS. Currently, patients with IBS undergo gastroscopy with duodenal biopsies and colonoscopy with segmental biopsies (El-Salhy et al., 2014). Recent studies show that IBS patients demonstrate gastrointestinal tract lesions involving gastrointestinal endocrine cells (El-Salhy et al., 2014). Namely, the reduction of duodenal cell density of chromogranin A can be used as a biomarker for a positive diagnosis of IBS. El-Salhy et al. (2014) state that large cohort studies confirmed good sensitivity and specificity of the proposed criterion. Additionally, the reduction of peptide YY cells in the rectum may be used as a biomarker to diagnose the disorder with sensitivity and specificity of 83% and 89% respectively (El-Salhy et al., 2014). In short, the diagnosis of IBS may become more efficient by the use of the biomarkers proposed above.
Critical Analysis
Critical appraisal of the literature revealed that there is inconsistency in opinions about the effectiveness of methods of IBS diagnosis. While Holten et al. recommend using Rome II criteria accompanied by other diagnostic tools, the article does not provide sufficient evidence for the effectiveness of the approach. The suggestions are made based on expertise rather than on empirical knowledge. Therefore, the results of the research did not provide enough evidence to support a particular diagnostic approach.
A more recent systematic review by El-Salhy et al. is different in findings in comparison with the study by Holten et al. First, El-Salhy et al. provide enough supportive evidence to claim that the Rome II criteria and its revision (Rome III) were underused by physicians due to the high probability of mistakes in diagnoses. Second, El-Salhy et al. underline the importance of biomarkers of IBS for the process of diagnosis supporting their claim with data from several studies. However. Even though the overviewed findings are promising, they are insufficient to promote the use of new diagnosis methods. Therefore, additional research is needed to find adequate approaches to a positive diagnosis of IBS.
Treatment
Non-Pharmacological Treatment
Non-pharmacological treatment may be effective for fighting the symptoms of the disorder and improving quality of life. According to El-Salhy et al., patients with mild and moderate symptoms of IBS usually benefit from diet alteration, reassurance, regular exercise, and probiotic intake. The treatment is closely associated with managing risk factors mentioned above, including reduction of stress, avoiding intolerable foods, and consuming increased amounts of fiber. At the same time, patients with severe symptoms usually benefit from hypnotherapy (El-Salhy et al., 2014). However, IBS-C does not respond well to the non-pharmacological treatment (El-Salhy et al., 2014). Therefore, physicians are to be aware of effective medications that can improve the conditions of their patients.
Pharmacological Treatment
Due to the shifts in understanding of the nature of IBS, there are emerged new drugs that help to fight the condition. Traditionally, IBS-C is recommended to be treated with tegaserod, while IBS-D is to be treated with alosetron (Lacy, 2003). However, due to the discovery of the connections between IBS and gastrointestinal tract lesions, another two medications for IBS-C have emerged. According to El-Salhy et al., the use of prucalopride, a prokinetic that is known to stimulate gut motility, has been associated with improved patient outcomes. El-Salhy et al. also promote the use of linaclotide, a guanylate cyclase-C agonist, for patients with IBS-C on an on-demand basis. Even though both of the medications are known to have no serious side effects, further studies are needed to confirm the effectiveness of both agents (El-Salhy et al., 2014). Due to the availability of a wide variety of treatment approaches, physicians are to be able to navigate their patients by choosing the most appropriate treatment.
Critical Analysis
The articles by El-Salhy et al. and Lacy were consistent about the non-pharmacological methods of IBS treatment, while there were differences in findings of the use of medications. Lacy provides sufficient evidence supporting the use of tegaserod and alosetron for treating IBS since the author overviews clinical trials with large cohorts. At the same time, the effectiveness of prucalopride and linaclotide use is not supported by empirical studies. Therefore, physicians should consider the use of medications with caution.
Conclusion
IBS is a considerable bother for the world population due to its high prevalence. The symptoms of the disorder include abdominal pain that is relieved by defecation, changes in evacuation frequency, and stool form alteration. Even though the sign of the condition is explicit, the diagnosis of the disorder is based on exclusion since the symptoms mimic other gastroenterological diseases. Recent research has shown that a positive diagnosis of the syndrome is possible by evaluating the changes in duodenal cell density of chromogranin A and reduction of peptide YY cells in the rectum. Additional evidence is required to recommend the use of biomarkers for a positive diagnosis of IBS. While most of the time IBS may be treated using non-pharmacological methods such as stress management, diet alteration, regular exercise, and hypnotherapy, some types of IBS may require the intake of medications. The recommended medications are tegaserod and alosetron, while prucalopride and linaclotide should be used with caution.
References
El-Salhy, M., Hatlebakk, J., Gilja, O., & Hausken, T. (2014). Irritable bowel syndrome: Recent developments in diagnosis, pathophysiology, and treatment. Expert Review of Gastroenterology & Hepatology, 8(4), 435-43. doi:10.1586/17474124.2014.888952
Holten, K. B., Wetherington, A., & Bankston, L. (2003). Diagnosing the patient with abdominal pain and altered bowel habits: is it irritable bowel syndrome? American Family Physician, 67(10), 2157-2164.
Lacy, B. (2003). Irritable bowel syndrome: New recommendations for diagnosis and treatment. Archives of Internal Medicine, 163(11), 1374-5.