Diagnosis and therapy of acute and chronic diarrhea

Many patients who present with acute or chronic diarrhea do not have an important organic disease. Most have functional diarrhea. The history, clinical examination, and initial laboratory studies should lead to a provisional diagnosis with respect to organic or functional origin and help define whether the disease affects the small or large intestine. Specific studies are then obtained to define organic causes. The most common causes of acute diarrhea are infections and drugs, while the most common causes of chronic diarrhea are inflammatory bowel disease, malabsorption, parasitic infections, carcinoma of the large bowel, and metabolic diseases. Clinicians should remember that patients with functional diarrhea are as prone to other severe disease as the rest of the population and avoid allowing the functional problem to mask other signs.     

Management of irritable bowel syndrome

Irritable bowel syndrome is the most common functional disorder of the gastrointestinal tract and is frequently treated by family physicians. Despite patients' worries about the symptoms of irritable bowel syndrome, it is a benign condition. The diagnosis should be made using standard criteria after red flags that may signify organic disease have been ruled out. An effective physician-patient relationship is vital to successful management. Episodes of diarrhea are best managed with loperamide, while constipation often will respond to fiber supplements. Antispasmodics or anticholinergic agents may help relieve the abdominal pain of irritable bowel syndrome. Refractory cases are often treated with tricyclic antidepressants. Newer agents such as tegaserod and ondansetron target neurotransmitter receptors in the gastrointestinal tract Some forms of psychologic treatment may be helpful, and gastroenterology consultation is occasionally needed to reassure the patient. Comorbid conditions such as depression or anxiety should be investigated and treated.     

Infectious diarrhea.

Infectious diarrhea is an extremely common illness that affects millions of Americans annually. For most patients, the illness is a self-limited one. Its major risk is dehydration. However, for some patients, diarrhea can lead to severe dehydration or be associated with bacteremia and metastatic infection. Patients with these conditions require prompt treatment. A large number of organisms have been associated with diarrhea in humans, and most laboratories routinely screen for Salmonella, Shigella, and Campylobacter. Other bacteria, parasites, and viruses account for a significant percentage of diarrhea cases and frequently go undetected. This article summarizes many of these pathogens and describes the settings in which they can be acquired. Food distribution networks have made the delivery of previously rare foods to remote areas a commonplace occurrence; this has also led to new challenges in the diagnosis and prevention of food-borne illnesses. Outbreaks of diarrhea now frequently extend across many states. The identification of a rare strain of a bacterial pathogen or changes in the isolation rate of common pathogens may be early clues to the cause of such an ongoing outbreak. Most enteric pathogens cause disease by either stimulating the secretion of fluids at the level of the small bowel or by irritating and invading the colon. Organisms that cause disease by the latter mechanism have the potential to invade the blood stream and spread to other parts of the body, including the bones and the central nervous system. Several organisms have been associated with specific postinfectious syndromes that are responsible for additional morbidity and mortality. The antibiotic resistance of bacterial pathogens has been increasing, and this has a limiting effect on the empiric treatment choices available for suspected bacterial diarrhea. Careful attention to local sensitivity patterns and appropriate testing of the patient's isolate are among the important factors that lead to successful treatment decisions.     

Diagnosis and Management of IBS in Adults

Irritable bowel syndrome is defined as abdominal discomfort or pain associated with altered bowel habits for at least three days per month in the previous three months, with the absence of organic disease. In North America, the prevalence of irritable bowel syndrome is 5 to 10 percent with peak prevalence from 20 to 39 years of age. Abdominal pain is the most common symptom and often is described as a cramping sensation. The absence of abdominal pain essentially excludes irritable bowel syndrome. Other common symptoms include diarrhea, constipation, or alternating diarrhea and constipation. The goals of treatment are symptom relief and improved quality of life. Exercise, antibiotics, antispasmodics, peppermint oil, and probiotics appear to improve symptoms. Over-the-counter laxatives and antidiarrheals may improve stool frequency but not pain. Treatment with antidepressants and psychological therapies are also effective for improving symptoms compared with usual care. Lubiprostone is effective for the treatment of constipation-predominant irritable bowel syndrome, and alosetron (restrictions for use apply in the United States) and tegaserod (available only for emergency use in the United States) are approved for patients with severe symptoms in whom conventional therapy has been ineffective.     

A possible indicator of functional pain: poor pain scale correlation.

We studied correlations of pain measures in patients with either inflammatory bowel disease (IBD), a disease with a clear organic cause, or irritable bowel syndrome (IBS), a functional pain syndrome in which there is little demonstrable pathology. Correlations were determined between measures on the visual analogue scale (VAS) and on the McGill Pain Questionnaire (MPQ). The VAS score and present pain intensity scale (PPI) of the MPQ correlated well in the organic IBD but correlated poorly in the functional IBS. Differences in correlation between the VAS and PPI scores in functional versus organic disease did not appear to be due to altered sensory and affective pain components. This finding is similar to what we observed in our previous study of organic and functional pain syndromes in the musculoskeletal system. Correlations between the other measures are also discussed.     

Diagnosing the patient with abdominal pain and altered bowel habits: is it irritable bowel syndrome?

Diagnosing a patient who presents with abdominal pain and altered bowel habits can be challenging. Although serious organic illnesses can cause these symptoms, irritable bowel syndrome is commonly responsible. It can be difficult to properly evaluate these patients without overusing diagnostic tests and consultation. A practical approach for diagnosing irritable bowel syndrome is suggested, using the Rome II criteria and the presence of alarm symptoms such as weight loss, gastrointestinal bleeding, anemia, fever, or frequent nocturnal symptoms as starting points. If there are no alarm symptoms and the Rome II criteria are not met, it is acceptable to reevaluate the patient at a later date. If there are no alarm symptoms and the Rome II criteria are met, the patient should be categorized on the basis of age: patients 50 years or younger can be evaluated on the basis of predominant symptoms--constipation, diarrhea, or abdominal pain. Patients older than 50 years should be fully evaluated and considered for gastroenterology referral. If alarm symptoms are present, a full evaluation should be performed (and gastroenterology referral considered), regardless of the patient's age.     

Acute undifferentiated human diarrhea in the tropics: I. Alterations in intestinal microflora

The microflora of the small and large intestine was determined in 17 adults with acute undifferentiated diarrhea in Calcutta, India. On the basis of bacteriologic findings, the patients could be divided into two groups: those with a predominant flora of Escherichia coli (eight patients) and those with a mixed coliform flora (nine patients). In the former group, E. coli were distributed throughout the small and large bowel. Broth filtrates of these isolates contained an enterotoxin which caused fluid accumulation in the rabbit intestinal loop model. Toxigenic E. coli were cleared rapidly from the small bowel during the acute period; some patients only had the "hot" strains in their fecal effluent. During convalescence, the serotypes of E. coli changed and the new strains did not elaborate enterotoxin. Only one of the eight patients had a serotype previously associated with diarrhea. Acute undifferentiated diarrhea in the remaining cases was apparently caused by untypable E. coli or by typable strains not generally considered pathogenic.Small bowel and fecal cultures from the mixed flora group revealed a heterogeneous mixture of Gram-negative enteric bacilli and a distinct pattern could not be discerned. Further study will be needed to elucidate the cause of diarrhea in these cases.     

Evaluation of chronic diarrhea

Chronic diarrhea, defined as a decrease in stool consistency for more than four weeks, is a common but challenging clinical scenario. It can be divided into three basic categories: watery, fatty (malabsorption), and inflammatory. Watery diarrhea may be subdivided into osmotic, secretory, and functional types. Watery diarrhea includes irritable bowel syndrome, which is the most common cause of functional diarrhea. Another example of watery diarrhea is microscopic colitis, which is a secretory diarrhea affecting older persons. Laxative-induced diarrhea is often osmotic. Malabsorptive diarrhea is characterized by excess gas, steatorrhea, or weight loss; giardiasis is a classic infectious example. Celiac disease (gluten-sensitive enteropathy) is also malabsorptive, and typically results in weight loss and iron deficiency anemia. Inflammatory diarrhea, such as ulcerative colitis or Crohn disease, is characterized by blood and pus in the stool and an elevated fecal calprotectin level. Invasive bacteria and parasites also produce inflammation. Infections caused by Clostridium difficile subsequent to antibiotic use have become increasingly common and virulent. Not all chronic diarrhea is strictly watery, malabsorptive, or inflammatory, because some categories overlap. Still, the most practical diagnostic approach is to attempt to categorize the diarrhea by type before testing and treating. This narrows the list of diagnostic possibilities and reduces unnecessary testing. Empiric therapy is justified when a specific diagnosis is strongly suspected and follow-up is available.     

Primary sclerosing cholangitis: a case presentation.

Liver function tests are elevated in a variety of settings and with a mild elevation, it is difficult to decipher the cause. Typical causes of elevated liver enzymes may range from hepatocellular injury such as hepatitis C, to obstructive causes, such as primary sclerosing cholangitis. Primary sclerosing cholangitis is known to be associated with inflammatory bowel disease and may be more common than once thought.This article presents case study of a patient who presented with mildly elevated liver function tests and intermittent diarrhea. The patient was diagnosed with Crohn's disease and primary sclerosing cholangitis. The patient's presentation and the relation of inflammatory bowel disease and primary sclerosing cholangitis will be discussed. The importance of early detection of primary sclerosing cholangitis in an effort to decrease the morbidity and mortality from cholangiocarcinoma will also be emphasized. An overview of various diagnostic testing needed to make the diagnosis, as well as treatment modalities of both Crohn's disease and primary sclerosing cholangitis will also be presented.     

Video wireless capsule endoscopy: a diagnostic tool for early Crohn's disease.

Crohn's disease is a chronic immune-mediated disease that affects any or all segments of the gastrointestinal tract, but is mainly found in the small intestines or colon. Crohn's disease in the early stages present with symptoms such as chronic diarrhea, abdominal pain, and weight loss that may mimic other conditions and cause a delay in diagnosis. Many patients experience emotional difficulties related to this debilitating disease. Current procedures used to visualize the small bowel for diagnosis of Crohn's disease include small-bowel follow through, enteroclysis, and computerized tomography, but do not provide definition of the mucosal surface. Clinical research shows us the diagnostic yield of these tests are not as high as once thought. A new diagnostic tool, the M2A Video Capsule, can be used to visualize the small bowel mucosa. With the detailed photo images provided by the capsule, the physician now has the ability to detect subtle changes in the mucosal lining that may be consistent with early Crohn's disease that were previously not available or identifiable. Earlier disease treatment and management may decrease the inflammatory changes that lead to bowel thickening and stricturing and have a positive impact on the patient's total quality of life.     

Dietary treatment in patients with irritable bowel syndrome]

The author claims that dietary treatment of irritable bowel syndrome (IBS) consists of methods aiming at improvement of abdominal symptoms and functional disorder of the bowel. Patients with constipation are recommended to take dietary fiber positively, while those with diarrhea should consume sparingly food which may cool their body. Both should avoid overeating and overdrinking, and have regular dietary habits. In order to improve the functional disorder of the bowel, it is necessary for those patients (1) to be careful not to take often refined cereals or manufactured foods, (2) to eat green and yellow vegetables and seaweeds positively, as well as, protein and fat in proper quantity, and (3) to take care of the well-balanced intake of various kinds of vitamins, minerals and other nutriments.     

Bloody diarrhea in children

Bloody diarrhea is a common problem in children. It is important to distinguish bloody diarrhea from other causes of rectal bleeding. Bacterial infections and parasitic infestations are responsible for most of the cases. Milk allergy is a frequent cause in young infants. Chronic inflammatory bowel disease occurs in older children. The cause is most often apparent after a thorough history and physical assessment is performed and the stool is examined for pathogens. Proctosigmoidoscopy with biopsy is the procedure of choice if the stool tests for pathogens are negative. A few children require further diagnostic evaluation by colonoscopy and/or radiographic procedures.     

Gastrointestinal insights during the COVID-19 epidemic

Coronavirus disease-2019 (COVID-19) has so far caused hundreds of mortalities worldwide. Although respiratory symptoms are the main complication in COVID-19 patients, the disease is also associated with gastrointestinal problems, with diarrhea, nausea, and vomiting being primary COVID-19 symptoms. Thus, cancer and inflammatory bowel disease (IBD) management, stool viral tests, and virus exposure are major concerns in the context of COVID-19 epidemic. In patients with colorectal cancer and IBD, the colonic mucosa exhibits elevated angiotensin-converting enzyme 2 receptor levels, enhancing COVID-19 susceptibility. In some cases, positive viral stool tests may be the only indicator of infection at admission or after leaving quarantine. Without supplemental stool tests, the risk of undetected COVID-19 transmission is high. Moreover, viral exposure during the regular or emergency endoscopic examination should be avoided. We carefully discuss key gastrointestinal concerns with regard to COVID-19 and call for more attention to such problems.     

Inflammatory bowel disease and irritable bowel syndrome

The irritable bowel syndrome accounts for 30 to 50 per cent of patients cared for by gastroenterology practices. Irritable bowel syndrome is more common than inflammatory bowel disease. Therefore, it should not be surprising that some patients with inflammatory bowel disease are initially told that they have irritable bowel syndrome before a diagnosis of inflammatory bowel disease is firmly established. This article contends that many people have both irritable bowel syndrome and inflammatory bowel disease.     

Mast Cells and Headache in Crohn's Disease

SYNOPSIS
Four patients with vascular headaches of remarkable severity and chronicity not responding to usual therapies brought attention to their families in which at least two members each also have Crohn's disease. Hitherto an association of Crohn's disease with vascular headache of the migrainous type has not been recognized.One patient suffered bouts of extreme constipation at age four years. When eight years old he developed "screaming, pounding headaches". During headaches, intermittent crampy periumbilical pain and diarrhea appeared. Subsequent radiologic and surgical evidence resulted in a diagnosis of Crohn's disease. His 11-year-old brother was seen for headaches which were intractable over a period of at least six months, but bowel symptoms has not appeared as yet. Their father has Crohn's disease.A 19-year-old woman with Crohn's disease presented with headaches of the migrainous type of eight months duration, resistent to all therapies. Her mother has Crohn's disease and migraine and a sister has peptic ulcers, "gaseous colon" and migraine.Resected bowel of three of these patients showed large numbers of mast cells. We suggest that vasoactive substances, including histamine released from mast cells, could cause headache. Moreover, impaired sulfate conjugation of monamines, or decreased monoamine oxidase in diseased bowel could facilitate the absorption and increase the circulation of vasoactive substances causing headache.     

The spectrum of hepatic dysfunction in inflammatory bowel disease.

The spectrum and incidence of liver disease is described among a large series of patients with inflammatory bowel disease. The incidence of significant liver disease identified by the presence of serial biochemical abnormalities of liver function was 8.2 per cent. Transient peri-operative changes in liver function tests are common and usually relate to underlying intra-abdominal sepsis. Percholangitis, sometimes termed portal triaditis, is one of the commoner lesions, and is usually associated with extensive colitis and improves with resection of the underlying bowel disease. Cirrhosis of the liver is an important but uncommon complication and is usually associated with extensive long-standing disease. Stenosing cholangitis and biliary tract carcinoma are both important though rare associations. They are both associated with extensive disease of long-standing, but resection of the underlying inflammatory bowel disease does not necessarily protect the individual from these complications. Although stenosing cholangitis is a diffuse lesion of the biliary tree it is important to exclude strictures of the extra-hepatic biliary tree which may be amenable to surgical correction. Hepatic dysfunction is rarely the sole indication for advising surgery for the underlying bowel disease but the identification of the nature of the hepati- dysfunction provides a rational basis for such a decision and opportunities for the surgical correction of the hepatic lesion itself.     

Bile acids in radiation-induced diarrhea

Radiation-induced bowel disease manifested by debilitating diarrhea is an unfortunate consequence of therapeutic irradiation for pelvic malignancies. Although the mechanism for this diarrhea is not well understood, many believe it is the result of damage to small bowel mucosa and subsequent bile acid malabsorption. Excess amounts of bile acids, especially the dihydroxy components, are known to induce water and electrolyte secretion and increase bowel motility. We have directly measured individual and total bile acids in the stool samples of 11 patients with radiation-induced diarrhea and have found bile acids elevated two to six times normal in eight of them. Our patients with diarrhea and increased bile acids in their stools had prompt improvement when given cholestyramine. They had fewer stools and returned to a more normal life-style.