A MICROSCOPIC VIEW OF THIS CHAPTER
• Diarrhea can be acute or chronic.
• Acute diarrhea is caused by an infection of bad microbes.
• Probiotics prevent the ability of bad microbes to infect the intestinal tract.
• Certain probiotics reduce the severity and duration of diarrhea.
• By improving immunity in the intestinal tract, probiotics can prevent diarrhea.
• Antibiotic use destroys probiotics and increases the risk of diarrhea.
• Probiotics can be used at the same time as antibiotics.
No matter whether you call it a lavatory, the ladies’ room or the porcelain throne, no one enjoys being uncomfortable on the toilet. Diarrhea and constipation are among the top complaints about the digestive tract. Do you suffer from these toilet woes?
Diarrhea can be the most dangerous health problem of these two intestinal issues. One hundred million people are affected with acute diarrhea each year in the United States. Perhaps this explains why there are so many jokes about the toilet in Western society. Unfortunately, diarrhea is no joking matter—particularly, when you realize that of the one hundred million affected with diarrhea each year about three thousand people die from it. Diarrhea is not just a major health problem in North America; it is a global issue. A large proportion of the world’s population, even in developed countries, is affected by foodborne diarrhea. Sadly, a majority of the deaths globally occur among children in the developing world. People of all ages can get diarrhea. In the United States, each child will have had seven to 15 episodes of diarrhea by age five, and the average adult is afflicted with acute diarrhea four times a year.
The average adult has a bout of acute diarrhea about four times a year.
WHAT IS DIARRHEA ?
Diarrhea is loose, watery stools. Typically, a person with diarrhea will pass stool more than three times a day. Acute (short-term) diarrhea is very common and usually goes away without any medical help in one to two days. Diarrhea may be accompanied by cramping, abdominal pain, bloating, nausea and/or an urgent need to use the bathroom. Depending on the cause, a person may have a fever or bloody stools.
Can Diarrhea Kill?
Diarrhea caused by a bad microbe (bacteria, virus or parasite) can result in death. The bad microbe can sufficiently damage the intestines to cause severe diarrhea, dehydration and drastically reduce nutrient absorption to a point where the body cannot get enough vital nutrients and water to survive. This is not common; however, if diarrhea is left untreated or if the pathogenic species is unresponsive to treatment, death can occur.
Generally, there are four types of diarrhea: acute diarrhea, traveler’s diarrhea, antibiotic-associated diarrhea and chronic diarrhea.
Acute Diarrhea
Acute diarrhea is a term used to describe a short period of loose stools. The cause can vary from foreign microbe or parasite ingestion, consumption of spoiled foods, use of antibiotics or infection by a virus.
Traveler’s Diarrhea
Traveler’s diarrhea is a common term used to describe acute diarrhea in a person who has consumed water or food contaminated with bacteria, viruses or parasites when visiting a foreign location. This is not common in Canada, the United States, Australia, New Zealand or most European countries.
Antibiotic-Associated Diarrhea
Antibiotic-associated diarrhea is a type of acute diarrhea. Antibiotics are very effective at eliminating bacteria from the body. They are helpful if there is an overgrowth of bad (pathogenic) bacteria that causes illness such as Strep throat or a urinary tract infection. However, antibiotics are not selective about which bacteria they clean out of the body. Probiotics are also destroyed with antibiotic use. After antibiotic use, the body is more susceptible to infection by bad microbes because there is a low level of probiotics which normally defend the body from invasion. Diarrhea caused by bad microbes after antibiotic use is called antibiotic-associated diarrhea. This can be a serious problem in the elderly and children.
Chronic Diarrhea
Chronic diarrhea may be a sign of a more serious problem. Chronic diarrhea is usually related to a functional problem in the intestines such as irritable bowel syndrome or inflammatory bowel disease. Chronic diarrhea poses the risk of dehydration, the very risk that puts the elderly and children at risk of death. Dehydration is a condition in which the body lacks enough fluid to function properly. To avoid serious health problems, dehydration should be treated quickly. All individuals suffering from diarrhea should focus on rehydrating the body.
WHAT CAUSES DIARRHEA ?
There are many things that can cause diarrhea. Appendix 6-1 provides a list of potential causes of diarrhea. Acute diarrhea is usually due to a bacteria, virus or parasite infection. When a bacteria, virus or parasite is able to flourish in the intestines, it causes damage to the intestinal cells. How do they cause damage? Bad microbes produce toxic chemicals, which they release into the intestines. These toxins cause damage to the cells that line the intestines. The result is swelling or inflammation of the intestinal walls and diarrhea. These toxins damage the microvilli of the small intestines. The microvilli are finger-like projections that absorb nutrients. The longer the villi are, the more surface area there is for absorption of nutrients from you gut into your bloodstream. In other words, long villi are key to a healthy body. Damage to intestinal cells (including those which make up the villi) by bacteria, viruses or parasites reduces the body’s ability to absorb nutrients and water. The result is faulty water absorption, which causes diarrhea and dehydration.
Diarrhea is responsible for several million deaths around the globe each year. It is a major world health problem. It is thought that predisposition to infections (e.g., diarrhea) is associated with immaturity and improper functioning of the intestinal barrier. In other words, the lining of the intestine is unable to keep bad microbes away from the intestinal cells. Probiotics help promote a healthy, strong intestinal barrier. As such, the use of probiotics can help to prevent and treat diarrhea. Bifidobacteria and other lactic acid bacteria have been shown in research trials around the globe to protect the body against the devastating effects of diarrhea.
ACUTE DIARRHEA IN CHILDREN
Probiotics can help stop diarrhea in children. This is not news. We’ve read about it in the newspaper for over a decade. The most well-known effect of consuming probiotics is their ability to reduce the severity and duration of diarrhea in children. Early studies were done in Asia with heartwarming results. Resolving acute diarrhea in children is of great importance in third-world countries where infants commonly drink bacteria-, virus- and parasite-contaminated water, which leads to diarrhea and even death.
Acute infantile diarrhea is often the result of an infection by the Rotavirus. Children with a Rotavirus infection have fever, nausea and vomiting, which are often followed by abdominal cramps and frequent, watery diarrhea. Children who are infected may also have a cough and runny nose; however, as with all viruses, all or few of these symptoms may appear.
Rotavirus is particularly common in the winter. In North America and other countries with a temperate climate, Rotavirus has a winter seasonal pattern, with annual epidemics occurring from November to April.
Rotavirus most often infects infants and children, aged three months to two years.
Since Rotavirus is stable in the environment, it can easily be transferred from person to person. It is typically transferred by fecal-oral transmission. Rotavirus moves from one human to another by ingestion of contaminated water or food and contact with contaminated surfaces. All it takes is one person forgetting to wash his or her hands after going to the washroom and then proceeding to prepare a salad for dinner.
Many research studies have investigated which probiotic species can prevent and treat acute diarrhea in children. Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium lactis, Lactobacillus rhamnosus and Lactobacillus reuteri are known to have positive health benefits in children who are infected with Rotavirus. Appendix 6-2 summarizes the clinical evidence on the ability of probiotic strains to fight diarrhea in children and infants. Let’s look at some of this research in more detail.
As diarrhea can be so devastating, an obvious population group to target in studies is children hospitalized with diarrhea. Here are the particulars on two such research studies that involved children suffering from diarrhea.
Studies of Probiotics for Treatment and Prevention of Diarrhea in Children
In a clinical trial, 69 children who were hospitalized for acute diarrhea in Denmark were randomized to receive either a 10 million CFU mixture of Lactobacillus rhamnosus and Lactobacillus reuteri or placebo , twice daily for five days. Both of these strains have been shown to have probiotic characteristics in in vitro (test tube studies) and in healthy adults. The combination of L. rhamnosus and L. reuteri resulted in a 48% reduction in the hospitalization rate and effectively reduced diarrhea in the children. We know that probiotics can help fight diarrhea in healthy adults and in infected children.
This second study offers a measure of how much probiotics help alleviate diarrhea in children. In two hospitals, a prospective, randomized, placebo-controlled trial was conducted. The trial involved children between the age of six and 36 months with Rotavirus-associated diarrhea. The children were randomized into three groups and received either placebo or 10 billion or 10 million CFUs of
L. reuteri once a day for up to five days. The duration of watery diarrhea was greatly reduced in those receiving the
L. reuteri supplementation. The large dose (10 billion CFU) had a more profound effect on shortening the duration of watery diarrhea than the smaller dosage. In fact, only 48% of the children receiving the higher dosage of probiotics had watery diarrhea by the second day of treatment, versus 70% of those receiving the small dosage and 80% of those in the placebo group. This study tells us two things:
1. L. reuteri appears to shorten the duration and severity of Rotavirus-associated diarrhea in children as young as six months of age.
2. The effectiveness of probiotics depends on the dosage.
Please note that all of the research to date suggests that probiotics have the best effects on your health when you consume dosages of at least 10 million to 10 billion (107 to109) CFUs.
Probiotics do not just help children fight off a Rotavirus infection; they may also offer a preventative effect. L. casei was shown in a multicenter research trial in France in 2000 to effectively reduce acute diarrhea incidence in children. In another trial, both Bifidobacterium bifidum and Streptococcus thermophilus were given in a milk formula to infants and was found to reduce the number of times the children got sick with a Rotavirus infection. Bifidobacterium breve has also shown the ability to prevent infections of Rotavirus in children. As we can see, there are many studies showing that probiotics, when taken regularly, can help prevent children from getting sick with Rotavirus infections.
Can Probiotics Help Children in a Daycare Setting?
In 2002, a group of Danish researchers decided to look into the ability of probiotics to help children with acute diarrhea attending daycare centers. The children were supplemented with 10 million (107) CFUs of L. rhamnosus and L. reuteri twice daily for five days. The children taking the probiotic recovered twice as fast as those receiving the placebo. Thus, the researchers concluded that a combination of L. rhamnosus and L. reuteri is effective at shortening the duration of acute diarrhea in daycare children. It would appear, based on all of these studies, that probiotics can help prevent children from getting diarrhea, even in high-risk locations like daycare centers and help them feel better, faster when they do become ill with diarrhea.
Is One Probiotic Species Better Than Another?
Few studies have directly focused on whether one species is better than another in treating acute diarrhea in children. One study compared a Lactobacilli strain to a Bifidobacteria strain. L. reuteri was compared to B. lactis and to a placebo in a prevention study in childcare centers in Israel. L. reuteri was effective at reducing the severity of the children’s diarrhea. It was more effective than B. lactis. As Lactobacilli species love to live in the small intestine, the location of the diarrhea infection, it is likely that these species would be most effective in treating diarrhea.
Is there one species of Lactobacilli that is better at preventing diarrhea than others? L. rhamnosus strain GG (also called L. casei) was compared with L. rhamnosus Lactophilus. Lactobacillus rhamnosus GG was more effective in reducing the quantity of watery stools after the first day of treatment, while L. rhamnosus Lactophilus was not. These observations suggest that different species of Lactobacilli have different abilities to treat diarrhea. Unfortunately, we do not yet know which probiotic is best at treating diarrhea. Further studies are needed.
The Role of Yogurt
What about using yogurt as a treatment for acute diarrhea in children? The literature is split: some studies suggest yogurt is helpful and some do not. However, there tends to be a trend in the research that yogurt can shorten the duration of diarrhea in children.
Yogurt may offer some benefit in acute diarrhea in children.
Lactobacilli are used as starter organisms to make yogurt; thus it is not surprising to think of yogurt as a treatment for diarrhea. On the other hand, children can have undetected food intolerances and allergies to dairy products. Giving yogurt to these children to treat diarrhea may make the problem worse. Using yogurt to help alleviate acute diarrhea in children should be reserved for those known to be toleratant to dairy products.
There are many more clinical studies that have investigated the effect of probiotics on children with acute diarrhea. In fact, it could almost be a book in itself. Appendix 6-2 offers a summary of these studies. We can conclude that both Lactobacilli and Bifidobacteria can help prevent and even treat acute diarrhea in children, and a number of species appear to be effective.
ANTIBIOTIC-ASSOCIATED DIARRHEA
In our bacteria-phobic world, packed with antibacterial dish and bathroom soaps, antibiotics are considered a miracle drug to many. However, the overuse of antibiotics and antibiotic products has resulted in some negatives, including the development of antibiotic-resistant bacteria and a rise in antibiotic-associated ailments. Antibiotic-resistant bacteria, or superbugs, are discussed in more detail in Chapter 16. One the most severe side effects of antiobiotic use is antibiotic-associated diarrhea.
Antibiotics are commonly used in developed countries to treat illness. Antiobiotics are drugs that kill bacteria. Some people are using antibiotics for illnesses that are not caused by bacteria, such as the common cold, which is caused by viruses. A national survey of Canadians done by Ipsos-Reid discovered that 30% of consumers believe that most colds and flus can be treated successfully with antibiotics. This is incorrect. Most colds and flus are caused by viruses and as such would not be aided by antibiotics. This misconception causes an overuse of antibiotics, which in turn leads to an increased number of cases of antibiotic-associated diarrhea.
This prevalent consumer belief that antibiotics can treat the common cold may explain the high use of antibiotics in developed countries. Also, physicians are over-prescribing antibiotics. When asked, 53% of Canadian consumers said they had been prescribed an antibiotic in the previous three years. That is a lot of antibiotic use.
Antibiotics are very effective at killing bacteria in the body; however, you will recall that antibiotics do not kill just the bacteria that is making you sick. Antibiotics kill both the bad and the good bacteria. While antibiotics destroy the bad bacteria that is making you sick, they also kill the probiotics that are vital to your health and your immunity.
Antibiotics do not just kill most of the probiotics in your body; they also affect their ability to colonize. This means that probiotics cannot grow when you are taking antibiotics. The result is a compromised microflora in your intestines. Without probiotics, bad microbes can invade you and cause illness. Most commonly, the bad microbes cause diarrhea, hence the term antibiotic-associated diarrhea.
About 39% of patients who receive antibiotics will develop diarrhea.
Antibiotic-associated diarrhea is a common problem. The incidence of antibiotic-associated diarrhea in hospitals has been found to range from 3% to 29%. Antibiotic-associated diarrhea has been associated with an increased number of days of hospitalization and higher medical costs. Probiotics are an attractive option for preventing antibiotic-associated diarrhea as they are becoming increasingly available, are low in cost and have a lack of side effects. As probiotics don’t have the problems associated with antibiotics, they are becoming a popular way for people to prevent bacterial infections, thus reducing the need for antibiotic use.
The gastrointestinal tract is the major portal of entry of pathogens.
Probiotic Therapy and Antibiotics
Probiotic therapy involves using probiotics to balance the microflora and thus helps the intestinal barrier prevent infection from bad microbes. This type of therapy is particularly important when antibiotics are used because the natural healthy balance of microflora has been drastically altered. In other words, when you take antibiotics it kills off your natural defenses in your intestines, and this is a problem. The intestines face the most attacks from bad microbes; your intestines are the major entry point into your body for pathogens. Research has uncovered a unique interaction between the intestines and probiotics. Probiotics help the intestinal lining fight off attacks from bad microbes.
What Types of Bad Microbes Do We Ingest?
We have already seen that Rotavirus is an example of a bad microbe that can have grave consequences: it causes diarrhea. However, any bad microbe can attach to an intestinal cell and colonize there, releasing toxins and causing damage that leads to diarrhea. It is particularly easy for a bad microbe to attach to your intestinal cells if antibiotics have washed away the probiotics which normally prevent infection of bad microbes.
Probiotics successfully prevent antibiotic-associated diarrhea.
Antibiotic-associated diarrhea can be the result of an overgrowth of Clostridium difficile, a bad microbe that lives in your intestines. Normally, probiotics keep this nasty microbe under control and it is not allowed to grow and cause you to feel ill. The changes that antibiotics cause to the intestinal environment offers Clostridium difficile a chance to flourish. Since antibiotics can reduce the ability of probiotics to colonize, antibiotic use can commonly lead to growth of bad microbes such as Clostridium. This is a major problem in elderly people and can lead to serious diarrhea and at times death.
A Deadly Bacteria
Clostridium difficile (C. difficile) is a type of bacteria that can be found in human feces. When antibiotics kill your good intestinal bacteria, C. difficile is allowed to grow. When it grows, C. difficile produces toxins that damage the intestines and may cause diarrhea. C. difficile disease is usually mild but sometimes can be severe. In severe cases, surgery may be needed, and in extreme cases C. difficile may cause death. Symptoms include watery diarrhea, fever and abdominal pain or tenderness. It is the most common cause of infectious diarrhea in hospitals or long-term care homes. Who gets C. difficile? It usually occurs after the use of antibiotics. Old age, presence of other serious illnesses and poor overall health may increase the risk of severe disease. Diagnosis of C. difficile disease can be done with a simple stool test and it is commonly treated with antibiotics. However, probiotics would be beneficial in this probiotic poor intestinal situation. C. difficile is spread by fecal-oral contaimination. Bacteria in the stool can contaminate surfaces such as toilets, handles, bedpans or commode chairs. Hand washing is vital to reducing the spread of this potentially deadly disease. Read more about this illness and how probiotics can help in Chapter 16.
Probiotics for Prevention of Antibiotic-Associated Diarrhea
It is wonderful that probiotics can help alleviate antibiotic-associated diarrhea; however, can probiotics prevent antibiotic-associated diarrhea? Yes, they can. In 2002, a group of scientists reviewed all of the research available on the ability of probiotics to prevent antibiotic-associated diarrhea. This type of review is called a meta-analysis. The review consisted of nine randomized, double-blind, placebo-controlled trials—the gold standard of trials. The researchers concluded that probiotics can be used successfully to prevent antibiotic-associated diarrhea; in particular the probiotics L. acidophilus, Enterococcus faecium, L. bulgaricus and S. boulardii have the best potential in this situation. Two of the trials included children.
Bifidobacterium longum has also been shown to reduce the number of times and length of antibiotic-associated diarrhea. An interesting strain, Bifidobacterium bifidum, is actually able to neutralize the toxins that bad microbes produce. This means that the toxins cannot damage your intestinal cells and that translates into no more diarrhea.
Which specific strains are best for antibiotic-associated diarrhea has not yet been conclusively determined by the scientific community. However, species of both the Bifidobacteria and Lactobacilli genus have shown promise as supportive tools in reducing the loss of immune strength in the intestinal tract during health challenges, including antibiotic use. As such, probiotics are a possible way of preventing antibiotic-associated diarrhea. The relative lack of side effects makes probiotics even more attractive in the use of antibiotic-associated diarrhea.
Certain probiotic strains have been found to reduce the incidence of Clostridium difficile infection when taken concurrently with antibiotics; however, these strains have not yet been shown to directly treat a Clostridium difficile infection. Clostridium difficile produces toxins that cause a series of symptoms in the host. This particularly devastating condition, which is causing havoc in cities across North America, including Montreal, will be discussed in more detail in Chapter 16.
Probiotics can be taken with antibiotics.
Can you take a probiotic at the same time as an antibiotic? In all nine of the trials reviewed in the meta-analysis above, probiotics were given at the same time as antibiotics. In fact, a number of the studies noted that probiotics can offer you health benefits even when they are taken at the same time as antibiotics. S. boulardii is a well-known probiotic that can reduce the severity and duration of diarrhea caused by antibiotic use. This is because S. boulardii can quickly cause changes to cells in your intestine that helps them fight off any invading bad microbes. Clinicians who are experts on probiotics are suggesting that a probiotic be taken at the same time as an antibiotic. They do not mean in the same mouthful, as the antibiotic would kill the probiotic before it has a chance to help you. Clinicians suggest taking your probiotic and antibiotic about four hours apart to reduce their interaction. Four hours is plenty of time for a probiotic to have time to attach to your intestinal cells. If you happen to take them closer together, you would not lose all of the benefits of the probiotics. One mouthful of antibiotics cannot kill all of the probiotics in your body; thus, if you keep replacing your probiotics between dosages of antibiotics, you will always have some probiotics present to help you fight off bad microbes that can cause diarrhea.
In conclusion, antibiotics kill the probiotics in your body, reducing your ability to fight off bad microbes that can cause diarrhea. Research has found that probiotics, including Saccharomyces boulardii , Bifidobacteria and Lactobacilli can destroy bad microbes, help the body defend itself (boost immunity) and thus prevent and treat diarrhea associated with antibiotic use. Probiotics can be taken at the same time as antibiotics.
PROBIOTICS FOR TREATING INFECTIOUS DIARRHEA
Probiotics are effective at fighting infectious diarrhea. This is done through a number of mechanisms:
• Promoting the production of mucous by intestinal cells acting like fly-tape and making it hard for bad microbes to attach to these cells
• Competing with bad microbes for binding sites on intestinal cells and nutrients needed to help them grow
• Producing acidic substances that lower the pH of the intestines, something not liked by bad microbes
• Increasing intestinal movement, which means bad microbes get carried out with the feces and cannot sit around and grow in your intestines.
Probiotics also turn on genes that control innate immunity, which further contributes to the elimination of pathogens. Perhaps one of the most fascinating things that some probiotic strains can do is produce bacteriocins (antimicrobials)—substances that kill bad microbes in your intestines. They function like home-made antibiotics that do not kill probiotics. For example, Lactobacillus GG can produce an antimicrobial substance that prevents the growth of the following bad microbes: Escherichia coli, Salmonella, Clostridium difficile, Bacteroides fragilis and Streptococci. For more information on the mechanisms by which probiotics affect the immune system and help your intestines become a barrier that prevents bad microbes from infecting you, see Chapter 3.
Some probiotic strains have antibiotic-like actions but do not kill probiotics.
PROBIOTICS FOR TREATMENT AND PREVENTION OF TRAVELER’S DIARRHEA
No one likes to travel with a roll of toilet paper in their purse. However, it is true: travelers commonly suffer from acute diarrhea. Medical professionals would say, “Ingestion of foreign bacteria and viruses can cause acute diarrhea.” What they mean is that if you eat a bad microbe on your travels that your body has not seen before, you’re less able to fight it off and can end up with diarrhea. No one visits the buffet at their favorite resort with a microscope hoping to identify any microbes that might be living on the fruit salad. Let’s face it—avoiding foreign microbes when traveling is virtually impossible. Hand washing can eliminate a certain amount of exposure; however, it may not be enough.
Acute diarrhea can be a particular problem for travelers visiting areas in which there are low hygiene standards.
If repeated hand washing and careful food choices do not prevent exposure to bad microbes, luckily there are probiotics that can help you. Probiotics can attack these invaders before they attach, colonize and cause diarrhea. The good news is that probiotics can help you prevent getting traveler’s diarrhea.
Research studies have found that probiotics can prevent bad microbes from causing traveler’s diarrhea. The ability of a probiotic to prevent traveler’s diarrhea is dependent on many factors including the strain of the probiotic, the number of strains/species used, the destination of the traveler and the way in which the bad microbe causes diarrhea. L. rhamnosus GG and S. boulardii have been shown in three double-blind, randomized control trials to offer a preventative effect against acute diarrhea commonly picked up when traveling. These two species of probiotics are good items to include on your next packing list.
Researchers are not convinced that there is enough evidence to support a medical recommendation to use probiotics to prevent traveler’s diarrhea. They still suggest that the best way to prevent traveler’s diarrhea is to practice proper hygiene. Yes, this is true; however, why not double-up on your protection? Research suggests that probiotics offer some protection to travelers, particularly those in high-risk areas. More studies may help us make a more concrete recommendation to travelers to use probiotics as a means to prevent diarrhea. I always include probiotics in my vacation bathroom kit.
SUMMARY
Diarrhea is a major health problem that affects people of all ages and health conditions. Diarrhea is a particular problem in children and the elderly as it reduces their ability to absorb nutrients and can cause them to become dehydrated. There are two types of diarrhea: chronic and acute. Chronic diarrhea is usually due to a problem with the intestines’ ability to function, such as irritable bowel disease. Acute diarrhea is caused by an infection. In the intestines’ bad microbes can produce toxins that damage the cells of the microvilli (finger-like projections on the lining of the small intestine that are responsible for most of the nutrient absorption by the body). The damage caused by these toxins leads to diarrhea. Probiotics are effective in the management and potentially in the prevention of diarrhea. Probiotics help the intestinal cells prevent bad microbes from attaching and causing an infection. There have been three meta-analyses (reviews of all of the research available) looking at the ability of probiotics to help fight diarrhea. The studies used in the review were all of high quality—double-blind and placebo-controlled. There is a convincing amount of evidence that supports ths use of probiotics to prevent and treat cases of acute diarrhea in children, antibiotic-associated diarrhea and traveler’s diarrhea. For the prevention and treatment of diarrhea, probiotics are a safe, effective option.
