What is Diarrhea?
Normally, the amount of water in poop is about 10 milliliters per kilogram per day in babies and young children, or around 200 grams a day for teenagers and adults. Diarrhea happens when there’s an extra amount of water in the poop due to the gut not working properly and not absorbing ions, different substances, and water as it should.
Diarrhea is defined as acute, or sudden, when someone has three or more loose or watery poops a day for up to 14 days. However, chronic or persistent diarrhea is when it lasts for more than 14 days. Acute diarrhea is usually caused by an infection. Non-infectious causes become more likely as the diarrhea lasts longer. Recognizing whether diarrhea is acute or chronic is crucial because the treatment and care depend on its duration and cause. Drinking plenty of fluids is a key part of managing diarrhea, to make sure the body stays hydrated. To prevent infectious diarrhea, proper handwashing is crucial to stop the spread of germs.
Sometimes people use the term “acute gastroenteritis” to mean “acute diarrhea,” but technically these terms aren’t the same. Gastroenteritis suggests that both the stomach and the small intestine are involved, but in reality, the stomach is almost never affected in acute diarrhea, even if it’s caused by infection. Also, enteritis, or inflammation of the intestine, is not always present. Some examples of infectious diarrhea without enteritis are cholera and shigellosis. Therefore, it’s more accurate to use the term “acute diarrhea” instead of “acute gastroenteritis.”
What Causes Diarrhea?
Diarrhea can be broken down into two main categories: short-term (acute) or long-term (chronic), and it can either be caused by infections or other reasons. Acute diarrhea lasts for less than two weeks and is most often due to an infection, usually a viral one. This type of diarrhea doesn’t tend to last very long. Chronic diarrhea, on the other hand, goes on for more than two weeks and isn’t usually caused by an infection. Common causes of chronic diarrhea can include problems with nutrient absorption, inflammatory bowel disease, or side effects from medication.
To diagnose and manage diarrhea, it’s important to figure out what’s causing it. Some things healthcare providers consider include:
* The stool’s characteristics, such as how solid or liquid it is, its color, its volume, and how often bowel movements occur
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Whether any other symptoms from the intestines are present, like nausea or vomiting, fever, and stomach pain
Possible exposure to daycare facilities where common pathogens like rotavirus, astrovirus, calicivirus; Shigella, Campylobacter, Giardia, and Cryptosporidium species are commonly present
Recent consumption of possibly contaminated, like raw foods
Participation in activities that could expose one to contaminated water, like swimming pools, camping, or oceanic areas
Travel history, since certain pathogens are more common in specific areas; for example, a pathogen called enterotoxigenic Escherichia coli is often found in specific places
Exposure to animals, such as young dogs or cats with Campylobacter or turtles with Salmonella, which have been historically associated with diarrhea
Underlying conditions or triggers that make a person more likely to have diarrhea, like recent hospital stays, antibiotic use, and suppression of the immune system
Risk Factors and Frequency for Diarrhea
Norovirus is responsible for about 20% of all cases of infectious diarrhea and is as common in children as it is in adults. It causes over 200,000 deaths in developing countries each year. In the past, rotavirus used to be the main cause of severe diarrhea in young kids worldwide. However, the number of diarrhea cases caused by rotavirus has decreased thanks to vaccination programs.
In underdeveloped areas, on average, kids under five years old have three instances of diarrhea each year. But in some regions, the number goes up to six to eight instances per child annually. Adding to the problem in these places, poor nutrition also contributes to the development of diarrhea.
Conditions such as inflammatory bowel disease, Crohn’s disease, and ulcerative colitis often lead to chronic diarrhea. In Europe, the rate of ulcerative colitis and Crohn’s disease has risen from 6.0 and 1.0 cases per 100,000 people per year in 1962 to 9.8 and 6.3 cases per 100,000 people per year in 2010.
A study found that in Germany in 2012, there were 83 cases of Clostridium difficile infection (a type of bacteria that can cause diarrhea) for every 100,000 people. The likelihood of a recurrence of the infection went up with each relapse.
In the United States, before the rotavirus vaccine was introduced in 2006, there was one hospitalization for diarrhea in every 23 to 27 children by the age of five. In addition, over 50,000 hospitalizations were recorded. As a result, rotavirus was determined to be the cause of 4-5% of all hospitalizations of children and cost approximately 1 billion US dollars.
Signs and Symptoms of Diarrhea
Acute diarrhea is usually not serious in developed areas and typically disappears within a few days. The length and symptoms of the illness can vary based on the cause, the individual’s general health and other factors. For example, rotavirus often comes with symptoms like vomiting, dehydration and it can also cause one to miss more workdays compared to diarrhea caused by other factors.
Understanding certain characteristics of the diarrhea such as volume, color, consistency and frequency can help determine its source. Here are some features associated with diarrhea:
- The color and amount of stool – either watery or containing mucus or blood
- The volume of the stool – either large or small
- The frequency of bowel movements – from increased to extremely increased
- The presence of blood in the stool – could be present but usually not visible to the naked eye, or usually clearly visible blood
- The pH of the stool – may be less than 5.5 or more than 5.5
- Presence of white blood cells in the stool or in the serum (blood)
- Common pathogens associated with diarrhea, like Rotavirus, Adenovirus amongst others.
In childcare centers, certain diseases can spread faster including rotavirus, astrovirus, calicivirus, Shigella, Giardia, Campylobacter, and Cryptosporidium.
Eating habits also play an essential role. Consuming raw or contaminated food is common with infectious diarrhea. For example, specific food items are often associated with particular organisms causing diarrhea:
- Dairy products – Campylobacter and Salmonella species
- Eggs – Salmonella species
- Meats – Clostridium perfringens, Campylobacter, Aeromonas, and Salmonella
species - Poultry – Campylobacter species
- Ground beef – Enterohemorrhagic E coli
- Seafood – Astrovirus, Aeromonas, Plesiomonas, and Vibrio species
- Pork – C perfringens, Y enterocolitica
- Oysters – Calicivirus, Plesiomonas, and Vibrio species
- Vegetables – Aeromonas species and C perfringens
Consideration should also be given to the child’s juice consumption when examining children suffering from persistent diarrhea, excessive gas, bloating, and stomach pain.
There are also certain causes of diarrhea related to specific environments. For instance, swimming pools can be a source of Shigella species and Aeromonas organisms, while Giardia, Cryptosporidium, and Entamoeba organisms can survive in chlorinated water. Thus, the presence of these parasites should be considered if the water is contaminated.
Travel history matters as some pathogens causing infectious diarrhea are more common in specific areas. For example, Enterotoxigenic E coli is the predominant cause of travelers’ diarrhea. Below are other common pathogens related to certain regions:
- General foreign travel – Enterotoxigenic E coli, Aeromonas, Giardia,
Plesiomonas, Shigella, and Salmonella species - New Guinea – Clostridium perfringens
- Africa – Entamoeba species, Vibrio cholerae
- South and Central America – Entamoeba species, V cholerae, enterotoxigenic
E coli - Asia – Vibrio cholerae
- Australia, Canada, Europe – Yersinia species
- India – Entamoeba species, V cholerae
- Japan – Vibrio parahaemolyticus
- Mexico – Aeromonas, Entamoeba, Plesiomonas, and Yersinia species
Testing for Diarrhea
Acute diarrhea often resolves itself and usually doesn’t need lab tests or imaging. However, if someone has bloody diarrhea or is very sick, the doctor may order a stool culture to check for bacterial infections. If blood is found in the stool, additional tests may be needed. A patient who recently used antibiotics or was in a hospital might need to be tested for a specific type of infection, known as Clostridium difficile infection.
People who have had diarrhea for a long time (chronic diarrhea) will likely have different tests run to find the cause. These can include complete blood count, basic metabolic panel, thyroid hormone test, erythrocyte sedimentation rate, liver panel, and a stool analysis. Depending on the person’s symptoms, the doctor will then order more specific tests based on their initial findings. For instance, chronic diarrhea can be categorized as watery, fatty, or inflammatory. Tests will be ordered based on where the doctor thinks the problem might be originating from.
In cases of diarrhea, if stool pH is less than 5.5 or if there is an overabundance of specific substances, it could indicate a problem digesting carbohydrates, often as a result of viral illnesses. This is usually a temporary issue. Certain types of infections in the large bowel can cause white blood cells to be shed into the stool. If white blood cells are found in stools, it rules out certain types of bacteria and viruses as the cause.
If a stool sample can’t be examined within two hours of being collected, it should be refrigerated or placed in a transport medium. The chance of finding something in a stool sample is generally low, but it can still provide important information, especially if the sample tests positive. In some cases, it’s crucial to test for certain types of bacteria if there are signs of inflammation in the colon or if there is an increase in white blood cells in the stool.
In case of blood in stools or inflammation in the colon, testing for a specific type of bacteria called Clostridium difficile may be necessary. It’s worth noting that sudden onset diarrhea could happen as a result of this infection, even if the patient has not used antibiotics recently. If a particular type of E coli bacteria is found in the stool of someone who ate undercooked ground meat, more testing should be done since it can lead to a serious condition called hemolytic uremic syndrome.
Testing for a common cause of diarrhea in children, called rotavirus, can be done through specific tests on the stool. Similarly, there are tests to detect adenovirus antigens. To check for parasites, the stool can be examined under a microscope to look for eggs and parasites, which should be done every three days or so.
Treatment Options for Diarrhea
One vital part of managing diarrhea is the replacement of lost fluids and electrolytes. Patients are usually encouraged to drink fluids like diluted fruit juice, Pedialyte or Gatorade. In serious cases, they might need IV fluids. Eating foods that are low in fiber could help firm up loose stools. A bland diet composed of bananas, toast, oatmeal, white rice, applesauce and soup/broth could be beneficial. Certain medications might be used to decrease the number of bowel movements. However, these shouldn’t be used by adults with bloody diarrhea or a high fever as they could make severe intestinal infections worse. Antibiotics can be considered in serious cases. Probiotics can shorten duration and lessen severity of diarrhea symptoms.
Chronic diarrhea treatment will depend on the cause. Fecal studies, lab tests, or imaging may be required to help diagnose the underlying issue. Some cases might even need more invasive procedures such as colonoscopy or upper endoscopy.
The CDC recommends specific treatment methods for acute diarrhea in children. Children’s age, weight, birth history, health, temperature, bowel movement and overall symptoms must be considered for diagnosis and referral. Dehydration could be a major concern. Its treatment depends on its extent. With minimal to no dehydration, an oral rehydration solution might be enough. With mild to moderate dehydration, the same solution could be given over a few hours. For severe cases with poor mental state and blood circulation, IV fluids might be needed. For all ranges of dehydration, following each episode of diarrhea or vomiting, specific amounts of an oral rehydration solution should be given based on bodyweight.
For some specific non-viral causes of diarrhea, certain antibiotics or medical treatments can be recommended. These include different medications for varying instances of bacterial species responsible for the diarrhea.
What else can Diarrhea be?
If a patient comes to the doctor complaining of diarrhea, there are several different conditions that the doctor might consider as the cause of the symptoms. These may include:
- Appendicitis
- Carcinoid tumor, a rare type of cancer
- Giardiasis, a small intestine infection caused by a parasite
- Glucose-galactose malabsorption, a rare genetic metabolic disorder
- Intestinal enterokinase deficiency, an enzyme deficiency in the intestines
- Intussusception, a condition where part of the intestine ‘telescopes’ into another part
- Meckel’s diverticulum, a small pouch in the small intestine that is present from birth
- Crohn’s disease in children
- Hyperthyroidism in children, where the thyroid gland is overactive
- Malabsorption syndromes in children, conditions that prevent the absorption of nutrients through the small intestine
The doctor will evaluate the patient’s symptoms, medical history and possibly perform tests to find the exact cause of the diarrhea.
What to expect with Diarrhea
In areas with good healthcare, the outlook for diarrhea treatment is generally positive. However, statistics show a rise in deaths related to diarrhea among children in the US from the mid-1980s to 2006. Between 2005 and 2007, there were 1087 recorded infant deaths associated with diarrhea, with 86% of these fatalities happening in infants with low birth weight (less than 2500 g).
Risks factors include being male, being of black ethnicity, and having a low Apgar score (less than 7), a measure used to quickly summarize the health of newborns.
Most of these deaths are commonly caused by dehydration and follow-up malnutrition. In severe dehydration cases, infusions should be given. When malnutrition happens, it becomes critical unless intravenous nutrition, a method to feed nutrients directly into the bloodstream, is initiated in a hospital setup.
Possible Complications When Diagnosed with Diarrhea
Several common pathogens can cause various complications. These include:
- Aeromonas caviae: It can cause complications like Intussusception, hemolytic-uremic syndrome (HUS), and gram-negative sepsis.
- Campylobacter species: These pathogens can lead to bacteremia, meningitis, urinary tract infections, pancreatitis, cholecystitis, and Reiter syndrome (RS).
- C difficile: It can cause chronic diarrhea.
- C perfringens: This pathogen can cause Enteritis necroticans.
- Plesiomonas species: They can lead to septicemia.
- Enterohemorrhagic E coli O157:H7: It can cause HUS.
- Enterohemorrhagic E coli: It can lead to hemorrhagic colitis.
- Salmonella species: These pathogens can cause seizures, RS, HUS, bowel perforation, enteric fever.
- Vibrio species: They can cause rapid dehydration.
- Giardia species: These pathogens can lead to chronic fat malabsorption.
- Rotavirus: It can cause isotonic dehydration and carbohydrate intolerance.
- Y enterocolitica: This pathogen can cause appendicitis, intussusception, perforation, toxic megacolon, peritonitis, cholangitis, bacteremia, RS.
- Cryptosporidium species: They can cause chronic diarrhea.
- Entamoeba species: These pathogens can lead to liver abscess and colonic perforation.
Preventing Diarrhea
Education plays a key role in both preventing and treating diseases. Rehydrating the body sufficiently can help to avoid dehydration. It’s also important to start eating as soon as possible, as the lining of the intestines heals faster this way. When taking care of affected individuals, it’s crucial to maintain hygiene and prepare food correctly to prevent future infections and their spread.
Washing hands thoroughly can help prevent the transmission of infectious diarrhea. People with infectious diarrhea should not go back to work, school, or daycare until they no longer show symptoms. Experts advise parents to get their kids vaccinated against rotavirus, a common cause of viral diarrhea. If a patient is on antibiotics, it might be helpful to consider probiotic treatments to prevent a certain type of serious diarrhea caused by C diff bacteria.
For those traveling to less developed countries, to avoid traveler’s diarrhea, drinking bottled water and sticking to thoroughly cooked hot meals, while avoiding raw fruits and vegetables is recommended. This includes using bottled water even for brushing teeth. While people generally don’t need to take antibiotics as a preventive measure, they may be suitable for individuals with existing medical conditions that could be worsened by diarrhea.