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Barium Swallow (Esophagography, Esophagogram) Procedure Overview What is a barium swallow? A barium swallow is a radiographic (x-ray) examination of the upper gastrointestinal (GI) tract, specifically the pharynx (back of mouth and throat) and the esophagus (hollow tube of muscle extending from below the tongue to the stomach). The pharynx and esophagus are made visible on x-ray film by a liquid suspension called barium sulfate (barium). Barium highlights certain areas in the body to create a clearer pi...

Cholecystectomy (Gallbladder Removal, Open Cholecystectomy, Laparoscopic Cholecystectomy) Procedure Overview What is a cholecystectomy? A cholecystectomy is the surgical removal of the gallbladder, an organ located just under the liver on the upper right quadrant of the abdomen. The gallbladder stores and concentrates bile, a substance produced by the liver and used to break down fat for digestion. Types of cholecystectomies: Click Image to Enlarge The gallbladder may be removed in one of two ways: open...

Cholecystography (Gallbladder Series, GB Series, Oral Cholecystography, Oral Cholecystogram, X-rays of the Gallbladder) Procedure Overview What is cholecystography? Cholecystography is an x-ray procedure used to examine the gallbladder when gallstones are suspected. A contrast dye is swallowed prior to the procedure. The contrast dye allows for better visualization of gallstones and other abnormalities of the gallbladder that cannot be seen on a standard x-ray of the abdomen. X-rays use invisible electr...

Computed Tomography (CT or CAT) Scan of the Liver and Biliary Tract (CT Scan of the Liver, Biliary Tract, Pancreas, Spleen, and Gallbladder) Procedure Overview What is a CT or CAT scan of the liver and biliary tract? Computed tomography (CT or CAT scan) is a noninvasive diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of...

Computed Tomography (CT or CAT) Scan of the Pancreas (Pancreas CT Scan) Procedure Overview What is a CT or CAT scan of the pancreas? Computed tomography (CT or CAT scan) is a noninvasive diagnostic imaging procedure that uses a combination of x-rays and computer technology to produce cross-sectional images (often called slices), both horizontally and vertically, of the body. A CT scan shows detailed images of any part of the body, including the bones, muscles, fat, and organs. CT scans are more detailed...

Endoscopic Retrograde Cholangiopancreatography (ERCP, ERCP of the Biliary and Pancreatic Ducts) Procedure Overview What is endoscopic retrograde cholangiopancreatography? Endoscopic retrograde cholangiopancreatography (ERCP) is a diagnostic procedure that allows the physician to diagnose and treat problems in the liver, gallbladder, bile ducts, and pancreas. The procedure combines x-ray and the use of an endoscope - a long, flexible, lighted tube. The scope is guided through the patient's mouth and thro...

Esophagogastroduodenoscopy (EGD, Upper Gastrointestinal Endoscopy, Upper GI Endoscopy, Gastroscopy, Esophagoscopy) Procedure Overview What is an esophagogastroduodenoscopy? Esophagogastroduodenoscopy (EGD) is a diagnostic procedure that allows the physician to diagnose and treat problems in the upper gastrointestinal (UGI) tract. The physician uses a long, flexible, lighted tube called an endoscope. The endoscope is guided through the patient's mouth and throat, then through the esophagus, stomach, and ...

Gallbladder Scan (Cholescintigraphy, Liver-Biliary Scan, Hepatobiliary Iminodiacetic Acid [HIDA], Gallbladder Radionuclide Scan) Procedure Overview What is a gallbladder scan? A gallbladder scan is a specialized radiology procedure used to assess the function and structure of the gallbladder. This procedure may also be referred to as a liver-biliary scan because the liver often is examined as well due to its proximity and close functional relationship to the gallbladder. A gallbladder scan is a type of ...

Liver Biopsy (Biopsy-Liver, Percutaneous Liver Biopsy) Procedure Overview What is a liver biopsy? A liver biopsy is a procedure in which tissue samples from the liver are removed for examination under a microscope to look for signs of damage or disease. It is used to diagnose many liver conditions. During a liver biopsy, tissue samples are removed with a special needle to determine if cancer or other abnormal cells are present, or to determine how well the liver is working. There are three types of live...

Liver Scan (Liver-Spleen Scan, Liver Scintigraphy) Procedure Overview What is a liver scan? A liver scan is a specialized radiology procedure used to examine the liver to identify certain conditions or to assess the function of the liver. A liver scan may also be used to follow the progress of treatment of certain conditions. This procedure may also be referred to as a liver-spleen scan because the spleen often is examined as well due to its proximity and close functional relationship to the liver. A li...

Liver Transplantation Procedure (Liver Transplant, Hepatic Transplant) Procedure Overview What is a liver transplant? A liver transplant is a surgical procedure performed to replace a diseased liver with a healthy liver from another person. The liver may come from a deceased organ donor or from a living donor. Family members or individuals who are unrelated but make a good match may be able to donate a portion of their liver. This type of transplant is called a living transplant. Individuals who donate ...

Pancreas Scan (Pancreas Scintigraphy) Procedure Overview What is a pancreas scan? A pancreas scan is a specialized radiology procedure used to assess the pancreas for the presence of a specific type of tumor. A pancreas scan is a type of nuclear radiology procedure. This means that a tiny amount of a radioactive substance is used during the procedure to assist in the examination of the pancreas. A pancreas scan may also be used to treat certain malignant tumors of the pancreas. In many nuclear medicine ...

Upper Gastrointestinal Series (UGI, Upper GI Series, GI Series, Upper Gastrointestinal Tract X-ray) Procedure Overview What is an upper gastrointestinal series? An upper gastrointestinal series (UGI) is a radiographic (x-ray) examination of the upper gastrointestinal (GI) tract. The esophagus, stomach, and duodenum (first part of the small intestine) are made visible on x-ray film by a liquid suspension. This liquid suspension may be barium or a water-soluble contrast such as Gastrografin TM . If only t...

Abdominal Ultrasound (Abdominal Ultrasonography, Abdominal Sonography, Abdominal Echography) Procedure Overview An abdominal ultrasound is a noninvasive (the skin is not pierced) procedure used to assess the organs and structures within the abdomen, such as the liver, gallbladder, pancreas, bile ducts, spleen, and abdominal aorta. Ultrasound technology allows quick visualization of the abdominal organs and structures from outside the body. Ultrasound may also be used to assess blood flow to abdominal or...

Abdominal X-rays (Flat Plate of the Abdomen, Abdominal Radiography, KUB [Kidneys, Ureters, Bladder] X-ray) Procedure Overview X-rays use invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs on film. Standard x-rays are performed for many reasons, including diagnosing tumors or bone injuries. X-rays are made by using external radiation to produce images of the body, its organs, and other internal structures for diagnostic purposes. X-rays pass through body tissu...

Appendectomy (Appendix Removal, Laparoscopic Appendectomy, Open Appendectomy) Procedure Overview What is an appendectomy? An appendectomy is the surgical removal of the appendix, a tube about six inches long or less that branches off the large intestine. The procedure is performed to treat appendicitis, an inflammation of the appendix caused by infection. Acute appendicitis is the most common condition of the abdomen to require emergency surgery. Because of the likelihood of the appendix rupturing and c...

Anatomy and Function of the Liver Anatomy of the liver: The liver is located in the upper right-hand portion of the abdominal cavity, beneath the diaphragm and on top of the stomach, right kidney, and intestines. The liver, a dark reddish-brown organ that weighs about 3 pounds, has multiple functions. Click Image to Enlarge There are two distinct sources that supply blood to the liver: Oxygenated blood flows in from the hepatic artery. Nutrient-rich blood flows in from the hepatic portal vein. The liver...

The Liver To learn more about the intricate process of liver transplantation, it is important to first learn about the liver and its components. Listed in the directory below you will find additional information regarding the anatomy of the liver and liver transplantation, for which we have provided a brief overview. Anatomy and Function of the Liver Liver Transplantation

Hepatoblastoma What is hepatoblastoma? Hepatoblastoma is a very rare cancerous tumor that originates in the liver. The liver is one of the largest organs in the body. The primary functions of the liver include filtering and storing blood. The liver consists of right and left lobes. Most hepatoblastoma tumors originate in the right lobe. This disease primarily affects children from infancy to about 3 years of age. Hepatoblastoma cancer cells can spread (metastasize) to other areas of the body. The most c...

Hepatitis in Children What is hepatitis? Hepatitis is the inflammation of the liver and can result in liver cell damage and destruction. What causes hepatitis? Hepatitis in children has many different origins or causes. A child may contract hepatitis from exposure to a viral source. The following is a list of some of the viruses associated with hepatitis: hepatitis viruses - six main types of the hepatitis virus have been identified, including hepatitis A, B, C, D, E, and G. cytomegalovirus (CMV) - a vi...

Hyperbilirubinemia and Jaundice What is hyperbilirubinemia? Hyperbilirubinemia is a condition in which there is too much bilirubin in the blood. When red blood cells break down, a substance called bilirubin is formed. Babies are not easily able to get rid of the bilirubin and it can build up in the blood and other tissues and fluids of the baby's body. This is called hyperbilirubinemia. Because bilirubin has a pigment or coloring, it causes a yellowing of the baby's skin and tissues. This is called jaun...

Necrotizing Enterocolitis What is necrotizing enterocolitis? Necrotizing enterocolitis (NEC) is a serious intestinal illness in babies. "necrotizing" means damage and death of cells "entero" refers to the intestine "colitis" means inflammation of the colon (lower part of the intestine) Although NEC may develop in low-risk newborns, most cases occur in premature babies. NEC is more common in babies weighing less than 1,500 grams (3 pounds, 4 ounces). What causes necrotizing enterocolitis? It is not clear...

Pyloric Stenosis What is pyloric stenosis? Pyloric stenosis is a problem that affects babies between 2 and 8 weeks of age and causes forceful vomiting that can lead to dehydration. It is the second most common problem requiring surgery in newborns. The lower portion of the stomach that connects to the small intestine is known as the pylorus. In pyloric stenosis, the muscles in this part of the stomach enlarge, narrowing the opening of the pylorus and eventually preventing food from moving from the stoma...

Diaphragmatic Hernia What is a diaphragmatic hernia? A diaphragmatic hernia is a birth defect, which is an abnormality that occurs before birth as a fetus is forming in the mother's uterus. An opening is present in the diaphragm (the muscle that separates the chest cavity from the abdominal cavity). With this type of birth defect, some of the organs that are normally found in the abdomen move up into the chest cavity through this abnormal opening. Click Image to Enlarge Click Image to Enlarge There are ...

Digestive Disorders in Children There are many digestive disorders that may require clinical care by a physician or other healthcare professional. Some digestive disorders are congenital (present at birth) while others occur after birth. Listed in the directory below is some additional information regarding digestive disorders in high-risk newborns, for which we have provided a brief overview. Necrotizing Enterocolitis Gastroesophageal Reflux (GER)

Gastroesophageal Reflux (GER) What is gastroesophageal reflux (GER)? Gastroesophageal reflux (GER) is a digestive disorder that is caused by gastric acid flowing from the stomach into the esophagus. Gastroesophageal refers to the stomach and esophagus, and reflux means to flow back or return. Gastroesophageal reflux is the return of acidic stomach juices, or food and fluids, back up into the esophagus. Gastroesophageal reflux is common in babies, although it can occur at any age. It is the most common c...

Colic What is colic? Colic is a problem that affects some babies during the first three to four months of life. It is defined by the "rule of three": crying at least 3 hours per day, more than 3 days per week, and for 3 weeks duration or more. It can be very stressful and frustrating to parents. Colic usually begins suddenly, with loud and mostly continuous crying. What causes colic? Physicians are not certain what causes colic. There are several theories about why colic may or may not occur, including ...

Common Children's Digestive Problems There are many problems that may affect a child's digestive system that require clinical care by a physician or other healthcare professional. Listed in the directory below are some, for which we have provided a brief overview. Colic Diarrhea Food Allergies Lactose Intolerance

Constipation in Children Click Image to Enlarge What is constipation? Constipation is defined as: a decrease in frequency of bowel movements, compared to a child's usual pattern (some physicians define constipation as fewer than three bowel movements per week). the passage of hard, often times large caliber, dry bowel movements. bowel movements that are difficult or painful to push out. However, normal stool elimination may consist of having a bowel movement three times a day or three times a week; it d...

Crohn's Disease in Children What is Crohn's disease? Crohn's disease is an inflammatory bowel disease (IBD). It is a chronic condition that may recur at various times over a lifetime. It usually involves the small intestine, most often the lower part called the ileum. However, inflammation may also affect the entire digestive tract, including the mouth, esophagus, stomach, duodenum, appendix, or anus. Click Image to Enlarge What causes Crohn's disease? There are many theories regarding Crohn's disease, ...

Diarrhea in Children What is diarrhea? Diarrhea is defined either as watery stool or increased frequency (or both) when compared to a normal amount. It is a common problem that may last a few days and disappear on its own. Diarrhea may be: acute (short-term, lasting less than two weeks), which is usually related to bacterial or viral infections. chronic (long-term, lasting longer than two weeks), which is usually related to functional disorders, such as irritable bowel syndrome, or may be due to disease...

Digestive Diagnostic Procedures for Children In order to reach a diagnosis for digestive and liver problems, a thorough and accurate medical history must be taken by the physician, noting the symptoms your child has experienced and any other pertinent information. A physical examination is also done to help assess the problem more completely. Some patients need to undergo a more extensive diagnostic evaluation, which may include laboratory tests, imaging tests, or endoscopic procedures. These tests may ...

Dysphagia What is dysphagia? Dysphagia is a term that means "difficulty swallowing." It is the inability of food or liquids to pass easily from the mouth, into the throat, and down into the esophagus to the stomach during the process of swallowing. What causes dysphagia? To understand dysphagia, we must first understand how we swallow. Swallowing involves three stages. These three stages are controlled by nerves that connect the digestive tract to the brain. oral preparation stage Food is chewed and moi...

Encopresis What is encopresis? Encopresis is a problem that children four years old or older can develop due to chronic (long-term) constipation. With constipation, children have fewer bowel movements than normal, and the bowel movements they do have can be hard, dry, and difficult to pass. Once a child becomes constipated, a vicious cycle can develop. The child may avoid using the bathroom to avoid discomfort. Stool can become impacted (packed into the rectum and large intestine) and unable to move for...

Food Allergies in Children What is food allergy? A food allergy is an abnormal response of the body to a certain food. It is important to know that this is different than a food intolerance, which does not affect the immune system, although some of the same symptoms may be present. What causes food allergy? Before having a food allergy reaction, a sensitive child must have been exposed to the food at least once before, or could also be sensitized through breast milk. It is the second time your child eat...

Gastroesophageal Reflux Disease (GERD) / Heartburn in Children What is GERD? Gastroesophageal reflux disease (GERD) is a digestive disorder that is caused by gastric acid flowing from the stomach into the esophagus. Gastroesophageal refers to the stomach and esophagus, and reflux means to flow back or return. Gastroesophageal reflux (GER) is the return of acidic stomach juices, or food and fluids, back up into the esophagus. GER is very common in infants, though it can occur at any age. It is the most c...

Glossary - Digestive and Liver Disorders | A | | B | | C | | D | | E | | F | | G | | H | | I | | J | | K | | L | | M | | N | | O | | P | | Q | | R | | S | | T | | U | | V | | W | | X | | Y | | Z | A [back to top] abdominal ultrasound - a diagnostic imaging technique which creates images from the rebound of high-frequency sound waves in the internal organs. abdominal x-ray - a simple study that will give the physician an idea of how the internal organs look. absorption - the passage of nutrients in food ...

Helicobacter Pylori in Children Click Image to Enlarge What is Helicobacter pylori ( H. pylori )? H. pylori is a spiral-shaped bacterium found in the stomach, which (along with acid secretion) damages stomach and duodenal tissue, causing inflammation and peptic ulcers. According to the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), H. pylori causes most all of the ulcers. The NIDDK estimates that about 20 percent of people under 40 years old and half of those over 60 have it. ...

Hirschsprung's Disease What is Hirschsprung's disease? Hirschsprung's disease occurs when some of the nerve cells that are normally present in the intestine do not form properly while a baby is developing during pregnancy. As food is digested, muscles move food forward through the intestines in a movement called peristalsis. When we eat, nerve cells that are present in the wall of the intestines receive signals from the brain telling the intestinal muscles to move food forward. In children with Hirschsp...

Topic Index The Digestive System - An Overview Diagnostic Procedures Problems in Prenatal Development of the Digestive Tract Common Children's Digestive Problems Problems Affecting the Upper Digestive Tract Problems Affecting the Lower Digestive Tract Inflammatory and Infectious Disorders Liver Disorders Glossary Digestive disorders affecting infants and children range from simple problems that most children experience, such as vomiting or diarrhea, to more serious problems such as the birth defect trac...

How the Liver Works Anatomy of the liver: The liver is located in the upper right-hand portion of the abdominal cavity, beneath the diaphragm and on top of the stomach, right kidney, and intestines. The liver, a dark reddish-brown organ that weighs about 3 pounds, has multiple functions. Click Image to Enlarge There are two distinct sources that supply blood to the liver: Oxygenated blood flows in from the hepatic artery. Nutrient-rich blood flows in from the hepatic portal vein. The liver holds about 1...

Inflammatory and Infectious Digestive Disorders There are many types of inflammations and infectious disorders affecting the digestive system that require clinical care by a physician or other healthcare professional. Listed in the directory below are some, for which we have provided a brief overview. Appendicitis Stomach and Duodenal Ulcers (Peptic Ulcers) Helicobacter Pylori Crohn's Disease Ulcerative Colitis Necrotizing Enterocolitis Viruses, Bacteria, and Intestinal Parasites in the Digestive Tract

Inguinal and Umbilical Hernia What is a hernia? A hernia occurs when a section of intestine protrudes through a weakness in the abdominal muscles. A soft bulge is seen underneath the skin where the hernia has occurred. In children, a hernia usually occurs in one of two places: around the belly-button in the groin area A hernia that occurs in the belly-button area is called an umbilical hernia . A hernia that occurs in the groin area is called an inguinal hernia . What causes a hernia? A hernia can devel...

Intestinal Malrotation and Volvulus What is intestinal malrotation? Intestinal malrotation is a birth defect involving a malformation of the intestinal tract. Intestinal malrotation is an abnormality that occurs while a fetus is forming in its mother's uterus. Click Image to Enlarge As a fetus is growing in its mother's uterus before birth, different organ systems are developing and maturing. The digestive tract starts off as a straight tube from the stomach to the rectum. Initially, it is located in th...

Intussusception What is intussusception? Intussusception is the most common cause of intestinal obstruction in children between ages three months and three years old. Intussusception occurs when a portion of the intestine folds like a telescope, with one segment slipping inside another segment. It can occur in the colon, the small bowel, or between the small bowel and colon. The result can be a blocked small bowel or colon. This causes an obstruction, preventing the passage of food that is being digeste...

Irritable Bowel Syndrome What is irritable bowel syndrome? Irritable bowel syndrome is one of the manifestations of functional abdominal pain. Functional means that there is no organic disease. Functional abdominal pain describes a constellation of symptoms as a result of intestinal motility disorders. Symptoms may include: flatulence bloating diarrhea constipation urgency with defecation incomplete sensation of defecation passage of mucus in the stool What causes irritable bowel syndrome? The digestion...

Lactose Intolerance in Children What is lactose intolerance? Lactose intolerance is a condition caused by a lack of an enzyme called lactase. Inadequate amounts of lactase cause the body to be unable to digest lactose, a sugar found in milk and milk products. Lactase is normally produced by cells lining the small intestine where it breaks lactose down into a form that can be absorbed by the blood. A lack of lactase can cause uncomfortable symptoms for some people. Those who do exhibit the symptoms are s...

Liver Disorders There are many different disorders of the liver that require clinical care by a physician or other healthcare professional. Listed in the directory below are some, for which we have provided a brief overview. How the Liver Works Common Characteristics of Liver Disease Biliary Atresia Hepatitis Liver Transplantation

Liver Transplantation in Children What is a liver transplant? A liver transplant is a surgical procedure performed to replace a diseased liver with a healthy liver from another person. The liver may come from a deceased (cadaveric) organ donor or from a living donor. Family members or individuals who are unrelated but make a good match may be able to donate a portion of their liver. This type of transplant is called a living transplant (living donor). Individuals who donate a portion of their liver can ...

Meckel's Diverticulum What is Meckel's diverticulum? Meckel's diverticulum is a small pouch in the wall of the intestine, near the junction of the small and large intestines. The pouch is a remnant of tissue from the prenatal development of the digestive system. It is not made of the same type of tissue as the small intestine, but, instead, is made of the type of tissue found in the stomach or the pancreas. The tissue in Meckel's diverticulum produces acid, just as the tissue of the stomach does. The in...

Omphalocele What is an omphalocele? An omphalocele is a birth defect, which is an abnormality that occurs before birth as a fetus is forming in its mother's uterus. Some of the abdominal organs protrude through an opening in the abdominal muscles in the area of the umbilical cord. A translucent membrane covers the protruding organs. The omphalocele may be small, with only a portion of the intestine protruding outside the abdominal cavity, or large, with most of the abdominal organs (including intestine,...

Online Resources - Digestive and Liver Disorders This Web was compiled from a variety of sources including the online resources listed below, but is not intended to substitute or replace the professional medical advice you receive from your child's physician. The content provided here is for informational purposes only, and was not designed to diagnose or treat a health problem or disease. Please consult your child's physician with any questions or concerns you may have regarding your condition. This pa...

Problems Affecting the Lower Digestive Tract There are many problems that may affect the lower digestive tract that require clinical care by a physician or other healthcare professional. Listed in the directory below are some, for which we have provided a brief overview. Constipation Encopresis Hirschsprung's Disease Irritable Bowel Syndrome Intussusception Intestinal Malrotation/Volvulus Pyloric Stenosis Meckel's Diverticulum

Problems Affecting the Upper Digestive Tract There are many problems that may affect the upper digestive tract that require clinical care by a physician or other healthcare professional. Listed in the directory below are some, for which we have provided a brief overview. Dysphagia Gastroesophageal Reflux Disease (GERD)/Heartburn

Problems in Prenatal Development of the Digestive Tract There are many problems that may occur during the prenatal development of the digestive tract that require clinical care by a physician or other healthcare professional. Listed in the directory below are some, for which we have provided a brief overview. Tracheoesophageal Fistula and Esophageal Atresia Diaphragmatic Hernia Omphalocele Inguinal and Umbilical Hernia Anorectal Malformations

Stomach and Duodenal Ulcers (Peptic Ulcers) in Children Click Image to Enlarge What is a stomach or duodenal ulcer? About one in 10 Americans develops at least one ulcer during his or her lifetime. An ulcer is an open sore, or lesion, usually found on the skin or mucous membrane areas of the body. An ulcer in the lining of the stomach or duodenum, where hydrochloric acid and pepsin are present, is referred to as a peptic ulcer. When the ulcer is in the stomach, it is called a gastric ulcer. When the ulc...

Topic Index - Digestive and Liver Disorders Digestive & Liver Disorders Home The Digestive System - An Overview Diagnostic Procedures Problems in Prenatal Development of the Digestive Tract Tracheoesophageal Fistula and Esophageal Atresia Diaphragmatic Hernia Omphalocele Inguinal and Umbilical Hernia Anorectal Malformations Common Children's Digestive Problems Colic Diarrhea Food Allergies Lactose Intolerance Problems Affecting the Upper Digestive Tract Dysphagia Gastroesophageal Reflux Disease (GER...

Tracheoesophageal Fistula and Esophageal Atresia What is tracheoesophageal fistula? Tracheoesophageal fistula is an abnormal connection in one or more places between the esophagus (the tube that leads from the throat to the stomach) and the trachea (the tube that leads from the throat to the windpipe and lungs). Normally, the esophagus and the trachea are two separate tubes that are not connected. Tracheoesophageal fistula is also known as TE fistula or simply TEF. TE fistula is a birth defect, which is...

Ulcerative Colitis in Children Click Image to Enlarge What is ulcerative colitis? Ulcerative colitis is an inflammatory bowel disease (IBD) in which the inner lining of the large intestine (colon or bowel) and rectum become inflamed. Inflammation usually begins in the rectum and lower (sigmoid) intestine and spreads upward to the entire colon. Ulcerative colitis rarely affects the small intestine except for the lower section, the ileum. The inflammation causes diarrhea, or frequent emptying of the colon...

Viruses, Bacteria, and Parasites in the Digestive Tract What are viruses, bacteria, and parasites? Viruses, bacteria, and parasites are living organisms that are found all around us. They exist in water and soil, on the surfaces of foods that we eat and on surfaces that we touch, such as countertops in the bathroom or kitchen. Some bacteria live in our bodies and do not cause problems. Other kinds of bacteria (as well as parasites and viruses) can make us quite ill if they invade our bodies. Bacteria an...