close
Bacterial gastroenteritis

Bacterial gastroenteritis

Bacterial gastroenteritis occurs when there is bacterial infection of your stomach and intestines. Gastroenteritis is an inflammation of the gastrointestinal tract (the pathway responsible for digestion that includes the mouth, esophagus, stomach, and intestines). Gastroenteritis is also sometimes referred to as “stomach flu,” even though it may not be related to influenza. Bacterial gastroenteritis can affect one person or a group of people who all ate the same food. Bacterial gastroenteritis is commonly called food poisoning. It often occurs after eating at picnics, school cafeterias, large social gatherings, or restaurants. However, the most common cause of acute gastroenteritis are viruses (norovirus, rotavirus, adenovirus, and others).

Medically, gastroenteritis is defined as a diarrheal disease, in other words, an increase in bowel movement frequency with or without vomiting, fever, and abdominal pain 1. An increase in bowel movement frequency is defined by three or more watery or loose bowel movements in 24 hours or at least 200 grams of stool per day. Gastroenteritis is classified in many ways, but according to the duration of symptoms, it is described as acute, persistent, chronic, or recurrent.

  • Acute: 14 days or fewer than 14 days in duration.
  • Persistent: More than 14 but fewer than 30 days in duration.
  • Chronic: More than 30 days in duration.
  • Recurrent: Diarrhea that recurs after 7 days without diarrhea 2.

The diagnosis and management of bacterial gastroenteritis is best done with a multidisciplinary team that includes the primary care provider, nurse practitioner, infectious disease consultant and the emergency department physician. The key aim of treatment is to prevent dehydration and electrolyte alterations. The majority can be treated as outpatients but children and the elderly may require admission, depending on their hydration status. Some other post-diarrhea complications include exacerbation of inflammatory bowel disease, septicemia, enteric fever, and Guillain-Barre syndrome, a complication likely after Campylobacter infection. Reactive arthritis may occur, particularly after Shigella, Salmonella, Campylobacter, or Yersinia 3. With proper treatment the outcomes are excellent but any delay in treatment can lead to significant morbidity and mortality 4.

When to contact a medical professional

See your doctor if you have:

  • Blood or pus in your stools, or your stool is black
  • Diarrhea with a fever above 101°F (38.33°C) or 100.4°F (38°C) in children
  • Recently traveled to a foreign country and developed diarrhea
  • Stomach pain that does not go away after a bowel movement
  • Symptoms of dehydration (thirst, dizziness, lightheadedness)

Also see your doctor if:

  • The diarrhea gets worse or does not get better in 2 days for an infant or child, or 5 days for adults
  • A child over 3 months old has been vomiting for more than 12 hours; in younger babies, call as soon as vomiting or diarrhea begins

Bacterial gastroenteritis causes

Bacterial gastroenteritis can affect one person or a group of people who all ate the same food. Bacterial gastroenteritis is commonly called food poisoning. It often occurs after eating at picnics, school cafeterias, large social gatherings, or restaurants.

Your food may get infected in many ways:

  • Meat or poultry may come into contact with bacteria when the animal is processed.
  • Water that is used during growing or shipping may contain animal or human waste.
  • Improper food handling or preparation may occur in grocery stores, restaurants, or homes.

Food poisoning often occurs from eating or drinking:

  • Food prepared by someone who did not wash their hands properly
  • Food prepared using unclean cooking utensils, cutting boards, or other tools
  • Dairy products or food containing mayonnaise (such as coleslaw or potato salad) that have been out of the refrigerator too long
  • Frozen or refrigerated foods that are not stored at the proper temperature or are not reheated properly
  • Raw shellfish such as oysters or clams
  • Raw fruits or vegetables that have not been washed well
  • Raw vegetable or fruit juices and dairy products (look for the word “pasteurized” to make sure the food is safe to eat or drink)
  • Undercooked meats or eggs
  • Water from a well or stream, or city or town water that has not been treated

Many different types of bacteria can cause bacterial gastroenteritis, including:

  • Campylobacter jejuni
  • E. coli (Escherichia coli)
  • Salmonella
  • Shigella
  • Staphylococcus
  • Yersinia

Other than norovirus, important causes of watery diarrhea include Clostridium perfringens, and enterotoxigenic Escherichia coli (ETEC). Bacterial causes are more responsible for severe cases of infectious diarrhea than other infectious causes. For example, a single study found that in otherwise healthy adults with diagnosed severe diarrheal illness, defined as greater than or equal to four watery/loose stools per day for 3 or more days, a bacterial pathogen was identified in 87% of cases. Among these severe bacterial causes, nontyphoidal Salmonella and Campylobacter species are the most common causes in the United States. The incidence rate per 100,000 persons in 2016 was estimated by the Centers for Disease Control and Prevention controlled active surveillance program, FoodNet, survey with results as follows:

  • Salmonella – 15.4
  • Campylobacter – 11.8
  • Shigella – 4.6
  • Shiga toxin-producing E. coli – 2.8
  • Vibrio – 0.45
  • Yersinia – 0.42
  • Listeria – 0.26 5

Bacterial gastroenteritis prevention

There are several steps that you can take to reduce your risk of getting gastroenteritis, including:

  • Washing your hands frequently, especially after going to the bathroom and when you are working with food.
  • Cleaning and disinfecting kitchen surfaces, especially when working with raw meat or eggs.
  • Keeping raw meat, eggs, and poultry away from foods that are eaten raw.
  • Drinking bottled water and avoiding ice cubes when traveling, especially in developing countries.

Bacterial gastroenteritis symptoms

Bacterial gastroenteritis symptoms depend on the type of bacteria that caused the sickness. All types of food poisoning cause diarrhea. Other symptoms include:

  • Abdominal cramps
  • Abdominal pain
  • Bloody stools
  • Loss of appetite
  • Nausea
  • Vomiting
  • Fever (suggests an invasive organism as the cause).
  • Poor feeding (in infants)
  • Unintentional weight loss (may be a sign of dehydration)
  • Excessive sweating
  • Clammy skin
  • Muscle pain or joint stiffness
  • Incontinence (loss of stool control)

Because of the symptoms of vomiting and diarrhea, people who have gastroenteritis can become dehydrated quickly. It is very important to watch for signs of dehydration, which include:

  • Extreme thirst
  • Urine that is darker in color, or less in amount
  • Dry skin
  • Dry mouth
  • Sunken cheeks or eyes
  • In infants, dry diapers (for more than 4-6 hours)

Bacterial gastroenteritis complications

Dehydration and depletion of electrolytes are the most common complications above all. Other complications that are common after acute gastroenteritis are the transformation of acute into chronic diarrhea which can lead to lactose intolerance or small-bowel bacterial overgrowth. Some other post-diarrhea complications include exacerbation of inflammatory bowel disease, septicemia, enteric fever, and Guillain-Barre syndrome, a complication likely after Campylobacter infection. Reactive arthritis may occur, particularly after Shigella, Salmonella, Campylobacter, or Yersinia 3.

Bacterial gastroenteritis diagnosis

Your health care provider will examine you for signs of food poisoning. These may include pain in the stomach and signs your body does not have as much water and fluids as it should (dehydration).

Lab tests may be done on the food or a stool sample to find out what germ is causing your symptoms. However, these tests do not always show the cause of the diarrhea.

Stool testing for bacterial pathogens is indicated in the presence of severe illness (e.g., signs of dehydration/hypovolemia, severe abdominal pain, or need for hospitalization) high-risk host features (e.g., pregnant women, age greater than 70 years, immunocompromised state, or other co-morbidities), and other signs and symptoms of inflammatory diarrhea (e.g., mucus or blood in diarrhea, high-grade fever). A routine stool culture can identify three common bacteria: Salmonella, Campylobacter, and Shigella. Suspicion of other bacterial pathogens (e.g., Vibrio, Yersinia, Aeromonas, and Listeria) should warrant specific microbiology and culture analysis. In case of bloody diarrhea, additional testing for Shiga toxin and leukocytes in stool for enterohemorrhagic E. coli (EHEC) should be ordered in addition to stool culture. In case of persistent diarrhea, the practitioner should send stool samples for ova and parasite testing 6.

Bacterial gastroenteritis treatment

You will most likely recover from the most common types of bacterial gastroenteritis in a couple of days. The goal is to make you feel better and avoid dehydration.

Drinking enough fluids and learning what to eat will help ease symptoms. You may need to:

  • Manage the diarrhea
  • Control nausea and vomiting
  • Get plenty of rest

Oral rehydration: Live Lactobacillus GG 7 and heat-killed Lactobacillus LB 8 reduce the duration of diarrhea in children when added to oral rehydration solution

If you have diarrhea and are unable to drink or keep down fluids because of nausea or vomiting, you may need fluids through a vein (IV). Young children may be at extra risk of getting dehydrated.

If you take diuretics (“water pills”), or ACE inhibitors for high blood pressure, talk to your provider. You may need to stop taking these medicines while you have diarrhea. Never stop or change your medicines without first talking to your provider.

Antibiotics are not given very often for most common types of bacterial gastroenteritis. If diarrhea is very severe or you have a weak immune system, antibiotics may be needed.

You can buy medicines at the drugstore that can help stop or slow diarrhea. Do not use these medicines without talking to your provider if you have:

  • Bloody diarrhea
  • Severe diarrhea
  • Fever

Do not give these medicines to children.

Doctors usually do not recommend antidiarrheal medications (such as Loperamide) for gastroenteritis because they tend to prolong infection, especially in children.

Bacterial gastroenteritis antibiotics therapy

Not every patient, even with a known bacterial etiology, should be given antibiotic therapy, especially with Shiga toxin-producing E. coli. Empiric antibiotic therapy with azithromycin or fluoroquinolones can be indicated in severe illness (e.g., greater than 6 stools in a day, fever, need for hospitalization), specific host factors (e.g., age greater than 70 years, immunocompromised host, having co-morbidities), and features suggesting of the invasive organisms (e.g., blood or mucus in stool) but should be discontinued if enterohemorrhagic E. coli (EHEC) is isolated. Tetracyclines have the greatest efficacy for Vibrio. For pregnant patients with the suspicion of Listeria, ampicillin is the drug of choice. For clostridioides difficile infection, discontinuation of the causative antibiotic and antibiotic therapy should be initiated. It should be noted that recent Centers for Disease Control and Prevention guidelines changed in March 2018 and now recommend either oral vancomycin or fidaxomicin for nonsevere over oral metronidazole for severe clostridioides difficile infection. A combination therapy of oral vancomycin with IV metronidazole should be used for fulminant clostridioides difficile infection.

Standard antimicrobial therapies for bacterial gastroenteritis include the following:

  • Aeromonas species: Cefixime and most third- and fourth-generation cephalosporins
  • Bacillus species: None necessary for self-limited gastroenteritis; vancomycin and clindamycin for severe disease
  • Campylobacter species: Erythromycin; therapy started more than 4 days after onset of symptoms appears to produce no clinical benefit
  • Clostridioides difficile (Clostridium difficile): Discontinuance of the potential causative antibiotics; if this is impossible or ineffective, oral metronidazole or (in seriously ill patients who do not respond to metronidazole) vancomycin
  • Clostridium perfringens: None
  • Listeria species: None necessary unless invasive disease occurs; ampicillin and trimethoprim-sulfamethoxazole (TMP-SMX) for invasive disease
  • Plesiomonas species: trimethoprim-sulfamethoxazole or any cephalosporin
  • Vibrio cholerae: Tetracycline; in resistant cases, trimethoprim-sulfamethoxazole, erythromycin, doxycycline, chloramphenicol, or furazolidone
  • Yersinia species: trimethoprim-sulfamethoxazole, fluoroquinolones, or aminoglycosides; reserved for complicated cases
  • E coli: trimethoprim-sulfamethoxazole if diarrhea is moderate or severe; for systemic complications, a parenteral second-generation or third-generation cephalosporin
  • Salmonella species: None necessary for nontyphoid, uncomplicated diarrhea but may be considered for infants younger than 3 months and for high-risk patients (eg, those who are immunocompromised or have sickle cell disease); for drug-sensitive strains, ampicillin or, alternatively, trimethoprim-sulfamethoxazole, fluoroquinolones, or third-generation cephalosporins
  • Shigella species: None necessary for most mild infections; for moderate-to-severe cases, ampicillin for drug-sensitive strains and trimethoprim-sulfamethoxazole for ampicillin-resistant strains or in cases of penicillin allergy; fluoroquinolones may be considered in patients with highly resistant organisms

Bacterial gastroenteritis prognosis

Most people with bacterial gastroenteritis get better in a few days without treatment.

Certain rare types of E-coli can cause:

  • Severe anemia
  • Gastrointestinal bleeding
  • Kidney failure.
References
  1. Sattar SBA, Singh S. Bacterial Gastroenteritis. [Updated 2019 Mar 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2019 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK513295
  2. Hiyoshi H, Tiffany CR, Bronner DN, Bäumler AJ. Typhoidal Salmonella serovars: ecological opportunity and the evolution of a new pathovar. FEMS Microbiol. Rev. 2018 Jul 01;42(4):527-541
  3. Menta PLR, Andrade MER, Leocádio PCL, Fraga JR, Dias MTS, Cara DC, Cardoso VN, Borges LF, Capettini LSA, Aguilar EC, Alvarez-Leite JI. Wheat gluten intake increases the severity of experimental colitis and bacterial translocation by weakening of the proteins of the junctional complex. Br. J. Nutr. 2019 Feb;121(4):361-373.
  4. Mathew S, Smatti MK, Al Ansari K, Nasrallah GK, Al Thani AA, Yassine HM. Mixed Viral-Bacterial Infections and Their Effects on Gut Microbiota and Clinical Illnesses in Children. Sci Rep. 2019 Jan 29;9(1):865.
  5. Kolsin JM, Lopman BA, Payne DC, Wikswo ME, Dunn JR, Halasa NB, Hall AJ. Evaluating Previous Antibiotic Use as a Risk Factor for Acute Gastroenteritis Among Children in Davidson County, Tennessee, 2014-2015. J Pediatric Infect Dis Soc. 2018 Aug 17;7(3):e86-e91
  6. Yin Y, Zhou D. Organoid and Enteroid Modeling of Salmonella Infection. Front Cell Infect Microbiol. 2018;8:102
  7. Guandalini S, Pensabene L, Zikri MA, et al. Lactobacillus GG administered in oral rehydration solution to children with acute diarrhea: a multicenter European trial. J Pediatr Gastroenterol Nutr. 2000 Jan. 30(1):54-60.
  8. Simakachorn N, Pichaipat V, Rithipornpaisarn P, et al. Clinical evaluation of the addition of lyophilized, heat-killed Lactobacillus acidophilus LB to oral rehydration therapy in the treatment of acute diarrhea in children. J Pediatr Gastroenterol Nutr. 2000 Jan. 30(1):68-72.
Health Jade Team

The author Health Jade Team

Health Jade