What Is Bacterial Diarrhea?

Bacterial infectious diarrhea refers to a group of common intestinal infectious diseases caused by various bacteria in a broad sense, with diarrhea as the main manifestation. This article refers to bacterial infectious diarrhea other than cholera, bacillary dysentery, typhoid fever, and paratyphoid fever, which belongs to the Class C infectious diseases specified in the Law of the People's Republic of China on the Prevention and Control of Infectious Diseases. The onset of the disease is global and is usually sporadic and can be epidemic. The clinical manifestations are mainly gastrointestinal symptoms, ranging in severity and self-limitation, but a few can have serious complications and even lead to death.

Basic Information

Visiting department

Gastroenterology

Common locations

Intestine

Common causes

Salmonella, Shigella, Escherichia coli, Campylobacter, Yersinia, Staphylococcus aureus, Vibrio parahaemolyticus, Clostridium difficile and other infections

Common symptoms

Anorexia, nausea, vomiting, bloating, abdominal pain, diarrhea

Causes of bacterial infectious diarrhea

Common bacteria are Salmonella, Shigella, Escherichia coli, Campylobacter, Yersinia, Staphylococcus aureus, Vibrio parahaemolyticus, Clostridium difficile, etc.

Clinical manifestations of bacterial infectious diarrhea

The incubation period is from hours to days and weeks. More acute onset, a few have a slower onset. Clinical manifestations vary, with gastrointestinal symptoms being the most prominent. Appetite, nausea, vomiting, bloating, abdominal pain, diarrhea can be accompanied by acute aftermath, and the number of diarrhea can be as many as ten, twenty, or even countless times a day. , Feces were watery, mucus, pus and blood. Abdominal pain does not usually occur in secretory diarrhea, and abdominal pain often occurs in invasive diarrhea. Often accompanied by chills, fever, fatigue, dizziness and other symptoms, in severe cases, dehydration, electrolyte disturbance, and even shock due to a large loss of water. The course of the disease ranges from a few days to 1 to 2 weeks, often self-limiting, and a few can recur. The clinical types of diarrhea caused by different bacteria are different, and the common types are described below:

Enterohemorrhagic E.coli infection

Acute onset, mild watery diarrhea, typical patients with severe abdominal pain, watery stools, bloody stools a few days later, abdominal pain, diarrhea, low fever or no fever.

2. Yersinia infection

Gastrointestinal inflammation is prominent in infants and children, and enteritis is predominant in adults. Urgent onset, with fever, diarrhea, and abdominal pain as the main manifestations. The heat course is usually 2 to 3 days. Diarrhea is usually 1 to 2 days, and the severe case is 1 to 2 weeks. Abdominal pain is common and can be limited to the right lower abdomen, and can be accompanied by muscle tension and rebound pain.

3. Proteus infection

Under certain conditions, it can cause a variety of infections, such as purulent infections, urinary tract infections, gastroenteritis, endocarditis, and sepsis. The main manifestations are fever, nausea, vomiting, abdominal pain, and diarrhea. The site of abdominal pain is in the upper abdomen and around the umbilicus. Those with mild diarrhea several times a day and severe cases with 20-30 times.

4. Antibiotic-related diarrhea

Most manifested as mild to moderate watery diarrhea, fever, bloating, sporadic pain in the lower abdomen or whole abdomen. Severe cases also see mucus, blood is rare, and severe complications include dehydration, hypoalbuminemia, electrolyte disturbances, intestinal paralysis and bowel perforation.

5. Tourist diarrhea

Generally, the onset of the disease is rapid (hours to days), about 40% of tourists with mild symptoms of diarrhea, severe symptoms of diarrhea, accompanied by abdominal cramps, nausea, vomiting and fever.

6. AIDS-related diarrhea

Diarrhea is often the first symptom of AIDS and the cause of death. Patients are often accompanied by fever, malaise, nausea, vomiting, anorexia, and weight loss. The duration of acute diarrhea usually does not exceed two weeks, and chronic diarrhea usually lasts for weeks or months.

Bacterial infection diarrhea

Peripheral blood routine examination

Generally, the total number of white blood cells is increased or normal, neutrophils are increased, or the nucleus is shifted to the left.

2. Fecal routine

Observe the appearance, amount, consistency of the stool and presence of food residue, mucus, pus and blood. After different bacterial infections, the feces can exhibit characteristics such as watery stools, meaty watery stools, pus and blood stools, bloody stools, and mucus stools. If suspected Vibrio cholerae and Campylobacter infections, apply the fecal suspension drop test method. Vibrio cholerae can show characteristic fish-like movements, and Campylobacter can see spiral movement bacteria with aggressive movements.

3. Fecal culture

The diagnosis is based on the fact that the general culture has a low positive rate and the methods to increase the positive rate include: taking materials before applying antibiotics; taking mucus pus and blood from fresh feces; keeping samples warm in time for examination; continuous multiple cultures; colonoscopy Take materials; In addition to disulfide and blood agar medium, the appropriate medium and culture conditions should be selected according to the suspected pathogens.

4. Immunological examination

Common methods include latex agglutination test, enzyme-linked immunosorbent assay (ELISA), passive hemagglutination test (PHA), immunofluorescence method (IFA), immunomagnetic bead method, enzyme immunofluorescence method, etc., for bacteria and toxins in feces 2. Detection of specific antigens and antibodies in serum.

5. Nucleic acid detection

Gene probe technology and polymerase chain reaction technology can detect pathogen-specific gene fragments. The method is simple, rapid and sensitive. DNA fingerprinting, gel electrophoresis, etc. can track the spread of infections in hospitals, which is conducive to epidemiological investigations.

Diagnosis of bacterial infectious diarrhea

According to the epidemiological data, including the season, region, age, history of unclean diet, history of collective illness, history of animal exposure, history of exposure to water and antibiotics, history of surgery, combined with symptoms, signs, course of disease and number of diarrhea, Considering the possible pathogens such as traits, the diagnosis depends on the isolation, culture and specific examination of fecal pathogens.

Bacterial infection diarrhea treatment

Symptomatic treatment

If diarrhea is accompanied by vomiting or severe abdominal pain, atropine drugs can be given, but opioids should be used with caution or disabled, because they can strongly inhibit intestinal peristalsis, make the toxin easily absorbed, and aggravate poisoning or induce toxic megacolon. There are also proposals to use intestinal mucosal protective agents such as Smecta, which can adsorb pathogenic bacteria and toxins, and can strengthen the mucus barrier through the interaction with intestinal mucus molecules to prevent the invasion of pathogenic bacteria. In addition, berberine (berberine) has good astringency and slight bacteriostatic effect, and has a certain effect on bacterial diarrhea.

Fluid therapy

(1) Oral rehydration therapy (ORT) is suitable for the adjuvant treatment of mild, moderate dehydration and severe dehydration in acute diarrhea. The dosage and frequency should be controlled according to the number of diarrhea and the degree of dehydration.

(2) Intravenous rehydration therapy is suitable for patients with severe diarrhea with dehydration, electrolyte disturbance, acidosis or shock. We recommend lactating Ringer's solution for fluid replacement. Initially, rapid fluid replacement should be followed. Follow the basic principles of fluid replacement. Those with secondary acidosis should be given intravenously % Sodium bicarbonate or 11.2% sodium lactate, the amount can be given in half according to the blood gas analysis results, and then decided according to the specific situation, pay attention to potassium and calcium supplementation. When the patient's dehydration corrected and vomiting improved, he changed to oral rehydration.

3. Antibiotic treatment

Different antibiotics are used for different pathogens. Mild patients with Yersinia infection are mostly self-limiting and do not need to be treated with antibiotics. Those with severe or concurrent sepsis are selected according to drug sensitivity experiments. The course of treatment is 2 to 3 days. Sensitive to glycoside antibiotics, chloramphenicol, sulfonamides and fluoroquinolones. Intestinal invasive, pathogenic or enterotoxigenic Escherichia coli caused diarrhea can generally be taken orally with fluoroquinolones for 3 to 5 days.

Discontinuation of antibiotics in mild patients with C. difficile-associated diarrhea can restore normal flora and relieve symptoms. If diarrhea persists after antibiotics are discontinued, antibiotics directed against C. difficile should be considered. Severe patients should be treated with effective antibiotics immediately.

In the treatment of AIDS-related diarrhea, antibacterial drugs such as cephalosporins and fluoroquinolones should be applied in a sufficient amount in time.

4. Microecological therapy

Because the cause of bacterial diarrhea is the invasion of exogenous bacteria, the translocation of normal bacteria, and the imbalance of ratios, all of which lead to the destruction of the normal intestinal flora and the imbalance of the intestinal microecology. Micro-ecological therapy is recommended in order to restore the normal intestinal flora, rebuild the intestinal biological barrier, and antagonize the colonization of pathogenic bacteria, which is beneficial to the control of diarrhea. Commonly used preparations are probiotics and prebiotics, such as bifidobacteria, lactic acid bacteria and so on. Prebiotics include lactulose, fructooligosaccharides, inulin, and the like. However, it should be noted that oral oral bacterial preparations should be separated from antibiotics for about 2 hours to prevent the killing of live bacteria and affect the efficacy.