Anti-sensory agents | Intestinal infectious diseases that need to be vigilant in hot summer—bacillary dysentery

The weather is hot, and people like to eat cold and raw foods and seafood. The probability of eating at food stalls and food stalls increases, which leads to an increased chance of being infected with intestinal infectious pathogens.A person who is usually physically strong may be easily knocked down by diarrhea. This may be bacillary dysentery!

What is bacillary dysentery

Bacillary dysentery is an intestinal infectious disease, referred to as bacillary dysentery.

Bacillary dysentery is mainly transmitted through the digestive tract and is sporadic all year round. It is more common in summer and autumn. It is a common and frequently-occurring disease in my country.Children and young adults are at high risk for bacillary dysentery.

Bacillary dysentery is caused by Shigella, also known as Shigella dysenteriae.Whether Shigella will cause disease after entering the body depends on the number of bacteria, its pathogenicity and the body's resistance.When the body's resistance is reduced, such as colds, excessive fatigue, overeating, and digestive tract diseases, bacterial dysentery can easily be induced even if the amount of infection is small.

The incubation period for bacillary dysentery generally ranges from a few hours to 7 days.According to the length and severity of the condition, it is divided into acute bacillary dysentery and chronic bacillary dysentery.The main symptoms are abdominal pain, diarrhea, mucus, pus and bloody stools, and tenesmus, which may be accompanied by fever and systemic toxemia symptoms. In severe cases, septic shock and/or toxic encephalopathy may occur.

After active treatment, most patients with acute bacillary dysentery can recover within 1-2 weeks.A small number of people cannot be cured after long-term treatment and become chronic bacillary dysentery or bacterial carriers.Patients with chronic bacillary dysentery often have abdominal pain and bloody stools, leading to malnutrition, anemia, and physical decline.If bacteria enter the blood and are not treated in time, sequelae such as aphasia, paralysis, and deafness may be left.There are also some patients who have symptoms of systemic poisoning from the beginning, with poor prognosis and high mortality rate.

Why do you get bacillary dysentery?

The following conditions also increase the chance of Shigella infection:

• Eating spoiled or contaminated food

• Drink raw water

• Not paying attention to food hygiene and not washing hands before eating and after using the toilet

• Decreased self-resistance, such as overwork, cold, etc.

• Living in crowded housing with poor sanitation

• Close contact with bacillary dysentery patients or carriers, sharing tableware, etc.

  
  

What tests can be used to diagnose bacillary dysentery?

Routine blood tests, routine stool tests, and immunological tests in regular hospitals are helpful in diagnosing and identifying bacillary dysentery, and etiological tests can confirm the diagnosis of bacillary dysentery.

• Routine blood tests can initially determine whether the patient has bacterial infection and nutritional status;

• Stool routine can directly observe the shape of the stool and detect the bacteria in the stool;

• Immunological examination and bacterial culture have the advantage of early and rapid diagnosis, but are prone to false positives (the antigens in the stool are likely to cross with Shigella, resulting in false positive results);

• Real-time fluorescence quantitative PCR detection is simple and fast, can improve the sensitivity and specificity of detection, and is suitable for rapid screening of intestinal pathogenic bacteria.Especially for patients with negative Shigella culture, PCR testing is a better way to increase the detection rate of Shigella specimens.

Bacillary dysentery should be distinguished from acute diarrhea caused by other causes, such as amoebic dysentery, Salmonella enteritis, Vibrio parahaemolyticus enteritis, cholera and paracholera, Campylobacter jejuni enteritis, viral enteritis, etc.However, it is difficult to identify based on clinical symptoms alone, and it is necessary to use etiological means to diagnose and treat it as soon as possible.

In addition, various types of bacillary dysentery should be distinguished from similar diseases:

Encyclopedia of Pathogenic Microorganisms

Dysentery bacilli is a Gram-negative bacillus belonging to the genus Shigella of the family Enterobacteriaceae.According to the different antigenic structures, it is divided into four groups: A, B, C, and D, namely Shigella dysenteriae (S. dysenteriae), Shigella flexneri (S. flexneri), Shigella baumannii (S. boydii), and Shigella dysenteriae. Shigella dysenteriae (S. sonnei), and 42 serotypes (including subtypes).In foreign countries, group D has gradually become dominant since the late 1960s. In my country, group B is still the dominant group (accounting for 62.8-77.3%), followed by group D. In recent years, group A has been increasing in some areas.

Shigella dysenteriae has certain resistance to the external environment, among which group D is the strongest, group B is the second, and group A is the weakest.It can be killed by irradiating it with sunlight for 30 minutes, heating to 60℃ for 10 minutes or 100℃ for 1 minute.Very sensitive to acids and general disinfectants.It can survive on vegetables, fruits and contaminated items for 1 to 2 weeks, but can grow for several weeks in dark, humid, and freezing conditions. The length of time it survives in feces is related to temperature, bacteria in feces, etc.

Various types of Shigella dysenteriae release endotoxin (lipopolysaccharide) after death and lysis. Recent studies have proven that group A type I and some type II, group B 2a and individual group D can produce exotoxins. The exotoxins are neurotoxins, cytotoxins and intestinal toxins. Toxin effect.All participate in pathogenic effects.In particular, exotoxins are highly toxic and can aggravate inflammatory changes in the intestinal mucosa and extraintestinal lesions.

Shigella dysenteriae develops resistance to anti-drugs, and domestic and foreign studies in recent years have shown that its resistance is becoming increasingly serious.The development of drug resistance is related to chromosomal gene mutations and the continuous transmission of R plasmids (also known as R factors) between species of the same genus and between species of different genus.R plasmid is a type of plasmid, which is an extrachromosomal material composed of double-stranded circular DNA molecules. It can self-replicate and carry certain genetic information.If integrated with the bacterial chromosome, it will replicate synchronously with the chromosome.R plasmid is transmitted between bacterial cells mainly through three pathways: conjugation, conduction, and transformation, among which conjugation transmission is an important method.The R plasmid causes bacteria to produce specific enzymes, which can render antibacterial drugs ineffective. When trace inducers (a small amount of antibacterial drugs) are present, a large amount of specific enzymes can be produced, increasing bacterial resistance.For this reason, clinical application of antibiotics must be sufficient, and small or local use of antibacterial drugs must be avoided to prevent the emergence of drug-resistant strains.