Campylobacter infection

　　It is believed that there are 3 species of Campylobacter that are pathogenic to humans. Campylobacter fetus can typically cause adult bacteremia, which often occurs in patients with recurrent diseases such as diabetes, liver cirrhosis, or malignant tumors. These bacteria can also cause recurrent infections, which are difficult to treat if the patient's immunoglobulins are defective. Campylobacter jejuni can cause meningitis in infants, while Campylobacter jejuni and Campylobacter coli can cause diarrhea in people of any age. Campylobacter is a common bacterial pathogen that can be isolated, with more than 90% of patients with infectious diarrhea being able to isolate Campylobacter jejuni. Contact with wild or domestic infected animals, consumption of contaminated food (especially undercooked poultry), and water can cause outbreaks, but the source of transmission in sporadic cases is often unclear. Outbreaks of Campylobacter jejuni diarrhea in summer are associated with the occurrence of Guillain-Barré syndrome (up to 30% of cases) afterwards.

　　The local complications of Campylobacter infection are caused by the direct spread of the bacteria in the gastrointestinal tract, including cholecystitis, pancreatitis, peritonitis, and massive gastrointestinal bleeding. Extraintestinal manifestations of Campylobacter jejuni infection are very rare, including encephalitis, endocarditis, septic arthritis, osteomyelitis, and neonatal sepsis. Less than 1% of patients with Campylobacter enteritis may develop bacteremia, which is most likely to occur in patients with weakened immune function, children, and the elderly. Patients with Campylobacter jejuni enteritis with weakened immune function often experience transient bacteremia, but it is often undetectable due to the rapid clearance of most strains by the normal human defense mechanism, as well as the fact that acute gastroenteritis patients do not undergo routine blood cultures. The mortality rate of Campylobacter jejuni infection is 0.05/1000. Overall, the complications of Campylobacter infection are rare, and most do not require antibiotic treatment.

　　The most serious complication of Campylobacter infection is Guillain-Barré syndrome (GBS), an acute demyelinating disease of the peripheral nervous system, with an annual incidence rate of 1~2/100,000 in the United States. Infections with certain Campylobacter serotypes carry a higher risk of GBS. In the United States, the most common is Penner serotype O∶19; in South Africa, the most common is Penner serotype O∶41.

　　The most common manifestation is enteritis, similar to Salmonella and Shigella infections. Enteritis can occur in people of all ages, but 1 to 5 years old is the peak age of onset. Diarrhea is watery, sometimes bloody. White blood cells can be seen in fecal smears after staining. Although abdominal pain and liver enlargement are also common, persistent fever (body temperature 38~40℃) after recurrence or intermittent attacks is the only constant symptom of systemic Campylobacter infection. This infection can also manifest as subacute bacterial endocarditis, septic arthritis, meningitis, or asymptomatic fever of unknown origin (FUO).

　　Microbiological examination is necessary for diagnosis, especially to differentiate from ulcerative colitis. Standard culture media can isolate Campylobacter from blood and various body fluids, but selective media are required if isolating from fecal specimens: Skirrow medium containing 7% dissolved horse serum, vancomycin, polymyxin B, and trimethoprim (TMP).

      1:. Adopt proper food handling techniques, especially pay attention to cooking various poultry or other animal-derived foods thoroughly, do not drink untreated water (rivers, lakes, ponds, etc.), and do not drink unpasteurized milk and dairy products.

　　2. Food handlers should maintain hygiene in the kitchen. Most infected individuals can return to work after the stool forms, but they should wash their hands, especially after defecation. Hands should be thoroughly washed before preparing food. Hands should be washed after handling pet feces. Children should not touch animal feces.

　　3. Campylobacter jejuni can spread through drinking water in chicken flocks, so humans can be infected indirectly after chickens are infected. Therefore, clean drinking water that has been chlorinated should be provided to the chicken flock to effectively prevent Campylobacter jejuni infection in poultry.

　　Firstly, routine examination of feces

　　It can be watery stool or mucous stool, and microscopic examination shows a small number of leukocytes and erythrocytes, pus cells, etc. The blood routine shows an increase in the total number of cells and a mild increase in neutrophils.

　　Secondly, pathogen examination:

　　1. Direct examination of fecal smears stained with Gram stain or Wright stain shows slender S-shaped, spiral, comma, or seagull spread-shaped bacilli under a microscope. Fecal suspension and dark-field microscopy can also be used to observe the motility of bacteria.

　　2. Bacterial culture involves inoculating feces onto selective culture media and culturing in a microaerobic environment at 42°C to obtain pathogenic bacteria.

　　3. Serological examination

　　Serum agglutination test should be used to check for O, H, and k antibodies. A 4-fold or more increase in the antibody titer of the convalescent serum is diagnostic.

　　Vitamin A, Vitamin B, Vitamin C, Vitamin E, folic acid, calcium, iron, zinc, selenium, and other nutrients have immune functions. It is best to choose foods containing a variety of nutrients. There are many foods rich in nutrients, soybeans being the most economical and delicious choice. Soybeans contain a large amount of protein, amino acids, carbohydrates, Vitamin A, Vitamin D, Vitamin B, Vitamin C, as well as calcium, phosphorus, zinc, selenium, and trace elements. Especially soybeans are rich in various unsaturated fatty acids, isoflavones, soy lecithin, saponins, plant hormones, oligosaccharides, and other bioactive factors. The vitamins present in the soy milk after deep processing can participate in the metabolic process of the body, promote growth and the formation of antibodies, increase resistance to diseases, and have detoxifying effects.

　　Western treatment methods for campylobacter infection

　　1. Jejunal campylobacter infection

　　Patients do not need special treatment and can recover. However, if diarrhea persists, patients should drink a large amount of water. Most patients do not need antibiotic treatment. For some patients with relatively severe conditions, doxycycline, tetracycline, fluoroquinolones, chloramphenicol, fosfomycin, aminoglycoside antibiotics, and other antibiotics can be used. The use of antibacterial agents at the early stage of the disease can shorten the duration of symptoms. Whether to use antibacterial agents should be decided by the attending physician based on the condition.

　　2. Campylobacter fetus infection

　　Ampicillin and other sensitive antibiotics can be used, such as gentamicin and other aminoglycoside antibiotics. Central nervous system infections can be treated with ampicillin and/or chloramphenicol, with a course of 2-3 weeks. In medium and severe cases, antibacterial drugs should be added, with erythromycin as the first choice, 1-1.5g per day for adults, taken orally in 3-4 doses. After taking the medicine, symptoms are quickly relieved and the time of excretion of bacteria is shortened. Severe patients can switch to gentamicin treatment.

　　3. Extra-intestinal infection

　　Ciprofloxacin 500mg, oral, three times a day or Azithromycin 500mg/d, oral, the course of treatment should be extended to 2-4 weeks to prevent recurrence.