What are some Bacterial Diseases?

Diseases in this group are infectious or infectious diseases caused by bacteria. There are two main types of bacteria classification. One is phenotypic classification, which is based on the phenotype of bacteria, biochemical reaction, and serum reaction. The other is classification by nucleic acid research, that is, by analyzing the base composition of bacterial DNA, the size of the genome, and the homology of DNA. The latter taxonomy is very scientific, causing some bacteria to reassign or change names.

Bacterial disease

Diseases in this group are infectious or infectious diseases caused by bacteria. There are two main types of bacteria classification. One is phenotypic classification, which is based on the phenotype of bacteria, biochemical reaction, and serum reaction. The other is classification by nucleic acid research, that is, by analyzing the base composition of bacterial DNA, the size of the genome, and the homology of DNA. The latter taxonomy is very scientific, causing some bacteria to reassign or change names.

Chinese name

Yes, such as Staphylococcus aureus (staphylococcus aureus), Staphylococcus epidermidis (staphylococcus aureus), alpha hemolytic streptococcus, beta hemolytic streptococcus, non-hemolytic streptococcus, pneumococcus, enterococcus Wait. Important Gram-negative aerobic cocci include meningococci, gonococci, and moraxa. Gram-negative aerobic bacteria include Acinetobacter (Acinetobacter anaerobicus, Acinetobacter luffi), Pseudomonas (Pseudomonas aeruginosa and other pseudomonas), Alcaligenes faecalis, Cloth L., Pertussis, Legionella, etc. Gram-negative facultative anaerobic bacteria such as Enterobacteriaceae (E. coli, Citrobacter, Salmonella, Shigella, Klebsiella, Serratia, Proteus, Profil Botrytis, Morganella), Yersinia pestis, and influenza bacilli. Vibrio cholerae, Vibrio cholerae, Vibrio parahaemolyticus, Aeromonas hydrophila and the like belong to the Vibrio family. Gram-positive anaerobic bacteria include pneumococcus and digestive streptococcus; gram-negative anaerobic cocci such as F. cocci, and gram-negative anaerobic bacteria include fragile bacilli and clostridium. Bacteria that form spores include Bacillus anthracis, cereus, tetanus, perfringens, botulinum, clostridium difficile, and the like. Gram-negative bacilli that do not form spores include Listeria monocytogenes, Rhizoctonia rubrum, and the like. In addition, important pathogenic bacteria include diphtheria, tuberculosis, and leprosy. ^[1]

There are various microorganisms on the normal human body surface and the cavity communicating with the outside world, such as the oral cavity, nasopharynx, intestine, reproductive tract, etc. They are beneficial to the human body under normal conditions of human immune function, and are called normal. Flora. Among them are S. aureus, S. epidermidis, Corynebacterium JK, Propionibacterium acnes, and so on. Some people living in the oropharynx include: Staphylococcus, alpha and beta hemolytic streptococci, non-hemolytic streptococcus, pneumococcus, Neisseria, Morakita, Haemophilus, anaerobic, lactic acid Bacillus, Diphtheria, Eubacteria, Clostridium, Bacillus, Candida albicans, etc. People living in the intestine (end of jejunum to colon) include E. coli, Enterobacter aerogenes, Proteus, Pseudomonas aeruginosa, Staphylococcus, Enterococcus, Perfringens, Digestive cocci, Digestive streptococcus, etc. Bacillus (mainly B. fragile), Bifidobacterium, Eubacteria, Clostridium, Candida albicans, etc. Bacteria living in the vagina include: Lactobacillus, Diphtheria, Bacillus, Enterococcus, E. coli, Neisseria, Anaerobic and so on.

When the body's resistance is reduced, or the defense and immune function are reduced due to various reasons (such as old age, diabetes, liver cirrhosis, tumors, hematological diseases, chemotherapy, radiotherapy, immunosuppressants, hormones and antibacterial drugs, etc.), it is normal. Habitats or bacteria with low pathogenicity may invade other parts of the human body and cause infections, which are called opportunistic pathogens (conditional pathogens). These conditional pathogens can be normal human flora or those that are not normally pathogenic in the environment, such as E. coli, Pneumococcus, Pseudomonas aeruginosa, Enterobacter, Serratia, Salmonella Genus, Staphylococcus aureus, Staphylococcus, Enterococcus, Perfringens, Listeria, Nocardia, etc .; Can also be fungi such as Candida, Aspergillus, Cryptococcus neoformans, Mucor . It can also be caused by some viruses or protozoa. ^[2]

Clinically, a bacterium can infect different parts and cause different diseases. For example, Staphylococcus aureus can cause skin and soft tissue infections, and it can also cause pneumonia, osteomyelitis, meningitis, sepsis, or endocarditis, etc .; enterotoxin producing staphylococcus aureus Can cause food poisoning; a special exotoxin (TSST-1) -producing Staphylococcus aureus can cause toxic shock syndrome. In addition, different bacteria can cause similar clinical manifestations. For example, E. coli, pneumococcus, and influenza bacilli can cause pneumonia, meningitis, and sepsis; Staphylococcus aureus, alpha hemolytic and non-hemolytic streptococci, enterococci, Alkali producing bacteria, Pseudomonas aeruginosa, etc. can cause infective endocarditis.

(A) drug sensitivity test refer to clinical microorganisms

(2) Refer to Clinical Microbiology for Combined Drug Sensitivity Test

(3) The principle and method of the serum bactericidaltitre test are the same as the drug sensitivity test of the test tube dilution method. The test was performed with the patient's serum and the patient's own pathogenic bacteria after antibacterial treatment. The maximum dilution that the patient's serum can inhibit the growth of bacteria is the serum bactericidal titer. It is generally believed that a serum bactericidal titer above 1: 8 indicates that the treatment is effective, and that below 1: 4 may cause treatment failure. This test has great reference significance for the prognosis of patients with severe infection (such as infective endocarditis) or granulocytopenia and sepsis. However, pathogens must be obtained for this test.

(4) Bacterial -lactamase activity measurement Many pathogenic bacteria can produce -lactamase, which hydrolyzes the -lactam ring in the structure of penicillin and cephalosporins and loses its antibacterial activity, such as S. aureus, Resistance to cocci and influenzae to penicillin G or ampicillin. Therefore, clinical laboratories perform drug sensitivity tests on the above-mentioned bacteria, while detecting the production of bacterial -lactamase, which has great reference significance for clinical selection of drugs. The measurement methods include iodine method, microbiological method, acidity (pH) method, etc. The cephalosporin (nitrocefin or cefinase paper) method is the most sensitive and reliable, and the results can be obtained within minutes.

(5) Blood concentration monitoring or therapeutic drug monitoring (therapeuticdrug monitoring (TDM)) The strength of the drug effect is directly proportional to the drug concentration in tissues and body fluids, and the latter is in parallel with the blood drug concentration. Therefore, the determination of blood drug concentration can be As an indirect indicator of drug concentration at the infection site. Therapeutic drug monitoring uses advanced and sensitive testing techniques to measure body fluids, especially the concentration of drugs in the blood, to study the relationship between blood concentration and efficacy and toxicity, determine the optimal dose and dosing interval, improve drug efficacy and reduce adverse effects. reaction. In the application of antibacterial drugs, blood concentration monitoring is mainly suitable for drugs with low therapeutic index and high toxicity, such as aminoglycoside antibiotics, vancomycin, or during the application of chloramphenicol by newborns or infants, or with kidneys. Patients with impaired function appear or may develop drug accumulation in the body when applying antibacterial drugs excreted by the kidneys. Sometimes high-dose penicillin treatment is also monitored to prevent "penicillin encephalopathy".

Methods for measuring blood drug concentration include microbiological method, radioimmunoassay method, enzyme immunoassay method, fluorescence immunoassay method, gas chromatography method and high performance liquid chromatography method. The latter types have the advantages of fastness, specificity, and high sensitivity, but also each have certain shortcomings and limitations, which require specialized equipment.

Clinically isolated Staphylococcus aureus and epistaphylococcus were more than 90% resistant to penicillin G. The resistance of Staphylococcus aureus to cephalosporin is also increasing, and the drug resistance rate can reach 20% to 40%. The data of our hospital indicate that the resistance rate of Staphylococcus aureus to commonly used antibiotics such as erythromycin, tetracycline, chloramphenicol, lincomycin, kanamycin and gentamicin is about 70% or more. About 30% of Fuping and compound SMZ resistance patients. Staphylococcus aureus methicillin-resistant strains have an increasing trend in Shanghai. The prevalence rates were 5% and 24% before 1980 and 1986, respectively, but in some hospitals it was as high as 50-60% after the 1990s. Enterococci show high sensitivity to penicillin G, ampicillin, and rifampicin, but most are resistant to other antibiotics. Staphylococcus aureus, Staphylococcus aureus and Enterococcus are extremely sensitive to vancomycin, and few resistant strains.

Among intestinal bacteria, dysentery bacillus has the most significant resistance to antibacterial drugs. In urban hospitals, dysentery bacillus is mostly resistant to sulfa drugs, streptomycin, tetracycline, and chloramphenicol. The resistance rates to ampicillin and carbenicillin are about 40% 80%, have certain sensitivity to compound SMZ. The resistance of N. songi is more severe than that of F. fuciformis, but the resistance to gentamicin and kanamycin is generally below 10%. It is very sensitive to quinolone, such as piperanic acid and norfloxacin.

The resistance to typhoid bacteria has not been serious for many years. The resistance rate to chloramphenicol, ampicillin and SMZ-TMP is less than 10%. However, typhoid outbreaks caused by drug-resistant strains occurred in the provinces of Jiangsu, Zhejiang, Jiangxi, Liaoning, Hubei, and Guizhou in the late 1980s, and bacteria were more than 80% resistant to the above-mentioned antibacterial drugs. Among other Salmonella spp., Salmonella typhimurium is often resistant to many antibiotics such as chloramphenicol, tetracycline, streptomycin, SMZ-TMP, ampicillin, and can cause the spread or epidemic of infection in some provinces and cities; However, some broad-spectrum semi-synthetic penicillins, cephalosporins, and new quinolones have a good effect on them, and the latter, such as ofloxacin and inoxacin, have achieved satisfactory results after application.

Enterobacteriaceae and Pseudomonas aeruginosa have different degrees of resistance to commonly used antibacterials. The resistance to ampicillin and carbenicillin account for about 65% to 100%, 15% to 60%, respectively, and resistance to piperacillin. About 30% of drug users. Among the new cephalosporins (second and third generation), especially cefuroxime in the second-generation cephalosporins, cefotaxime in the third generation, and ceftriaxone ( ceftriaxone, ceftazidime and cefoperazone have strong antibacterial activity against Enterobacteriaceae; the latter two also have strong effects on Pseudomonas aeruginosa, especially ceftazidime, and other Pseudomonas Bacillus and sugar-free fermented Gram-negative bacilli also have good effects. The resistance rate of gram-negative bacilli to gentamicin is about 20% to 40% (Pseudomonas aeruginosa 40% to 50% or more); the bacteria is resistant to gentamicin, tobramycin, and sisomicin. ), Dibekacin (didekacin, dibekacin, DKB) have a large degree of cross-resistance, but the resistance rate to amikacin (amikacin) is mostly between 10% to 20% .

Drugs for the treatment of bacterial diseases include antibiotics and chemically synthesized drugs. Among them, penicillin G, procaine penicillin and penicillin V, and macrolides (erythromycin, medicamycin, acetyl) Spiromycin, leukomycin, clarithromycin, azithromycin, etc., the latter two also have a good effect on various pathogenic microorganisms such as Legionella, Mycobacterium, Mycoplasma, Chlamydia), Lin Ke (and Klin ) Mycin, vancomycin, and compound sulfa drugs (Xinomethine and trimethoprim mixture SMZ-TMP, sulfadiazine and trimethoprim mixture SD-TMP). Antibiotics that act on drug-resistant Staphylococcus aureus are: those who act on penicillin-producing Staphylococcus aureus, such as oxacillin, cloxacillin, ceftiophene, cefazolin, lincomycin, clindamycin, aminosugar Glycosides, fluoroquinolones, rifampicin, fosfomycin, etc .; those who act on methicillin-resistant Staphylococcus are vancomycin, rifampicin, compound neonomine, netilmicin, etc.

The antibacterial drugs mainly acting on Gram-negative bacilli are aminoglycosides (kanamycin, gentamicin, amikacin, etc.), semi-synthetic penicillins (ampicillin, amoxicillin, carbenicillin, piperazine Lacilin, etc.), second-generation cephalosporins such as cefuroxime, third-generation cephalosporins (cefotaxime, ceftriaxone, ceftazidime, cefoperazone, etc.) and fluoroquinolones (ciprofloxacin, ofloxacin Shaxing, etc.). Acting on Pseudomonas aeruginosa and other pseudomonas are aminoglycosides, semi-synthetic penicillins (carbenicillin, piperacillin, aloxicillin, etc.), ceftazidime, cefoperazone, aztreonam, Amipenem (imipenem, which is used clinically for its mixture with cilastatin, called tienam), and fluoroquinolones.

Drugs acting on anaerobic bacteria include metronidazole, clindamycin, penicillin G (ineffective against bacillus), chloramphenicol, piperacillin, tienam, and the like.

The main anti-tuberculosis drugs are streptomycin, rifampicin, isoniazid, p-salicylic acid, ethambutol, cycloserine, pyrazinamide, ethionamide or propyl isoniazid.

Koi breeding bacterial diseases, such as bacterial hemorrhagic disease, rotten mumps, enteritis, red skin disease, vertical scale disease, printing disease, white skin disease and so on. All pathogens have one thing in common: they are all conditional pathogens.

Causes of bacterial diseases

Only when the breeding density is too high, improper management causes deterioration of the water body, fish body injury, and immunity decline, etc., pathogenic bacteria multiply invade the fish body and become ill. Therefore, in the prevention of bacterial diseases, disinfectants should be used to disinfect water bodies, and then beneficial microbial preparations should be used to maintain a good water quality environment. At the same time, a series of comprehensive methods such as the use of biological enzymes and polysaccharide active additives to improve the fish's autoimmunity.

Prevention and treatment of bacterial diseases

The first aspect is the regulation and control of the water environment. The beneficial microorganisms are used to inhibit the growth of harmful bacteria. Effective control of some conditional pathogens is provided to provide a good environment for the growth and development of koi carp breeding.

The second aspect is to improve the physique of koi by feeding nutrition and health care agents, so that it can have a stronger ability to deteriorate the environment ^[1] . The third aspect is the disinfection and sterilization of water bodies to reduce the harmful bacteria and toxic substances present in the water.

One last point: when the condition worsens and does not eat, injections are also a good way to control bacteria.