The antimicrobial treatment plan includes the selection of antimicrobial drugs, dose, number of doses, route of administration, duration of treatment, etc., and requires comprehensive consideration of the pathogenic bacteria, the site of infection, the degree of infection and the physiological and pathological conditions of the patient.
The antimicrobial treatment plan includes the selection of antimicrobial drugs, dose, number of doses, route of administration, duration of treatment, etc. The pathogenic bacteria, site of infection, degree of infection and physiological and pathological conditions of the patient should be taken into consideration.
The following points should be noted when formulating the treatment plan in accordance with the Guidelines for the Clinical Application of Antimicrobial Drugs.
I. Variety selection
In principle, the selection of antimicrobial drugs should be based on the type of pathogenic bacteria and their sensitivity to antimicrobial drugs, i.e. the results of bacterial drug sensitivity tests. Therefore, medical institutions with conditions, patients clinically diagnosed with urinary tract infections should start antibacterial therapy before. In case of suspected bloodstream infection, blood specimens should be taken for pathogenic testing to clarify the pathogenic bacteria and drug sensitivity test results as early as possible, and adjust the treatment plan of antibacterial drugs accordingly.
For patients clinically diagnosed with bacterial infection, before the results of the drug sensitivity test of the pathogenic bacteria are known. The possible pathogens can be inferred based on the site of infection (upper or lower urinary tract), onset of disease, site of onset (hospital or community infection), history of previous antimicrobial drug use and response to treatment. And combined with local bacterial resistance surveillance data, empirical treatment with antimicrobial drugs was given first. When the results of pathogenic testing and drug sensitivity tests are known, the drug regimen should be adjusted in conjunction with the previous treatment response: for patients with negative culture results, further treatment measures should be taken based on the effectiveness of empirical treatment and the patient’s condition.
In addition . The selection of antibacterial drugs should be based on the metabolic kinetics of different drugs and combined with the patient’s infection site. For lower urinary tract infections, antimicrobial drugs that can reach effective concentration in urine should be selected; otherwise, even if the in vitro drug sensitivity test shows sensitivity, the concentration of drugs in urine is insufficient to effectively clear the pathogenic bacteria in urine. For example, caspofungin, micafungin and voriconazole, the fungi isolated from urine specimens usually have high sensitivity to these drugs, but because of the low concentration of these drugs in urine, they cannot be used to treat urinary tract infections caused by fungi. In patients with upper urinary tract infections, the selected antimicrobial drugs need to have high concentrations not only in the urine but also in the blood, as bloodstream infections cannot be excluded. Drugs such as furantoin and fosfomycin aminotriol can have high concentrations in the urine. However, their blood concentrations are low, so they are only used to treat lower urinary tract infections. They cannot be used to treat upper urinary tract infections. Levofloxacin and β-lactam antibacterial drugs have high blood and urine concentrations. They can be used to treat both lower urinary tract infections. It can also be used to treat upper urinary tract infection.
Second, the dose of drug administration
Administered according to the therapeutic dose range of various antibacterial drugs. Treatment of upper urinary tract infection. Especially in severe infections, the dose of antibacterial drugs should be larger (therapeutic dose range high limit); while the treatment of simple lower urinary tract infection, because most drugs in the urine drug concentration is much higher than the blood concentration, can be applied to a smaller dose (therapeutic dose range low limit). At the same time, the dose should be adjusted according to the liver and kidney function.
Third, the route of drug administration
For patients with lower urinary tract infection, oral treatment should be given. Choose a variety of orally absorbed antimicrobial drugs, without intravenous or intramuscular injection administration. Only in the following cases can be administered by injection.
1. Patients who cannot take orally or who cannot tolerate oral administration (e.g. those with swallowing difficulties);
2, patients with conditions that may significantly affect the absorption of oral drugs (such as vomiting, severe diarrhea, gastrointestinal lesions or intestinal absorption dysfunction, etc.);
3, the selected drug has a suitable antibacterial spectrum, but no oral dosage form;
4.Patients’ compliance with treatment is poor.
For upper urinary tract infections, the initial treatment is mostly intravenous drugs, which can be changed to oral drugs as appropriate after the condition is stabilized.
Local application of antimicrobial drugs such as prostate injection and bladder instillation of antimicrobial drugs should be avoided as much as possible. Currently, the only bladder instillation with evidence-based medical evidence is bladder instillation of amphotericin B for cystitis caused by fluconazole-resistant Candida.
IV. Frequency of drug administration
In order to ensure the maximum efficacy of the drug in the body and to kill the pathogenic bacteria at the site of infection, the number of doses should be decided according to the pharmacokinetic/pharmacodynamic principles, the severity of the patient’s condition and the hepatic and renal function status. Antimicrobial drugs are divided into time-dependent antimicrobial drugs and concentration-dependent antimicrobial drugs. Time-dependent antibacterial drug concentration reaches a certain level and then increase the concentration of antibacterial effect is not significantly enhanced, and its antibacterial effect is related to the drug concentration higher than the minimum inhibitory concentration (T>MIC), that is, the longer the free drug concentration at the site of infection is higher than the MIC, the better the antibacterial effect. This class of drugs includes p. endocannabinoids and carbapenems, which are mostly administered multiple times a day, except for ceftriaxone and ertapenem, which have long half-lives. Concentration-dependent antibacterial drugs such as quinolones and aminoglycosides, the higher the concentration of the drug, the better the antibacterial effect, so most of these drugs are administered once a day.
V. Course of treatment
The course of antimicrobial drugs varies depending on the infection; for acute simple lower urinary tract infections, the course is basically less than 7 d. However, for upper urinary tract infections, such as acute pyelonephritis, the course is usually 2 weeks. For recurrent urinary tract infections, long-term antibacterial therapy can be administered according to the situation.