Treatment of Urinary Tract Infection Can Not Only Depend on the Results of Drug Sensitivity Tests_NGU_Information Center_Wuhan Dr.lees TCM Clinic

Treatment of Urinary Tract Infection Can Not Only Depend on the Results of Drug Sensitivity Tests

Urinary tract infection is a common infectious disease in the clinic. The correct choice of antibiotics is directly related to the success of treatment.

The 2015 edition of Guidelines for Clinical Application of Antimicrobial Drugs points out that the selection of antimicrobial drugs should be based on the types of pathogens and the susceptibility of pathogens to antimicrobial drugs. That is, before drug treatment, qualified urine samples should be retained for drug sensitivity tests in order to adjust the drug treatment program.

But in the clinic, after the results of drug sensitivity came out, doctors clearly chose antibiotics sensitive to pathogenic bacteria of urinary tract infection for treatment, but why sometimes the clinical effect is not good?

Pharmacodynamically speaking, the formulation of the antimicrobial drug treatment programs should first select the drug sensitive to pathogenic bacteria in order to eliminate pathogenic bacteria. But in addition, the pharmacokinetics of antibiotics should also be considered, that is, whether the drug can reach the infection focus, whether enough concentration can be reached at the infection site to kill the pathogens.

Therefore, the choice of antibiotics should be based on the pharmacokinetic characteristics of different drugs and the sites of infections.

Infection of lower urinary tract

For lower urinary tract infections, antibiotics that can reach the effective drug concentration in urine should be selected. Otherwise, even if the drug sensitivity test in vitro shows that they are sensitive, the concentration of drugs in urine is insufficient, and the pathogens in urine can not be effectively eliminated.

For example, fusidic acid has good antimicrobial activity against Staphylococcus and has a high concentration in tissues with abundant blood supply and even less vascular distribution, all exceeding its minimum antimicrobial concentration against Staphylococcus. However, fusidic acid is mainly metabolized in the liver, excreted by bile rather than the kidney. Therefore, fusidic acid is not a good choice to treat urinary tract infection.

For another example, urinary tract infection caused by Escherichia coli, levofloxacin and moxifloxacin are sensitive, but only about 20% of moxifloxacin is excreted by the kidney in its original form, while about 87% of levofloxacin is detected in urine within 48 hours. Therefore, levofloxacin can be used in the treatment of urinary tract infection, but not moxifloxacin. According to ABX guidelines, moxifloxacin is not suitable for the treatment of complicated urinary tract infections due to its low concentration in urine.

For fungal infections, most fungi isolated from urine are usually sensitive to voriconazole, caspofungin, and micafungin, but because of the low concentration of these drugs in urine, they can not be used to treat fungal urinary tract infections.

Upper urinary tract infection

For patients with upper urinary tract infections, because bloodstream infections cannot be excluded, the selected antibiotics need not only a high concentration in urine but also a high concentration in blood.

Drugs such as furantoin and fosfomycin tromethamine have high concentrations in urine. But its blood concentration is low, so it can only be used for the treatment of lower urinary tract infection, but not for the treatment of upper urinary tract infection. The blood and urine concentrations of levofloxacin and beta-lactam antibiotics are high, which can be used to treat both lower urinary tract infections and upper urinary tract infections.

To sum up, before using antibiotics to treat urinary tract infections, qualified urine samples should be collected in time for pathogenic culture and drug susceptibility test. When selecting antibiotics for drug susceptibility tests, not only pharmacodynamics but also pharmacokinetics of drugs should be taken into account. A reasonable dosage regimen can achieve a good therapeutic effect.

However, patients also need to understand that although antibiotics have a rapid effect, they have great side effects. Long-term use of antibiotics is prone to drug resistance, which will make future treatment more difficult, and patients should follow the doctor's advice rather than abuse it.

In fact, patients choose Diuretic and Anti-inflammatory Pill and other natural medicines without side effects, it will achieve good results, because it is made of a variety of natural herbs, so you can take it for long-term use.