Antibiotics for urinary tract infections

UTIs are a relatively common condition, which occurs more frequently in women, due to its urogenital configuration. It is estimated that at least one in five women will suffer some type of urinary infection throughout their lives.

Urinary infections take place anywhere in the urinary system. That is, they can be located in the bladder, kidneys, ureters or urethra. But nevertheless, It is estimated that 80% of cases correspond to infections in the lower urinary tract, that is, in the bladder and urethra.

The most common form of urinary tract infection is cystitis in women and prostatitis in men. In older adults, the incidence of the disease is similar in both sexes. Seasonal or geographical factors do not seem to have any influence in these cases.

Urinary tract infections

The agents responsible for urinary tract infections are bacteria. Between 70% and 90% of cases are due to the action of the bacteria Escherichia coli. To a lesser extent, there is presence of bacteria as Proteus mirabilis, Staphylococcus coagulase, Klebsiella pneumoniae Y Enterococcus faecalis.

There are people who have a higher propensity to develop urinary tract infections. Mainly those who suffer from diabetes, immunosuppression or are at an advanced age. There is also an increased risk of infection in those who have a neurogenic bladder, carry a catheter or urinary catheter or have an incomplete emptying of the bladder.

The most common urinary tract infections in men are prostatitis, urethritis, epididymitis and orchitis. In women, cystitis, recurrent or not, and asymptomatic bacteriuria (especially due to pregnancy and / or urination syndrome).

Read also: Why do you have cystitis after having sex?

The use of antibiotics

The usual thing is to go to antibiotics as a first line treatment to fight urinary infections. The most used are those that belong to one of the following groups:

  • The quinolones. They are used in the treatment of low urinary infections. Usually, they are administered first intravenously and then orally, since they have good digestive absorption. They are usable in pregnant women, after the third trimester of pregnancy.
  • The aminoglycosides. They are bactericidal antibiotics, especially used when gram-negative bacilli are the cause of the infection. They are used for short periods, because they have toxic effects.
  • Cephalosporins. The use of first-generation cephalosporins is not recommended, but only second-generation cephalosporins for mild infections and third-generation cephalosporins for more serious infections.
  • Aminopenicillins / beta-lactamase inhibitors. Especially recommended for minor infections and for pregnant women, since they do not affect the fetus. Many bacteria are resistant to them.
  • Trimethoprim / sulfamethoxazole (TMP / SMX). They are only used if the bacteria causing the infection have been specifically identified and it has been established that they are sensitive to this medicine. Otherwise, it is not advisable.
  • Nitrofurantoin. It is used mainly to prevent the recurrence of infection, but it is not advisable for women in the first trimester of pregnancy.
  • Fosfomycin-tromethammol. It is effective against Gram-positive and Gram-negative bacteria. It has a unique dose and is one of the most used and efficient antibiotic groups.

Maybe you're interested: Broad-spectrum antibiotics: functions and resistances

Data to keep in mind

The treatment with antibiotics is done taking into account what is the specific agent that causes urinary tract infections. However, bearing in mind that most cases originate from the Escherichia coli, the indicated thing is to initiate the treatment for this, while the laboratory results are obtained.

Antibiotics, as well as most medications, have side effects. Some of them are immediate and, therefore, appear shortly after ingestion. They usually include fever, nausea, diarrhea, vomiting, headache, rashes, tendon problems, and nerve damage.

Other side effects may appear in the medium and long term. This is mainly due to the fact that Most antibiotics affect the vaginal and intestinal flora and they increase the predisposition to bacterial or fungal proliferation in the gynecological and digestive system.

The biggest problem is that the bacteria become resistant to the treatment of antibiotics with relative ease.

Scientists hope that in the next few years, bacteria will develop resistance to antibiotics such as norfloxacin, ciprofloxacin, amoxicillin, ampicillin and others. For now, only fosfomycin-trometamol seems to be sufficiently solid against this effect.