Antibiotics For UTIs

Science has not found the ideal antibiotics to treat UTIs. All that are available have short, medium and long term side effects. Likewise, bacteria tend to become resistant to their action.

Urinary tract infections are a relatively common condition, occurring more frequently in women, due to their urogenital configuration. It is estimated that at least one in five women will suffer from some type of urinary infection in her lifetime.

UTIs take place anywhere in the urinary system. That is, they can be located in the bladder, kidneys, ureters or urethra. However, 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 UTI is cystitis in women and prostatitis in men. In older adults, the incidence of the disease is similar in both sexes. Seasonal or geographic factors do not seem to have any influence in these cases.

Urinary infections

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

There are people who are more prone to developing urinary infections. Mainly, those who suffer from diabetes, immunosuppression or are in an advanced age. There is also an increased risk of infection in those who have a neurogenic bladder, have a urinary catheter or catheter, or have incomplete bladder emptying.

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 or voiding syndrome).

The use of antibiotics

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

• Quinolones. They are used in the treatment of lower urinary tract infections. They are generally administered first intravenously and then orally, as they have good digestive absorption. They are usable in pregnant women, after the third trimester of pregnancy.
• Aminoglycosides. They are bactericidal antibiotics, especially used when the cause of the infection is gram-negative bacilli. They are used for short periods of time, because they have toxic effects.
• Cephalosporins. The use of first generation cephalosporins is not recommended, but only second generation for mild infections and third generation for more serious infections.
• Aminopenicillins / beta-lactamase inhibitors. Especially recommended for mild infections and for pregnant women, as 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 has been specifically identified and found to be sensitive to this medicine. Otherwise, it is not advisable.
• Nitrofurantoin. It is used mainly to prevent the recurrence of the infection, but it is not advisable for women in the first trimester of pregnancy.
• Fosfomycin-trometamol. It is effective against gram-positive and gram-negative bacteria. It has a single dose and is one of the most used and efficient groups of antibiotics.

Data to take into account

Antibiotic treatment is done taking into account the specific agent that causes urinary tract infections. However, taking into account that most cases originate from  Escherichia coli , it is indicated to start treatment for it, while the laboratory results are obtained.

Antibiotics, like 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 can appear in the medium and long term. This is mainly due to the fact that most antibiotics affect the vaginal and intestinal flora and increase the predisposition to bacterial or fungal proliferation in the gynecological and digestive systems.

Scientists hope that, in the coming years, bacteria will develop resistance to antibiotics such as norfloxacin, ciprofloxacin, amoxicillin, ampicillin, and others. At the moment, only fosfomycin-trometamol appears to be sufficiently robust against this effect.