UTIs (urinary tract infections) are infections that affect the bladder (cystitis) or the kidneys (pyelonephritis) in the urinary tract. UTIs are more common in women than men.
Signs and symptoms that may indicate you have a bladder infection include:
- Urinating frequently
- Urgent need to urinate
- Pain or burning when urinating
- Blood in the urine (hematuria)
- Cloudy or dark urine
- Urine with an unusual odor
- Lower abdominal discomfort
Symptoms of a kidney infection may include the symptoms of a bladder infection and:
- Fever
- Pain in the flank (one or both sides of the lower back, where the kidneys are located)
- Nausea
- Vomiting
See a doctor right away if you have symptoms of a kidney infection because delaying treatment can lead to serious complications.
What Causes a UTI?
UTIs (urinary tract infections) are caused by bacteria entering the urethra and traveling up into the urinary tract.
Risk factors for developing UTIs include:
- Frequent sexual intercourse
- Bladder or kidney infection that occurred in the past 12 months
- Diabetes
- Conditions such as kidney stones or ureteral reflux that block or change the flow of urine in the kidneys
- Use of spermicides for birth control
- A genetic predisposition to UTIs
- For men, not being circumcised or having insertive anal sex
How Is a UTI Diagnosed?
UTIs (urinary tract infections) are usually diagnosed with a urine test.
- Urinalysis
- Urine culture
Additional testing may be needed to check for abnormalities in the kidneys, ureter, bladder, or urethra, or for kidney stones in people who have recurrent bladder infections. Tests for recurrent bladder infections may include:
- Computed tomography (CT) scan
- Ultrasound
- Cystoscopy
What Is the Treatment for a UTI?
UTIs (urinary tract infections) are usually treated with antibiotics.
Antibiotics used to treat bladder infections include:
- Nitrofurantoin (Macrobid)
- Trimethoprim-sulfamethoxazole (Bactrim)
- Fosfomycin (Monurol)
Phenazopyridine (Pyridium which is available by prescription, or Uristat, which is available over-the-counter [OTC]) are used to numb the bladder and urethra and reduce the burning pain of some UTIs.
Cranberry juice is often touted as a home remedy for UTIs, but there are no good studies on the effectiveness of cranberry juice for treating a bladder infection. It probably is not harmful but it is unlikely to be helpful.
Medications to treat kidney infections include:
- Antibiotics: the choice depends on the bacteria causing the infection and the severity of the infection
- Levofloxacin (Levaquin)
- Ciprofloxacin (Cipro)
- Trimethoprim-sulfamethoxazole (Bactrim)
- Amoxicillin (Amoxil, Trimox)
- Medications for fever and pain
- Intravenous (IV) antibiotics and fluids may be given in a hospital in patients who have high fever, severe pain, or cannot keep down food or fluids
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https://www.uptodate.com/contents/urinary-tract-infections-in-adults-the-basics?search=UTI&source=search_result&selectedTitle=2~150&usage_type=default&display_rank=2
https://www.webmd.com/a-to-z-guides/news/20130604/can-you-skip-antibiotics-for-urinary-tract-infection#1