Urinary tract infections are the most common cause of nitrites in urine. These occur when bacteria infect the bladder, ureters, or kidneys.
A doctor can easily diagnose a urinary tract infection (UTI) by testing a urine sample. Being diagnosed and treated at an early stage can lead to a quick reduction in symptoms and prevent complications.
Nitrites are byproducts of nitrogen waste. Bacteria responsible for an infection feed on this waste, breaking it down into nitrates, which can appear in the urine.
Nitrituria is the medical term for nitrates in the urine.
The most common cause of nitrituria is a UTI. This infection can occur in any part of the urinary tract.
UTIs usually affect the bladder and urethra, which together make up the lower urinary tract.
Infections in the bladder or urethra often have the following symptoms:
- pelvic pressure
- frequent and urgent need to urinate
- blood in the urine
- painful urination
- lower abdominal pain
- burning during urination
- dark or cloudy urine
- foul-smelling urine
UTIs can spread upwards, through ducts called the ureters, and infect the kidneys.
Symptoms of a kidney infection include:
- a high fever
- shaking chills
- back or flank pain
Kidney infections can be very serious. They may require hospitalization and intravenous administration of antibiotics.
A doctor will order a urine sample to test for nitrites if a person shows any indication of a UTI.
They may also order a test for nitrites in the following situations:
- during pregnancy
- as part of a routine checkup
- to monitor known kidney conditions
- prior to surgery
- as part of a diabetes screening
- during hospitalization, especially when a catheter is required
The doctor will order a noninvasive test called a urinalysis. It involves analyzing the urine and can provide results within minutes.
Before the test, a healthcare provider will give the person a sterile plastic cup and cleansing wipes for their genitals. The person will then collect a urine sample in a private bathroom. After urinating into the cup provided, the person will replace the cap and return the sample.
A technician will place several rods, or dipsticks, in the sample. These will test for the presence of nitrites, white blood cells, and protein in the urine. They may also determine pH or acidity levels.
If the urinalysis reveals signs of infection, such as nitrites and white blood cells, a doctor may prescribe antibiotics right away. Or, they may need to send the urine to a lab, to determine what kind of bacteria is present, before prescribing antibiotics.
Antibiotics are usually the first line of treatment when nitrites appear in urine. A doctor will take into account the individual's medical history, any allergies, and the type of bacteria, if it is known, when prescribing an antibiotic.
A doctor may prescribe an alternate antibiotic for someone who is pregnant, as some can be harmful during pregnancy.
A person with a UTI should drink plenty of water to dilute the urine and help to flush out bacteria.
If infection spreads to the kidneys, a person may be hospitalized and administered intravenous antibiotics and fluids.
UTIs in the lower urinary tract cause very few complications when treated promptly.
However, if an infection reaches the kidneys, the following complications can occur:
A pregnant person who has symptoms of infection should see a doctor as soon as possible. UTIs may cause preterm labor or low birth weight.
The most likely cause of nitrites in urine is a UTIs. Most UTIs, especially those in the bladder and urethra, are easy to treat and will clear up within a week of taking antibiotics.
If left untreated, a UTI in the lower tract can spread to the kidneys and cause more severe complications.
Anyone with symptoms of a UTI or kidney infection should see a doctor as soon as possible.