What is the clinical significance of nitrite in urine?

The presence of nitrites in urine most commonly means there’s a bacterial infection in your urinary tract. This is usually called a urinary tract infection (UTI). A UTI can happen anywhere in your urinary tract, including your bladder, ureters, kidneys, and urethra.

What bacteria cause nitrites in urine?

The presence of nitrite may indicate the presence of E. coli or K. pneumonia; these bacteria produce nitrate reductase, which converts nitrate to nitrite. The leukocyte esterase (LE) test detects the presence of neutrophils as an indication of active infection.

What does a positive nitrite test indicate?

In usual clinical scenarios that involve obtaining a urinalysis (reasonable pretest probability), a positive urinary nitrite indicates a high likelihood of UTI, although it is likely to be present in a minority of patients with UTI.

What antibiotics treat nitrite positive UTI?

We recommend the use of nitrofurantoin or cephalexin in the treatment of cystitis. If LE is negative, nitrofurantoin is preferable to cephalexin. Second or third generation cephalosporins are appropriate antibiotics in the management of complicated UTI or when pyelonephritis is highly suspected.

Does positive nitrites always mean UTI?

A positive result on the nitrite test is highly specific for UTI, typically because of urease-splitting organisms, such as Proteus species and, occasionally, E coli; however, it is very insensitive as a screening tool, as only 25\% of patients with UTI have a positive nitrite test result.

Can you have nitrites in urine without leukocytes?

The presence of nitrites in the urine is highly specific to certain bacterial infections. Nitrites do not occur with all types of bacteria. An absence of leukocyte esterase in the urine means that the urine is not likely to contain white blood cells, so it is not likely to be carrying infectious agents.

Can you have nitrites in urine without infection?

If there are nitrites in your urine, it may mean that you have a UTI. However, even if no nitrites are found, you still may have an infection, because bacteria don’t always change nitrates into nitrites.

What’s the difference between leukocytes and nitrite?

Leukocyte test: a positive test will give a dark tan to purple color. If Leukocytes test is negative and Nitrite test is negative: no sign of UTI (if symptoms continue, test again or consult healthcare provider). If Leukocytes test is negative or trace but Nitrite test is positive: results suggest UTI.