Final answer:
The presence of white blood cells and nitrites in urine suggests a urinary tract infection, as white blood cells are part of the immune response and nitrites indicate the presence of Gram-negative bacteria. A urine culture is often conducted following a positive rapid screening test to confirm the diagnosis.
Step-by-step explanation:
The presence of white blood cells (WBCs) in urine often suggests a urinary tract infection (UTI). WBCs, or leukocytes, are part of the body's immune response to infections, and they are not typically found in urine. An elevated number of these cells indicates the body is fighting an infection in the urinary system. Additionally, leukocyte esterase is an enzyme found in WBCs that, when detected in urine, provides indirect evidence of a UTI.
Nitrites in urine are also indicative of a UTI. Nitrates (NO3-) are normally present in urine, but the conversion to nitrites (NO2-) is caused by Gram-negative bacteria typically associated with UTIs. Therefore, nitrites in the urine can be used to infer a bacterial infection.
Cloudiness in urine is another sign that may indicate the presence of white blood cells or infection. Urine test strips are commonly used to detect and quantify elements like nitrites and WBCs. Positive results on such rapid screening tests often require a urine culture for definitive diagnosis. It is key to collect a clean sample to minimize contamination and ensure accurate results.