Which component might confirm the diagnosis of a urinary tract infection in a urinalysis?

The presence of nitrates in a urinalysis is a key indicator that can confirm a urinary tract infection (UTI). Nitrates are not normally found in urine, but certain bacteria, which are often responsible for UTIs (such as Escherichia coli), metabolize urea into nitrates. When urine is in contact with these bacteria, nitrates can be produced, leading to a positive result on a urinalysis.

This laboratory test can be particularly useful because it provides a direct way to assess the likelihood of a bacterial infection. Confirmatory testing might be required to identify the specific bacteria; however, the detection of nitrates is a promising initial indicator of a UTI.

In contrast, while high specific gravity can indicate dehydration or concentrated urine, it does not specifically confirm a UTI. The presence of glucose typically suggests conditions such as uncontrolled diabetes rather than an infection, and low pH urine does not confirm a UTI either, as various factors can alter urine pH without the presence of a bacterial infection. Thus, the presence of nitrates stands out as the most definitive indicator of a urinary tract infection in this scenario.