If the urine nitrite is a plus sign in the routine urine test, it indicates the possible presence of urinary tract infection, most commonly Escherichia coli infection, which can reduce nitrite in the presence of Escherichia coli infection, resulting in a positive result for nitrite in the urine. The presence of elevated leukocyte count, elevated leukocyte esterase, etc. It needs to be further identified in combination with its own symptoms, whether it is combined with frequent urination, urgent urination, painful urination, whether it is combined with small abdominal pain, back pain, fever, etc. Therefore, a positive urine nitrite usually indicates the presence of Escherichia coli infection, and further urine culture and drug sensitivity tests are recommended to determine the diagnosis and guide drug treatment.