Neutrophil esterase is a specific enzyme present in neutrophils, which can be tested during routine urinalysis to assess the presence of infection. Neutrophil esterase is a specific enzyme found in neutrophils. The neutrophil esterase test has become one of the routine tests in the routine urinalysis and is usually normal and negative, with a positive test representing the possible presence of a urinary tract infection. However, false positives may occur when the urine is contaminated, the bilirubin in the urine is elevated, or the urine specimen has been left for too long. It is necessary to combine with the patient’s symptoms to determine whether there is an infection or not, such as the presence of symptoms of infection such as frequent urination, urinary urgency, and urinary pain to consider that the infection exists, and can be rechecked again for the routine examination of the urine or a urine culture test to clarify the diagnosis. If the test found abnormal, please follow the doctor’s advice treatment.