Symptoms of aseptic urethritis: That is, the patient has frequent, urgent, painful urination and discomfort in the urethra during urination, but routine bacteriological examinations and urine tests are normal and there are no positive findings. It is mostly seen in women and mostly in postmenopausal women and is also known as urethral syndrome. Possible causes include: the withdrawal of estrogen in women after menopause, resulting in atrophy of the urethral mucosa, epithelial atrophy, decreased resistance, and normal flora stimulating the urinary tract, which can produce uncomfortable symptoms such as urinary frequency, urinary urgency, and urinary pain. Routine urinalysis and bacteriological examination cannot detect the causative organism. It may also be related to non-specific infections, such as mycoplasma, chlamydia and tuberculosis causing urinary tract irritation, but routine pathogenic tests are normal. And none of the bacteriological tests can find the bacteria and special cultures are needed to identify them.