You have had a pretty comprehensive evaluation, including MRI imaging and various urine tests.
A scrotal ultrasound can be considered to look for epididymitis. A prostatic massage can be done to express any prostatic fluid that can be sent for analysis and culture.
If infection has be completely ruled out, a cystoscopy can be done to evaluate the lower GU tract.
These options can be discussed with your urologist or in conjunction with another urological opinion.
Followup with your personal physician is essential.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Kevin, M.D.
kevinmd_b