Kidney diseases, lesions and cysts are all possible. This can also include kidney stones. However, an abdominal CT scan (which you mentioned you had) would evaluate for most of these conditions.
You can also consider GI causes - like the appendix (can be ruled out with a CT scan), irritable bowel syndrome, or inflammatory bowel disease. An endoscopy with evaluation of the small bowel can be considered to evaluate for these possibilities.
GYN causes can also be evaluated with a transvaginal ultrasound.
These options can be discussed with your personal physician.
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.
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