Difficult to say without examination.
Various types of intrinsic renal disease can lead to decreased function in the absence of obstruction.
Imaging the kidneys with an ultrasound or CT scan may be helpful. If non-revealing, a referral to a nephrologist can be considered to look for intrinsic kidney disease. Obtaining a kidney biopsy can be considered.
Without knowing the cause of the decreased function, it is difficult to predict whether the kidney would resume normal function.
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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