Unspecified hydronephrosis

This code represents the dilation of the renal pelvis and calyces due to an obstruction of urine flow, where the specific cause or type of hydronephrosis has not been identified or documented. It indicates a general finding of kidney swelling due to urine backup without further specificity.

Use this code when imaging studies (e.g., ultrasound, CT scan) reveal hydronephrosis, but the physician documentation does not specify the laterality (e.g., right, left, bilateral) or the underlying cause (e.g., calculus, stricture, congenital anomaly). It is appropriate when the provider explicitly states "unspecified hydronephrosis" or when more specific details are unavailable at the time of coding.

• Avoid using this code if laterality or a more specific cause of hydronephrosis is documented; always query for clarification.
• This code is a "not otherwise specified" (NOS) code; strive for greater specificity whenever possible.
• Consider sequencing this code after any underlying condition that may be causing the hydronephrosis, if known and documented.