Obstructive and reflux uropathy (N13)
ICD-10 code section N13 covers obstructive and reflux uropathy, conditions characterized by blockage or backward flow of urine affecting the kidneys and ureters. These codes are used to specify various forms of urinary tract obstruction and reflux that can impair kidney function.
This section includes detailed codes for different types of hydronephrosis caused by specific obstructions, such as ureteropelvic junction blockage (N13.0), ureteral strictures (N13.1), and kidney or ureter stones causing obstruction (N13.2). It also addresses hydroureter, which is a dilation of the ureter due to obstruction (N13.4), and pyonephrosis, an infected hydronephrosis (N13.6). Vesicoureteral reflux (backflow of urine from bladder to kidney) with or without reflux nephropathy is classified under N13.7 and its subcodes, clarifying the presence and side of kidney damage. For example, primary or secondary vesicoureteral reflux is captured by codes like N13.70 and N13.71. Other obstructive uropathies related to prostate enlargement, malignancy, or mechanical causes fall under N13.8. When the obstruction or reflux is unspecified, N13.9 is used. These codes help healthcare providers document and identify specific urinary tract obstructions or reflux conditions precisely, assisting in diagnosis, treatment planning, and reporting.
Diseases of the genitourinary system (N00–N99)
Renal tubulo-interstitial diseases (N10-N16)
N13 Obstructive and reflux uropathy
- N13.0 Hydronephrosis with ureteropelvic junction obstruction
- N13.1 Hydronephrosis with ureteral stricture, not elsewhere classified
- N13.2 Hydronephrosis with renal and ureteral calculous obstruction
N13.3 Other and unspecified hydronephrosis
- N13.30 Unspecified hydronephrosis
- N13.39 Other hydronephrosis
- N13.4 Hydroureter
- N13.5 Crossing vessel and stricture of ureter without hydronephrosis
- N13.6 Pyonephrosis
N13.7 Vesicoureteral-reflux
- N13.70 Vesicoureteral-reflux, unspecified
- N13.71 Vesicoureteral-reflux without reflux nephropathy
N13.72 Vesicoureteral-reflux with reflux nephropathy without hydroureter
- N13.721 Vesicoureteral-reflux with reflux nephropathy without hydroureter, unilateral
- N13.722 Vesicoureteral-reflux with reflux nephropathy without hydroureter, bilateral
- N13.729 Vesicoureteral-reflux with reflux nephropathy without hydroureter, unspecified
N13.73 Vesicoureteral-reflux with reflux nephropathy with hydroureter
- N13.731 Vesicoureteral-reflux with reflux nephropathy with hydroureter, unilateral
- N13.732 Vesicoureteral-reflux with reflux nephropathy with hydroureter, bilateral
- N13.739 Vesicoureteral-reflux with reflux nephropathy with hydroureter, unspecified
- N13.8 Other obstructive and reflux uropathy
- N13.9 Obstructive and reflux uropathy, unspecified
Obstructive and reflux uropathy (N13)
Instructional Notations
Type 2 Excludes
A type 2 excludes note represents "Not included here". An excludes2 note indicates that the condition excluded is not part of the condition represented by the code, but a patient may have both conditions at the same time. When an Excludes2 note appears under a code, it is acceptable to use both the code and the excluded code together, when appropriate.
- calculus of kidney and ureter without hydronephrosis N20
- congenital obstructive defects of renal pelvis and ureter Q62.0 Q62.3
- hydronephrosis with ureteropelvic junction obstruction Q62.11
- obstructive pyelonephritis N11.1
Clinical Terms
The following clinical terms provide additional context, helping users better understand the clinical background and common associations for each diagnosis listed in this section. Including related terms alongside ICD-10-CM codes supports coders, billers, and healthcare professionals in improving accuracy, enhancing documentation, and facilitating research or patient education.
Azotemia
A biochemical abnormality referring to an elevation of BLOOD UREA NITROGEN and CREATININE. Azotemia can be produced by KIDNEY DISEASES or other extrarenal disorders. When azotemia becomes associated with a constellation of clinical signs, it is termed UREMIA.
Hydronephrosis
Abnormal enlargement or swelling of a KIDNEY due to dilation of the KIDNEY CALICES and the KIDNEY PELVIS. It is often associated with obstruction of the URETER or chronic kidney diseases that prevents normal drainage of urine into the URINARY BLADDER.
Pyonephrosis
Distention of KIDNEY with the presence of PUS and suppurative destruction of the renal parenchyma. It is often associated with renal obstruction and can lead to total or nearly total loss of renal function.
Retroperitoneal Fibrosis
A slowly progressive condition of unknown etiology, characterized by deposition of fibrous tissue in the retroperitoneal space compressing the ureters, great vessels, bile duct, and other structures. When associated with abdominal aortic aneurysm, it may be called chronic periaortitis or inflammatory perianeurysmal fibrosis.
