N21.8 - Other lower urinary tract calculus

Version 2023
ICD-10:N21.8
Short Description:Other lower urinary tract calculus
Long Description:Other lower urinary tract calculus
Status: Valid for Submission
Version:ICD-10-CM 2023
Code Classification:
  • Diseases of the genitourinary system (N00–N99)
    • Urolithiasis (N20-N23)
      • Calculus of lower urinary tract (N21)

N21.8 is a billable ICD-10 code used to specify a medical diagnosis of other lower urinary tract calculus. The code is valid during the fiscal year 2023 from October 01, 2022 through September 30, 2023 for the submission of HIPAA-covered transactions.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

Index to Diseases and Injuries References

The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10 code(s). The following references for this diagnosis code are found in the injuries and diseases index:

Convert to ICD-9 Code

Source ICD-10 CodeTarget ICD-9 Code
N21.8594.8 - Lower urin calcul NEC

Patient Education


Bladder Diseases

The bladder is a hollow organ in your lower abdomen that stores urine. Many conditions can affect your bladder. Some common ones are:

Doctors diagnose bladder diseases using different tests. These include urine tests, x-rays, and an examination of the bladder wall with a scope called a cystoscope. Treatment depends on the cause of the problem. It may include medicines and, in severe cases, surgery.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases


[Learn More in MedlinePlus]

Ureteral Disorders

Your kidneys make urine by filtering wastes and extra water from your blood. The urine travels from the kidneys to the bladder in two thin tubes called ureters.

The ureters are about 8 to 10 inches long. Muscles in the ureter walls tighten and relax to force urine down and away from the kidneys. Small amounts of urine flow from the ureters into the bladder about every 10 to 15 seconds.

Sometimes the ureters can become blocked or injured. This can block the flow of urine to the bladder. If urine stands still or backs up the ureter, you may get a urinary tract infections.

Doctors diagnose problems with the ureters using different tests. These include urine tests, x-rays, and examination of the ureter with a scope called a cystoscope. Treatment depends on the cause of the problem. It may include medicines and, in severe cases, surgery.

NIH: National Institute of Diabetes and Digestive and Kidney Diseases


[Learn More in MedlinePlus]

Code History