N21
Non-billableCalculus of lower urinary tract
Calculus of lower urinary tract
This is a header/category code. For billing purposes, use a more specific child code from the list below.
Coding Notes
Includes
Conditions included under this code
- calculus of lower urinary tract with cystitis and urethritis
Excludes 2
Conditions not included here, but the patient may have both
- •certain conditions originating in the perinatal periodP04-P96
- •certain infectious and parasitic diseasesA00-B99
- •complications of pregnancy, childbirth and the puerperiumO9A)O00
- •congenital malformations, deformations and chromosomal abnormalitiesQ00-Q99
- •endocrine, nutritional and metabolic diseasesE00-E88
- •injury, poisoning and certain other consequences of external causesS00-T88
- •neoplasmsC00-D49
- •symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classifiedR00-R94
Child Codes (4)
ICD-11 Equivalents(1)
ICD-11 Equivalents
View full mappingCorresponding ICD-11 codes from the WHO crosswalk mapping
Also Known As / Clinical Terms(5)
Frequently Asked Questions
What is the ICD-10 code for calculus of lower urinary tract?
The ICD-10-CM code for calculus of lower urinary tract is N21. The full clinical description is "Calculus of lower urinary tract". N21 is a non-billable header code. Use a more specific child code for billing purposes.
What does ICD-10 code N21 mean?
ICD-10-CM code N21 represents “Calculus of lower urinary tract”. It is classified under Chapter 14: Diseases of the Genitourinary System and is a non-billable header code. Use a more specific child code for billing purposes.
Is N21 a billable code?
No, N21 is a non-billable header code. You need to use one of its more specific child codes for billing. There are 4 child codes under N21.
What chapter is N21 in?
N21 is in Chapter 14: Diseases of the Genitourinary System (codes N00-N99).
What are the subcategories under N21?
N21 has 4 child codes, including: N21.0 (Calculus in bladder), N21.1 (Calculus in urethra), N21.8 (Other lower urinary tract calculus), N21.9 (Calculus of lower urinary tract, unspecified).
What are the UMLS CUIs for N21?
N21 is linked to 2 UMLS Concept Unique Identifiers: C0156264, C4290236. The UMLS (Unified Medical Language System) integrates multiple biomedical vocabularies maintained by the U.S. National Library of Medicine.
How does N21 relate to ICF functioning codes?
ICF (International Classification of Functioning, Disability and Health) codes describe how conditions like calculus of lower urinary tract affect a person's functioning — body functions, activities, participation, and environmental factors. AutoICD provides ICF Core Sets for 12+ conditions and can map clinical text to ICF categories automatically. Browse the ICF directory to explore functioning codes.
What is the ICD-11 equivalent of N21?
N21 maps to the ICD-11 code: GB71.Z (Calculus of lower urinary tract, unspecified).
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Includes SNOMED Clinical Terms® (SNOMED CT®) used by permission of SNOMED International. Includes content from the UMLS Metathesaurus, courtesy of the U.S. National Library of Medicine.