N06.21 — Primary membranous nephropathy with isolated proteinuria
Is N06.21 billable?
Yes — N06.21 is billable for FY2027. N06.21 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. N06.21 may be submitted for encounters from October 1, 2026 through September 30, 2027.
N06.21 at a glance
| Code | N06.21 |
|---|---|
| Description | Primary membranous nephropathy with isolated proteinuria |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does N06.21 group to?
N06.21 sits in MDC 11 and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 698Other Kidney and Urinary Tract Diagnoses with MCCmedical
- 699Other Kidney and Urinary Tract Diagnoses with CCmedical
- 700Other Kidney and Urinary Tract Diagnoses without CC/MCCmedical
As a secondary diagnosis, N06.21 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.
How is N06.21 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to N06.21. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Nephropathy › membranous › primary
Excludes1 — never code together
The conditions below can never be reported together with N06.21 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- primary membranous nephropathy with nephrotic syndrome (N04.21)
Inclusion terms
Alternative wording in documentation that is classified to N06.21.
- Idiopathic membranous nephropathy (with isolated proteinuria)
- Primary membranous nephropathy, NOS
Excludes1 — never code together — inherited from N00-N08
The conditions below can never be reported together with N06.21 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- hypertensive chronic kidney disease (I12.-)
Excludes1 — never code together — inherited from N06
The conditions below can never be reported together with N06.21 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
- Proteinuria not associated with specific morphologic lesions (R80.0)
Excludes2 — not included here — inherited from Chapter 14
The conditions below are not part of N06.21, but a patient may have both at the same time. When documentation supports it, N06.21 and the excluded code may both be reported.
- certain conditions originating in the perinatal period (P04-P96)
- certain infectious and parasitic diseases (A00-B99)
- complications of pregnancy, childbirth and the puerperium (O00-O9A)
- congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury, poisoning and certain other consequences of external causes (S00-T88)
- neoplasms (C00-D49)
- symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)
Code also — inherited from N00-N08
Two codes may be needed to describe the condition fully. Whether N06.21 is sequenced first depends on the reason for the encounter.
- any associated kidney failure (N17-N19).
How long has N06.21 existed?
N06.21 first appears in FY2024.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.