N01.9 — Rapidly progressive nephritic syndrome with unspecified morphologic changes

BillableUnspecifiedMCC

Is N01.9 billable?

Yes, but N01.9 is an unspecified code. N01.9 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, N01.9 is an unspecified or catch-all code. Payers apply additional scrutiny to unspecified codes and many deny them when the medical record supports a more specific option, so check the documentation before selecting N01.9 — the more specific alternatives are listed below.

More specific alternatives

N01.9 at a glance

Code	N01.9
Description	Rapidly progressive nephritic syndrome with unspecified morphologic changes
Billable	Yes
Code set	ICD-10-CM FY2027
Valid for encounters	October 1, 2026 – September 30, 2027

Which MS-DRGs does N01.9 group to?

N01.9 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, N01.9 is a major complication or comorbidity (MCC), which can move a stay into a higher-paying DRG.

How is N01.9 listed in the Alphabetic Index?

These are the routes through the Alphabetic Index that lead to N01.9. They show the wording a clinician may have documented, which often differs from the Tabular description.

Glomerulonephritis › rapidly progressive
Glomerulonephritis › subacute
Nephritis, nephritic › rapidly progressive (albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
Nephritis, nephritic › subacute (albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
Disease, diseased › glomerular › rapidly progressive
Disease, diseased › renal › rapidly progressive
Disease, diseased › renal › subacute
Glomerulonephritis › poststreptococcal NEC › rapidly progressive
Nephritis, nephritic › poststreptococcal › rapidly progressive (albuminuric) (azotemic) (congenital) (disseminated) (epithelial) (familial) (focal) (granulomatous) (hemorrhagic) (infantile) (nonsuppurative, excretory) (uremic)
Syndrome › nephritic › rapidly progressive

Excludes1 — never code together — inherited from N00-N08

The conditions below can never be reported together with N01.9 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 N01

The conditions below can never be reported together with N01.9 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.

nephritic syndrome NOS (N05.-)

Excludes2 — not included here — inherited from Chapter 14

The conditions below are not part of N01.9, but a patient may have both at the same time. When documentation supports it, N01.9 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 N01.9 is sequenced first depends on the reason for the encounter.

any associated kidney failure (N17-N19).

How long has N01.9 existed?

N01.9 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.

Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.