M02.30 — Reiter's disease, unspecified site

BillableUnspecifiedCC

Is M02.30 billable?

Yes, but M02.30 will trip a Medicare edit. M02.30 is a valid, billable ICD-10-CM code for encounters from October 1, 2026 through September 30, 2027. However, CMS lists M02.30 under Medicare Code Editor edit 20, “Unspecified code” — meaning a code specifying laterality (right, left or bilateral) exists in the same family. On an inpatient claim this triggers the edit, because CMS holds that there are very limited circumstances in which laterality cannot be documented.

More specific alternatives

M02.30 at a glance

Code	M02.30
Description	Reiter's disease, unspecified site
Billable	Yes
Code set	ICD-10-CM FY2027
Valid for encounters	October 1, 2026 – September 30, 2027

What Medicare edits apply to M02.30?

The Medicare Code Editor screens inpatient claims before they are grouped. These edits name M02.30 directly.

Unspecified — a laterality-specific code exists — MCE edit 20

A code specifying laterality (right, left or bilateral) exists in the same family. CMS holds that there are very limited circumstances in which laterality cannot be documented.

Which MS-DRGs does M02.30 group to?

M02.30 sits in MDC 08 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.

545Connective Tissue Disorders with MCCmedical
546Connective Tissue Disorders with CCmedical
547Connective Tissue Disorders without CC/MCCmedical

As a secondary diagnosis, M02.30 is a complication or comorbidity (CC), which can move a stay into a higher-paying DRG.

How is M02.30 listed in the Alphabetic Index?

These are the routes through the Alphabetic Index that lead to M02.30. They show the wording a clinician may have documented, which often differs from the Tabular description.

Reiter's disease, syndrome, or urethritis

Excludes1 — never code together — inherited from M02

The conditions below can never be reported together with M02.30 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.

Behçet's disease (M35.2)
direct infections of joint in infectious and parasitic diseases classified elsewhere (M01.-)
postmeningococcal arthritis (A39.84)
mumps arthritis (B26.85)
rubella arthritis (B06.82)
syphilis arthritis (late) (A52.77)
rheumatic fever (I00)
tabetic arthropathy [Charcôt's] (A52.16)

Code first — inherited from M02

The underlying condition below must be sequenced before M02.30. M02.30 describes a manifestation and cannot be the principal or first-listed diagnosis.

underlying disease, such as:
congenital syphilis [Clutton's joints] (A50.5)
enteritis due to Yersinia enterocolitica (A04.6)
infective endocarditis (I33.0)
viral hepatitis (B15-B19)

Excludes2 — not included here — inherited from Chapter 13

The conditions below are not part of M02.30, but a patient may have both at the same time. When documentation supports it, M02.30 and the excluded code may both be reported.

arthropathic psoriasis (L40.5-)
certain conditions originating in the perinatal period (P04-P96)
certain infectious and parasitic diseases (A00-B99)
compartment syndrome (traumatic) (T79.A-)
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)

How long has M02.30 existed?

M02.30 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.

Which conditions are coded to M02.30?

ICD-10 code for Reiter's diseasedefault code