H20.00
Unspecified acute and subacute iridocyclitis
H20.00 (also written H2000) is a billable ICD-10-CM diagnosis code for unspecified acute and subacute iridocyclitis. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 38 codes in category H20 (Iridocyclitis). Its coding notes include 11 Excludes1 entries and 11 Excludes2 entries.
Excludes1
Not coded here. The listed conditions generally should not be reported together.
- iridocyclitis, iritis, uveitis (due to) (in) diabetes mellitus (E08-E13 with .39)
- iridocyclitis, iritis, uveitis (due to) (in) diphtheria (A36.89)
- iridocyclitis, iritis, uveitis (due to) (in) gonococcal (A54.32)
- iridocyclitis, iritis, uveitis (due to) (in) herpes (simplex) (B00.51)
- iridocyclitis, iritis, uveitis (due to) (in) herpes zoster (B02.32)
- iridocyclitis, iritis, uveitis (due to) (in) late congenital syphilis (A50.39)
- iridocyclitis, iritis, uveitis (due to) (in) late syphilis (A52.71)
- iridocyclitis, iritis, uveitis (due to) (in) sarcoidosis (D86.83)
- iridocyclitis, iritis, uveitis (due to) (in) syphilis (A51.43)
- iridocyclitis, iritis, uveitis (due to) (in) toxoplasmosis (B58.09)
- iridocyclitis, iritis, uveitis (due to) (in) tuberculosis (A18.54)
Excludes2
Not included here. Both codes may be reported if the patient has both conditions.
Also from chapter/block level (11 notes)
- 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)
- diabetes mellitus related eye conditions (E09.3-, E10.3-, E11.3-, E13.3-)
- endocrine, nutritional and metabolic diseases (E00-E88)
- injury (trauma) of eye and orbit (S05.-)
- 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)
- syphilis related eye disorders (A50.01, A50.3-, A51.43, A52.71)
Care settings
How CMS programs treat this code. These are CMS claim edits and list entries, not coverage or eligibility rules.
Home Health Primary
Accepted as the primary (principal) diagnosis on a home health claim. The Home Health Grouper assigns it to the MMTA - Other clinical group.
Source: CMS Home Health Grouper Software v07.2.26, effective October 1, 2026Hospital CC
Counts as a complication or comorbidity (CC) when reported as a secondary diagnosis on an inpatient claim. It does not count when the principal diagnosis is one of the 39 codes in its exclusion list. Some MS-DRGs also ignore a CC or MCC that defines the DRG.
Source: CMS MS-DRG Definitions Manual v44, effective October 1, 2026, Appendix CNotes
Also from chapter/block level (1 note)
- Use an external cause code following the code for the eye condition, if applicable, to identify the cause of the eye condition