H20.019Primary iridocyclitis, unspecified eye

H20.019 is the ICD-10-CM diagnosis code for primary iridocyclitis, unspecified eye. It belongs to category H20 (iridocyclitis), block H15-H22 (disorders of sclera, cornea, iris and ciliary body) and chapter 7 (diseases of the eye and adnexa). It is billable, so it can be reported on its own for dates of service from October 1, 2026 through September 30, 2027.

Within H20.01, choose H20.019 (unspecified eye) only when documentation doesn't support a more specific option: right eye (H20.011), left eye (H20.012) and bilateral (H20.013).

As a secondary diagnosis it is a CC (complication or comorbidity), which can move an inpatient stay into the "with CC" MS-DRG of its family, unless the principal diagnosis excludes it.

In MS-DRG v44.0, it is part of the grouping logic for DRG 124 (Other Disorders of the Eye with MCC or Thrombolytic Agent, relative weight 1.2471) and DRG 125 (Other Disorders of the Eye without MCC, relative weight 0.7702), in MDC 02 (Diseases and Disorders of the Eye), as a principal or secondary diagnosis. The DRG a claim lands in depends on the principal diagnosis, procedures and any CC/MCC secondary diagnoses.

It is an unspecified code for which a more specific option (often laterality) exists, and the Medicare Code Editor flags it for review on inpatient claims.

It has been part of ICD-10-CM since the code set took effect on October 1, 2015 and hasn't changed since.

Before ICD-10, this condition was coded in ICD-9-CM as 364.01 (primary iridocyclitis).