Cataract in diseases classified elsewhere (H28)
The ICD-10 code H28 is used to identify cataracts that arise as a result of other underlying medical conditions rather than from aging or injury. This code is specifically for cataracts related to systemic diseases or metabolic disorders.
This category covers cataracts caused by a variety of conditions, including degenerative disorders, nutritional deficiencies, and dehydration. It also includes cataracts associated with systemic illnesses such as idiopathic hypoparathyroidism, pseudohypoparathyroidism, and syndromes involving multiple symptoms like polyneuropathy, hearing loss, and retinitis pigmentosa. Terms like "Tetanic cataract" and "Hyperferritinemia cataract syndrome" are examples of specific conditions linked to this code. Understanding that these synonyms all point back to H28 helps medical coders select the correct ICD-10 code for cases where cataract is present alongside an underlying systemic disorder, ensuring precise medical documentation and billing.
Diseases of the eye and adnexa (H00–H59)
Disorders of lens (H25-H28)
- H28 Cataract in diseases classified elsewhere
Cataract in diseases classified elsewhere (H28)
Instructional Notations
Code First
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
- underlying disease, such as:
- hypoparathyroidism E20
- myotonia G71.1
- myxedema E03
- protein-calorie malnutrition E40 E46
Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.
