ICD-10 Code D55.9 – Anemia due to enzyme disorder, unspecified (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D55.9 – Anemia due to enzyme disorder, unspecified
What it is
D55.9 identifies anemia caused by an enzyme disorder when the specific enzyme defect is not documented. It signals a hemolytic or inherited anemia mechanism, but the chart does not name a more precise subtype.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings may include anemia, fatigue, pallor, jaundice, or evidence of red blood cell destruction, but you should code only what is supported in the record.
When to use this code
Use D55.9 when the provider documents anemia due to an enzyme disorder and does not specify the exact enzyme defect. It also fits when the diagnosis is confirmed but the subtype remains unspecified after evaluation. Do not infer a more detailed code from test names alone.
Do not use for
Do not use this code for anemia with a clearly documented enzyme defect that has a more specific ICD-10-CM code. Also avoid it when the anemia cause is different, such as blood loss, nutritional deficiency, or another hemolytic disorder.
Coding tip
Code the highest documented specificity first; if the enzyme disorder is named, check for a more precise D55 category before using D55.9.