ICD-10 Code D57.21 – Sickle-cell/Hb-C disease with crisis (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code D57.21 – Sickle-cell/Hb-C disease with crisis
What it is
D57.21 identifies sickle-cell/Hb-C disease when the patient is having a crisis. Use this code for documented Hb-C sickling disorder with an acute painful or vaso-occlusive episode.
Clinical signs
Clinical features vary; refer to documentation. Common crisis findings include acute pain, swelling, and other signs of vaso-occlusion in a patient with sickle-cell/Hb-C disease.
When to use this code
Use D57.21 when the provider documents sickle-cell/Hb-C disease and an active crisis, such as an acute painful episode or other sickling complication. Code the condition only when the crisis is clearly stated in the record. If the note does not specify crisis, check documentation.
Do not use for
Do not use this code for sickle-cell/Hb-C disease without crisis, or for other sickle-cell syndromes with a different genotype. If the chart is unclear, check documentation.
Coding tip
Match both the hemoglobinopathy and the crisis wording exactly as documented before assigning D57.21.