Juvenile myelomonocytic leukemia, in relapse

This code signifies a rare, aggressive form of childhood leukemia characterized by uncontrolled proliferation of myelomonocytic cells, specifically when the disease has recurred after a period of remission. It involves abnormal white blood cell production and often affects infants and young children.

Apply this code when documentation clearly indicates a diagnosis of juvenile myelomonocytic leukemia that has relapsed. This typically follows initial treatment and a subsequent period where the disease was undetectable or in remission. Supporting documentation would include pathology reports, hematology findings, and physician notes confirming the relapse.

• Ensure documentation explicitly states "relapse" for juvenile myelomonocytic leukemia; do not use for initial diagnosis or remission.
• Distinguish from other types of myelomonocytic leukemia or myelodysplastic syndromes.
• Sequence as a primary diagnosis when the relapse is the focus of the encounter.