Myelophthisis

This code represents myelophthisis, a condition characterized by the displacement of normal hematopoietic bone marrow by abnormal tissue, such as fibrosis, tumor cells, or granulomas. This infiltration leads to impaired blood cell production and often results in pancytopenia.

Use this code when documentation explicitly states myelophthisis as the diagnosis, often in the context of a bone marrow biopsy revealing marrow replacement. It is typically associated with underlying conditions like metastatic cancer, granulomatous diseases, or severe infections affecting the bone marrow.

• Carefully review documentation to differentiate myelophthisis from other forms of myelofibrosis, as indicated by the Excludes1 notes.
• Always code the underlying cause of the myelophthisis, if known, as the primary diagnosis, with myelophthisis as a secondary diagnosis.
• Ensure the documentation clearly supports the diagnosis of myelophthisis, rather than just general bone marrow suppression or aplasia.