Table 2.
Proposed work-up for a child being evaluated for a classical MPN
| Family history |
| Personal medical history |
| Review of systems |
| Physical exam |
| Labs: |
| • CBC with differential |
| • Hepatic function panel |
| • Erythropoietin level |
| • LDH |
| • Iron/Ferritin/TIBC |
| • von Willebrand panel and multimers* |
| Bone marrow: |
| • Aspirate for flow cytometry |
| • Biopsy |
| • assess iron stores |
| • assess cellularity |
| • assess morphology |
| • assess for fibrosis |
| Genetic testing: |
| JAK2 |
| MPL** |
| CALR** |
| Can consider broader myeloid gene panel if triple negative |
| If a patient does not seem to clearly fit an MPN diagnosis, care must be taken to rule out other disorders that could lead to secondary polycythemia, thrombocytosis, or myelofibrosis (such as infectious, inflammatory, or congenital disorders) |
CBC=complete blood count, LDH=lactate dehydrogenase, TIBC=total iron binding capacity
*
acquired von Willebrand’s disease generally occurs with extreme thrombocytosis, we generally perform this test in patients with platelet counts >1000×109/L or with bleeding symptoms
**
If JAK2 mutation is identified, testing for CALR and MPL mutations in ET, PMF, or pre-PMF patients is not indicated.