Down syndrome, transient myeloproliferative disorder, and infantile liver fibrosis.

Background: In neonates, Down syndrome is rarely accompanied by the leukemoid reaction called transient myeloproliferative disorder.

Procedures And Results: We present clinical and histopathologic data of another Down syndrome neonate with transient myeloproliferative disorder and severe infantile liver fibrosis. These findings in our patients are compared in detail with the 20 cases published previously. Similar clinical and laboratory findings were present in all 21.

Conclusions: Knowing the cellular mechanism of hepatic fibrosis and its modulation by growth factors (e.g, platelet-derived growth factor), a pathogenetic link between transient myeloproliferative disorder and the development of liver fibrosis in Down syndrome neonates seems probable. An association of this triad of findings no longer appears to be accidental.