We report an 18-month-old boy with trisomy 21 who presented with abundant, symmetrical periosteal hyperostosis and generalised
osteolytic bone disease. Although adequate cytological and immunological studies have not been performed, the clinical course,
routine blood and marrow studies allowed us to recognise megakaryoblastic leukaemia (ML) as the cause of these unique X-ray
appearances.
Conclusion We present a unique case of generalised bone disease in an infant with trisomy 21. The appearances – clinical course and
radiographic appearances – are consistent with ML. Such severe bony changes have not yet been reported in this association.
This observation widens the spectrum of ML
Key words Megakaryocytic leukaemia - Periostitis - Trisomy 21
Received: 7 March 1997 / Accepted: 5 May 1997