We describe the clinical, hematological and histomorphological features in 
children of primary myelodysplastic syndrome (MDS) seen at the All India 
Institute of Medical Sciences over three years (Jan 2001-Jan 2004). Twenty-one 
patients of primary MDS aged 17 year or less were classified using the latest 
proposed WHO classification for Pediatric MDS. The median age was 9 years with 
male predominance (80%). Pallor was present in all the cases while fever and 
bleeding diathesis was present in more than 50% of the cases. Morphological 
assessment of the peripheral blood showed macrocytosis in 50%, pancytopenia in 
15% and blast cells in 45% of cases. A complete analysis of clinical features in 
conjunction with the bone marrow profile revealed 8 cases of refractory 
cytopenia (RC), 3 cases of refractory anemia with excess blasts (RAEB), 5 cases 
of refractory anemia with excess blasts in transformation (RAEB-T), 4 cases of 
Juvenile myelomonocytic leukemia (JMML) and a solitary cases of acute myeloid 
leukemia (AML) in Downs syndrome. These children were followed up from 1-36 
months (mean 15 months). Three patients of RAEB-T progressed to AML within 3-4 
months. RC had the best prognosis and all are alive and under regular follow up. 
The solitary case of AML of Downs syndrome died 1.5 months after initial 
diagnosis. All 3 cases of RAEB are under regular follow-up and doing well. Three 
cases of RAEB-T died (all had progressed to AML); the remaining 2 cases were 
lost to follow up. Of the 4 cases of JMML 1 died within 6 months of diagnosis; 
the other 3 cases are under regular follow up of whom 1 has a progressively 
increasing blast count. We conclude that the latest proposed WHO classification 
for Pediatric MDS can be successfully applied to all cases of primary MDS.