Paediatric idiopathic myelofibrosis.

Pediatric myelofibrosis is a rare disorder. It is usually secondary to other diseases. Rarely, when no underlying cause is found, it is termed idiopathic. We present here, a rare case of idiopathic myelofibrosis in a 10 year old male child. Bone marrow aspirate was dilute. Bone biopsy showed marrow fibrosis, with grade 2-3 reticulin fibres, with no evidence of granuloma, parasite or infilterative disorder. Acid fast bacillus stain was negative. Iliac lymph node biopsy showed reactive sinus histiocytosis with extramedullary hematopoeisis. Thus, diagnosis of pediatric idiopathic primary myelofibrosis was made. Idiopathic pediatric myelofibrosis should be suspected in a child with progressive pallor, hepatosplenomegaly and dry tap on bone marrow aspiration and marrow fibrosis on bone biopsy, after exclusion of secondary causes.