PB1854 MYELOFIBROSIS DUE TO SEVERE VITAMIN D DEFICIENCY RICKETS

Background: The association between severe active infantile rickets and myelofibrosis has been reported as Von Jaksch's anemia since 1937. Vitamin D deficiency rickets is a common condition in infants and children of developing countries including Egypt. Despite this fact only 26 patients with myelofibrosis due to severe vitamin D deficiency rickets have been reported in the literature worldwide and none from Egypt. Aims: To report cases of myelofibrosis due to severe vitamin D deficiency rickets and to highlight the importance of considering this rare condition in the differential diagnosis of hypochromic microcytic anemia with splenomegaly in infants. Methods: retrospective description of patients diagnosed as myelofibrosis due to severe vitamin D deficiency rickets for a 6 month period at the Alexandria University Children's Hospital. After taking informed consent from their legal guardians, patients have been subjected to history taking, clinical examination, and laboratory investigations including bone marrow biopsy (BMB). Results: Five patients have been included. Four males and one female, with an age ranging from 6 to 22 months at presentation. They presented with clinical signs of active rickets (wide anterior fontanel, frontal bossing, rachitic rosaries, and hypotonia). They all had an enlarged spleen by examination, confirmed by ultrasonography. Their blood picture showed a hypochromic microcytic anemia (Hb 5 to 8.6 g/dL) with normoblasts, anisopoikilocytosis, teardrops and pencil cells, thrombocytopenia (platelet count 25 to 132 x10 3 cell/cmm, normal in one patient) and a normal white cell count showing monocytosis and immature forms (promyelocytes, myelocytes and band cells). Their chemistry was significant for low calcium, low phosphorus and very high alkaline phosphatase (ALP 922 ‐ 4678 U/L). Bone marrow was done and showed thickened trabeculae and increased bone marrow fibrosis using reticulin stain (picture). Unfortunately, the patients presenting with a symptomatic anemia had a packed red cells transfusion. All patients have been started on therapeutic doses of Vitamin D with rapid correction of their blood counts and gradual normalization of their chemistry parameters. Summary/Conclusion: It is important to raise clinicians’ awareness to such a rare but yet easy to diagnose condition to avoid unnecessary transfusions and investigations and delays in treatment. The treatment of myelofibrosis due to severe vitamin D deficiency rickets is very simple and effective.