Prolonged fever with HSM and anemia in two year old child

A poor child of 1 year presented with fever, was being given ATT for 9 months by previous pediatrician. Condition deteriorated so was brought to me by his  relative few days back. 10 kg, 79 cm height, T 102 to 103 "F for 10 days and h/o fever on - off for last 1 yr. Liver 4 cm and spleen 3-4 cm firm. Edema and ascites +ve. Previous invest :Hb 8, Platelet 160,wWBC 8400, N 55, L 35, M 3, E 6., ESR 25, Bilirubin 0.9,albumin 3.5 CXRs :some nospecific infiltrations in few xrays.

PS : Normocytic Normochromic RBCs. No abnormal cells seen. Ur c/s was once E.coli +ve. Blood sample along with above presentation and in hand invest revealed/clinched  the diagnosis. Suggest diagnosis? What investigations   further proved the 1st suspected diagnosis.