How To Treat You Rheumatic Arthritis And Vasculitis?

Dear sir, my self dr.sandip , my mother 49 yr suffering from rheumatic arthritis& vasculitis ,now on investigation ANCA +ve,DS DNA +VE,C3 C4 LOW,ON kidney biopsy showing lupus nephritis grade IV-5. Rheumatologist suggest iv cyclophosphamide.

recent report on 28/04/11 ,HB 10,WBC-12,000,Creatnine-0.7,

todays weight is 48kg.

please suggest initial iv cyclophosphamid dose in this patient,and further openion.