The renal biopsy of a 6 years old boy with recurrent gross hematuria shows IgA nephropathy. The urinary protein excretion is 130 mg/day. Which of the following is the most appropriate next step in the management:

a. Administer corticosteroids(Ref: Nelson's 20/e p 2497, Ghai 8/e p 476)Treatment of IgA nephropathy: The primary t/t is proper BP control; Other drugs found useful are:Fish oil (omega-3 fatty acids): An anti-inflammatory agent and it prevents the rate of renal progressionImmunosuppressive therapy: Done with corticosteroids with or without cytotoxic therapyACE inhibitors and Angiotensin II receptor antagonists: role in reducing proteinuriaProphylactic antibiotics and tonsillectomy: may reduce frequency of gross hematuria but no effect on progression of renal ds.