cbc

esr 

crp

Urine r/e(may show dysmorphic red blood cells and casts with an elevated protein:creatinine ratio)

serum iga levels

and other test to rule out other diagnosis

aso titer

c3 c4 levels

if neurological findings

mri brain

endoscopy

kidney biopsy (for mesengial iga deposits or cresents formation?

indication for steroids 

Persistent nephrotic syndrome

Crescents in more than 50% of glomeruli

Severe abdominal pain

Substantial GI hemorrhage

Neurologic system involvement

Intrapulmonary hemorrhage