Can MRI Replace CT for Urologic Issues?

I’ve had recurrent urinary infections and intermittent left lower back pain for the past three years. I was consulting a government medical college urologist and now seeing a private urologist, who has advised an abdomen and pelvis CT scan with contrast. Due to breathing issues, I’ve already undergone 5 CT scans and am concerned about further radiation exposure. I understand CT KUB (non-contrast) is best for kidney stones. But can I opt for CT KUB (for stones) + MRI abdomen and pelvis with contrast (for soft tissue evaluation)? Would this approach provide what the doctor needs in more detail, with lower radiation? Or should I proceed with the recommended CT abdomen-pelvis with contrast, as it may offer the most detailed imaging? Looking for professional guidance on whether this alternative is suitable.