Yes, having a single functioning kidney can potentially impact your kidney health. With IgAN and a duplex kidney, your working kidney needs to handle more filtration load. While many people live normally with one kidney, it's important to:

Monitor blood pressure closely
Stay well-hydrated
Have regular kidney function tests
Follow a kidney-friendly diet
Tell all healthcare providers about your kidney anatomy
I recommend discussing monitoring strategies with your nephrologist, as they can create a personalized care plan considering your unique anatomy.