'GreyGirl' - Keep up the excellent care that you, your family and your vet are giving Lucky. It is just nearly only a month since you wrote that Lucky had been first diagnosed with IMHA – and look at all the improvements that have happened since that first day.
Have a look at these links – and maybe email them to see what they suggest regarding feeding or suggestions on supplements for Lucky - to give her a boost to her system:
Feeding Raw Bones
Augustine Approved - The Brand
Make sure your vet knows exactly what you are doing – and supervises if you are going to make any changes to her diet.
Also have a look at this link – it is a UK based website – there are heaps of people that have had dogs with IMHA.
Canine Immune Mediated Disease Awareness
As you said in your post – there have been heaps of positives – so focus on those. This is a set back – that is all – and hopefully with the ultrasound and second opinion – you will find the answers that you all need and the news will be better for you all.
Again - Heaps and Heaps of Wishes and