Lyrica works like gabapentin. If is newer and expensive, so often you have to fail gabapentin (which can be that it does not work well enough or that the side effects are too much to tolerate at a dose that is high enough to work) in order to insurance/MC to pay for it. I am pretty sure that Lyrica helps restless legs also.
Another option is Cymbalta. The way that it works is different than the way that gabapentin/neurontin and Lyrica work. It is also a new drug and good for peripheral neuropathy pain.
Fiber is good for diarrhea (absorps the water and give bulk) and for constipation (absorps water and helps things move along).
WithHope

I have a few small suggestions and comments. First, I want to say that CHOP is a world-class children’s hospital. It is a good place to go if you have a child with a rare illness. This does not mean that it is always the best place possible nor that you do not have to advocate, but there is a lot of potential and experience there including doing pheresis in children.
Second, that it might help just a tiny bit to clarify that wise Dawn means immunoglobulin when she speaks of loading doses. The dose and frequency of immunoglobulin matters. Some doctors are very by-the-book about giving immunoglobulin and give 2 g/kg (loading) dose the first time and then 1 g/kg after that. Each person has a different level that they need for response. If your child needs the equivalent of 1.5 g/kg to respond, she would get a lot better on 2 g/kg and maybe only stay stable or slowly worsen on 1 g/kg per month. The amount of immunoglobulin also may vary with disease activity, circumstance, other infections, etc. If she were given 1 g/kg every two weeks, this actually works like more than 2 g/kg a month. Since you are a critical care nurse, think of this like vancomycin. You want a trough level that is effective. Each person is somewhat different in dose needed to get that trough level and to maintain a trough you can give a larger dose less frequently or a smaller dose more frequently. There are a lot of doctors that do plasmapheresis followed by immunoglobulin as Dawn says–to reduce the antibody load and then fill the system up with non-autoimmune immunoglobulin for protection and to suppress production of bad immunoglobulin. This may be a way to get more impact and to try again with immunoglobulin as the major treatment.
Third, there are a lot of catheter options out there. You may want to discuss your concerns with catheters with a pediatric surgeon or pediatric oncologist or immunologist or infectious disease doctor. I work in a pediatric oncology and immunodeficiency clinic and we see lots of catheters. I would not be discouraged by two infections. There are double lumen ports through which people can do plasmapheresis. They are typically rather large for an 8 year old, but you could ask if this was an option. You could do a temporary pheresis line for the first round of pheresis to see if it works well before committing to a permanent line capable of doing pheresis since these lines are bigger in order to manage the rate of blood flow for plasmapheresis.
Fourth, I have seen imuran used very sucessfully in immune-mediated conditions and with considerably less side-effects than in a bone marrow or solid organ transplant situation (in which the dose is often pushed high to prevent rejection/GVHD). The biggest positive about imuran is that the goal of its use is to reset the immune system–to cure–whereas, in reality immunoglobulin (and predominantly steroids) is addressing the manifestations of the illness not its cause. It is just that people have to be really patient with imuran because it requires slow and steady persistence and may take 18 months or longer to show it is working. Lots of people get impatient and keep increasing imuran and this can lead to infections or other complications of immunosuppression. You have to have patience for imuran to work and often have to have an additional way to limit damage until the underlying disease starts to get better.
WithHope for a cure of these diseases

I also have bilateral foot drop, feet that get really cold and a neuropathy which really does not like either hot or cold body parts so I HAVE to wear socks. At the worst of this, I had to wear two pairs of socks to stay warm and to provide extra cushioning for sore feet. I have three suggestions.

First and probably the best, is that AFOs (Ankle Foot Orthotics) make a huge difference in walking. They keep the toes from catching on the ground and support the ankle. Search through some of the threads about these and see if you can get some. Best are those made for you, but some people have to advocate hard to get them with doctors/insurance because they are more expensive. The advantages are that they are made to fit your lower leg and foot exactly and so you do not get sores. They can be made to extend enough under the toes to keep them straight.

Second, as I got stronger, I found that shoes with a firm sole help. I went to a family run shoe store that advertised in the Yellow Pages to help fit shoes with AFOs or medical foot problems (I just looked in the Yellow Pages and it was under Shoes-Orthopedic although I remember looking under orthotic???). There I tried on several shoes until I found a pair that it was easier for me to walk in. I also went at a less busy time, so I got attentive advice from people used to helping people with walking challenges. I am not a shoe person, but I like comfortable, conservative shoes. The best kind without AFOs, for me, are New Balance W576. I got them in black so I could wear them to work and they look less like “tennis shoes”. I have a very narrow foot so other cross-trainers might work for others. New Balance is about the only company that makes narrow “athletic” shoes. These have enough sole width to help with the imbalance I have, have a firm sole to help me not trip unless I am tired from trying to walk too far, support my ankles, are light so I don’t get more tired walking when picking my legs up more to compensate for the foot drop, and are warm and comfy as well. I’m a little self-conscious when I wear them to church, but I figure it is better to be able to go to church than what I look like. 😀

Third, at home, have you tried slippers like Isotoner. For me, these have a rubber heel with some strength to help a bit with the tripping and sides to help keep the feet warm. But the tops are flexible enough you probably as well could straighten your toes out through them. An added bonus is that the rubber sole helps to prevent sliding/falling! One of the hard wired habits I have is that I have always taken my shoes off as soon as I get home and ran around in socks. The slippers feel enough like “no shoes” to not drive me batty, but help compensate for the other challenges that now are present.

WithHope for a cure of these diseases.