After 18 months the health problems with my collie are gradually being resolved.  If I hadn't kept tuning into Champdog Forum for information I don't think I'd be getting anywhere.  So now she is on Thyforon for hypothyroidism and will be starting vaccinations for her allergies in a couple of weeks.  I had to tell my vet what to do not ask.  I'm ashamed of the house dust mites though.
Is there anyone reading this who also has or had house dust mites and what they did to eradicate them?  I've always vaccumed first thing every morning because I'm too tired at night.

You cannot eradicate dust mites, all you can do is try to keep on top of them.  Don't be ashamed of them - every house, every pillow, every carpet, bed sheet, curtain etc has them in.  They are simply there.  It's not a failing on your part and I'm sorry that you've been made to feel this way; dust mites are a natural part of the ecology of every single household.  Your job is to keep the numbers as low as possible.  Hoovering daily, washing sheets often, washing dog beds often in particular - wherever she sleeps the most will need to be the cleanest as that's where she'll get the greatest exposure.  I've known a dog go through the immunotherapy vaccinations for dust mites and it worked well.  It may be that courses of steroids are needed occasionally as she will get flare ups, but equally you may find she does just fine with antihistamines - talk to the vet about it (or do your own research ).

Remember the less obvious places, too: wash your pillows, not just the cases, and hoover the mattress and flip it often too top keep them from building up too much.  I read recently that a great way to keep them down in bedding is to 'not make your bed': leave the bedding open to the air which is supposed to help kill them off.  I don't know how true that is, but something to look into perhaps.

One of my girls is allergic to food storage mites, dust mites, black mould spores and blue grass pollen. You are not alone.

Oddly enough - mine had a massive flare up when we got laminate flooring fitted in the previous house and my vet was stunned. I honestly feel that not having carpet made it worse as the dust spores were floating around more. Since moving and going back to fitted carpet - everything is 1000% better. I hoover once a day at least but I do have a shedding breed - if things were different, I'd probably just stick to once a day. If she has a flare up (only around seasons really) I give a small dose of children's piriton. I don't even need the ear flush with steroids anymore. Switching to RAW has helped too but then, the food storage mites were the biggest issue. Although things were really bad initially - we didn't have to go down the vaccine route.

ETA: when we switched to RAW we were stressing that things weren't improving - after the allergy test it all made sense - we were feeding green tripe and the green in the tripe was grass.....blue grass pollen.....!!! Even if you feed kibble and wet tinned - just be aware that anything with tripe in it will contain some form of grass :)

Nearly every dog that I ever heard of having test comes up as allergic to storage and dust mites .as nikita says u can only reduce them as they are in the general environment. If u kibble keep put the food in the freezer it kills storage mites.one of  mine is on immunotherapy  the success rate is around 70 % and best in dogs under 5 apparently. It seems to reduce symptoms but doesmt cure as such . We have been lucky and its helped but We still have to have top ups in the form of topical treatments if there is any sign of problems in her ears which is her key problem area.I also regularly  bath in malesab which is anti fungal and antibacterial all of which helps.she has omega 3 capsules to help her skin . Ut will be a management plan fpr her life and I expect to see the vet roughly 3 monthly to check ears as it's an area I can check.she has swabs taken each time and yet gain this time she needed a top up as there was some malazzia present in one ear starting inflammation .it's one of allergens and around all the time.  I do the monthly inhections rather than doing a vet visit which I do d best ..mine are allergic to some  grasses but are fine with tripe so it's very individual.for some dogs if u feed raw it can be the food the animal is fed on not the actual protein and grain fed chicken is often a big culprits in food allergoes.