Beardie Death~Possible cause?

Question
Our sweet little beardie died early this morning and we can not figure out why it happened. We got 'Lucy' as a package deal with her tank and all supplies this last September through a friend who had rescued her from some guy. Lucy was supposedly 18 months old when we got her and a little over 12 inches long. She looked and acted very normal (a little skinny, but we fixed that) and had a really good appetite up until the beginning of November. The tank is 50 gallons with a 100W Zoo-Med, or 150W Tetra Day-Cyle bulb for basking during the day and a UV blacklight for nappy time. I kept temps at 100/70 normally 85-90/70 during supposed Brumation. The substrate is sand (which I find out today is one of the worst ones) She had a varied diet of greens, fruit, crickets, meal worms, earth worms, and any flies she could catch when she was runnin free. I dusted her food about once a week with Flukers Repti-Care, vitamin-calcium supplement. She always had fresh water and she liked to be misted every couple of days with warm water. In November she started to slow down her eating habits and she started to sleep all day under her log. I got concerned and asked some questions at my pet store and my friend who I got her from. I also looked for info online and from everything I found I was sure she was Brumating. After a few weeks of her not eating much I got very concerned and was told during brumation they can go for a few months without food. Well I am paranoid and kept offering a little something even though she was not eating much. Late last week she started to look thinner so I decided she was getting sick or needed to be forced out of Brumation to eat and be treated if necessary. We had been handling her the last few days and I bumped up the Temp in her cage a little from about 90 to 110. I have offered fresh food the last few days in a row and got her some more crickets and mealworms. Yesterday her beard started getting dark and today when I went in to wake her up her beard was black and she was very lethargic. I took her to have a warm bath (between 80-85 degrees)and she seemed to enjoy it and woke up some. I noticed in the last 24 hours she had gotten quite thin and her eyes looked sunken. I was not able to feed her anything and about 2 hours after her bath she laid there with her mouth open and proceeded to die? Except for the black beard and the thinness she looks normal on the outside. No visible parasites, no injuries, bright eyes, moist mouth, moist healthy looking vent. She pooped the last time she ate so I am leaning away from impaction, but her poop the last 2 times has been mostly the white chalky gunk with some urine. I figured this is because she hasn't eaten anything for food in the last few days but has been getting her water. Would you happen to know what could have caused her death?

Answer
Hello Kelly,

I am very sorry for your loss of Lucy.  
Hm, well, there are several things that could have caused Lucy's death.  
Impaction is a possibility, just because it is so common.  If she was impacted when she started slowing down, it just sat in there & did not pass.  
She was quite small though, for her age at 12 inches.  She should have been more like 18-20 inches though.  Good that you did take her in & help her out though as she had a good home.
It is almost impossible to determine whether or not she had parasites without a fecal examination.  Coccidia, if left untreated, will cause stunting of growth, anorexia, weight loss, & death over time, just due to interrupted nutrient absorption & GI tract balance.
It is unfortunate, but the UV blacklight brand is not a good source at all, for UVB output.  I am afraid that she may have passed away from metabolic bone disease as well.  Her calcium levels were most likely very low.  The calcium dustings should have been 3 times a week, of just straight calcium.  The problem lies with the UVB exposure.  If they do not have adequate UVB exposure, then they cannot absorb calcium & they will not synthesize vitamin D3 either which will leave them weak & begin to leach their bones.
The lack of proper UVB, calcium absorption & her losing weight, would make her prone to stress levels that would increase her coccidia levels.  
Also, the earthworms, & mealworms are very fatty & should not be fed on a regular basis.  Unfortunately, feeding too much fatty foods when young, can contribute to fatty liver disease.  
My main thing is to never let a dragon go into brumation if they are too thin.  Always get a fecal done prior to letting them brumate, if they are going to brumate.  There are so many things that can go wrong if they go in with a pre-existing condition.  Did you consider a necropsy?
We can discuss things further if you would like to.  If you would like to send me a picture of her, you can send it to my home email at:
Drache613@tampabay.rr.com

Tracie