Thyroid experts!


Boxer Insane
Just wondering what you guys would think of these thyroid results. SORRY this is long!

I first looked at Cajun's, my doberman's, thyroid in July - she was about 1.5 years old, shedding excessive amounts, had some areas of thinning hair and a skin infection on her neck. She always has a really distinct dog odor too, by far the smelliest of my 4 dogs, even with weekly baths she smells again right after. As with boxers, hypothyroidism is super common among the breed so I did a simple panel just to see:

Total T4: 1.0 (range 1.0-4.0)
Free T4ng/dl by ED: 1.6 (range 0.7-3.7)

Free T4pmol/L by ED: 20.6 (range 9.0-47.4)
TSH: 0.13 (range 0.05-0.42)

So, I guess the only concerning thing there was that her T4 was as low as it could be while still being considered "normal." To me that was too low given how young she is, but my vet thought this was a perfectly acceptable panel. The shedding got better after about a month of it being terrible, she went into heat in September... maybe something was going on related to hormones??

Fast forward to now, her skin/coat/odor is still not great but the shedding has been pretty normal. She had a raging ear infection that cropped up overnight about a month ago. And now within the past couple weeks she's had a drastic temperament change and is getting snappy with other dogs/people. It's completely uncharacteristic of her and she's being this way with my other dogs, and with people that she's interacted with for as long as we've had her (9 months). I would normally consider her 100% bombproof, and again, this sort of behavior came on with no warning, like a switch was flicked.

SO, checked her thyroid again! The reference ranges are the same as above, so I'll just share her results:
Total T4: 0.7
Free T4ng/dl: 1.5
Free T4pmol/L: 19.3
TSH: 0.09
TGAA: 3% (didn't test last time but anything 0-35% is considered negative/normal)

Her T4 was the first thing to come back and since it's lower than before - and this time even considered technically low - I was SO SURE I was on the right path. But everything else is virtually the same and not really looking like it can be considered hypothyroidism.

My vet is going to once again think I'm a whackjob and I don't know how much more to pursue this issue, should I be worried about the low T4? I know most people don't really have much experience with intact dogs, but assuming she has normal twice a year cycles, she'd be due to go into heat around March-ish... could she be at some stage in her cycle that would account for weird behavior?