Extreme weight loss in cat

Question
Hi there, doc.  I'm hoping you might be able to shed some light on an issue I'm having with my 11 year old DMH Maine Coon mix cat, Moot.  I am a licensed veterinary technician and cat rescuer, just so you know my background!

Moot was a healthy 17 plus pounder a year ago.  In the last few months, he has dropped to 13 lbs. and is all skin and bone.  He lost two of those pounds in just 5 weeks.  We've been to our vet twice and are currently waiting for an ultrasound appointment with another veterinarian to be scheduled by my vet.  Moot has had a geriatric blood panel done, CBC, urinalysis and T4.  Everything came back fine, barring a very small amount of proteinuria and a slightly low WBC count (which my vet attributed to his blood machine).  The vet did not palpate any obvious abnormalities in the cat's abdomen, nor did he hear anything wrong with the heart or lungs.  He is not tachycardic.  He has been eating, though probably not as much as he used to, and he does drink (but is not pu/pd). He is urinating, and I have not seen any diarrhea or vomiting.  Basically, I just wanted to pick your brain to see what you might do in this situation.  I was considering having a free T4 and T3 run to make positively sure this isn't an insidious form of hyperthyroidism, and maybe do a urine protein/creatinine ratio.  I'm even considering retesting him for FIV/FeLV.  He was tested as a kitten and was negative, and has always been an indoor cat.  I'm not really sure what to do at this point...I guess I'm just really worried and trying to gather as much info as I can.  I'm thinking cancer, but hoping it's something less awful, like a malabsorption problem.  What are your thoughts?  Anything you'd suggest doing at this point, or any tests you might run?  Anything would be appreciated, I'm just on the hunt for as much information as I can get my hands on and any suggestions that my vet may have not thought of.  I am starting to feed him kitten food to boost his caloric intake and giving him lots of treats and love.  Thanks a lot, and I hope you're having a good weekend.

Jes

Answer
Jes -

It sounds as if you have done a thorough diagnostic workup.  Without seeing your pet and performing exam, I cannot diagnose your cat's condition. However, it does sound as though there is some malabsorption problem or, unfortunately, some sort of cancer.

Cats tend to have gastrointestinal problems that may go unnnoticed becasue they are stoic animals.  Have a GI assay performed at Texas A&M University GI Labs. The GI lab was formed with anmimals in mind; they also have sentitive tests thay can help determine if there is a malabsorption/GI issue with your cat. The lab has been quite instrumental in helping me to diagnose feline cases especially.  You can email them at gilab@cvm.tamu.edu or phone  - 979.862.2861.  

Best Regards,

Charlotte Sherrell, DVM