Opus, thanks for the info on cat scratch fever...I did have it when I was 4 so I'm not sure if I could get it again. I guess i better check on that.
Jade, I think the allergy to his saliva would be totally possible. I don't know if there would be a test for that. I'll check with the vet.
Linda....don't want to scare you but it may possibly be 'cat scratch disease'...and you best be tested..needs to be treated with antibiotics.
http://www.petplace.com/cats/bartonellosis-cat-scratch-disease/page1.aspx
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002581/
oops- I guess histo can be outside. Taz's was in his liver. But it is non communicable.
Have you changed something you use on the carpet or bedding? Something you might be allergic to?
Histoplasmosis is internal and he would be obviously sick- or so I think. My poor Tazzy had it and it was horrible.
Does anybody on here have any suggestions. I know he was tested for the Feline Leukemia Virus but what about other tests, like histoplasmosis or fungal?