High Platlet count and WBC Count??

Our dog hasn't been feeling well for a couple of week, they have run X-rays and ultrasounds with no findings. His WBC last week was 16000, this week its still WBC but his Platelets count is now at 400,000, which is high. Vet is stumped, he is fighting something just what? They are putting him on another round of antibiotics and if not better by Monday then he will go to an internal medicine doctor.

Has anyone experienced this before with their dogs? He is only 3 years old and a Schichon.