In 2017 my six year old Basenji boy's liver numbers jumped to almost 900! Absolutely no explanation. A scan was done and the doctor said the liver looked "grainy" but still no explanation.
He was checked two months later - and every year since (he's 9.5 now) - and numbers have been completely normal. So strange! One thought was perhaps he had walked through grass that had been fertilized/treated somehow and it affected the liver until being processed out.