I Had A Liver Function Test In July And Results

I had a liver function test in July and results were all normal, I then had another in November and all were normal except my ALT had gone from 23 to 306. I have just had another blood test this week and my ALT has reduced to 40 but my GGT has increased to 106 and Albumin to 51. All the others are normal. Do you know what could cause this at all? Due for a scan next week. thanks