Brief Answer:
Greater than 3 times normal. More tests needed.

Detailed Answer:
Hello Mr XXXXXXX
How are you? Thanks for writing to HCM. My name is Dr Suresh and will attempt to answer your question today.
SGOT (AST) and SGPT (ALT) are enzymes which are normally present inside the liver cells. But when the liver cells get damaged, these enzymes are released into the blood and thus their levels are raised when tested. Their level will usually tell us regarding the degree of damage to the liver. Increases of upto twice the normal levels can be seen in mild infections and are usually not worrisome. But when the levels rise more than three times normal, then we should be concerned for significant liver injury and levels >1000 will reflect an acute emergency.
In your case, you have been diagnosed with Non-A and Non-B hepatitis (commonly called Hepatitis C, although Hepatitis D and E are also Non-A Non-B). The pattern of you liver enzymes fit this diagnosis of chronic liver disease (SGPT > SGOT). I doubt cirhosis has set in yet, or if it has, then it is in the very early stages. (Usually but not always SGOT > SGPT in Cirrhosis).
Your enzyme levels definitely suggests ongoing liver injury (provided previous levels were normal). What would be more helpful for diagnosing you is to see the trend of enzyme levels. If the enzymes continue to show an increase on repeat testing, then it suggests ongoing liver damage and if the enzymes show a decreasing trend, then the liver cells are recovering.
You definitely need other tests right now. It would be helpful if you could provide me your bilirubin levels (increased in cirrhosis), platelet count (lowered in cirrhosis) and Alpha-Feto Protein (AFP) levels (which may suggest development of tumors in the liver).
Along with this you need a Hepatitis C viral RNA load (to see how much virus you have) and also the "Genotype of the virus". This will help us in tailoring the treatment for you as different genotypes respond differently to treatment. Along with this I would also get tested for Hepatitis B, and get a ultrasound scan of the abdomen with a fibroscan specifically to look for cirrhosis of the liver and also to see for any tumors in the liver.
If you have reached the cirrhotic stage of the liver, then additional investigations will become necessary (which I will discuss if your testing is positive).

Please do get back to me with the blood reports and Scan reports. I hope I will be able to assist you in your recovery and guide you further. Please do not hesitate to contact me for any further questions you might have.

Hope you feel better soon.

Dr Suresh Raghavaiah.

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