Hello,
Thanks for posting your query.
In order to be able to provide you with the most probable diagnosis I would like to know the detailed clinical history if feasible .( like source of infection, onset , duration , progress , present HBV DNA values ( copies / microliter ), anti hbs , hep B e antigen and other markers etc, treatment taken .
Assuming that you had a past hepatitis B infection which was treated adequately and you recovered symptomatically and have a normal liver function the probable causes for your tests reports could be as follows,
1. A hepatits B DNA in the blood in detectable levels( by hep B DNA > 300 copies / ml) indicates presence of actively multiplying hepatits B virus in your blood either due to chronic hepatits B infection or as a carrier of the hepatits B virus .
2. A negative hbsag indicates either resolving infection or successful treatment or abnormal levels of hBV DNA are suggestive of the possibility of an underlying chronic hepatitis and future risk of liver cirrhosis or carcinoma .
Its advisable that patients undergo antiviral treatment for hepatits b till the HBV DNA goes down below 300 copies /ml ie termed as undetectable levels in blood to reduce such risk even if your liver tests are normal .i would like to know about your other markers like anti hbs , hbeag etc to know if you have developed immunity to the infection.

So as of now it's advisable to get a thorough re evaluation by your doctor regarding the present clinical findings and blood tests in comparison with the previous one.
It's very likely that you have been treated for the infection but do have some residual viruses in your blood which are suggestive of chronic infection or carrier state and future risk of liver disorder ( cirrhosis , cancer etc).
Hope I have answered your query .
I'll be available for any follow up queries.
Regards

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Hello,
Thanks for the follow up.
Considering the report you have mentioned its most likely that your infection has not cleared and there is a chronic hepatitis b infection causing such a viral load in your blood .
The quantitative range of most of the assays vary but is approximately around 1.3-8.2 log IU/mL (20-170,000,000 IU/mL). 
1 IU/mL of HBV DNA is approximately 5.82 copies/mL.
So you do have a positive hbv DNA test even though your hbsag is non reactive which suggests that the virus is still present in your blood and though your liver function is normal now I would recommend you to follow up with your doctor for regular check ups to avoid any future risk of liver damage .
As of now you have no acute problem and the situation isn't worrisome or requiring immediate treatment but depending on your whole clinical profile your doctor may pr maynot want to consider preventive antiviral treatments .This decision could be best taken by your treating gadtroenterogist or physician.
Hope I have answered your query.
Kindly accept my answer in case you have no further queries.
Regards

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