Hi,

I think it is due to Occult HBV infection,  which  of late,  is the  mostly observed among the patients.

http://www.google.co.in/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&ved=0CCMQFjAA&url=http%3A%2F%2Fwww.jgid.org%2Farticle.asp%3Fissn%3D0974-777X%3Byear%3D2011%3Bvolume%3D3%3Bissue%3D2%3Bspage%3D205%3Bepage%3D206%3Baulast%3DMishra&ei=PQT7U4WWDInIiwLmsYHIDg&usg=AFQjCNHyUI4WNrVRAetBXP7Mrl8w0V3-3A&bvm=bv.73612305,d.cGE&cad=rja

http://www.sciencedirect.com/science/article/pii/S0168170210002649

It can be due to many reasons: [1] Patient may be  carrier only, [2] Patient at present may be negative but later can have positivity, [3] Patient may have received treatment. It is best to check HBeAg satus and serial HBV DNA levels

Occult HBV infection is seen in immunocompromised patients such( eg: CKD patients on  hemodialysis or those  with HIV infection) and is characterized by having -ve HBsAg ,+ve HBcAb and viremia  (+ve HBV-DNA by PCR).HBV carrier usually tend to have +ve HBsAg  and low  or very low viral load by PCR, and sometimes HBV-DNA might be undetectable in HBV carriers, also patients with chronic HBV that receiving neucleoside analogue such as Entecavir can give a similar picture.

It could be due to:

I fully agree the anwer by Cappelletti. 

In regard of Occult HBV. OBI is classically defined as  the presence of HBV-DNA at very low levels  in the liver and/or the serum sample  of  HBsAg negative and   anti-HBc positive patients.  

The most plausible answer is that the patient is under antiviral treatment that successfully inhibit the production of new virions, hence undetectable serum hbvdna. Because HBsAg is produced from the cccDNA template (or integrated HBV genome) and released as sub-viral particles(SVP), serum HBsAg will be positive.

I believe the question was about a patients not on treatemnt

The patient is on or after antiviral treatment or it has a very good immune management of the infection in the inactive carrier state or the tests are not sensitive enough.

one more question:

why we perform pcr in case of direct Elisa that can be used to detect antigen in the blood. generally we assume that through pcr we can detect antigen not antibody directly so here in case of hbsag then why we do pcr if we can detect antigen directly in the blood.

comments plz

These are the possible differencials:

1. Inactive carrier with positive HBsAg, and low (

Dear Fawad Khan

In fact in deciding for treatment of HBV we are looking for at least one excuse for treatment of patient. According to the WHO and AASLD guideline ( The file attached) it seemed the above patient has the minimum criteria for continuing treatment or at least closely follow up, which is elevated ALT. Beside the positive figure of HBsAg, the HBV DNA was not detectable; it needs further more sensitive molecular and serologic test in the term of viral load, as well HBeAg and HBeAb. So, deciding for treatment can be easier after complete configuration of fibroscan grade, age, ALT, and sero-markers of HBV.

This is inactive carrier state of Hepatitis B. However as the patient is young search for additional causes of elevated SGPT like alcohol intake, hepatitis C, hepatitis D, Wilson disease, autoimmune hepatitis. Also get abdominal ultrasound done to check for portal hypertension.

As per world guidelines, since HBV-DNA was 170,000 iu/ml at baseline this patient has e negative hepatitis [not inactive carrier state] and Viread must be continued irrespective of the DNA as dangerous hepatitis flare may occur on stoppage of therapy.

How to interpret

HbSag positive

HBV DNA PCR not detected

HbeAg is positive by elisa

Does this happen?

probably the patient is also Hepatitis δ (+)

Vemu Lakshmi, it may be a very recent state of infection where viremia is still very low to be detectable. But before any inference, how are the results of anti-HBc and anti-HBs? Did you perform a new exam (HBV DNA PCR) on a new sample of the individual?

Probably This is a case of HDV coinfection. please do HDV RNA if possible

Most likely the patients are on antiviral, thereby the production of hbvdna is suppressed. If the patients are not on antiviral, then the serum HBsAg may be from integrated hbvdna, and not from cccDNA which is zero or very low.