Hepatitis B Virus DNA Can be Amplified Directly From Dried Blood Spot on Filter Paper

Hepatitis B Virus (HBV) infections represent a major public health problem because of the ability of HBV to cause a chronic carrier state. Even though chronic carriers remain largely asymptomatic, a large number of these individuals subsequently develop cirrhosis and primary hepatocellular carcinomas. Dried Blood Spot (DBS) samples are a simple and inexpensive sampling method, especially useful for blood collection in resource poor settings with limited access to diagnostic facilities. The main advantage of DBS samples over routine blood samples is that only a small quantity of blood, is required. They are easy to obtain, stable and can be transported to a reference laboratory at minimal cost. This study was to evaluate the feasibility of DBS samples for direct amplification of HBV DNA bypassing nucleic acid extraction. Results obtained from DBS samples were compared from those from plasma by routine molecular technique and also with those from whole blood. On the whole results for DBS, whole blood and plasma samples for HBV-DNA semi quantitative PCR monitoring, demonstrated very good agreement. This study also represents the first report in Egypt to evaluate the use of DBS to direct amplification of HBV-DNA and concluded that the use of DBS for direct amplification of HBV DNA without nucleic acid extraction was reliable, specific, sensitive, cheap and appropriate method to monitor the HBV infected patients.