Question

As a physician, you have a patient with symptoms that suggest a hepatitis A infection, but you have not been able to detect viral proteins in the blood. Knowing that hepatitis A is an RNA virus, what lab tests could you perform to support your diagnosis? Explain the results that would support your hypothesis.

Short answer

The diagnosis of the hepatitis A infection can be confirmed with a laboratory analytical procedure, such as RT-PCR.

The PCR results of the patient are compared with the hepatitis viral RNA to confirm the disease.

Step-by-step solution

Hepatitis A

Hepatitis A is a viral infection that affects the liver, spreading through close contact with the other infected person. The hepatitis A virus causes this infection, which is curable by a vaccine.

Lab tests for diagnostic purposes

Since hepatitis is an RNA virus infection, the best-suited method to detect the hepatitis virus is RT-PCR.

PCR is the polymerase chain reaction that can be used to detect the RNA present in the viruses. It can amplify the genetic material present in the hepatitis A virus.

Confirmation of the hepatitis A infection

The infection present in the patient’s blood has to be confirmed to identify whether it is hepatitis A or not. For this, the mRNA present in the patient’s blood is isolated and converted into complementary DNA (cDNA) by the method of reverse transcription.

The amplification of the cDNA is done with the help of RT-PCR. The RNA sequence present in the patient is compared with the hepatitis A virus RNA to confirm the infection to be the hepatitis infection.