Hepatitis C Virus (HCV)

Sample for Hepatitis C Virus (HCV)

1. The best sample is the serums of the patient.
2. The serum is stable for 7 days at room temperature for anti-HCV.
3. This test can be done on the plasma as well.
4. This test can be performed on a random sample.

Precaution for Hepatitis C Virus (HCV)

• Separate serum or plasma immediately to avoid virus degradation by the white blood cells.

Indications for Hepatitis C Virus (HCV)

1. To diagnose the patient with HCV infection.
2. For screening of the blood donor.
3. Should be done to healthcare workers.
4. Advised the drug users.
5. In a person who has sex with HCV positive partner.
6. The patients with HIV positive.
7. In abnormal liver function tests.
8. Blood transfusion or organ transplantation before July 1992.
9. The patients with hemophilia were treated before 1987.

Definition of Hepatitis C Virus (HCV)

1. This was formally called non-A, non-B viral infection (NANB) because no tests were available. This was suspected by the exclusion of HBV and HAV.
2. Later on, the Hepatitis D virus was discovered, and this virus was separated from NANB.
3. In 1991 virus identified was named Hepatitis C Virus (HCV).
4. The second-generation test for HCV was available in 1993.
5. A third-generation test for HCV was available in 1994.
6. First and second-generation tests diagnose only HCV-IgG.

Biology and structure of  Hepatitis C Virus (HCV)

1. Hepatitis C virus (HCV) is a hepatotropic virus. It belongs to the Flavivirus family.
   1. HCV  is a small enveloped virus measuring 55 to 65 nm.
   2. HCV is a small positive-single-stranded RNA virus of the Flaviviridae family.
   3. This was formally called non-A, non-B viral infection because no test was available. This was suspected by the exclusion of HBV and HAV.
2. HCV exists in 4 genotypes or strains:
   1. Core antigen.
   2. NS3 gene.
   3. NS4 antigen.
   4. NS5 antigen
3. HCV infection is unlike HBV because this gives rise to more than 60% as a chronic disease.
4. 20 % of the patient develop cirrhosis and hepatocellular cancer.

Hepatitis C Virus (HCV): Hepatitis V Virus (HCV) structure

Characteristic features of Hepatitis C Virus (HCV)

Genetic variation of Hepatitis C Virus (HCV)

1. Genotypes of HCV are detected because of their response to treatment.
2. There are 6 genotypes with several sub-types.
   1. Type 1 genotype progress to chronicity and cirrhosis. It is less responsive to treatment.
   2. Type 2 and 3 genotypes are very responsive to antiviral treatment.
3. 75% of Americans have genotype 1, and it has subtypes 1a and 1b.
   1. 20 to 25% have genotypes 2 and 3.
   2. The smaller percentage has genotypes 4, 5, and 6.
4. Genotype 4 is more common in African countries.
5. Genotype 5 is more common in South Africa and Asia.
6. Genotype 6 is more common in Southeast Asia.

Hepatitis C Virus (HCV) genome structure:

1. It consists of N- a terminal and C-terminal.
2. There are core proteins, envelope proteins, and non-structural proteins.

HCV genome proteins

Hepatitis C Virus (HCV) is found in:

1. Blood (Serum).
2. Saliva.
3. Semen.
4. Major risk groups are:
   1. Blood transfusion.
   2. I/V drug abusers.
   3. Blood products.

Mode of the spread of Hepatitis C Virus (HCV):

1. The mode of spread is like HBV, with some differences.
   1. In 50%,  the source of the cases is not known.
2. One of the modes is blood transfusion or blood products (Now, it is rare because of screening tests available since 1987).
   1. HCV hepatitis (post-transfusion hepatitis)  is quite common in volunteer blood donors who are HBV-negative.
3. Vertical transmission from mothers to newborns is not as common as HBV infection.
4. This can spread through sexual contact, but some believe that sexual transmission is uncommon.
   1. This is seen in sex with multiple partners and unprotected.
   2. Male homosexuals are less likely to be infected as compared to HBV.
   3. It is also seen less in number in heterosexual groups.
5. This is seen in organ transplantation (before 1992).
6. This is common in I/V drug users.
7. Tattooing in an unhygienic atmosphere.
8. This may be seen in HIV patients.
9. Sharing personal items like toothbrushes or shavers that may have blood contamination.
10. It is believed that 50% of the case’s transmission mode is unknown.
11. Fetal and neonatal transmission is uncommon.
12. Passive transfer of anti-HCV antibodies is quite common.

The incubation period for Hepatitis C Virus (HCV):

1. It is 2 to 12 weeks after exposure. (other references give 2 to 52 weeks) and the average period being 7 or 8 weeks).
   1. Incubation of 2 weeks to one year is also reported.

Type of antigens and antibodies of Hepatitis C Virus (HCV):

1. HCV-Ab (IgG) appears in 3 to 4 months. and disappears in 2 years.
   1. Most cases develop HCV-IgG antibodies by 6 weeks, and the range is 5 to 30 weeks after the onset of the symptoms.
   2. The anti-HCV can be detected in acute hepatitis C during the initial phase of elevated aminotransferases activity. This antibody may never be detected in 5 to 10% of the patient with acute Hepatitis-C and anti-HCV may become undetectable after the recovery from acute hepatitis.
2. The current screening test detects antibodies against HCV.
   1. An anti-HCV screening test has been available for less than 10 years.
3. This is a unique virus in which, in acute infection, you can find an Anti-HCV antibody and also the antigen HCV-RNA.
4. Anti-HCV remains for many years. Therefore, an anti-HCV test positive indicates infection or carrier state but not infectivity or immunity.

Signs and Symptoms of  Hepatitis C Virus (HCV)

1. HCV infection is also called a silent disease.
   1. The clinical S/S are like HBV infection, but these are less severe.
   2. It is in 12% to 25% of cases of sporadic hepatitis that is not related to parenteral inoculation or sexual transmission.
2. Only 15% develop acute infection rest goes into a chronic disease.
3. Chronicity of the infection is seen in 50% to 80% of the cases (another reference says 70 to 80%).
   1. Chronicity is more common than HBV infection.
   2. It is seen in 60% of post-transfusion cases and may take 10 years.
   3. 30% of cases may develop cirrhosis in around 10 years.
   4. HCV infection may lead to chronic active hepatitis and cirrhosis.
   5. In one of the studies, chronic active hepatitis was seen in <20%, and 3% had cirrhosis.

Acute hepatitis C virus (HCV) infection

4. Fulminant hepatitis is seen in 1 to 2% of the patient.
5. HCV infection symptoms may not appear or are very mild for years.
6. Chronic infection is often asymptomatic.
7. The silent disease still causes damage to the liver.
8. The patient with the silent disease may come with chronic liver disease and may develop cirrhosis and liver cell carcinoma.
   1. It is considered a major etiology for liver cell carcinoma.

Common symptoms of Hepatitis C Virus (HCV) are :

1. Jaundice is seen in only 25% of acute hepatitis.
2. Tiredness
3. Loss of appetite
4. Nausea and vomiting
5. Abdominal pain
6. Joints pain
7. Fever
8. dark urine  and gray-colored stool
9. Ultimately patient develops jaundice
10. This chronic virus infection can lead to liver cell carcinoma.

Hepatitis C Virus (HCV) serological profile:

1. An anti-HCV screening test has been available for less than 10 years.
   1. Anti-HCV Ab (IgG) indicates:
      1. Convalescent stage.
      2. Old HCV infection.
2. Anti-HCV antibodies are IgM and IgG types.
   1. Anti-HCV antibodies:
      1. Anti-HCV Ab seen against:
         1. Core antigen.
         2. NS3 gene.
         3. NS4 antigen.
         4. NS5 antigen.

Hepatitis C Virus (HCV) antibody level in acute disease

2. 2. HCV by PCR which detects HCV-RNA, is used to confirm the diagnosis.
      1. Viral load advises quantitative PCR.
   3. Usually, SGPT (ALT) is raised in this infection and chronic cases.
   4. A negative Anti-HCV antibody does not exclude the HCV infection because seroconversion may not occur up to 6 months after exposure.
3. Usually, SGPT (ALT) is raised in infection and chronic cases.
4. A negative Anti-HCV antibody does not exclude the HCV infection because seroconversion may not occur up to 6 months after exposure.

Hepatitis C Virus (HCV) in chronic hepatitis (SGPT)

Lab diagnosis of Hepatitis C Virus (HCV)

1. Interpretation of HCV profile:
   1. Acute infection = Anti-HCV antibody will be positive.
      1. Anti-HCV by ELIZA is confirmatory.
   2. PCR can confirm the diagnosis.
      1. Qualitative PCR for HCV genome.
      2. Quantitative HCV RNA PCR.
         1. PCR (polymerase chain reaction) will show the virus’s presence in the blood.
         2. PCR is the confirmatory test for HCV infection.
         3. PCR is done in patients to start the treatment.
2. Chronic infection = Almost 85 % shows Anti-HCV antibody.
   1. Positive HCV-Ab indicates present or past infection.
   2. Table showing HCV markers in various conditions:
      

      Test	Normal	Early infection	Acute	Chronic	Carrier	Recovery
      Anti-HCV	Negative	Negative	+	+	+	+
      PCR	Negative	+	+	+	+	Negative

The complication of Hepatitis C Virus (HCV) infection:

1. There are chances for:
2. Fulminant hepatitis is seen in 1 to 2% of the patients.
3. Cirrhosis is seen in 5% of the cases.
4. Liver failure.
5. Liver cancer risk is 15%.
6. HCV infection is unlike HBV because this gives rise to more than 60% as a chronic disease.
   1. (some references say chronicity is from 50% to 80%)

Treatment Options for Hepatitis C Virus (HCV):

1. Alfa-interferon alone. It gives benefits to <50% of the cases. Relapse is common at the stop of the treatment.
   1. Interferon (IFN-α2, 3,000,000U) 3 doses per week is subcutaneously given for one year.
   2. It prevents the development of liver cell carcinoma.
   3. Monitor with SGPT, SGOT, and PCR for HCV.
   4. Retreatment can be given in  50 to 80% of the relapse cases.
2. Type 2 and 3 genotypes positive patients are three times more sensitive to antiviral treatment like alpha-interferon or combination therapy, with the addition of Ribavirin.
3. Alfa-interferon with  Ribavirin as combination therapy.
4. The latest therapy can cure 95% of patients.
5. To label, that patient is cured when for three months PCR HCV is negative after the completion of the treatment.

Preventions of Hepatitis C Virus (HCV):

• There is no vaccination available for HCV.
• Proper testing of the blood donors for transfusion for HCV has decreased the incidence.

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