Hepatitis C is a viral infection caused by the hepatitis C virus. A mildly symptomatic chronic illness is observed in the majority of cases. But because of its risk of progression to cirrhosis and hepatocellular carcinoma which can both be life-threatening, timely detection is necessary. Detection of specific antibodies and viral RNA in serum is required to confirm the diagnosis.
With over 170 million infections caused by hepatitis C virus (HCV) worldwide, hepatitis C infection remains one of the largest public health concerns due to its rather important place in the etiology of chronic liver disease  . HCV is transmitted through blood products (through intravenous drug use and needle-sharing) and via the sexual route, while blood transfusions have been an important source of HCV until the introduction of routine screening of blood    . Vertical transmission, on the other hand, is the principal mode of virus acquisition in children, and approximately 8000 new cases of hepatitis C infection are reported in the United States every year . The primary reason for such a high number of cases globally is the insidious nature of the infection, as up to 85% of infected individuals develop a stable chronic infection  . The incubation period of hepatitis C infection ranges from 14-180 days, after which one of the following clinical scenarios can be observed   :
The diagnosis of a hepatitis C infection based solely on clinical criteria is difficult, especially in mildly symptomatic chronic carriers. For this reason, a detailed patient history is mandatory during the workup, as physicians can assess risk factors - risky sexual intercourse, intravenous drug abuse or even recent tattooing, as well as the onset and progression of symptoms. When clinical suspicion of viral hepatitis is supported by data obtained during history and a physical examination, an extensive laboratory workup is necessary. Firstly, a complete biochemical profile is drawn, comprised of serum electrolytes, a complete blood count, liver function tests (alanine and aspartate aminotransferases, or ALT and AST), renal parameters (blood urea nitrogen and creatinine), and bilirubin levels. Liver enzymes are usually elevated up to 10 times the normal values, in which case, testing for viral hepatitis should be carried out  . In the setting of hepatitis C, serology testing for anti-HCV IgM and IgG antibodies is the cornerstone of the diagnosis of both acute as well as chronic infections, and IgM titers can be quite high even in chronic carriers    . Antibodies cannot be detected for at least 7 weeks after viral acquisition, until the process of seroconverision occurs . However, detection of viral RNA in blood can be made through polymerase chain reaction (PCR) testing much earlier, which is also one of the most important tools for long-term monitoring and response of individuals to therapy     . If PCR detects viral RNA in blood, the diagnosis can be made with certainty. It must be noted that coinfections with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) are rather common in HCV patients, which is why testing for both of these infections through appropriate serological (anti-HIV antibodies and HBsAg/HBeAg/anti-HBc antibodies) and molecular (isolation of viral RNA through PCR) methods is imperative    .