CPT® Code 87523

Infectious agent detection by nucleic acid (DNA or RNA); hepatitis D (delta), quantification, including reverse transcription, when performed

The CPT® Code 87523 refers to a laboratory test designed for the detection and quantification of the hepatitis D (delta) virus, utilizing nucleic acid techniques. This procedure specifically targets the presence of the hepatitis D virus (HDV) in serum or plasma samples through a method known as real-time polymerase chain reaction (RT-PCR). Hepatitis D is a unique viral infection that can only occur in individuals who are also infected with the hepatitis B virus (HBV), as it relies on HBV for its replication. The hepatitis D virus is classified as a mutated RNA virus and is distinct from other hepatitis viruses such as A, B, and C. The presence of HDV can lead to severe liver complications, particularly in patients with existing hepatitis B infections, potentially resulting in conditions such as fulminant acute hepatitis, cirrhosis, and hepatocellular carcinoma. The testing process involves treating the viral RNA to protect it from degradation, followed by reverse transcription, which converts the RNA into complementary DNA (cDNA). This cDNA is then amplified using specific primers that bind to the target nucleic acid, allowing for the measurement of fluorescence at each cycle of the PCR process. The quantification of the generated DNA is crucial for monitoring the progression of the disease and assessing the patient's response to treatment.