CPT® Code 87149

Culture, typing; identification by nucleic acid (DNA or RNA) probe, direct probe technique, per culture or isolate, each organism probed

The CPT® Code 87149 refers to a laboratory procedure that involves the culture and identification of microorganisms, such as bacteria, viruses, fungi, or parasites, using a specific technique known as nucleic acid probe testing. This method allows for the definitive identification of the microorganism at the genus or species level. Initially, a culture is performed to obtain a presumptive identification of the microorganism, which is a separate and reportable procedure. Once this initial identification is established, additional cultures may be conducted to refine the identification process further. In the context of CPT® Code 87149, a direct probe technique is employed. This involves the use of a lysate, which is a solution that ruptures the cells of the cultured organism to release their nucleic acids, either DNA or RNA. The lysate is then introduced into a sample well, while the cultured organism is placed on a test slide. The test slide is subsequently immersed in the lysate and incubated using robotic technology to ensure precise conditions for the reaction. Following this incubation, a DNA or RNA probe, which consists of laboratory-prepared complementary strands of nucleic acid specific to the target organism, is added to the test well. If the cultured cells contain the corresponding nucleic acids, the probe will bind to them, forming a double-stranded complex or hybrid. This binding indicates the presence of the specific genus or species being tested. The detection of this binding is often facilitated by probes that are labeled with chemical fluorescence, with a positive result indicated by a change in color. It is important to report a direct probe for each culture or isolate probed using this technique, as well as for each organism that is identified. This procedure is crucial for accurate microbiological diagnostics and plays a significant role in guiding appropriate treatment options for infections caused by these microorganisms.