Immunodiffusion; gel diffusion, qualitative (Ouchterlony), each antigen or antibody
CPT4 code
Name of the Procedure:
Immunodiffusion: Gel Diffusion, Qualitative (Ouchterlony)
Summary
Immunodiffusion is a laboratory technique used to detect and identify antigens and antibodies in a sample. The Ouchterlony method involves placing samples in a gel and observing the formation of precipitin lines, which indicate antigen-antibody interactions.
Purpose
This procedure helps in diagnosing infections, autoimmune diseases, and certain other medical conditions by identifying specific antigens or antibodies present in the patient's sample.
Indications
- Unexplained chronic infections
- Autoimmune diseases
- Allergic reactions
- Monitoring therapeutic antibody levels
Preparation
Generally, no special preparations are required for the patient. However, it is advised to inform the healthcare provider about any medications being taken, as certain drugs may affect the results.
Procedure Description
- Agar gel is prepared and poured into a petri dish or similar container.
- Wells are cut in the gel for the antigen and antibody samples.
- Antigen samples are placed in the outer wells, and antibody samples are placed in a central well.
- The gel is incubated, allowing the antigen and antibody to diffuse towards each other.
- Precipitin lines form where antigens and antibodies meet, indicating a reaction.
Tools and Equipment:
- Agar gel
- Petri dishes or plates
- Micro-pipettes for sample placement
No anesthesia or sedation is required for this laboratory procedure.
Duration
The procedure typically takes several hours to a few days, depending on the diffusion rate and the conditions required for precipitin line formation.
Setting
The procedure is carried out in a clinical laboratory.
Personnel
Medical laboratory technicians or technologists perform the procedure under the supervision of a clinical pathologist or microbiologist.
Risks and Complications
There are no direct risks to the patient as the procedure is performed on extracted samples. However, incorrect sample handling or contamination can lead to inaccurate results.
Benefits
- Accurate identification of specific antigens or antibodies.
- Helps in diagnosing various medical conditions.
- Quick and relatively inexpensive.
Recovery
No recovery time is needed as it is a non-invasive, laboratory-based procedure.
Alternatives
Enzyme-Linked Immunosorbent Assay (ELISA)
- More sensitive but also more expensive.
Western Blot
- Highly specific but more technically demanding and time-consuming.
Radioimmunoassay (RIA)
- Highly sensitive but involves the use of radioactive materials.
Patient Experience
The patient will not experience anything unusual as the procedure is conducted on blood samples or other biological specimens taken previously. There is no pain or discomfort associated with the immunodiffusion process itself.