CPT® Code 81228

1. Indications

The cytogenomic analysis described by CPT® Code 81228 is indicated for the evaluation of various genetic conditions and abnormalities. The following conditions and symptoms warrant the use of this testing:

• Idiopathic Mental Retardation - This refers to cases of intellectual disability where no clear cause can be identified, making genetic testing essential for diagnosis.
• Developmental Delay - Individuals exhibiting delays in reaching developmental milestones may benefit from this analysis to uncover underlying genetic factors.
• Autism Spectrum Disorders - The testing can help identify chromosomal abnormalities that may be associated with autism, aiding in understanding the genetic basis of the disorder.
• Multiple Congenital Anomalies - For individuals presenting with various congenital defects, cytogenomic analysis can provide insights into potential genetic causes.

2. Procedure

The procedure for conducting cytogenomic analysis using CPT® Code 81228 involves several detailed steps, which are outlined below:

• Step 1: Sample Collection - The first step involves obtaining a biological sample from the patient. This sample can be derived from various sources, including peripheral blood, skin, products of conception (such as umbilical cord or cord blood), saliva, buccal swabs, or primary cultured fibroblasts. In prenatal cases, samples may be collected via amniocentesis or chorionic villus sampling (CVS).
• Step 2: DNA Amplification and Preparation - Once the sample is collected, the DNA is extracted and amplified. In the BAC microarray analysis, a short segment of the human DNA is inserted into a bacterial artificial chromosome, which allows for the sequencing of the genome. For the oligo-based CGH, the test DNA and a reference DNA sample are labeled with different fluorophores.
• Step 3: Hybridization - The labeled DNA samples are then hybridized to probes that are derived from known genes and non-coding regions of the genome. This hybridization occurs on a glass slide, where the DNA samples bind to their respective probes.
• Step 4: Fluorescence Measurement - After hybridization, the fluorescence intensity of the test DNA is compared to that of the reference DNA. This measurement allows for the calculation of the ratio of fluorescence intensity, which is crucial for identifying copy number changes at specific genomic locations.
• Step 5: Data Analysis - The final step involves analyzing the data obtained from the fluorescence measurements to identify any chromosomal abnormalities or copy number variants that may be present in the patient's genome.

3. Post-Procedure

After the cytogenomic analysis is completed, the results are interpreted by a qualified geneticist or genetic counselor. The findings can provide critical insights into the genetic basis of the patient's condition, guiding further clinical management and family counseling. Patients may require follow-up consultations to discuss the implications of the results, potential treatment options, and any necessary additional testing. It is also important to consider that the turnaround time for results may vary based on the complexity of the analysis and the laboratory's processing capabilities.