CPT® Code 88319

Special stains, including those for enzyme constituents, are critical laboratory procedures used to identify specific enzymes within blood, bone marrow, or tissue samples. These stains are particularly valuable in the field of cytopathology, as they assist in the identification of abnormal cells and provide additional diagnostic insights regarding cells that may appear normal under standard examination. The process begins with the preparation of a fresh specimen, which is smeared onto a glass slide. To ensure that the specimen adheres properly, a fixative is applied. Following this, the slide undergoes a washing step to remove any excess fixative before the staining reagent is introduced. After the staining reagent is applied, the slide is washed again to eliminate unbound stain, and counterstaining may be performed to enhance the visibility of cellular details. For quality control, a control sample of normal cells is stained concurrently, allowing for comparison and validation of the results. The outcome of the staining process is assessed based on the presence or absence of enzyme activity, which is indicated by the intensity and distribution of the stain across various cellular constituents. Common examples of enzyme stains include tartrate resistant acid phosphatase stain, myeloperoxidase (MPO) stain, and chloroacetate esterase stain, each serving specific diagnostic purposes in the evaluation of hematological and tissue samples.