Eosinophil Granule Major Basic Protein, Tissue Biopsy

Casandra

Casandra Test Code AR13483Version 1 (DRAFT)

Performing Lab

Lab ARUP LaboratoriesLab Test ID 2010921CPT Codes 88305, 88341, 88342

Eosinophil Granule Major Basic Protein, Tissue Biopsy

Also known as: EGMBP TIS

Clinical Use

Order Test

Use

This test is utilized to identify eosinophil activity and involvement in tissues or organs suspected to have eosinophil-related pathophysiology. It employs indirect immunofluorescence to detect cellular localization and extracellular deposition of eosinophil granule core protein (major basic protein 1 [eMBP1]) and/or eosinophil granule matrix protein (eosinophil-derived neurotoxin [EDN]). The results assist in diagnosing eosinophilic esophagitis or other eosinophil-related inflammation as part of the eosinophilic gastrointestinal disease spectrum.

Special Instructions

Turnaround time may be prolonged for specimens submitted in formalin or as formalin-fixed, paraffin-embedded tissue blocks or slides. Clients are encouraged to contact the Immunodermatology Laboratory to discuss specific clinical information that might expedite testing and results. Additional stains will be performed if formalin-fixed or FFPE tissues are submitted, and additional charges may apply for multiple specimens.

Limitations

The results of eosinophil granule major basic protein testing may not provide a definitive diagnosis of eosinophilic esophagitis or other eosinophil-related inflammation on their own. Extracellular eMBP1 deposition, though often observed, is not established as a diagnostic feature. Furthermore, small tissue specimens may lead to false positives due to processing artifact. Factors such as patient treatment status and tissue biopsy location can affect results, and findings should be correlated with clinical presentation and histopathological examination of formalin-fixed tissue.

Test Details

New York Approved