Hypereosinophilic syndrome: case report and morphometric study

Area of Science:

• Hematology
• Cell Biology
• Pathology

Background:

• Hypereosinophilic syndrome (HES) is a group of disorders characterized by persistent overproduction of eosinophils.
• Understanding the cellular morphology and behavior of eosinophils in HES is crucial for diagnosis and treatment.

Observation:

• A patient presented with a severe eosinophil count (273 x 10(9) cells/L) but only mild clinical symptoms affecting skin, lungs, and heart.
• Morphometric analysis compared the patient's eosinophils to those of healthy individuals.

Findings:

• Patient eosinophils exhibited significantly increased cell size and surface area.
• Mitochondrial volume and surface area were elevated, with more mitochondrial profiles per section.
• Eosinophil granules showed a marked reduction in total volume, indicating degranulation.

Implications:

• The findings suggest inappropriate and potentially orderly eosinophil activation and degranulation in HES.
• Morphometry provides valuable quantitative data for assessing cellular changes in hematological disorders.
• This cellular-level insight may explain the discrepancy between high eosinophil counts and mild symptoms.