[Morphological features of the pulmonary sequestration]

Area of Science:

• Pulmonary Medicine
• Pathology

Context:

• Pulmonary sequestration is a rare congenital lung malformation characterized by non-functional lung tissue with systemic arterial supply.
• Accurate diagnosis, especially for intra-lobar sequestration, relies on specific clinical and imaging findings.
• Understanding the morphological and histochemical features is crucial for differentiating types and guiding treatment.

Purpose:

• To investigate the utility of histochemical (Movat's pentachrome, Verhoeff) and immunohistochemical (CK7, TTF1) techniques in characterizing pulmonary sequestration.
• To identify key pathological changes associated with both intra-lobar and extra-lobar pulmonary sequestration.
• To correlate imaging findings with histopathological features for improved diagnostic accuracy.

Summary:

• Eight cases (four intra-lobar, four extra-lobar) of pulmonary sequestration were analyzed using Movat's pentachrome, Verhoeff, CK7, and TTF1 staining.
• Consistent findings included parenchymal inflammatory distortion with collagenization, Bronchus-Associated Lymphoid Tissue (BALT) hyperplasia, and pleuritis.
• Movat's pentachrome effectively identified the systemic artery and parenchymal alterations, while CK7 highlighted parenchymal damage, and TTF1 showed variable expression linked to inflammation and PII hyperplasia.

Impact:

• This study demonstrates the value of specific histochemical and immunohistochemical markers in the diagnosis and characterization of pulmonary sequestration.
• The findings can improve the pathological identification of sequestration, aiding in clinical management and understanding of the disease.
• Enhanced diagnostic tools contribute to better patient outcomes by enabling precise diagnosis of this rare condition.