Pulmonary abnormalities in mice with paracoccidioidomycosis: a sequential study comparing high resolution computed...

Area of Science:

• Mycology
• Pulmonology
• Medical Imaging

Background:

• Paracoccidioidomycosis (PCM) is a significant endemic fungal infection of pulmonary origin.
• Previous studies have not utilized imaging for follow-up of pulmonary lesions in experimental PCM.
• This research investigates lung lesion patterns in a mouse model of PCM using advanced imaging techniques.

Purpose of the Study:

• To define lesion patterns, topography, and intensity in experimentally induced PCM in mice.
• To comparatively analyze High Resolution Computed Tomography (HRCT) findings with histopathologic parameters.
• To establish HRCT as a viable tool for evaluating pulmonary damage in experimental PCM.

Main Methods:

• Male BALB/c mice were intranasally inoculated with Paracoccidioides brasiliensis (Pb) conidia or PBS.
• High Resolution Computed Tomography (HRCT) was performed every four weeks to assess pulmonary lesions and lung density.
• Histopathology and histomorphometry were used for detailed analysis of lung tissues.

Main Results:

• Three distinct lesion patterns were identified: nodular-diffuse, confluent, and pseudo-tumoral.
• Lesions predominantly occurred around the hilus and in the left lung, with HRCT showing peri-bronchial consolidations and increased lung density.
• Histopathology confirmed HRCT findings, correlating consolidation with granulomatous reactions and nodules with compact granulomas.

Conclusions:

• Conventional HRCT is a valuable tool for evaluating and quantifying pulmonary damage in experimental mouse PCM.
• The study design minimizes animal sacrifice, enabling a more rational approach to studying human lung disease.
• HRCT facilitates monitoring treatment efficacy in experimental PCM models.