Broncholithiasis mimicking metallic projectiles at autopsy: a forensic diagnostic pitfall in putrefied bodies

We report an autopsy case in which broncholithiasis mimicked retained ballistic projectiles in a putrefied body. A medico-legal autopsy was performed on a 76-year-old male found in an advanced state of putrefaction. Macroscopic examination during autopsy revealed small, stony intrapulmonary nodules raising suspicion of retained pellets. Whole-body post-mortem computed tomography (PMCT) allowed us to further characterize these elements. The structures were subsequently analyzed using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDS) to determine their elemental composition. PMCT demonstrated multiple hyperdense micronodules within the right upper lobe, arranged in a linear endobronchial pattern without metallic artifacts, strongly suggesting a calcified biological origin. SEM-EDS analysis revealed a predominance of calcium and phosphorus, with no evidence of metallic elements typically associated with ballistic materials. These findings and histopathological examination confirmed the diagnosis of broncholithiasis. Broncholithiasis may closely mimic retained ballistic fragments at the macroscopic level in decomposed bodies, representing a significant forensic diagnostic pitfall. While PMCT is key to orienting the diagnosis, this work highlights the value of a multimodal approach combining post-mortem imaging, histopathology, and elemental microanalysis to provide definitive chemical confirmation and prevent misinterpretation of the cause and manner of death.