ferruginous bodyA fibre clad in protein, mucopolysaccharides, and iron (hence the adjective ferruginous). While ferrugious bodies are classically associated with asbestos, fibres on which such bodies develop include other elongated fibres that cannot be digested by macrophages—e.g., aluminium, aluminium oxide, carbon, diatomaceous earth, kaolite, mica, mullite, iron, fibreglass, rutile, sheet silicates and talc.
Ferruginous body evaluation
• Light microscopy—Perl’s stain of routine paraffin sections; thick (20µ) unstained sections.
• Phase contrast light microscopy.
• Scanning electron microscopy.
• Transmission electron microscopy.
The finding of ferruginous bodies only proves exposure, not disease. In tumour cases, three blocks of tissue from the contralateral side should be taken.