The induction of human myospherulosis in experimental animals.

Tissue lesions similar to those in human myospherulosis were reproduced in experimental animals and studied by light and electron microscopy. The lesions were produced by the use of petrolatum-based antibiotic ointments. These ointments, which are marketed as nonsterile products, are similar to those used for hemostatic packing in otolaryngologic surgery. To date, use of these ointments has been reported to precede the finding of human paranasal sinus myospherulosis. The exact nature of the structures of myospherulosis remains unknown. The experimental evidence strongly suggests that they can be iatrogenically produced by the use of these nonsterile ointments.