Myospherulosis of nose and sinuses
This condition was first described in 1969 in 6 Africans who presented with nodular swellings inside the nasal cavity. These swellings were painful and develop in relation to skeletal muscle. Possibly ? iatrogenic.
This lesion consists of fibrous and inflammatory granulomatous tissue in which there are cyst like spaces lined by flattened foam cells presumed to be histiocytes. Some of these spaces contain clusters of rounded bodies slightly larger than red blood cells and are surrounded by a thin refractile membrane. Neither the cyst like spaces or their contents stain with usual fungal stains.
Almost all patients had history of previous operative procedures prior to the first histological identification of the lesion. A common feature identified in these patients was the use of gauze packing with petrolactum based antibiotics. Thus it could be considered to be due to reaction to the ointment. The conclusion was that the spherules were red cells modified by the petrolactum based antibiotics.
This lesion should be differentiated from fungal lesions.