A CASE OF MYOSPHERULOSIS OCCURRING IN THE PERIRENAL ADIPOSE-TISSUE

The authors report a case of spontaneous myospherulosis that developed in the right perirenal adipose tissue, presented like an abcess, in a n 82-year-old man of the A, Rh + blood group. The patient had a histor y of chronic lymphocytic leukaemia. Fine needle aspiration and histolo gical examination of the renal cyst allowed the observation of 4- to 7 -mu m spherules (or endobodies) enclosed in saccular structures (or pa rent bodies) and accompanied by a foreign body-type response. The wall s of the parent bodies were negative for PAS, Gomori's methenamine sil ver and Giemsa's stain. Immunohistochemical study was positive with an ti A antibody specific of A1/A2 blood group and with anti glycophorin A antibody. The authors reviewed the literature concerning this rare l esion: it usually occurs in subcutaneous fat or in the paranasal sinus es, nose and middle ear but, up to now, no previous case has ever been reported in the urinary tract. The only case of visceral myospherulos is previously reported occurred in a cystic teratoma of the ovary. The 'reported case' is also peculiar by the unusual thickness of the pare nt bodies. The authors also discuss the mechanism of the disease and s uggest that, in the present observation, myospherulosis could have bee n induced by the rupture of a preexisting cyst in the perirenal adipos e tissue.