Nonspecific simple eosinophilic granulomatous prostatitis with eosinophilia in peripheral blood. A case report

Nonspecific simple eosinophilic granulomatous prostatitis is extremely rare and in the present paper, the first case showing eosinophilia in the peripheral blood is reported. The patient was a 55-year-old Japanese man who was admitted because of difficulty in urination over a period of several years. The laboratory findings revealed marked eosinophilia (36%) in the peripheral blood, but the patient's past history showed neither bronchial asthma nor any allergic tendency. Transurethral resection of the prostate was performed and the histopathologic findings revealed a picture of non-caseating granulomatous prostatitis with massive eosinophilic infiltration without fibrinoid necrosis or vasculitis. Fragments of the prostatic urethra also showed the same findings. No fungus, bacterium or parasite was found. Although remnants of smooth muscle fibers were noted in the granulomas, neither immunoglobulins nor complement components could be demonstrated, and the etiology remained undetermined.