An unusual case of extensive epididymotesticular malakoplakia in a diabetic patient.

A 67-year-old Saudi man with poorly controlled diabetes-mellitus underwent orchiectomy for a painful left testicular swelling that did not respond to antibiotics. Clinical diagnosis was testicular malignancy. Histologic workup demonstrated extensive involvement of the testis and epididymis by diffuse infiltrate of large histiocytes with eosinophilic granular cytoplasm and numerous Michaelis-Gutmann bodies, which were diagnostic of malakoplakia. Very rarely, malakoplakia has been described in association with diabetes mellitus. Such an extensive malakoplakia occurring at an unusual site in association with systemic illness lends support to the view that a compromised immune status could be etiologically important in malakoplakia. We present this case to highlight the importance of diagnosing malakoplakia when it occurs at unusual locations. We also explore the role of diabetes mellitus in the pathogenesis of malakoplakia and compare the relationship between malakoplakia and xanthogranulomatous inflammation, which are closely related to each-other on both clinical and morphologic grounds.