Granulomatous prostatitis

Granulomatous prostatitis is a nodular form of chronic prostatitis. It is usually diagnised by biopsy.

Pathology

Causes

• idiopathic
• infection
• iatrogenic: (BCG,post radiation)
• systemic disease such as
  • sarcoidosis 
  • autoimmune diseases

Radiographic features

General features

Often there is no definite ultrasound or MRI finding that allows a specific diagnosis of granulomatous prostatitis to be made, or differentiation from prostatic carcinoma ².

Widening of the prostatic urethra however may be a useful feature in differentiation from prostatic carcinoma ¹.

Ultrasound 

May be seen as a hypoechoic nodule (~70%) or diffuse hypoechoic peripheral zone (~30%)

MRI

Three morphological MRI patterns have been described which are diffuse (most common), nodular, and cystic with mural nodule ³.

Signal characterisitcs include 

• T2 - hypointense
• C+ (Gd) - no enhancement following Gd-DTPA