Neonatal prostatic utricle abscess / cyst

PatientThe patient subsequently underwent laparotomy and drainage of the lesion, which was purulent. Histology confirmed an abscess with no malignant features. Hydronephrosis subsequently resolved.

FinalThe final diagnosis was an infected giant prostatic utricle cyst / abscess. Giant utricle cysts are rare occurrences in neonates¹, particularly at this size, with infected utricle cysts even less common. UTI is the most likely cause of the initial infection, and the spectrum of findings overlaps with neonatal prostatic abscesses, although there is a paucity of cases in the literature².

Soft tissue density centred over the pelvis suspicious for a pelvic mass.

Nasogastric tube tip projects at the gastric antrum. Indwelling catheter within the urinary bladder.Cardiothymic silhouette is normal.  Lungs are clear without evidence of nodule or mass.  No pleural effusion or air leak.No pathologically dilated loops of large or small bowel. Gas seen in the rectum.No definite destructive osseous lesion demonstrated on this radiograph.

Adrenal glands appear unremarkable bilaterally, with expected positions superior to the kidneys.Right kidney measures 5.5cm.  Left kidney measures 4.7 cm.Bilateral mild pelvicalyceal dilatation (AP renal pelvic diameter right 11 mm, left 10 mm with prominence of the calyces) and dilatation of both ureters to the level of the pelvis, left ureteric diameter of 5 mm, right ureteric diameter 5 mm (measured distally).   

Well-defined, encapsulated, multiloculated mass posterior to the bladder with no internal vascularity and mobile internal low level echoes suggesting predominately cystic contents.  Dimensions Dimensions 51mm craniocaudal x 34 mm AP x 33mm transverse.   This mass appears to be displacing the rectum to the left, and abuts anterior aspect anterior sacrum/coccyx. 

Bladder volume approximately 60ml with the bladder seen anterior to and extending superior to the pelvic mass which has mass effect on the inferior aspect of bladder.  Small amount of echogenic dependent debris within the bladder.   

IMPRESSION1) Multiloculated cystic presacral mass with displacement of the rectum.  2) Bilateral hydronephrosis and hydroureter.   BladderBladder extends superior to the pelvic mass and the mass appears to compress the inferior aspect of bladder. Low level mobile debris within the bladder.

• Multilobulated, multiseptated, 29 x 42 x 59 mm pelvic mass.  Centrally the cystic areas demonstrate a density of approximately 30 HU. 

• Septated components are enhancing.  No calcification. 
• Epicentre of the lesion lies just anterior to the sacral vertebral bodies, with subtle scalloping of L5 – S3.
• Posteriorly, anterior to S3, the posterior border of the mass is less conspicuous.  No definite foraminal widening demonstrated.
• Caudally, the mass extends down through the rectovesicular recess, inferior to the level of the pubic symphysis just deep to the perineum, without evidence of infiltration through it. Mass displaces the rectum to the left side without obstructing it. 
• Anterior to the mass lies the collapsed urinary bladder. 
• Superiorly the mass extends to an S1 level. Mass effect upon the bilateral ureters is causing bilateral, upstream hydroureter and hydronephrosis. Normal renal cortical thickness and enhancement demonstrated bilaterally.