CT Case 051
A 40-year-old male presents in a shocked state with less than 24 hours of perianal and perineal pain
He has a past history of T2DM and obesity.
A CT abdomen is performed
Describe and interpret the CT scan
CT interpretation
The case demonstrates perianal abscess with associated Fournier gangrene.
There is a perianal collection below the level of the levator ani muscle.
There are multiple locules of air seen in the perineum and right scrotum which represent Fournier’s gangrene.
There is also smooth enhancement of the wall of right hemiscrotum and air foci within the scrotal cavity, this is due to infection involving the scrotum.
Though it can be clinically diagnosed, CT can be helpful in doubtful cases and also in looking for the primary cause and extent of infection. Typically the testis are spared from destruction due to their arterial supply from the abdominal aorta.
Hydrocoeles are often seen due to reactive changes, though they can turn into collections.
Clinical Pearls
Fournier gangrene is necrotising fasciitis of the perineum. It begins abruptly with severe pain and can spread rapidly to the anterior abdominal wall and the gluteal muscles.
Fournier gangrene carries an even higher mortality rate than other necrotising soft tissue infections, with a mortality rate sitting at 22-40% even with optimal therapy.
Anorectal, genitourinary, and traumatic infections are the most common causes of Fournier’s gangrene.
This patient was managed with extensive and repeated debridement and wash out of the perianal, perineal and right inguinal region.
He also had a defunctioning sigmoid loop stoma, this is stoma formation so that bowel contents can be diverted temporarily to prevent wound contamination.
Perioperative fluid resuscitation, vasopressor support, antibiotics, and nutritional support are also of major importance in management of the disease.
References
- Barns M. Fournier gangrene. LITFL
- Cadogan M. Jean-Alfred Fournier (1832-1914). LITFL
- Levenson RB, Singh AK, Novelline RA. Fournier gangrene: role of imaging. Radiographics. 2008 Mar-Apr;28(2):519-28
- Laucks SS 2nd. Fournier’s gangrene. Surg Clin North Am. 1994 Dec;74(6):1339-52
TOP 100 CT SERIES
Sydney-based Emergency Physician (MBBS, FACEM) working at Liverpool Hospital. Passionate about education, trainees and travel. Special interests include radiology, orthopaedics and trauma. Creator of the Sydney Emergency XRay interpretation day (SEXI).
Provisional fellow in emergency radiology, Liverpool hospital, Sydney. Other areas of interest include paediatric and cardiac imaging.
Emergency Medicine Education Fellow at Liverpool Hospital NSW. MBBS (Hons) Monash University. Interests in indigenous health and medical education. When not in the emergency department, can most likely be found running up some mountain training for the next ultramarathon.
Dr Leon Lam FRANZCR MBBS BSci(Med). Clinical Radiologist and Senior Staff Specialist at Liverpool Hospital, Sydney