CASE 9116 Published on 24.02.2011

Ureteral obstruction complicating Crohn disease

Section

Abdominal imaging

Case Type

Clinical Cases

Authors

Tonolini M, Crespi M*
Department of Radiology and *General Surgery, “Luigi Sacco" Hospital – Milan (Italy)

Patient

19 years, female

Categories
Area of Interest Abdomen, Urinary Tract / Bladder, Small bowel ; Imaging Technique CT
Clinical History
A young patient was admitted to the Emergency Department with characteristic clinical picture and laboratory abnormalities of an acute exacerbation of her known Crohn disease. One year earlier, she had undergone surgery with segmental ileal resection. Beyond intestinal and systemic complaints, the patient denied symptoms related to the urogenital system.
Imaging Findings
Abdominal radiographs showed a gasless right hemiabdomen, moderately distended small bowel loops in the pelvic area without obstructive gas-fluid levels, and some gas in the left colon and rectosigmoid.
Further investigation included contrast-enhanced abdominopelvic CT, performed without any bowel preparation or distension. In the right iliac fossa, recurrent ileocaecal Crohn disease was diagnosed with convergent loops indicating enteric fistulisation. Peritoneal fluid was present in the pelvis.
Right hydronephrosis (with preserved renal parenchymal thickness and enhancement) was noted, with upper lumbar ureteral dilatation and progressive thinning when reaching an abscess collection abutting the retroperitoneal fascial plane.
Double-J ureteral catheter was placed preoperatively, and the patient underwent ileocecal resection with ureterolysis.
Postoperative CT at hospital discharge, completed with excretory-phase acquisition, revealed partial resolution of the right hydronephrosis with persistent dilatation of upper calyces and renal pelvis; ureteral double-J catheter was still in place.
The patient did well postoperatively and the ureteral stent was removed.
Discussion
Urinary tract involvement, diagnosed in 4.3% of Crohn disease patients, is most common in females and may be clinically unsuspected due to minimal urogenital symptoms masked by intestinal complaints [1, 2].
Besides common manifestations such as cystitis and urolithiasis, unusual urologic complications include entero-vesical fistulas and ureteral obstruction [2, 3].
Obstructive uropathy represents a rare extraintestinal manifestation of Crohn disease and has been reported to involve 1.9% of patients in a large series [4-6].
Hydro-ureteronephrosis is caused by transmural bowel inflammation through mechanisms of compression, fibrosis or fistulisation [4]. Ureteral obstruction is by far more common on the right side (because of the right-sided ileum) and, as confirmed by the presented case, is highly associated with fistulising ileocolic disease and presence of an inflammatory mass [1, 5].
To avoid a delayed diagnosis and to ensure correct Crohn disease assessment, symptoms relating to the urinary tract such as recurrent infections, fever, dysuria, pneumaturia and fecaluria should be clinically addressed [1].
In the past urinary tract abnormalities were usually assessed with intravenous urography and renal scintigraphy. Currently, collecting systems dilatation is usually detected initially with ultrasound and further investigated by CT or MRI.
During imaging evaluation of Crohn disease with all modalities (ultrasound, CT and MRI) detection of hydronephrosis requires focused attention and careful reporting, since this uncommon feature may lead to altered surgical management.
Most patients are treated surgically, usually with ileocolic resection and ureterolysis; positioning of ureteral double-J catheter is minimising the risk of ureteral damage during surgery [1,3,5].
Differential Diagnosis List
Right-sided hydronephrosis due to ureteral obstruction by Crohn disease
Crohn disease acute relapse
Ureteropelvic junction obstruction
Ureteral fibrosis
Final Diagnosis
Right-sided hydronephrosis due to ureteral obstruction by Crohn disease
Case information
URL: https://www.eurorad.org/case/9116
DOI: 10.1594/EURORAD/CASE.9116
ISSN: 1563-4086