TOACS FCPS Station · Barium Studies in Crohn Disease

📷 Barium Study (Small Bowel Follow‑Through)

Barium study showing skip lesions, stricture, and cobblestoning in Crohn disease

Figure 1 · Small bowel barium study · Crohn Disease – Skip Lesions & Stricture

🔍 Key radiographic features:

✓ Skip lesions – areas of normal bowel interspersed with diseased segments
✓ String sign – long, narrow stricture (ileal) from spasm/fibrosis
✓ Cobblestoning – thickened, nodular mucosa with deep fissures
✓ Fistula – abnormal connections (enterocutaneous, enteroenteric)
✓ Ileal involvement – sagmental involvment. most common site (terminal ileum)

📋 Clinical scenario (examiner prompt)

A 15‑year‑old boy presents with chronic diarrhea, right lower quadrant abdominal pain, and weight loss over the past 6 months. He has a perianal fistula and poor growth. A small bowel barium study is performed. The image shows skip lesions, a string sign in the terminal ileum, and cobblestoning of the mucosa.

Chronic diarrhea String sign Skip lesions Perianal fistula

🧑‍⚕️ Examiner tasks · TOACS

1. Identify the diagnosis from the barium study and clinical context.

2. Describe the radiographic findings (skip lesions, string sign, cobblestoning).

3. Explain the pathophysiology (transmural inflammation, fibrosis).

4. Discuss management (nutritional therapy, biologics, surgery for stricture).

⚠️ Key concept: The string sign on barium study in the terminal ileum is a classic finding of Crohn disease, representing a fibrostenotic stricture. Skip lesions and cobblestoning reflect the transmural, discontinuous nature of the disease.

🎯 Expected answers (for examiners)

• Diagnosis: Crohn disease (ileal stricturing phenotype – Montreal B2)
• X‑ray findings: String sign (terminal ileal stricture), skip lesions, cobblestoning
• Pathophysiology: Transmural inflammation → fibrosis → stricture
• Management: Exclusive enteral nutrition (EEN) or steroids for inflammation; surgery (strictureplasty/resection) if symptomatic obstruction

⚡ Quick FCPS‑style MCQ

The string sign on barium study in the terminal ileum is characteristic of:

A. Ulcerative colitis B. Crohn disease (fibrostenotic stricture) C. Celiac disease D. Tuberculosis

📌 Topic summary ·

Definition
Transmural, skip lesions, granulomas

String sign
Fibrostenotic stricture (terminal ileum)

Skip lesions
Discontinuous inflammation

Cobblestoning
Nodular mucosa with deep fissures

Perianal disease
Fistulas, abscess, skin tags

Treatment
EEN, biologics, surgery for stricture

Radiographic Finding	Significance
String sign	Fibrostenotic stricture (terminal ileum)
Skip lesions	Discontinuous involvement (Crohn hallmark)
Cobblestoning	Transmural inflammation, deep ulcers
Fistula	Penetrating disease (Montreal B3)
Aphthous ulcers	Early mucosal lesions

🩻 TOACS FCPS Station · Barium Studies in Crohn Disease

📷 Barium Study (Small Bowel Follow‑Through)

🧑‍⚕️ Examiner tasks · TOACS

📌 Topic summary ·