In an asymptomatic adult with a 3.5 cm mildly dilated fluid‑filled jejunal segment that normalizes distally, a short fluid‑filled distal ileal segment, and subcentimeter lymph nodes, what is the most likely diagnosis and appropriate next steps?

Asymptomatic Fluid-Filled Jejunal and Ileal Segments with Subcentimeter Lymph Nodes

In an asymptomatic adult with these imaging findings—mild jejunal dilation (3.5 cm) that normalizes distally, fluid-filled distal ileum, and subcentimeter lymph nodes—this most likely represents a normal variant or physiologic finding that requires no immediate intervention.

Most Likely Diagnosis

• Normal physiologic fluid distribution is the primary consideration in an asymptomatic patient with these findings 1
• The smooth distal normalization of caliber without discrete abnormality argues strongly against pathologic obstruction 1
• Subcentimeter lymph nodes (<10 mm in short axis) are considered benign and require no follow-up in asymptomatic patients 2, 3

Key Discriminating Features Present in This Case

• Absence of upstream dilation >3 cm: The 3.5 cm jejunal segment is only mildly prominent and does not meet criteria for significant obstruction, which typically requires unequivocal upstream dilation to diagnose a stricture 1
• Smooth transition without discrete abnormality: This pattern lacks the imaging hallmarks of inflammatory bowel disease, which would show wall thickening (>3-5 mm), mural hyperenhancement, or ulcerations 1
• Asymptomatic presentation: The absence of symptoms makes significant pathology highly unlikely 1

What This is NOT

• Not Crohn's disease: Crohn's-related inflammation requires segmental hyperenhancement with wall thickening, and severe inflammation shows ulcerations or high T2 intramural signal 1
• Not a true stricture: A stricture requires both luminal narrowing AND unequivocal upstream dilation (typically >3 cm), which is not present here 1
• Not concerning lymphadenopathy: Lymph nodes <15 mm in short axis are considered benign if no concerning features are present, and subcentimeter nodes specifically require no workup 2, 4

Common Pitfalls to Avoid

• Do not over-interpret normal jejunal restricted diffusion: The normal jejunum demonstrates increased relative nonfocal restricted diffusion compared to the normal ileum, and diagnosis of active Crohn's disease should not be made on the basis of restricted diffusion alone 1
• Do not confuse mild fluid distention with obstruction: Low-grade or intermittent obstruction is difficult to diagnose and typically requires provocative measures like CT enterography or enteroclysis to visualize consistently 1
• Do not pursue lymph node biopsy for subcentimeter nodes: Reactive lymphadenopathy 1-1.5 cm in short axis is considered normal in many conditions, and nodes <15 mm without loss of fatty hilum or irregular borders require no further workup 2, 4

Appropriate Next Steps

• No immediate intervention required for an asymptomatic patient with these findings 2, 3
• Clinical correlation only: If the patient develops symptoms (abdominal pain, obstruction symptoms, B symptoms like fever/night sweats/weight loss), then advanced imaging with CT or MR enterography would be appropriate 1
• No follow-up imaging needed for the subcentimeter lymph nodes in an asymptomatic patient 2, 3

When to Escalate Care

• Development of obstructive symptoms (nausea, vomiting, inability to tolerate oral intake) 1
• Systemic symptoms suggesting inflammatory or malignant process (fever, night sweats, weight loss, chronic diarrhea) 2
• Progressive dilation on follow-up imaging performed for other reasons 1
• Lymph nodes that grow beyond 15 mm or develop loss of fatty hilum or irregular borders 2, 4