Hypersensitivity reactions after barium enema examination

Area of Science:

• Radiology
• Allergology
• Clinical Medicine

Background:

• Air-contrast barium enema is a common diagnostic imaging procedure for the colon.
• Adverse reactions to barium contrast media are rare.
• Urticaria is a common allergic skin reaction characterized by transient wheals and itching.

Observation:

• Three patients presented with urticaria developing shortly after undergoing air-contrast barium enema.
• A review of medical literature revealed only one previously reported similar case.
• One patient exhibited a positive prick skin test specifically to methylparaben.

Findings:

• Methylparaben, identified as a preservative in the barium mixture, is implicated as the causative allergen.
• The findings suggest methylparaben in barium contrast preparations can trigger allergic urticaria.
• This case report highlights a potential, albeit rare, adverse reaction to barium enema.

Implications:

• Clinicians should consider allergic reactions to barium additives, such as methylparaben, in patients developing urticaria post-procedure.
• Further investigation into the allergenicity of barium contrast media components may be warranted.
• Awareness of this potential adverse effect can aid in prompt diagnosis and management of post-procedural urticaria.