The morphology known as the 'seagull wings' on Gram stain is most characteristic of which organism?

• A. Campylobacter jejuni
• B. Neisseria gonorrhoeae
• C. Plesiomonas shigelloides
• D. Yersinia pseudotuberculosis

Answer: (A)

Seagull wings on a Gram stain describe curved, slender Gram-negative rods that often pair up in a way that their adjacent angles resemble the wings of a seagull. This appearance is classic for Campylobacter jejuni, which is a microaerophilic, motile curved rod commonly causing gastroenteritis after exposure to undercooked poultry or unpasteurized dairy.

Other organisms listed have different basic shapes on Gram stain: Neisseria gonorrhoeae appear as kidney-shaped diplococci; Plesiomonas shigelloides is a curved rod but not typically described with seagull-wing morphology; Yersinia pseudotuberculosis is a small gram-negative coccobacillus with a distinct staining appearance. Thus, the seagull-wing pattern most strongly points to Campylobacter jejuni.