Which organism is described as Gram-positive diplococci with Lancet-shaped morphology?

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Multiple Choice

Which organism is described as Gram-positive diplococci with Lancet-shaped morphology?

Lancet-shaped Gram-positive diplococci point to Streptococcus pneumoniae. The paired, elongated cocci are characteristic, and pneumococcus is famous for this distinctive shape. It’s typically alpha-hemolytic on blood agar and encapsulated, which relates to its virulence and to tests like optochin sensitivity and bile solubility used to identify it. This organism stands apart from Staphylococcus aureus, which forms Gram-positive cocci in grape-like clusters; Streptococcus pyogenes, which forms Gram-positive cocci in chains and is beta-hemolytic; and Neisseria meningitidis, which is Gram-negative diplococci. The lancet-shaped diplococci feature is a classic clue for pneumococcus.

Lancet-shaped Gram-positive diplococci point to Streptococcus pneumoniae. The paired, elongated cocci are characteristic, and pneumococcus is famous for this distinctive shape. It’s typically alpha-hemolytic on blood agar and encapsulated, which relates to its virulence and to tests like optochin sensitivity and bile solubility used to identify it. This organism stands apart from Staphylococcus aureus, which forms Gram-positive cocci in grape-like clusters; Streptococcus pyogenes, which forms Gram-positive cocci in chains and is beta-hemolytic; and Neisseria meningitidis, which is Gram-negative diplococci. The lancet-shaped diplococci feature is a classic clue for pneumococcus.

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