Moderate

A child presents with infective skin lesions of the leg. Culture was done which showed gram positive cocci in chains and haemolytic colonies. Which of the following tests will best identify the organism ?

Correct answer: C. Bacitracin sensitivity

  • A. Bile solubility
  • B. Optochin sensitivity
  • C. Bacitracin sensitivity
  • D. Cataslase positive

Explanation

Chains of Gram-positive cocci with haemolysis suggest a Streptococcus, and bacitracin sensitivity supports identification of Streptococcus pyogenes. Optochin is used for pneumococci, while catalase is negative in streptococci and cannot be positive here.

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