system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A person from village is complaining of development of pustules. Extract from pus has shown gram positive cocci, showing hemolysis, catalase -ye, identified as a group of streptococci. Following test is used:
assistant
The correct answer is  Ans. (a) Bacitracin sensitivity "Sensitivity to bacitracin is employed as a convenient method for differentiating Str. pyogenes from other hemolytic streptococci." Pustule - A vesicle filled with leukocyte. MC cause is virus. MC bacterial cause is Strep. pyogenes. Remember: * Str pyogenes is the etiologic agent in most of the streptococcal skin infection. Vancomycin is the drug of choice. Optochin sensitivity and bile solubility is used to differentiate pneumococci from Strep. viridans group.