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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 boy with skin ulcer on the leg, culture reveals beta hemolysis. Cultures from school children with a sore throat some days back also revealed beta hemolysis. What is the similarity between both
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The correct answer is  CARBOHYDRATE ANTIGEN: On the basis of the C carbohydrate antigen, S.pyogenes is classified under Lancefield group A. This antigen shows cross-reactivity with some human tissues. This antigen is an integral pa of the cell wall, it has to be extracted for grouping by precipitin test with group antisera. Reference: Textbook of Microbiology; Anathanarayan and paniker's; 10th edition; Page no: 212