A 5-year-old child presents with pustular lesions on the lower legs. The culture from the lesion showed hemolytic colonies on blood agar which were Gram-positive cocci. Provisional diagnosis of Group A streptococcal pyoderma can be done by?
Ans. (a) Catalase positivity Pyoderma (Impetigo Superficial infection of the skin, caused primarily by Group A Streptococci and Staphylococci Usual site of infection are face (paicularly around nose and mouth) and the legs Diagnosis is based on the culture and staining of indeginous lesion. Gram positive cocci if catalase positive, than it is most likely to be Staphylococci and if catalase negative than it is Streptococci
Catalase positivity
Optochin sensitivity
Bile solubility
Bacitracin sensitivity