Pneumococci resistant strains

Tyrothricin > 9 is bacteriostatic in concentrations of 0-01 figlml. and less for gram-positive cocci such as pneumococci, streptococci and staphylococci. At concentrations greater than 1 g/ml. it is bactericidal and some species of organisms, e.g. pneumococcus and staphylococcus are lysed. Gramnegative bacteria are much less sensitive. Many penicillin-resistant strains of cocci are sensitive to tyrothricin Table 1.7). 

A combination of trimethoprim-sulfamethoxazole is effective treatment for a wide variety of infections including P jiroveci pneumonia, shigellosis, systemic salmonella infections, urinary tract infections, prostatitis, and some nontuberculous mycobacterial infections. It is active against most Staphylococcus aureus strains, both methicillin-susceptible and methicillin-resistant, and against respiratory tract pathogens such as the pneumococcus, Haemophilus sp, Moraxella catarrhalis, and Klebsiella pneumoniae (but not Mycoplasma pneumoniae). However, the increasing prevalence of strains of E coli (up to 30% or more) and pneumococci that are resistant to trimethoprim-sulfamethoxazole must be considered before using this combination for empirical therapy of upper urinary tract infections or pneumonia. 

Streptococccus pneumoniae Pneumococcus) 5%-15% Person-person spread documented penicillin resistant and MDR strains problematic subtyping and antibiograms helpful to document transmission... 

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