Is Streptococcus pneumoniae optochin sensitive?
S. pneumoniae strains are sensitive to the chemical optochin (ethylhydrocupreine hydrochloride). Optochin sensitivity allows for the presumptive identification of alpha-hemolytic streptococci as S. pneumoniae, although some pneumococcal strains are optochin-resistant.
Which organism is identified by a positive optochin test?
Optochin is a chemical, ethylhydrocupreine hydrochloride and is completely soluble in water. It is useful in the identification of Streptococcus pneumoniae, the alpha-hemolytic Streptococcus most commonly susceptible to this chemical.
What is S. pneumoniae Gram-positive?
Streptococcus pneumoniae (pneumococcus) is a Gram-positive bacterium that is responsible for the majority of community-acquired pneumonia. It is a commensal organism in the human respiratory tract, meaning that it benefits from the human body, without harming it.
What is optochin target?
Optochin (Opt) susceptibility is used largely for the identification of Streptococcus pneumoniae in diagnostic laboratories. Opt-resistant (Optr) S. pneumoniae isolates have been reported, however, indicating the potential for misidentification of this important pathogen.
What does optochin resistant mean?
Optochin Resistant: No zone of inhibition around the disk. If the zone of inhibition is less than 14 mm, further testing (bile solubility or serology) should be done for the identification of other strains of Streptococcus pneumoniae.
Is pneumonia Gram-positive or negative?
Gram-positive pneumonia is a leading cause of morbidity and mortality throughout the world. Of the gram-positive pathogens that cause pneumonia, Streptococcus pneumoniae and Staphylococcus aureus are the most common.
What is optochin used for?
Optochin (ethylhydrocupreine hydrochloride) is currently widely used as an inexpensive and reliable means to presumptively identify Streptococcus pneumoniae. It has been known, since the turn of the century, when it was first synthesized, to inhibit the growth of S. pneumoniae.
