The speciation of coagulase negative Staphylococcus is necessary in certain culture specimens. Coagulase negative staphylococci can either be resistant or susceptible to novobiocin. The one most commonly isolated novobiocin resistant coagulase negative staphylococcus from urine is Staphylococcus saprophyticus. It is one of the most common causes of urinary tract infections in sexually active young women. So, […]
Roundworm passes its life cycle in single host and no intermediate host (the host that harbors larval stage of parasite) is required. Man is the only definitive host (the host in which parasite harbors its adult stage or it utilizes sexual method of reproduction) of A. lumbricoides. The various stages in life cycle are described […]
Principle: Albert stain is done to identify Corynebacterium diphtheriae. This stain differentially stains the metachromatic granules and cytoplasm of this bacterium. Procedure: Prepare a smear and fix it by gently heat over a flame. Cover the smear with Albert stain (Albert I) staining solution. Allow it for 5 minutes. Pour off the stain after 5 […]
Principle of Bile Solubility test: Bile solubility test is used to differentiate Streptococcus pneumoniae from other alpha-hemolytic Streptococci. Streptococcus pneumoniae is bile soluble whereas all other alpha-hemolytic streptococci are insoluble. Bile or a solution of bile salt, like sodium desoxycholate rapidly lyses the pneumococcal colonies. This lysis depends on the presence of intracellular autolytic enzyme. Bile […]
Principle: Optochin (ethyl hydrocupreine hydrochloride) sensitivity test is used for the presumptive identification of alpha-hemolytic streptococci as Streptococcus pneumoniae. Optochin is used to differentiate Streptococcus pneumoniae from other alpha-hemolytic streptococci. Streptococcus pneumoniae strains are sensitive to Optochin although some strains are optochin-resistant and other alpha-hemolytic streptococcal species are Optochin-resistant. The Optochin test is performed on […]