Diplococci Neisseria gonorrhoeae. Streptococci Streptococcus pyogenes.
GENUS: NEISSERIA
description
Transcript of GENUS: NEISSERIA
GENUS: NEISSERIAAmany Niazy
Lab # 6
NEISSERIA SPECIESContains many species; 2 are
human pathogens◦Neisseria gonorrhoea (gonococcus)◦Neisseria meningitidis
(meningococcus)
Other species are normal flora that inhabit the upper respiratory tract of humans.
SPECIMENNeisseria gonorrhoea Urethral
discharge Genital swabs
(servical or rectal)
Neisseria meningitidis CSF
Fastidious organism very sensitive to environmental factors
Process specimen as
soon as possible
GRAM STAINDirect Gram Stain:
•Neisseria are intracellular organisms
•GNDC inside and outside pus cells (PMN) (kidney or bean shaped)
CULTUREInoculate into
◦ Chocolate Agar •Basal media at 40C (no solidification) add sheep blood•Keep in water bath at 70C to hemolyse blood•This releases and denatures many RBCs and serum proteins, making them more readily digestible to the bacteria•Colonies appear: Colorless , raised, 1-2 mm in diameter
CULTUREThayer Martin (selective medium)•Contain antibiotics to inhibit other bacteria and fungi
VCNT Vancomycin, Colistin, Nystatin, Trimethoprim.
INCUBATIONTemp 35-37 ˚C ONLY
Need 5-10% CO2 to grow: CO2 envelop in anaerobic jar or Candle jar
For 48 hours
Non-pathogenic Neisseria grow at room temperature
IDENTIFICATIONGram stain GNDC
Oxidase +ve
Carbohydrate utilization test
IDENTIFICATION 1. Gram stain from plate GNDC
(Kidney shaped)
IDENTIFICATION2. All Neisseria species are
Oxidase +vePreparation of Oxidase Test: •Add filter paper on a clean slide•Add 2-3 drops of oxidase reagent on filter paper•Use cover slip to transfer colony onto filter paper•+ ve Purple color
IDENTIFICATION3. HISS medium.broth + serum + sugar + indicator
(phenol red)
Neisseria gonorrhoeae
Neisseria meningitides
YOUR WORK FOR TODAY1. Prepare gram stain from culture.2. Do oxidase test.3. Subculture organism to chocolate
agar.4. Incubate in the CO2 jar.5. Read after 48 hours.6. See sugar utilization tube
(demonstration) 7. See intracellular GNDC slide
(demonstration slide)
• New diagnosis techniques:• Immunoassays• DNA hybridization• PCR
• Doc Kaiser’s microbiology website
http://student.ccbcmd.edu/~gkaiser/goshp.htm
Numbers in Saudi Population
13 cases of meningococcal meningitis in 2007
THANK YOU