Workbook in Microbiology 7e

Figure 27.2 Recommended procedures for laboratory diagnosis of gonorrhea by smear and culture. Source: Centers for Disease Control and Prevention, U.S. Public Health Service, Atlanta, Georgia, modified.

Figure 27.2 Recommended procedures for laboratory diagnosis of gonorrhea by smear and culture. Source: Centers for Disease Control and Prevention, U.S. Public Health Service, Atlanta, Georgia, modified.

Neisseria Jembec Culture System

organism in cultures of spinal fluid, blood, or the nasopharynx and identifying it by the criteria indicated in table 27.1-1. A latex agglutination test is available for detecting meningococcal antigen in cerebrospinal fluid. This test is not preferred over a Gram-stained smear of the fluid unless the patient has received antimicrobial therapy before the spinal tap is done.

In practical situations, it is important to remember that pathogenic Neisseria (gonococci and meningococci) are very sensitive to environmental conditions outside the human body, especially temperature and atmosphere. They are easily destroyed in specimens that are (1) delayed in transit to the laboratory, (2) kept at temperatures too far below or above 35°C, (3) heavily contaminated by normal flora, or (4) not promptly provided with an increased CO2 atmosphere (as in a candle jar). All specimens to be cultured for pathogenic Neisseria should be brought promptly and directly to the microbiologist. In situations when delays in specimen transport cannot be prevented, the JEMBEC system is recommended for use (see colorplate 38). This system consists of a rectangular culture plate containing modified Thayer-Martin or NYC agar medium. After the clinical sample has been inoculated onto the medium surface, a CO2-generating tablet is placed in a well located on the plate, and the plate is placed in a zip-lock plastic bag. Moisture in the culture medium activates the tablet, producing a CO2 atmosphere in the bag. On arrival in the laboratory, the JEMBEC culture plate is placed in a CO2 incubator at 35°C and observed for growth as usual. As before, laboratory identification of suspected N. gonorrhoeae is made according to the criteria in table 27.1-1. Use of this system improves recovery of N. gonorrhoeae from clinical samples that are delayed in transport. For nonculture tests, transport is less critical because nucleic acid (probe or gene amplification test) is more stable than are live organisms.

In the following experiment, you will have an opportunity to see the cultural and microscopic properties of some Neisseria species.

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Bacterial Vaginosis Facts

Bacterial Vaginosis Facts

This fact sheet is designed to provide you with information on Bacterial Vaginosis. Bacterial vaginosis is an abnormal vaginal condition that is characterized by vaginal discharge and results from an overgrowth of atypical bacteria in the vagina.

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