Diagnostic Laboratory Tests of Bordetella pertussis
المؤلف:
Stefan Riedel, Jeffery A. Hobden, Steve Miller, Stephen A. Morse, Timothy A. Mietzner, Barbara Detrick, Thomas G. Mitchell, Judy A. Sakanari, Peter Hotez, Rojelio Mejia
المصدر:
Jawetz, Melnick, & Adelberg’s Medical Microbiology
الجزء والصفحة:
28e , p279-280
2025-09-13
287
A. Specimens
Nasopharyngeal (NP) swabs or NP aspirates using saline are the preferred specimens. Swabs should be either Dacron or rayon tipped and not calcium alginate, as it inhibits the polymerase chain reaction (PCR), nor cotton, as cotton kills the organisms. For adults, cough droplets expelled directly onto a “cough plate” held in front of the patient’s mouth during a paroxysm is a less desirable method of specimen collection.
B. Direct Fluorescent Antibody Test
The fluorescent antibody (FA) reagent can be used to examine nasopharyngeal swab specimens. However, false-positive and false-negative results may occur; the sensitivity is about 50%. The FA test is most useful in identifying B. pertussis after culture on solid media.
C. Culture
NP aspirates or swabs are cultured on solid media. The antibiotics in the media tend to inhibit other respiratory microbiota but permit growth of B. pertussis. Organisms are identified by immunofluorescence staining or by slide agglutination with specific antiserum.
D. Polymerase Chain Reaction
PCR and other nucleic acid amplification methods are the most sensitive methods to diagnose pertussis. Primers for both B. pertussis and B. parapertussis should be included. Where available, a nucleic acid amplification test should replace the direct FA tests. Existing primer targets may cross react with other Bordetella species.
E. Serology
Production of IgA, IgG, and IgM antibodies occurs after exposure to B. pertussis, and these antibodies can be detected by enzyme immunoassays. Serologic tests on patients are of little diagnostic help acutely because a rise in agglutinating or precipitating antibodies does not occur until the third week of illness. Serology may be useful in evaluating patients presenting between 2 and 4 weeks of illness. A single serum with high-titer anti-PT IgG may be helpful in diagnosing the cause of a long-term cough, that is, one of greater than 4 weeks’ duration.
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