26.5.2013 10:09:19 .kili.
Re: Výhody a nevýhody hexy ve třech měsících nebo v půl roce?
"když jsem se kdysi "
to je vývoj. Dnmes je to s laboratorní diagnostikou B.p. asi takto :
Nelson, Textbook od Pediatrics, 19th edition, actulalisated 2013
Part XVII - Infectious Diseases
Section 5 - Gram-Negative Bacterial Infections
Chapter 189 - Pertussis (Bordetella pertussis and Bordetella parapertussis)
Diagnosis
All current methods for confirmation of infection due to B. pertussis have limitations in sensitivity, specificity, or practicality. Isolation of B. pertussis in culture remains the gold standard for diagnosis. Careful attention must be directed to specimen collection, transport, and isolation technique. The specimen is obtained with deep nasopharyngeal aspiration or with the use of a flexible swab, preferably a Dacron or calcium alginate–tipped swab, held in the posterior nasopharynx for 15-30 sec (or until cough occurs). A 1.0% casamino acid liquid is acceptable for holding a specimen up to 2 hr; Stainer-Scholte broth or Regan-Lowe semisolid transport medium is used for longer transport periods, up to 4 days. The preferred isolation media are Regan-Lowe charcoal agar with 10% horse blood and 5-40 µg/mL cephalexin and Stainer-Scholte media with cyclodextrin resins. Cultures are incubated at 35-37°F in a humid environment and examined daily for 7 days for slow-growing, tiny, glistening colonies. Direct fluorescent antibody (DFA) testing of potential isolates using specific antibody for B. pertussis and B. parapertussis maximizes recovery rates. Direct testing of nasopharyngeal secretions by DFA is a rapid test but is reliable only in laboratories with continuous experience. Polymerase chain reaction (PCR) analysis to test nasopharyngeal wash specimens has a sensitivity similar to that of culture and averts difficulties of isolation, but a standardized validated test is not yet available universally. Results of DFA, culture, and PCR are all expected to be positive in unimmunized, untreated children during the catarrhal and early paroxysmal stages of disease. Less than 10% of any of these test results are positive in partially or remotely immunized individuals tested in the paroxysmal stage. Serologic tests for detection of antibodies to B. pertussis antigens in acute and convalescent samples are the most sensitive tests in immunized individuals and are useful epidemiologically. A single serum sample showing immunoglobulin G (IgG) antibody to pertussis toxin elevated >2 standard deviations above the mean of the immunized population (≈100 EU/mL) indicates recent infection. Standardization of tests and cut point for a positive result are currently being investigated. Tests for IgA and IgM pertussis antibody, or antibody to antigens other than PT, are not reliable methods for diagnosis of pertussis.
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