Page 207

able (Huebner et al., 1993, Woods and Witebsky, 1993). Since the laboratory was limited by the slow growth of the tubercle bacillus in culture, the predominant attitudes were that there was no need to rush reporting; however, with the newer techniques, reports of identification and drug susceptibility could affect patient treatment and recovery rather than being an addendum that might be of epidemiologic significance only.

THE CHALLENGE

Understanding that a radical change needed to be made if laboratory results were to contribute to the early diagnosis and treatment of patients with tuberculosis, Tenover et al. (1993) acknowledged improved technologies available at that time and recommended that tuberculosis laboratories take positive steps to improve performance, particularly in the time taken for testing and reporting results. These recommendations are still applicable as we start the year 2000, with modification only in the addition of newer probes which can be used to probe a specimen directly. The recommendations are as follows:

(i) Promote the rapid delivery of specimens to the laboratory on a daily basis, even if this requires pickup of individual specimens to guarantee arrival within 24 h.

(ii) Use a fluorescent acid-fast staining procedure and use the time saved to immediately transmit the results by telephone or facsimile device for inclusion in patients' records.

(iii) Report patients who are suspected of having tuberculosis on clinical grounds or patients with acid-fast bacilli present on smears to the local health department promptly so that appropriate public health management (including contact investigation) can be initiated.

(iv) Inoculate a liquid medium as primary culture, and include inoculation of a slant of Lowenstein-Jensen medium.

(v) Identify growth in liquid medium as acid fast and use probes, NAP, or mycolic acid patterns to identify isolates as M. tuberculosis as soon as possible. Notify the local health department of the species identification as soon as it is known.

(vi) Determine the susceptibilities of M. tuberculosis isolates to primary drugs in a BACTEC or similar system.

(vii) Report the results of drug susceptibility testing to the clinician as soon as they are available by telephone or facsimile and follow up with hard copy. If drug resistance is present, the state tuberculosis control program should be notified promptly.

(viii) Maintain up-to-date records that include the results of quality control procedures.

(ix) Review all laboratory procedures and facilities to guarantee safety for workers.



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement