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Appendix D Role of Public Health Laboratories in the Control of Tuberculosis
Pages 205-233

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From page 205...
... Experiences from the last few years are sufficient to warn of the need to be prepared for a resurgence of tuberculosis. There are 800 to 900 laboratories in the United States that can be classed as public health laboratories supported by government (federal, state, or local)
From page 206...
... Laboratories at that time were limited to the use of the slow, but reliable, methods that had been developed over decades. Therefore, detection of acid-fast bacilli by a specific stain could be accomplished in a local laboratory or on the ward of a hospital within hours of specimen collection, but isolation of tubercle bacilli and identification based on unique characteristics required inoculation of many tubes of solid media and subcultures to measure biochemical reactions.
From page 207...
... If drug resistance is present, the state tuberculosis control program should be notified promptly. (viii)
From page 208...
... The notification procedures are very detailed in Title 17, California Code of Regulations, Section 2505, Notification by Laboratories for in-state laboratories and out-of-state laboratories are covered. Tuberculosis controllers, public health laboratory directors, and health officers throughout the state have been made aware of this problem, but reports may not be received from the out-of-state laboratory (Royce, 1999~.
From page 209...
... Biological safety cabinets must be inspected and certified in situ at least annually by approved technicians, and personnel in the laboratory must be trained in their proper use, including location, control of room air flow, placement of materials and equipment within the cabinet, and understanding of the mechanics of air flow. Safety in the tuberculosis laboratory is essential in order to prevent infection of personnel and spread of tubercle bacilli through inappropriate disposal of contaminated wastes.
From page 210...
... If the specimen is to be transported for a short distance within a building, the primary container should be placed in a water tight package and transported with care. Decontamination and Staining Because the specimen usually contains bacteria other than mycobacteria, it must be decontaminated prior to culture on the rich media that were formulated to promote the growth of mycobacteria in general and of drug resistant tubercle bacilli in particular.
From page 211...
... This is time that could be spent in better ways. Culture and Identification Current Procedures Until 1993, the routine procedure in many tuberculosis laboratories was to inoculate the concentrated specimen onto one or more slants of solid medium, such as Lowenstein-lensen medium, which is an egg-based formulation, or Middlebrook 7H10 or 7Hll medium, which are agarbased media, and then to incubate the medium for at least 21 days at 37° C in an atmosphere of 5 to 10 percent carbon dioxide in air.
From page 212...
... The number of positive specimens detected by the BACTEC 460 plus solid media was 128 (97%) , by MGIT 960 plus solid medium was 121 (92%)
From page 213...
... The authors concluded "that although both nucleic acid amplification methods are rapid and specific for the detection of M tuberculosis in clinical specimens, AMTDII is significantly more sensitive than LCx with both respiratory (p = .005)
From page 214...
... The true species can be discerned through subsequent isolation and identification steps that will identify the species. In addition to the identification tests based on biochemical reactions, nucleic acid probes, and mycolic acid patterns, some investigators have been developing serologic tests, but often with poor success.
From page 215...
... The authors believe that the failure to follow NCCLS recommendations that biological safety cabinets used for culture should not be used for nucleic acid amplification studies may be responsible for the high number of false positives. These two studies serve as warnings that should be remembered as there is greater emphasis placed on developing more rapid tests for detection of M
From page 216...
... David (1970) determined that tubercle bacilli spontaneously mutate to resistance to four major antituberculosis drugs.
From page 217...
... M tuberculosis strains grow more rapidly in a liquid medium, such as BACTEC, so that the bacilli can be identified in two weeks or less, and the liquid medium is ready to use as an inoculum for drug susceptibility tests in new vials of BACTEC medium.
From page 218...
... In this study the data demonstrate that the MGIT tube is an accurate nonradiometric alternative to the BACTEC 460TB system for rapid susceptibility testing of M tuberculosis.
From page 219...
... Methods for verification and reliability of the tests should be included in the laboratory's policy and procedures manual. Proficiency Testing The Clinical Laboratory Improvement Amendments (Title 42 CFR 493.825)
From page 220...
... referred AFB-positive isolates to another laboratory for identification and drug-susceptibility testing, while 699 (32%) performed primary culture with identification, and 314 (14%)
From page 221...
... Level III performs all procedures of Level I, identifies all mycobacteria, and performs susceptibility tests. The Association of State and Territorial Public Health Laboratory Directors (ASTPHLD, now known as the Association of Laboratory Directors or ALD)
From page 222...
... Clinical Laboratories Improvement Amendment of 1988 Tests for staining, isolation, identification, drug susceptibility testing, and special tests for epidemiologic studies of tuberculosis are all considered complex tests in the Clinical Laboratory Improvement Amendments (CLIA) , Code of Federal Regulations, Chapter IV.
From page 223...
... Need for Training CDC recently surveyed 43 state public health laboratories, 8 nonstate public health laboratories, 87 hospital laboratories, and 7 commercial laboratories to get a first line response on what is perceived to be the training programs that would best serve their needs (Bird, 1999~. Although the results are in the preliminary stages of analysis, some needs stand out.
From page 224...
... Nontuberculous Mycobacteria Reported to the Public Health Laboratory Information System by State Public Health Laboratories, United States, 19931996, which can be accessed on http://www/cdc.gov/ncidod/dastlr/ mycobacteriology.htm)
From page 225...
... In answer to a survey question submitted to laboratory directors in preparation for this report, only eight of 45 state public health laboratory directors, but two of three territorial laboratory directors, indicated that they charged for tuberculosis laboratory diagnosis.
From page 226...
... T Crawford, Nontuberculous Mycobacteria Reported to the Public Health Laboratory Information System by State Public Health Laboratories, United States, 1993-1996, which can be accessed on http: / /www/cdc.gov/ncidod/ dastlr/ mycobacteriology.htm)
From page 227...
... Hospital and clinical laboratories develop relationships with commercial laboratories that may charge less for processing specimens than their state public health laboratory. Although the commercial laboratory is able to study specimens and report results in an efficient way in most instances, they should abide by the regulations of the state where specimens originate to ensure that reporting requirements for reportable diseases are all met (Skeets, 1999~.
From page 228...
... Replies indicated that state and territorial laboratories have updated procedures to speed identification and drug susceptibility testing. As indicated by the responses, public health laboratories are using the modern procedures available to them, and reports are being made to state tuberculosis programs in a timely manner.
From page 229...
... 1997. Evaluation of the semiautomated Abbott LCx Mycobacterium tuberculosis assay for direct detection of Mycobacterium tuberculosis in respiratory specimens.
From page 230...
... 1996. Clinical efficacy of the amplified Mycobacterium tuberculosis direct test for the diagnosis of pulmonary tuberculosis.
From page 231...
... 1998. Comparative evaluation of the new GenProbe Mycobacterium tuberculosis Amplified Direct Test and the semiautomated Abbott LCx Mycobacterium tuberculosis Assay for direct detection of Mycobacterium tuberculosis Complex in respiratory and extrapulmonary specimens.
From page 232...
... 1999. Evaluation of three nucleic acid amplification methods for direct detection of Mycobacterium tuberculosis complex in respiratory specimens.
From page 233...
... 1996. Detection of pulmonary and extrapulmonary tuberculosis patients with the 38-kilodalton antigen from Mycobacterium tuberculosis in a rapid membrane-based assay.


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