© 2002 American Thoracic Society
"TREATMENT OF LTBI": SELLING POINT OR SEMANTIC BLUNDER?To the Editor :The accepted meaning of "tuberculosis" (TB) is disease caused by Mycobacterium tuberculosis (although a cogent argument exists for a broader definition [1]). This usage implies that the disease is active and clinically identifiable, distinguishing TB from latent infection. Although one might debate the interface between latent (subclinical) infection and disease on a conceptual or pathological level, the distinction is crucial in the clinical and epidemiological spheres. In an unfortunate conflation of terms, the recently coined "latent tuberculosis infection" (LTBI [2]) blurs this distinction, confounding the longstanding efforts of clinical teachers to keep the concepts of infection and disease clear and their pharmacotherapy appropriate. "LTBI" joins a list of unsatisfactory phrases in clinical mycobacteriology that are flawed in both meaning and grammar (1, 3, 4), perhaps reflecting its design by a committee (even if expert). The now recommended "treatment of LTBI" (2, 5) sidesteps the ambiguity of "prevention" with regard to this mycobacterial infection (primary prevention of infection versus secondary prevention of active disease), and its familiar words (treatment, infection, TB) would have more impact than "chemoprophylaxis" in public advocacy for TB control, but I question whether the phrase is "more precise" (5) than its predecessors. The semantic problem could be solved at the expense of adding a six-syllable technical term: "latent Mycobacterium tuberculosis infection." Alternatively, "treatment of preclinical tuberculosis" would emphasize the importance of eradicating latent infection (with a pardonable stretch of meaning and, for most patients, prognosis). I am not convinced, however, that there was anything wrong with simply "preventing tuberculosis" in infected persons with appropriate drug(s).
SUNY Downstate Medical Center Brooklyn, New York REFERENCES
From the Authors: We read with interest the letter from Dr. Hill on nomenclature related to treatment of latent tuberculosis infection (LTBI), previously known as preventive therapy. He is not the first person to raise issues about this change in nomenclature; another colleague has recently expressed his concerns on a pathophysiologic basis (1). Dr. Hill contends that the recently-coined "LTBI" confuses efforts to distinguish concepts of tuberculosis infection and disease, as well as their requisite treatments. He does acknowledge that "treatment of LTBI" is less ambiguous than "prevention" in distinguishing the difference between primary prevention (i.e., preventing infection in the uninfected) and secondary prevention (i.e., treating infection to prevent disease). He suggests that the terminology "treatment of latent Mycobacterium tuberculosis infection" or "treatment of preclinical tuberculosis" might have been better alternatives. We agree with Dr. Hill that no terminology related to this subject will be absolutely precise on either clinical or pathologic grounds. And he is correct that the new nomenclature was indeed drafted by a committee of experts after much discussion (2). However, of note, despite several controversies in the development and subsequent publication of the ATS/CDC Statement "Targeted Tuberculin Testing and Treatment of Latent Tuberculosis Infection", there was little controversy and a great deal of consensus on the need for change in nomenclature (3). The terminology "treatment of latent Mycobacterium tuberculosis infection" was in fact considered, but was rejected as too cumbersome. We do not agree that "treatment of preclinical tuberculosis" would be more accurate, because a high percentage of persons with LTBI never develop clinical tuberculosis, even without intervention. We do want to reiterate that one of the main reasons for the change in nomenclature was to promote greater understanding of the concept for both patients and providers, which might then result in more widespread implementation of this important TB control strategy (2). In that regard, Dr. Hill is correct that the expert committee was trying to enhance public advocacy of TB control. In this day and age of enhanced patient involvement in decision making, the change in nomenclature was in part related to "marketing," perhaps at the expense (albeit small) of scientific precision.
Denver Public Health Denver, Colorado
Centers for Disease Control and Prevention Atlanta, Georgia REFERENCES
|
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
