Isoniazid-Resistant Tuberculosis, Taiwan, 2000–2010

Corynebacterium ulcerans in an immuno-compromised patient with diphtheria and her dog. zoonotic transmission of toxigenic Cory-nebacterium ulcerans from companion animals in a human case of fatal diphtheria .acterization of toxigenic Corynebacterium ulcerans strains isolated from humans and domestic cats in the United Kingdom. Matrix-assisted laser desorption/ionisa-tion time-of-fl ight (MALDI-TOF) mass spectrometry as a tool for rapid diagnosis of potentially toxigenic Corynebacterium species in the laboratory management of diphtheria-associated bacteria. Euro Sur-tion of toxigenic Corynebacterium diph-theriae and Corynebacterium ulcerans strains by a novel real-time PCR. Methods for antimicrobial dilution and disk susceptibility testing of infrequently isolated or fastidious bacteria; approved guideline. 2nd ed. Wayne (PA): The Institute ; 2006. p. M45–A2. sequence typing identifi es evidence for re-combination and two distinct lineages of Corynebacterium diphtheriae. To the Editor: Vinnard et al. (1) reported that the risk factors associated with initial isoniazid resistance among patients with tuberculous meningitis in the United States during 1993– 2005 included young age (25–34 years) and foreign birth (1). In a previous survey, conducted in Taiwan during 2000–2008, we found the rate of antituberculosis drug resistance to be lower for older patients than for younger patients (2); however, current information about the patient characteristics associated with isoniazid-resistant tuberculosis (TB) in Taiwan is lacking. Therefore, to determine the risk factors associated with initial isoniazid resistance among patients with TB in Taiwan, we conducted a retrospective study.bed tertiary care center in northern Taiwan. We analyzed culture-confi rmed Mycobacterium tuberculosis isolates obtained from hospitalized patients during January 2000– December 2010. A nonduplicate isolate was defi ned as 1 isolate collected for evaluation from 1 patient who visited the hospital (as inpatient or outpatient). If multiple isolates were available from a patient, only the one fi rst isolated was analyzed. All specimens were processed and pretreated as described elsewhere (3). Patients with multidrug-resistant TB were excluded on the basis of evidence for differences in the epidemiology of isoniazid-resistant (rifampin-susceptible) TB and multidrug-resistant TB (4). Immigrant populations in Taiwan are limited; therefore, we did not analyze the origin of the patients. After excluding patients with multidrug-resistant TB, we analyzed 4,289 nonduplicate isolates, of which 3,842 (89.6%) were susceptible to isoniazid and the other 447 (10.4%) were resistant to isoniazid. In terms of demographic associations, patients 34–<44 years of age were more likely than those >74 years of age to have an isoniazid-resistant strain (Table). In addition, patients with extrapulmonary TB were less …