Chest Radiographic Findings in Primary Pulmonary Tuberculosis: Observations from High School Outbreaks

OBJECTIVE: To describe the radiographic findings of primary pulmonary tuberculosis (TB) in previously healthy adolescent patients. MATERIALS AND METHODS: The Institutional Review Board approved this retrospective study, with a waiver of informed consent from the patients. TB outbreaks occurred in 15 senior high schools and chest radiographs from 58 students with identical strains of TB were analyzed by restriction fragment length polymorphism analysis by two independent observers. Lesions of nodule(s), consolidation, or cavitation in the upper lung zones were classified as typical TB. Mediastinal lymph node enlargement; lesions of nodule(s), consolidation, or cavitation in lower lung zones; or pleural effusion were classified as atypical TB. Inter-observer agreement for the presence of each radiographic finding was examined by kappa statistics. RESULTS: Of 58 patients, three (5%) had normal chest radiographs. Cavitary lesions were present in 25 (45%) of 55 students. Lesions with upper lung zone predominance were observed in 27 (49%) patients, whereas lower lung zone predominance was noted in 18 (33%) patients. The remaining 10 (18%) patients had lesions in both upper and lower lung zones. Pleural effusion was not observed in any patient, nor was the mediastinal lymph node enlargement. Hilar lymph node enlargement was seen in only one (2%) patient. Overall, 37 (67%) students had the typical form of TB, whereas 18 (33%) had TB lesions of the atypical form. CONCLUSION: The most common radiographic findings in primary pulmonary TB by recent infection in previously healthy adolescents are upper lung lesions, which were thought to be radiographic findings of reactivation pulmonary TB by remote infection.

A Public-Private Collaboration Model for Treatment Intervention to Improve Outcomes in Patients with Tuberculosis in the Private Sector / 결핵및호흡기질환

BACKGROUND: The treatment success rates in patients with tuberculosis are known to be lower in the private sector compared to the public sector. To improve treatment outcomes in the private sector we developed a public-private collaboration model for strengthening health education and case holding activities with public health nursing in the private sector. METHODS: We performed a prospective cohort study in new smear positive pulmonary tuberculosis patients treated at private hospitals, selected by non-randomization, with an intervention consisting of health education and case holding activities by specially trained public health nurses (intervention group) results were compared with cases treated without the intervention (conventional group). Physicians were asked to treat both groups routinely. The treatment outcomes of patients under treatment by the National Tuberculosis Programme were also analyzed for comparison. RESULTS: There were 172 cases each in the intervention and conventional groups. The mean age was 48.9+/-19.0 and 48.2+/-19.7 in the respective groups (p=0.66). The PHN interacted with the cases in the intervention group by initial face to face interview and telephone calls an average of 7.1+/-9.2 times during the initial six months. The intervention group showed a significantly higher treatment success rate, 91.6%, (Rate Ratio [RR]; 1.23, 95% Confidence Interval [CI]; 1.12~1.36), lower default, 3.6%, (RR; 0.31, 95% CI; 0.13~0.75) and transfer-out rate, 3.0%, (RR; 0.32, 95% CI; 0.12~0.86) than the conventional group where they were: 75.0%, 11.6%, 9.3%, respectively. The success rate was even higher than the rate (80.5%) of 1,027 cases treated in health centers (RR; 1.11, 95% CI; 1.05~1.17). Of the completed cases in the intervention group, 82.2% regarded the role of the public health nurse as very helpful. CONCLUSION: The treatment success rate, of tuberculosis patients in the private sector, was significantly improved by an intervention using a public-private collaboration model.

In Vitro Antimicrobial Susceptibility of Mycobacterium abscessus in Korea

Mycobacterium abscessus is the second most common etiology of pulmonary disease caused by nontuberculous mycobacteria in Korea. Although antimicrobial susceptibility tests are important for appropriate patient management in M. abscessus lung disease, the tests have never been investigated in Korea. Seventy-four isolates of M. abscessus recovered from patient respiratory samples were tested against eight antimicrobial agents following the guidelines set forth by the National Committee for Clinical Laboratory Standards. Of the parenteral antibiotics, amikacin (99%, 73/74) and cefoxitin (99%, 73/74) were active against most isolates. Imipenem (55%, 36/66) and tobramycin (36%, 27/74) had activity against moderate number of isolates. Of the oral antibiotics, clarithromycin (91%, 67/74) was active against the majority of isolates. Moxifloxacin (73%, 54/74) and ciprofloxacin (57%, 42/74) had activity against a moderate number of isolates. Doxycycline was the least active, inhibiting only 7% (5/74) of isolates. In conclusion, the variations in susceptibility within M. abscessus isolates to currently available antimicrobials suggest that the antimicrobial susceptibilities of any clinically significant M. abscessus isolate be needed individually.

Drug Resistance Rate of New Pulmonary Tuberculosis Patients Treated from the Private Sector in 2003~2005 / 결핵및호흡기질환

BACKGROUND: Surveillance of TB drug resistance (DR) is essential for providing information on the magnitude and trends in resistance, for developing treatment guidelines and for monitoring the effect of interventions. Up to now national surveys of drug resistance of M. tuberculosis have been conducted four times since 1994 among patients registered at health centers. The purpose of this study is to estimate the prevalence of primary drug resistance among new cases identified in private sector, and to compare it with the previous national drug resistance surveys. METHODS: The study collected results of drug susceptibility testing (DST) performed at the Korean Institute of Tuberculosis by the request of private sector from January 2003 to December 2005, and then finally selected new cases for the analysis from the database of Korean TB Surveillance (KTBS) by matching patients' name and social identification numbers. RESULTS: Of the 5,132 new patients included in the study, 689 (13.4%) patients were found to have drug resistance at least one drug, 530 patients (10.3%) were isoniazid resistant, 195 patients (3.8%) were multi-drug resistant (MDR), and 21 patients (0.4%) were extensively drug resistant (XDR). The rate of drug resistance tended to decrease annually but it was not statistically significant. When compared with previous national DR surveys in 2003 and in 2004 respectively, they were not significantly different. CONCLUSION: The prevalence of DR among new cases managed in the private sector did not show significant difference from that of new patients registered in the public sector in the same year.

Treatment of Latent Tuberculosis Infection in Korea / 결핵및호흡기질환

No abstract available.

Tuberculin Survey to Estimate the Prevalence of Tuberculosis Infection of the Elementary Schoolchildren under High BCG Vaccination Coverage / 결핵및호흡기질환

BACKGROUND: Although the prevalence of tuberculosis infections (PTBI) is one of the basic epidemiologic indices, no survey has been carried out since 1995 because the nation-wide tuberculosis prevalence survey was changed to a surveillance system. Subjects without a BCG scar are examined in a tuberculin survey. However, it is very difficult to select these subjects under high vaccination coverage. It is important to evaluate the impact of BCG vaccinations on the tuberculin response and estimate the PTBI regardless of the BCG vaccination status. METHODS: A nation-wide, school-based cross-sectional tuberculin survey was carried out among first graders in elementary school in 2006. A total of 5,148 children in 40 schools were selected by quota sampling. Tuberculin testing with 0.1 ml of two tuberculin units of PPD RT23 was carried out on 4,018 children. The maximum transverse diameter of induration was measured 48 to 72 hours later. The presence of a BCG scar was checked separately. RESULTS: There were no BCG scars in 6.3% of the subjects. The mean induration size of tuberculin testing was 3.7+/-4.4 mm, which included 1,882 (46.8%) subjects with an induration size of 0 mm. The PTBI was 10.9% (439 subjects) using a cut-off point of > or =10 mm (conventional method). The annual risk of tuberculosis infections (ARTI) was 1.9% when the mean age of the subjects was assumed to be 6 years. There was no difference in the PTBI according to the presence or absence of a BCG scar [11.2% vs 7.6% (OR: 1.54, 95% CI: 0.98m2.43)]. Using a mirror image technique with 16 mm as the cut-off point, the PTBI and ARTI had decreased to 2.4% and 0.4% respectively. CONCLUSION: PTBI and ARTI, as estimated by conventional methods, appear to be high among BCG vaccinated children. A mirror image technique is more suitable for estimating the indices in a country with an intermediate burden of tuberculosis than the conventional method.

Detection of Clarithromycin-resistant Strains from Clinical Isolates of Mycobacterium abscessus / 결핵및호흡기질환

BACKGROUND: Mycobacterium abscessus is the most pathogenic and drug-resistant rapid-growing mycobacterium. Clarithromycin or azithromycin are the only regular oral antimycobacterial agents that have an effect on M. abscessus. We tried to detect the clarithromycin-resistant strains from the clinical isolates of M. abscessus. METHODS: We tried to isolate the clarithromycin-resistant strains from 220 clinical isolates of M. abscessus by performing using reverse hybridization assay (RHA) and the broth microdilution test (BMT). RESULTS: Seven resistant strains (3.2%) from all the tested clinical isolates were detected by BMT. Three of these resistant strains were also detected by RHA and it was confirmed that they had point mutants. CONCLUSION: These results showed that clarithromycin resistance in M. abscessus clinical isolates is related to a point mutation and other unknown mechanisms.

The Up-to-date of Anti-Tuberculosis Treatment / 결핵및호흡기질환

No abstract available.

Detection of embB Gene Mutation of Mycobacterium tuberculosis by Reverse Hybridization Assay / 결핵및호흡기질환

BACKGROUND: Ethambutol (EMB) is one of important first-line drug in the treatment of tuberculosis. Molecular techniques to detect embB gene mutations have been considered as an method to define the EMB resistance. We investigated the mutation rate within embB gene among EMB resistant strains using reverse hybridization techniques. METHODS: We made 11 probes that had wild or mutated sequences containing codons 306, 406, or 497 within embB gene respectively. These probes were reverse-hybridized with PCR products amplified from embB gene which were isolated from 149 ethambutol resistant strains and 50 pan-susceptible strains. RESULTS: Out of 149 ethambutol resistant strains, one hundred (67.1%) had mutation at least one base at codon 306, 406, or 497 in embB gene. Mutation at codon 306, 406, 497 were demonstrated in 75 (50.3%), 16 (10.7%), and 13 strains (8.7%) respectively. There were four strains that showed multi-mutation at codon 306 and codon 406 simultaneously. A high proportion (8.1%) had single mutation at codon 406. There was no mutation observed in embB gene among 50 pan-susceptible strains. CONCLUSION: Reverse hybridization will be useful technique for detection of gene mutation correlated to ethambutol resistance.

The Proportion of Rifabutin-susceptible Strains among Rifampicin- resistant Isolates and Its Specific rpoB Mutations / 결핵및호흡기질환

BACKGROUND: Rifabutin (ansamycin) is a spiro-piperidyl rifamycin, which is highly active against Mycobacterium tuberculosis. It has been found that some clinical isolates of tubercle bacilli that are resistant to rifampicin are susceptible to rifabutin, with some patients with multi-drug resistant pulmonary tuberculosis having shown favorable clinical and bacteriological responses to the rifabutin. This study was conducted to find the proportion of rifabutin- susceptible strains among rifampicin-resistant isolates from Korean MDR-TB patients, and investigate the presence of specific rpoB mutations, which may confer resistance to rifampicin, but not to rifabutin. METHODS: 201 rifampicin-resistant and 50 pan-susceptible M. tuberculosis isolates were randomly selected for this study. The isolates were retested at rifampicin and rifabutin concentrations of 0, 20, 40 and 80 microgram/ml, respectively. The isolates that grew at and/or over a rifabutin concentration of 20 microgram/ml were judged rifabutin-resistant. The rpoB gene was extracted from the isolates, and then amplified for direct sequencing to investigate specific rpoB mutations that conferred rifabutin- susceptibility but rifampicin-resistance. RESULTS: Out of the 201 rifampicin-resistant M. tuberculosis, 41 strains (20.4%) were susceptible to rifabutin using the absolute concentration method on Lowenstein-Jensen media. The rpoB mutation types that showed susceptibility to rifabutin were Leu511Pro, Ser512Arg, Gln513Glu, Asp516Ala, Asp516Gly, Asp516Val, Asp516Tyr, Ser522Leu, His526Asn, His526Leu, His526Cys, Arg529Pro and Leu533Pro. A reverse hybridization technique was able to detect 92.5% of the rifabutin-susceptible isolates, with a specificity of 96.1% among 195 M. tuberculosis isolates with the rpoB mutation. CONCLUSIONS: Around 20% of the rifampicin-resistant isolates in Korea showed susceptibility to rifabutin, which was associated with some specific mutations of rpoB. Rifabutin could be used for the treatment of MDR-TB patients, especially when drug susceptibility testing reveals susceptibility to rifabutin.

Implication of embB Gene Mutation in Ethambutol-Susceptible Clinical Isolates of Mycobacterium tuberculosis / 결핵및호흡기질환

BACKGROUND: Ethambutol(EMB) is one of the first-line drugs included in short-course anti-tuberculosis therapy. The point mutations in embB gene have been speculated to be associated EMB resistance. However, detection of embB mutations at these positions have been observed in both EMB-susceptible isolates; thus, it remains controversial whether these mutations are associated with EMB resistance METHODS: The 36 M. tuberculosis isolates were selected from clinical isolates which tested susceptible to EMB and resistant to at least one drug. DNA extracted from the isolates was analyzed by amplifying embB gene. The PCR products were purified and directly sequenced. We reviewed the history of past drug susceptibility test results. RESULTS: Out of 36 EMB-susceptible strains, 3 strains (8.3%) had a mutation in codon 306 or 406 of the embB gene. These three strains had at least isoniazid resistance. They grew at 1.0 mcg/ml of EMB in Lowenstein-Jensen media. The patients of the strains were continuously smear-positive for over 3 years despite taking TB therapy. One strain had been EMB-resistant in past drug susceptibility tests. CONCLUSION: EMB-susceptible strains containing embB mutation may be caused by decreased viability in vitro test not by itself.

Mycobacterium kansasii Pulmonary Diseases in Korea

Mycobacterium kansasii is one of the most common cause of pulmonary diseases due to nontuberculous mycobacteria. We investigated the changing in the number of isolation of M. kansasii and the clinical characteristics of M. kansasii pulmonary disease in Korea. Through searching the database of the Korean Institute of Tuberculosis, we identified the cases of isolated M. kansasii from 1992 to 2002. The number of M. kansasii isolation had increased from once in 1992 to 62 in 2002. Fifteen patients with M. kansasii pulmonary disease were identified during the period January 1997 to December 2002. Twelve patients (80%) were male and fourteen (93%) were from highly industrialized areas. The most common symptom was a cough. Seven patients (47%) had a cavitary lesion and right upper lobe was most commonly involved. Patients responded well to isoniazid and rifampicin based regimens both bacteriologically and radiographically. In conclusion, M. kansasii isolation has increased, especially in highly industrialized areas, as well as other nontuberculous mycobacteria in Korea.

A Trend in Acquired Drug Resistances of Tuberculosis Patients Registered in Health Centers from 1981 to 2004 / 결핵및호흡기질환

BACKGROUND: The drug resistance rate in tuberculosis patients with history of chemotherapy is an important indicator of for evaluation of appropriateness of treatment regimens and compliance of patients. This study examined the long-term changes in the drug resistance rates among TB patients failed in treatment or reactivated. METHODS: The results of drug susceptibility testing data from patients registered in health centers from 1981 to 2004 were analyzed. RESULTS: The rate of resistance to isoniazid decreased from 90% to 20%, and the resistance to ethambutol decreased from 45% to 6%. The rate of resistance to rifampicin varied from 13% to 28% and the resistance to pyrazinamide was 5% to 10%. Multidrug resistance was about 2-3% lower than any rifampicin resistance rates. The second-line drug resistance was ranged from 1% to 3%. There was no difference between patients' genders. Patient numbers per 100,000 population increased with age. The regional distribution was even at 4-6 patients per 100,000 population, and drug resistance rates were significantly lower in big city areas than in small towns and rural areas. CONCLUSION: The rates of resistance of Mycobacterium tuberculosis isolated from TB patients with history of chemotherapy to isoniazid, rifampin, ethambutol, and isoniazid plus rifampin were significantly decreased during over two decades.

Diagnosis and Treatment of Latent Tuberculosis Infection in Korea / 결핵및호흡기질환

No abstract available.

Tuberculosis Surveillance System in Korea / 결핵

No abstract available.

Tuberculosis Situation in Korea / 결핵

No abstract available.

Expression of Transforming Growth Factor-alpha and Transforming Growth Factor-beta In Human Primary Lung Cancers / 결핵

BACKGROUND: Transforming growth factor- alpha(TGF-alpha) may play important roles in carcinogenesis, tumor growth, and angiogenesis. Transforming growth factor-beta(TGF-beta) are known to be involved in cell-cycle control and regeneration. TGF-alpha positively acts on growth control of many epithelial cells in contrast to the negative role of TGF-beta. METHOD: To evaluate the possible role of TGF-alpha and TGF-beta in human primary lung cancers, the expression of TGF-alpha and TGF-beta were immmunohistochemically investigated in tissue sections from forty seven cases with lung cancers and ten cases with non-cancerous lung tissues. Recombinant cloned monoclonal antibody of TGF-alpha and neutralizing antibody of TGF-beta were employed as primary antibodies after dewaxing the formalin-fixed, paraffinized tissue sections. RESULTS: TGF-alpha was expressed in the cytoplasms of tumor cells in thirty five cases of forty seven(74.5%) primary lung cancers, whereas the control expressed in two of ten brochial epithelial cells. The expression of TGF-alpha was disclosed in four cases of eleven(36.4%) small cell carcinomas and thirty one cases of thirty six(86.1%) non-small cell carcinomas of the lung. Expressions of TGF-beta was discernible in bronchial epithelium in eight of ten non-cancerous lung tissues. The expression of TGF-beta was noted in the cytoplasms of tumor cells in eight cases of forty seven(17.0%) primary lung cancers. The expression of TGF-beta disclosed in two cases of eleven(18.2%) small cell carcinomas and six cases of thirty six(16.7%) non- small cell carcinomas of the lung. CONCLUSION: These findings suggest that up-regulation of TGF-alpha and down-regulation of TGF-beta are involved during development and growth of primary lung cancers.

The Fate of Intractable Tuberculosis Cases Under National Tuberculosis Programme / 결핵

BACKGROUND: The natural history of bacillary tuberculosis was studied in India and results showed that at the end of the 5-year period, 49% of the patients were dead, 33% were cured and 18% remained sputum-positive. The aim of this survey is to observe the natural course of the patients with intractable tuberculosis disease who were incurable with all drug regimens of the national tuberculosis programme(NTP). METHOD: Of the patients who have been found as intractable cases in Kang-Weon Province by the supervisory medical officer during the period from January 1,1987 to December 31,1992, 179 were eligible for this study. Sputum examination was done for those who were survived until October in 1993 at the Kang-Weon provincial laboratory of KNTA. 49 out of 179 patients were transferred to the private sectors and retreated with the combination of prothionamide, cycloserine, ofloxacin, enviomycin, etc. They seemed to have been bacteriologically cured, and so they were excluded from the study. Finally 130 patients were analyzed by modified life table method to calculate the fatality rate and the survival rate during the period of 7 years. RESULTS: 1) 80.8% of intractable cases were male and 19.2%,female. 2) More than 94% of intractable cases showed moderately or far advanced Tb findings on their X-rays at the time of registration at health centres. 3) The cumulative case-fatality rate was 19.74% at the end of 1-year period and has risen to 34.55% by the end of 4-year period(increasing by 4.9% a year on an average). The case-fatality rate has shown no appreciable rise since then until the end of 7-year period. 4) The case-survival rate was 80.26% at the end of 1-year period and has decreased to 65.45% by the end of 4-year period. And then there was no appreciable change in the survival rate until the end of 7-year observation. CONCLUSION: The case-survival rate of intractable cases was higher than that of untreated pulmonary tuberculosis patients and they may have risk of spreading multidrug resistant organisms. It is time we made an effort to improve case-management qualitatively.

Clinical experience on mycobacterial diseases other than tuberculos- is / 결핵

No abstract available.

Clinical analysis of 306 cases of cervical lymphadenopathy / 결핵

No abstract available.