Pulmonary Tuberculosis Incidence among Interferon-Gamma Release Assay-Positive Individuals with Latent Tuberculosis Infection and Fibrotic Lesions in a Vulnerable Urban Population in Osaka City, Japan, 2015-2021.

Latent tuberculosis infection (LTBI) with fibrotic lesions (FL) can progress to active tuberculosis (TB). Most previous studies have used tuberculin skin tests, which have lower specificity than interferon-gamma release assays (IGRAs), for LTBI diagnosis. This study evaluated the incidence of active TB among individuals with LTBI (diagnosed using IGRAs) and FL in Nishinari District, Osaka City. In total, 54 men (mean age: 68.7 years) were enrolled, of whom 10 (18.5%) were homeless, and 36 (66.7%) were welfare recipients. The median observation period was 1,084 days (range: 64-2,907 days). The incidence rate of active TB among individuals with LTBI and FL was 1.18 (95% confidence interval: 0.32-4.29) cases per 100 person-years. Among the 19 participants who had not been treated with anti-TB therapy, one (5.3%) progressed to active TB, and among the 30 participants who had completed anti-TB treatment, one (3.3%) progressed to active TB. The other 5 participants did not have TB. This study revealed the incidence of active TB among individuals with LTBI, diagnosed using IGRAs, and FL in a vulnerable urban population. The higher incidence than that reported in previous studies reinforces the importance of improved LTBI management strategies, including chest radiography screening, and LTBI treatment.

Active Case Finding Using Mobile Chest Radiography among Homeless People with Pulmonary Tuberculosis in Osaka City, Japan, 2013-2019.

Mobile digital chest radiography (CR) is a commonly used method for pulmonary tuberculosis (PTB) screening among homeless people in Nishinari District, Osaka City, Japan. We investigated mobile CR screening (MCS) to calculate the case-finding rate of culture-confirmed PTB among homeless examinees in Nishinari District from 2013 to 2019. PTB was defined as a sputum culture-confirmed case. Examinees with culture-confirmed PTB >90 days after MCS were defined as having no progression to active tuberculosis when undergoing MCS. We collected participants' information, including their name, date of birth, age, sex, date of MCS, CR classification (whether the abnormal CR result required further investigation), date of PTB diagnosis, and sputum smear results. Of 10,111 homeless people, 175 (1.7%) with abnormal CR results underwent further investigation at medical facilities. Of those with abnormal CR results, 22 (0.22%) were diagnosed with culture-positive PTB within 90 days of MCS. Of 22 PTB cases with culture-positive results, 13 (59.1%) were smear-positive. We found that MCS contributed to the detection of PTBs with a lower smear-positive rate among patients with PTB analyzed by MCS compared with all culture-confirmed PTB cases in Nishinari District.

Factors associated with mortality among patients with culture-positive pulmonary tuberculosis in the urban poor population of Osaka City, Japan.

OBJECTIVE: To determine the characteristics associated with mortality in patients with culture-positive pulmonary tuberculosis (PTB) in Airin, Osaka City, Japan. METHODS: The characteristics of patients with culture-positive PTB registered between 2015 and 2018 in Airin, Osaka City, Japan, were compared between those who died of all causes before or during treatment and those who completed treatment. RESULTS: Of the 241 culture-positive PTB patients eligible for this study, 170 completed treatment, with negative sputum culture tests, and 62 died. The all-cause case fatality rate was 26.7% (62/232). Multivariate analysis showed that mortality was associated with age 370 years, having a positive sputum smear, a body mass index of < 18.5 and serious comorbidities such as cancer and heart and renal disease. Detection of tuberculosis (TB) by screening or in an outpatient department (OPD) for other diseases was inversely associated with mortality. DISCUSSION: Detection of PTB by chest X-ray screening and during regular visits to OPDs for other diseases was associated with non-fatal TB and might contribute to early case finding. Therefore, current active TB case finding and health education on regular visits to physicians for other diseases should be strengthened further for the urban poor population of Osaka City, Japan.

[Treatment outcome of latent tuberculosis infection in persons with fibrotic pulmonary lesions].

Objective　This study aimed to evaluate the treatment outcome of latent tuberculosis infection (LTBI) in persons with fibrotic pulmonary lesions, treated with isoniazid (INH) or rifampicin (RFP) in Nishinari Ward, Osaka City.Methods　As part of a tuberculosis screening program by chest X-ray (CXR), we selected persons who met the following four criteria for initiation of LTBI treatment:①Anti-tuberculosis treatment has not been performed for more than one month in the past. ②CXR shows fibrotic pulmonary lesions.③Fibrotic pulmonary lesions with CXR have not changed for more than one year.④QuantiFERON TB Gold-in-tube (QFT) shows positive values (≥0.35 IU/mL).　Before treatment, the blood samples were within the standard values for aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, and serum creatinine. Treatment with INH was stopped when AST or ALT levels were elevated to more than 150 IU/L, or symptoms of liver dysfunction appeared even when AST or ALT levels were less than 150 IU/L. After liver dysfunction improved, treatment with RFP was started.　Treatment completion was defined as being dispensed with INH for ≥180 days or RFP for ≥120 days.Results　The 27 participants were all male and their age was 68.4±6.6 years. Of the 27 participants, 14 (51.9%) completed treatment with INH. Of the remaining 13 persons, nine (69.2%) stopped treatment with INH because of liver dysfunction. Nine restarted RFP treatment and all participants completed the treatment without interruption by liver dysfunction. In total, 23 (85.2%) completed the treatment.Conclusion　LTBI treatment with INH in persons with fibrotic pulmonary lesions in the area where people in financial need live was stopped because of liver dysfunction; however, changes from INH to RFP could improve treatment outcomes.

Characteristics of individuals with tuberculosis in an urban, poor population in Osaka City, Japan - a case-control study.

OBJECTIVE: To identify individual characteristics related to the development of pulmonary tuberculosis (PTB) among residents in the Airin area (Airin), Osaka City, Japan. METHODS: We conducted a retrospective case-control study of individual characteristics potentially related to the development of PTB by comparing PTB patients and residents without tuberculosis (TB) in Airin. The following binominal data of characteristics were compared: age (< 65 or > 65); body mass index (BMI) (< 18.5 or > 18.5); diabetes mellitus (diagnosed or not diagnosed); smoking (currently smoking any amount or not smoking); and alcohol use (currently drinking any amount or not drinking). RESULTS: We compared the individual characteristics of 192 PTB patients notified from January 2015 to December 2018 and 190 residents of supportive houses who attended a health education programme from April 2016 to March 2018.Univariable analysis showed that the following characteristics were significantly related with PTB: BMI < 18.5 (odds ratio [OR]: 6.54, 95% confidence interval [CI]: 3.58-11.97, P < 0.001) and current alcohol use (OR: 1.88; 95% CI: 1.24-2.85, P = 0.003). Multivariable analysis showed similar results: BMI < 18.5 (adjusted odds ratio [aOR]: 6.90, 95% CI: 3.72-12.79, P < 0.001) and current alcohol use (aOR: 2.15, 95% CI: 1.36-3.42, P = 0.001). DISCUSSION: Undernutrition and alcohol use are individual characteristics associated with PTB among residents in Airin, Osaka City. To strengthen the TB control programme further, it is suggested to develop new programmes for primary prevention.

Longitudinal genotyping surveillance of Mycobacterium tuberculosis in an area with high tuberculosis incidence shows high transmission rate of the modern Beijing subfamily in Japan.

Tuberculosis (TB) is a severe and wide-spread infectious disease worldwide. The modern Beijing subfamily, one lineage of M. tuberculosis, reportedly has high pathogenicity and transmissibility. This study used a molecular epidemiological approach to investigate the transmissibility of the modern Beijing subfamily in the Airin area of Osaka City, Japan. During 2006-2016, we collected 596 M. tuberculosis clinical isolates in the Airin area, Osaka city, Japan. We analyzed the 24-locus variable number of tandem repeats typing optimized for the Beijing family of isolates, M. tuberculosis lineage, and patient epidemiological data. The proportion of the modern Beijing subfamily was significantly higher not only than previously obtained data for the Airin area: it was also higher than the nationwide in Japan. The rate of recent clusters, defined as a variable number of tandem repeats profile identified within two years, of the modern Beijing subfamily was significantly higher than that the rate of recent clusters of the ancient Beijing subfamily. Results suggest that TB control measures formulated with attention to the modern Beijing subfamily might be an important benchmark to understanding recent TB transmission in the area.

[TREATMENT SUPPORT AND TREATMENT QUTCOMES OF PULMONARY TUBERCULOSIS IN PATIENTS WITH HIV INFECTION IN OSAKA CITY].

[Objective] To contribute to countermeasures against pulmonary tuberculosis in patients with HIV infection through analyzing and evaluating its treatment outcomes and patient management. [Methods] The 'subjects were pulmonary tuberculosis patients newly registered between 2008 and 2014 in whom concomitant HIV infection was detected. For the control, sex- and generation-matched pulmonary tuberculosis patients newly registered in Osaka City -between 2012 and 2014 were adopted. On analysis, the X² test and Fisher's exact test were used, and a significance level below 5% was regarded as significant. [Results] 1) There were 25 pulmonary tuberculosis patients complicated by HIV. All were male -and the mean age was 43.2 years old. 2) The sputum smear positivity rate was 76.0% in the pulmonary tuberculosis patients complicated by HIV and 50.8 % in 250 control pulmonary tuberculosis patients, showing a significantly higher rate in the former. 3) Risk factors for the discontinuation of medication for tuberculosis: In the patients complicated by HIV, the follow- ing risks of the discontinuation of medication were noted in the order of a decreasing frequency: 'Lack of medication helpers' in 68.0%, 'Side effects' in 48.0%, 'Financial prob- lems' in 32.0%, and 'Liver damage' in 28.0%. Those in the control pulmonary tuberculosis patients were 33.2%, 22.8 %, 16.0%, and 11.6%, respectively, showing a significant difference in each factor. 4) The DOTS executing rates were 68.0% and 94.8% in the patients complicated by HIV and control patients, respectively, showing that it was significantly lower in the patients complicated by HIV. On comparison of the treatment outcomes excluding died, on treatment, transferred out, not evaluated, treatment succeeded in 72.7% in the patients complicated by HIV and 92.9% in the control patients, showing a significantly lower success rate in the patients complicated by HIV. The numbers of risk factors of discon- tinuation in. 16 and 6 patients complicated by HIV in whom treatment succeeded and treatment failed/defaulted were 3.8 and 2.8, respectively, showing that the number was higher in patients with successful treatment, and the DOTS execution rates were 75.0% and 33.3%, respectively, showing a higher rate in the successful treatment cases. [Conclusion] The treatment outcome was significantly poorer in pulmonary tuberculosis patients complicated by HIV than in the control pulmonary tuberculosis patients. More risk factors for the discontinuation of medication were observed and the DOTS execution rate was lower in the patients complicated by HIV, suggesting that risk assess- fient for the discontinuation of medication should be appro- priately performed, and support for medication should be strengthened.

[USE OF QuantiFERON® TB-GOLD IN-TUBE IN A CONTACT INVESTIGATION TO DETERMINE THE ONSET OF TUBERCULOSIS WITH OR WITHOUT LATENT TUBERCULOSIS INFECTION TREATMENT].

PURPOSE: QuantiFERON® TB-Gold In-Tube (3G) testing was performed on tuberculosis-positive index cases and their contacts. The purpose of this study was to evaluate the relationship between 3G test results and the subsequent development of tuberculosis, and to identify effective strategies to prevent the onset of tuberculosis. METHODS: Index cases and their contacts were subjected to 3G testing in a contact investigation in Osaka City in 2011-2012. For index cases, sputum smears were tested, and the infecting organism was identified. For the contacts, the following information was collected: age, results of 3G testing, presence or absence of latent tuberculosis infection (LTBI) treatment, and onset of tuberculosis disease within 2 years of follow-up from the last contact with the index cases. RESULTS: (1) There were 830 index cases, including 774 subjects with pulmonary tuberculosis (93.3%) and 3 with laryngeal tuberculosis (0.4%). From sputum smear tests, 726 patients (87.5%) were determined to be 3G positive, and 83 (10.0%) were determined to be 3G negative. (2) In total, 2,644 contacts were subjected to 3G testing. Of these, 2,072 patients (78.4%) tested negative, 196 (7.4%) showed an equivocal result, and 375 (14.2%) tested positive. Their mean ages were 33.7, 38.0, and 38.8 years, respectively, showing significant differences in tuberculosis status according to age (P < 0.001). (3) Among the 2,072 3G-negative contacts, tuberculosis developed in 2 (0.1%) of 2063. None of these contacts was treated for LTBI. Among the 375 3G-positive contacts, tuberculosis developed in 36 (36.0%) of 100 subjects that were not LTBI treated, while tuberculosis developed in 3 (1.1 %) of 275 subjects that were LTBI treated. A significant difference in the incidence of tuberculosis between treated and untreated 3G-positive contacts was observed (P < 0.001). DISCUSSION: Tuberculosis developed in a high proportion of 3G-positive contacts that were not LTBI treated, suggesting the need for preventive management of 3G-positive contacts.

[DOTS AND TREATMENT RESULTS IN PATIENTS WITH EXTRA-PULMONARY TUBERCULOSIS IN OSAKA CITY].

[Purpose] To improve the treatment outcomes by analyzing/evaluating the association between DOTS and treatment outcomes in patients with extra-pulmonary tuber- culosis. [Methods] The subjects were patients with extra-pulmonary tuberculosis newly registered in Osaka City between 2012 and 2014. As controls, patients with pulmonary tuberculosis during this period were enrolled. Patients in whom compli- ance was confirmed once a month or more were regarded as completing DOTS. [Results] There were 434 patients with extra-pulmonary tuberculosis. Treatment was completed in 73.3% of these patients. Defaulted rates accounted for 9.4%. The mortality rate was 13.4%. Treatment is being conducted in 2.8%. Furthermore, 0.7% was transferred out. The results were unclear in 0.5%. We investigated changes in the DOTS and defaulted rates, excluding patients who died, those who were referred to other hospitals, those receiving treatment, and those whose results were unclear. The DOTS rates in 2012, 2013, and 2014 were 85.5, 87.5, and 91.2%, respectively, showing a slight increase. The defaulted rates were 14.5, 10.7, and 7.8%, respectively, showing a decrease. When compar- ing the results between the extra-pulmonary and pulmonary tuberculosis patients, the defaulted rates were 11.4 and 6.2 %, respectively; the percentage was significantly higher in the extra-pulmonary tuberculosis patients. The DOTS rates were 87.7 and 97.2%, respectively; the percentage was sig- nificantly lower in the extra-pulmonary tuberculosis patients. There were 41 defaulted cases. The reasons were "side effects" in 41.5%, "physicians' instructions" in 24.4%, "self- discontinuation/refusal" in 22.0%, and "preferential treatment for other diseases" in 12.2%. In the extra-pulmonary tuberculosis patients, the proportion of those in whom "side effects" led to defaulted was higher than in the pulmonary tubercu- losis patients, and that of those "self-discontinuation/refusal" was significantly lower. [Conclusion] Although the defaulted rate has decreased with an increase in the DOTS rate in patients with extra- pulmonary tuberculosis, both the DOTS and defaulted rates were less favorable than in patients with pulmonary tuber- culosis. In the future, it may be necessary to decrease the defaulted rate by intensifying DOTS. Of the reasons for defaulted, "side effects" and "physicians' instructions" account- ed for a high percentage. Therefore, it may be important to provide medical institutions with information.

[EXAMINATION OF TUBERCULOSIS OUTBREAK INDEX CASES IN OSAKA CITY].

OBJECTIVE: To analyze tuberculosis outbreak index cases in order to improve preventative measures. METHODS: Outbreaks reported in Osaka City between 2008 and 2014 were investigated. The index cases were examined according to category group, sex, age, chest radiograph findings, sputum smear examination, patient delay, doctor delay, total delay in case finding, and adherence to regular health examinations. As controls, 467 patients in Osaka City with newly registered sputum smear-positive pulmonary tuberculosis in 2011 were included. RESULTS: Thirteen outbreaks occurred. The group categories included enterprises (9 outbreaks), preparatory schools (2), a junior high school (1), and other (1). The group of index cases consisted of 12 men (92.3%) and one woman (7.7%), with a mean age of 39.1 years; 11 (84.6%) were 30 to 50 years of age. Their ages ranged from 15 to 54 years. Of the control group of patients with sputum smear-positive pulmonary tuberculosis, 69.2% were 60 years or older, with a mean age of 65.4 years. These results suggest that the index case group was significantly younger (p < 0.001). There were ten cases (76.9%) of patient delay (initial visit 2 months or more after onset), and 8 (61.5%) of total delay (diagnosed 3 months or more after onset). These rates were significantly higher than those in the control group (p < 0.001). There were regular health examinations in four cases; among those, one did not see a doctor and another did not receive further examination. Chest radiographs revealed cavities in 12 cases (92.3%). All sputum smears were positive, with grades of 1 + in one case (7.7%), 2 + in two cases (15.4%), and 3 + in 10 cases (76.9%). These cases had a significantly higher rate of smear positivity than those in the control group (p < 0.001). DISCUSSION: The index cases were predominantly male, in their prime, and had higher infectivity rates. These findings suggest the importance of preventing delays in case findings and receiving regular and adequate health examinations.

[PULMONARY TUBERCULOSIS TREATMENT OUTCOME AMONG FOREIGN NATIONALS RESIDING IN OSAKA CITY].

UNLABELLED: Abstract PURPOSE: In this study, we analyzed pulmonary tuberculosis treatment outcomes among foreign nationals of different backgrounds. METHODS: The research was conducted between January 2006 and December 2011. One hundred fifty nine foreign nationals residing in Osaka city had pulmonary tuberculosis during this period. Patients were grouped according to treatment outcomes. We conducted three different types of comparisons. First, we compared backgrounds of patients with treatment success or default. Second, backgrounds of patients who continued treatment in Japan or who moved overseas (transfer out) were compared. Third, treatment outcomes of foreign nationals between 20 and 39 years of age were compared with those of age-matched Japanese patients registered between 2010 and 2011. RESULTS: (1) The treatment outcomes were as follows: cured, 53 cases (33.3%); treatment completed, 55 cases (34.6 %); treatment failure, 0 cases (0.0%); treatment default, 14 cases (8.8%); moved overseas, 17 cases (10.7%); moved to another location inside Japan, 13 cases (8.2%); died, 6 cases (3.8%); and under treatment, 1 case (0.6%). (2) Comparison of treatment success and default among foreign nationals with pulmonary tuberculosis revealed a default rate among smear-negative cases of 14.5%, significantly higher than in smear-positive cases (2.1%; P < 0.05). (3) We compared backgrounds between foreign nationals with pulmonary tuberculosis who continued taking treatment in Japan and those who moved abroad (transfer out). The rate of overseas transfer out (44.4%) was higher among patients not covered by health insurance. This was significantly higher than among patients covered by public insurance or assistance (9.0%; P < 0.01). (4) Comparison of foreign and Japanese nationals between 20 and 39 years of age revealed a default rate in foreign nationals with pulmonary tuberculosis of 13.6%. This was significantly higher than that of Japanese patients (4.0%; P < 0.01). The rate of transfer out among foreign nationals with pulmonary tuberculosis was 19.1%, also significantly higher than that of Japanese patients (5.3%; P < 0.001). DISCUSSION: The rates of treatment default and transfer out among patients between 20 to 39 years of age were significantly higher among foreign nationals than in Japanese patients. Lack of knowledge about treatment and language problems may contribute to this finding. This suggests that adequate support and definitive directly observed treatment short-course programs are needed for foreign nationals. Patients who moved abroad (overseas transfer out) may also be ultimately categorized as treatment default. However, it is difficult to determine final treatment outcomes of patients who moved abroad. Further measures are needed to ensure that foreign nationals continue to receive treatment when they transfer overseas.

[RATES OF COMPLETION AND TREATMENT OUTCOMES FOR TYPE OF COMMUNITY DOTS].

AIM: To investigate the relationship between completion rates for community directly observed treatment short-course (DOTS) and treatment outcomes, according to implementation tactics, to improve the treatment outcomes. METHODS AND SUBJECTS: We evaluated 529 newly registered patients with smear-positive pulmonary tuberculosis who underwent community DOTS (checking medication at least once per week) during 2010 and 2011 in Osaka City. DOTS completion was defined as checking medication 3 times or more per month, with checking medication missed less than 3 consecutive times. DOTS was implemented using the following 4 tactics: healthcare staff visited the patients' home or workplace (visiting type), the patients visited a health and welfare center (HWC type), the patients visited a pharmacy (P type), or the patients visited an outpatient department at a medical center (MC type). Regarding treatment outcomes, resolution of the tuberculosis or treatment completion was defined as "successful treatment", and treatment failure or default was defined as "unsuccessful treatment". We then analyzed the DOTS completion rate for each DOTS implementation tactic. RESULTS: DOTS was completed in 417 (78.8%) of the 529 patients. The completion rates were 79.7%, 75.4%, 75.9%, and 81.3% for patients who underwent visiting (n= 394), HWC (n = 61), P (n = 58), and MC (n = 16) DOTS, respectively; no significant difference was observed. The mean ages for each group were 62.8 years, 53.6 years, 45.0 years, and 56.6 years for patients who underwent visiting, HWC, P, and MC DOTS, respectively; patients who underwent P DOTS were significantly younger (P < 0.001). Among the 4 groups, the visiting DOTS group had the lowest percentage of full-time employees (16.2%) and the highest percentage of unemployed individuals (67.3%). In contrast, the percentage of full-time employees was 63.8% and 50.0% in the P and MC DOTS groups, respectively. The P DOTS group had the lowest unemployment percentage (19.0%) among the 4 groups. Thus, a significant correlation existed between the DOTS implementation tactics and the presence/ absence of the patients' occupations (P < 0.001). Among the 417 patients who completed DOTS, 99.8% achieved successful treatment. Among the 112 patients who did not complete DOTS, 89.3% achieved successful treatment, and this success rate was significantly lower than that for the group who completed DOTS (P < 0.00 1). Among the visiting, HWC, and P DOTS groups, the completion of DOTS resulted in a high treatment success rate. DISCUSSION: Patients who completed DOTS achieved better treatment outcomes; therefore, it is important to provide patients with medication support until their tuberculosis is resolved. The P DOTS group contained a higher percentage of full-time employees and had a significantly lower mean age; this was likely because pharmacies are accessible at night and during the weekend. There was no significant difference in the DOTS completion rates according to implementation tactic, which suggests that it is important to assist patients with their medication according to their needs.

[TUBERCULOSIS SCREENING BY CHEST RADIOGRAPHY AMONG INTERNATIONAL STUDENTS AT JAPANESE LANGUAGE SCHOOLS IN OSAKA CITY].

PURPOSE: With a broader aim of controlling pulmonary tuberculosis (TB) among foreigners, here, we have reported the findings of chest radiography screening for TB among international students at Japanese language schools in Osaka city. METHODS: Between April 2011 and December 2013, 4,529 international students from 19 Japanese language schools in Osaka city underwent chest radiography for TB screening. The chest radiographs were studied in reference to the student's sex, age, nationality, and date of entry to Japan as well as any health conditions present at the time of screening. We further analyzed the bacterial information and pulmonary TB classification based on chest radiography findings of students who were identified to be positive for TB. Information on the implementation of health education was also gathered. RESULTS: The results revealed that 52.5% of the students who underwent chest radiography came from China, 20.3 % from South Korea, and 16.3% from Vietnam. Of the students, 52.9% were male and 47.1% were female. The median age of students was 23 years (range: 14-70 years). The median number of days from the first date of entry to Japan up until the radiography screening was 63 days. Based on the chest radiography findings, 71 students (1.6%) were suspected to have TB; however, further detailed examination confirmed that 19 students (0.4%) had active TB. This percentage is significantly higher than the 0.1% TB identification rate among residents in Osaka city of the same time period (P<0.001), which was also determined by chest radiography. The median age of the 19 TB positive patients was 23 years. Among them, 14 (73.7%) were male. The median time from the date of entry to Japan to the date of the chest radiography screening was 137 days. For 16 of those students, the entry to Japan was within 1 year of the radiography. Of the 19 TB positive patients, 16 (84.2%) did not have respiratory symptoms, 15 (79.0%) had sputum smear negative results, and 17 (89.5%) had no cavity. Health education was conducted in 11 schools (for a total of 12 times) in the 3-year period. A total of 257 language school staff and students attended the health education seminars. DISCUSSION: The identification rate of TB positive students in Japanese language schools was higher than that of the general residents in Osaka city. In addition, most of these students came to Japan within 1 year. It is also important to note that the majority of TB positive students had sputum smear negative results. This study proves that medical examination after entry to Japan would be useful for early detection of TB positive patients. Furthermore, it would be beneficial to conduct chest radiography screenings among students at language schools on a continuous basis. It is also necessary to provide health education to the staff and students in Japanese language schools. Effective methods of disseminating health education, especially on the topic of TB, should be considered.

[Evaluation of risk factors for failed/defaulted on treatment outcomes of pulmonary tuberculosis in Osaka City].

OBJECTIVE: In this study, we analyzed the relationship between the risk of discontinuing medication and patient outcomes. METHODS: Newly registered patients with pulmonary tuberculosis from Osaka City who required outpatient treatment in 2011 were included in the study. We assessed the number of patient cures and the number of patients who completed medication as outcomes for successful treatment and the number of failed treatments and the number of treatments that were discontinued by patients as outcomes for failed and discontinued treatments. As related factors, we examined the risk of discontinuing medication, implementation of directly observed treatments, short course (DOTS), and planned duration of treatment. To assess the risk of discontinuing medication, we examined the following medical risk factors: (1) drug resistance to isoniazid or rifampicin, (2) diabetes, (3) use of immunosuppressive/anticancer drugs, (4) use of adrenal corticosteroid, (5) artificial dialysis, (6) human immunodeficiency virus infection/acquired immunodeficiency syndrome, (7) liver damage, and (8) side effects. The social risk factors were (1) being without a fixed address at the time of registration, (2) a history of discontinuing treatment, (3) lack of assistance with medication, (4) being elderly and requiring nursing care, (5) alcohol/drug dependence, (6) serious mental disease, (7) financial problems, (8) lack of the awareness of being ill, (9) keeping irregular hours, and (10) others. RESULTS: We identified 568 cases of successful treatment and 41 cases of failed and discontinued treatment. Multiple logistic regression analysis was performed, with successful treatment considered as the dependent variable 0 and failed and discontinued treatment considered as the dependent variable 1. The medical/social risk factors, positive/negative sputum smear test results, the planned duration of treatment (6 months/9 months or more), and the implementation of B type or higher DOTS were included as independent variables. The significant medical risk factors were drug resistance to isoniazid or rifampicin, the use of immunosuppressive/anticancer drugs, and side effects, with odds ratios of 4.55, 4.68, and 2.68, respectively. Further, a planned duration of treatment of 9 months or more and the implementation of B type or higher DOTS were associated with odd ratios of 4.51 and 0.35, respectively. CONCLUSION: These results highlight the need to assess risk factors for discontinuing treatment and to adopt measures to overcome these factors, such as the type of DOTS being implemented, in each case.

[Tuberculosis contact investigation in hospitals].

OBJECTIVE: To contribute to measures against hospital-acquired infections by analyzing and evaluating tuberculosis contact investigations in hospitals. METHODS: This study included 202 tuberculosis cases between January 2010 and September 2011 in which contact investigations were requested from the Public Health Office in Osaka City. RESULTS: 1) To assess the necessity for contact investigation and the demographics of index cases, contact investigations were conducted for 66 of the 202 cases. Index cases with higher rates of contact investigation included those with "higher degree of sputum smear positivity," "respiratory symptoms," "period from hospitalization to tuberculosis diagnosis of 8 days or longer," and "high-risk procedures (including endotracheal intubation, endotracheal aspiration, and bronchofiberscopy)." 2) A total of 632 contact persons from the following professions underwent QuantiFERON-TB (QFT) testing: 59 doctors, 492 nurses, 60 other hospital staff members, and 21 patients, and the positive QFT rates were 18.6, 10.8, 13.3, and 14.3%, respectively. 3) Among the 66 index cases for which contact investigations were conducted, there were 0 QFT-positive contact persons in 37 cases (56.1%), 1 or more in 29 (43.9%), and 2 or more in 18 cases (27.3%). Assuming the dependent variable to be 0 and 1, respectively, for index cases with 0 and 2 or more QFT-positive contact persons, we performed a multiple logistic regression analysis with independent variables that included the presence or absence of high-risk procedures, period from hospitalization to diagnosis either within 7 days or 8 or more days, presence or absence of cough and cavity, and the degree of sputum smear positivity (1+/2+/3+). Among these variables, those significantly associated with cases with 1 and 2 or more QFT-positive persons included the "presence of high-risk procedures" and "period from hospitalization to diagnosis of 8 days or longer" (P < 0.05). DISCUSSION: Our results suggest that early diagnosis and appropriate responses during high-risk procedures may be necessary measures to prevent hospital-acquired infections.

[Medication support and treatment outcome in homeless patients with tuberculosis].

PURPOSE: We conducted a study on factors related to treatment outcome and medication support in homeless patients with tuberculosis. METHODS: Participants were 433 homeless patients with tuberculosis newly registered in Osaka City between 2007 and 2009. We investigated factors related to treatment outcome (e.g., length of hospital stay, scheduled duration of outpatient treatment, and type of DOTS). Controls were 3,047 non-homeless patients with pulmonary tuberculosis newly registered in Osaka City during the same period. RESULTS: Regarding medication support, 219 (70.4%) of the 311 patients with successful treatment received DOTS and completed the treatment during their hospital stay. Thirty-five (72.9%) of the forty-eight patients who did not complete treatment left the hospital at their own discretion, resulting in treatment failure/default. The rate of treatment failure/default in the homeless patients with pulmonary tuberculosis was 11.0%, significantly higher than that of non-homeless patients with pulmonary tuberculosis (6.5%; P < 0.001). Among the 102 patients receiving community DOTS, medication compliance occurred at least 5 days a week in 66 patients (64.7%) and treatments failed or were interrupted in 10 patients (9.8%). The mean hospital stay was 2.0 +/- 1.6 months in patients with failed/defaulted treatment and 4.4 +/- 2.5 months in those with successful treatment. The scheduled duration of outpatient treatment was 7.9 +/- 2.7 months in patients with failed/defaulted treatment and 3.6 +/- 2.1 months in those with successful treatment. Shorter length of hospital stay and longer scheduled duration of outpatient treatment were associated with a higher rate of treatment failure/default (P < 0.01). CONCLUSION: Homeless patients with tuberculosis had a higher rate of treatment failure/default, most likely due to leaving the hospital at their own discretion. Patients with successful treatment generally completed treatment during their hospital stay. In contrast, patients who received community DOTS after discharge from the hospital had a higher rate of treatment failure/default, despite receiving medication at least 5 days a week. This suggests the need for adequate support, particularly in patients with a shorter hospital stay and those with a longer scheduled duration of outpatient treatment.

Strengthened tuberculosis control programme and trend of multi-drug resistant tuberculosis rate in Osaka City, Japan.

Osaka City has the highest tuberculosis (TB) notification rates in Japan. In the period 1999-2003, the TB control programme was strengthened, and the Stop TB Strategy was implemented to reduce the number of notified cases. The objective of this study was to assess the effect of these control activities in Osaka City, including the implementation of directly observed treatment (DOT), by analysing TB surveillance and routinely collected data. We reviewed the surveillance data of all sputum smear-positive pulmonary tuberculosis (PTB) cases registered in the Osaka City Public Health Office from 2001 to 2008 and data collected from the routine TB programme. The DOT implementation rate increased from 0% in 2001 to 68% in 2008 for smear-positive PTB cases of the general public and to 61% for all PTB cases of the homeless. The proportion of smear-positive PTB cases that had treatment failure and default combined, declined from 8.0% (52 of 650) in 2001 to 3.6% (20 of 548) in 2006. The proportion of cases among the homeless with previous treatment declined from 28% in 2001 to 15% in 2008. The proportion of cases with multidrug resistant-TB (MDR-TB) among those without previous treatment declined from 1.7% in 2001 to 0.9% in 2008. It is logical that reduction in the failure and default rate would lead to the reduction of cases with previous treatment and TB transmission, including resistant TB, therefore to the reduction of MDR-TB rates.

[Clustering analysis of Mycobacterium tuberculosis using the JATA(12)-VNTR system for molecular epidemiological surveillance in broad areas of Japan].

OBJECTIVES: Japan Anti-Tuberculosis Association (JATA) (12)-variable numbers of tandem repeats (VNTR) is a standard method for genotyping of clinical isolates of Mycobacterium tuberculosis in Japan. As a model study for nationwide surveillance, this study aimed to describe the tendency and frequency of genotypes of M. tuberculosis in a large number of clinical samples. METHODS: Clinical isolates of M. tuberculosis (n = 1,778) were obtained from patients with tuberculosis in 3 areas, i.e., Osaka City, Osaka Prefecture, and Kobe City, during 2007 and 2008. The samples were analyzed using JATA (12)-VNTR. All genotypes were subjected to clustering analysis. RESULTS AND DISCUSSION: In total, 1,086 (61.1%) isolates showed clustering. The most common clusters were composed of 3 members. Such clusters were considered to reflect either actual transmission or low discriminatory power of JATA (12)-VNTR. Several prevalent JATA(12)-VNTR genotypes formed large clusters and were discussed in relation with epidemiological findings of other studies. The findings of this study will aid in the construction of an effective genotyping-based surveillance system of M. tuberculosis, through improvement of interpretation of VNTR types, observation of certain particular strains in an area, and efficient detection of unidentified outbreaks.

[Interpreting "equivocal" results obtained from the QuantiFERON-TB Gold In-Tube test in contact investigations].

OBJECTIVE: In this study, we demonstrate the interpretation of "equivocal" results by the QuantiFERON"-TB Gold In-Tube (QFT-GIT) test in contact investigations. METHODS: The participants of the contact examinations were assessed by the QFT-GIT test after 2 to 4 months from the last contact with smear-positive tuberculosis patients. The study was conducted between April 2011 and March 2012. We enrolled 79 contact participants whose QFT-GIT tests produced equivocal results. RESULTS: The average age of the enrolled contacts was 35.9 years and the average interval from the last contact to the first QFT-GIT test was 85.4 days (range 62-118 days). The second QFT-GIT test produced negative results in 42 (53%) participants, equivocal results in 28 (35%), and positive results in 9 (11%). These 9 positive contacts belonged to the group of contacts with an index case whose QFT-GIT positive rate was more than 15%. The contacts belonging to groups with a QFT positive rate higher than 15% in the initial test had significantly higher QFT positive rates in the follow-up test than those belonging to groups with lower initial QFT positive rates (p=0.011). CONCLUSIONS: After retesting contacts with initially equivocal QFT results, 65% demonstrated either negative or positive results. If a contact's second QFT-GIT test is positive, it is highly probable that he/she is infected with tuberculosis and adequate treatment for latent TB infection is indicated. Thus far, no guidelines have been established for the management of contacts with equivocal results by the QFT-GIT test; therefore, further investigations and discussions are mandatory.

Influence of the 2009 financial crisis on detection of advanced pulmonary tuberculosis in Osaka city, Japan: a cross-sectional study.

OBJECTIVE: To investigate the association between the economic recession and the detection of advanced cases of pulmonary tuberculosis in Osaka city from 2007 to 2009. DESIGN: A repeated cross-sectional study. SETTING: Osaka city has been the highest tuberculosis burden area in Japan. After the previous global financial crisis, the unemployment rate in Osaka prefecture has deteriorated from 5.3% in 2008 to 6.6% in 2009. PARTICIPANTS: During the study period, 3406 pulmonary tuberculosis cases were enrolled: 2530 males and 876 females; 1546 elderly cases (65 years and above) and 1860 young cases (under 65 years); 417 homeless cases and 2989 non-homeless cases. OUTCOME MEASURES: Patients' information included the sex, age, registry, health insurances, places of detection, sputum smear test results, patients' delay, doctors' delay and the grade of chest x-ray findings. They were statistically analysed between 2007 and 2008, two years before and just before the financial crisis, and between 2008 and 2009, just before and after the financial crisis. RESULTS: The total numbers of pulmonary tuberculosis cases were 1172 in 2007, 1083 in 2008 and 1151 in 2009. In health examinations for non-homeless people, higher number of cases in 2009 were sputum smear positive, had respiratory symptoms and showed advanced disease in chest x-rays than those in 2008, with a longer patients' delay. On the contrary, in health examination for homeless people, fewer cases of advanced pulmonary tuberculosis were found in 2009 than in 2008, with a shorter patients' delay. In clinical examinations, there was no trend towards a difference between non-homeless and homeless people. CONCLUSIONS: Although homeless people might be protected by public assistance, tuberculosis prevention and control need to be reinforced for the non-homeless population after the financial crisis.