Diagnostic accuracy of notified cases as pulmonary tuberculosis in private sectors of Korea

Prevalence of pre-existing lung diseases and their association with income level among patients with lung cancer: a nationwide population-based case-control study in South Korea

BACKGROUND

This study aimed to estimate the prevalence of pre-existing lung diseases in patients with lung cancer compared to people without lung cancer and examine the association between income levels and pre-existing lung diseases.

METHODS

Data on patients with lung cancer (case) and the general population without lung cancer (non-cancer controls) matched by age, sex and region were obtained from the Korea National Health Insurance Service-National Health Information Database (n=51 586). Insurance premiums were divided into quintiles and medicaid patients. Conditional logistic regression models were used to examine the association between pre-existing lung diseases and the risk of lung cancer. The relationship between income level and the prevalence of pre-existing lung disease among patients with lung cancer was analysed using logistic regression models.

RESULTS

The prevalence of asthma (17.3%), chronic obstructive lung disease (COPD) (9.3%), pneumonia (9.1%) and pulmonary tuberculosis (1.6%) in patients with lung cancer were approximately 1.6-3.2 times higher compared with the general population without lung cancer. A significantly higher risk for lung cancer was observed in individuals with pre-existing lung diseases (asthma: OR=1.36, 95% CI 1.29 to 1.44; COPD: 2.11, 95% CI 1.94 to 2.31; pneumonia: 1.49, 95% CI 1.38 to 1.61; pulmonary tuberculosis: 2.16, 95% CI 1.75 to 2.66). Patients with lung cancer enrolled in medicaid exhibited higher odds of having pre-existing lung diseases compared with those in the top 20% income level (asthma: OR=1.75, 95% CI 1.56 to 1.96; COPD: 1.91, 95% CI 1.65 to 2.21; pneumonia: 1.73, 95% CI 1.50 to 2.01; pulmonary tuberculosis: 2.45, 95% CI 1.78 to 3.36).

CONCLUSIONS

Pre-existing lung diseases were substantially higher in patients with lung cancer than in the general population. The high prevalence odds of pre-existing lung diseases in medicaid patients suggests the health disparity arising from the lowest income group, underscoring a need for specialised lung cancer surveillance.

The burden of tuberculosis among adolescents and young adults in five Asian countries from 1990 to 2019

BACKGROUND

Previous studies have shown that the risk of tuberculosis (TB) increases dramatically during adolescence. The objective of this article was to analyze the burdens and trends of TB incidence and mortality rates in Asian adolescents and young adults.

METHODS

Time series ecological study of TB incidence and mortality rates of adolescents and young adults aged 10-24 years from 1990 to 2019, using data extracted from the Global Burden of Disease website for 5 Asian countries. The annual percentage change was calculated by joinpoint regression analysis to estimate the trends in the age-standardized incidence rate (ASIR) and age-standardized death rate (ASDR).

RESULTS

The highest ASIR per 100,000 person-years in 2019 was in Mongolia [74 (95% uncertainty interval (UI), 51 to 105)], while the lowest was in Japan [4 (95% UI, 2 to 6)]. The highest ASDR per 100,000 person-years was in Mongolia [2 (95% UI, 1 to 3)], while the lowest was in Japan [0.009 (95% UI, 0.008 to 0.010)]. As the absolute number of cases and deaths decreased from 1990 to 2019, the ASIRs and ASDRs in all five countries also decreased.

CONCLUSIONS

Our finding revealed that although all five countries in Asia experienced descending TB incidence and mortality trend in past three decades, the trends were especially significant in developed countries and varied across geographic regions. This study may be crucial in helping policymakers make decisions and allocate appropriate resources to adolescent TB control strategies.

Nationwide Treatment Outcomes of Patients With Multidrug/Rifampin-Resistant Tuberculosis in Korea, 2011-2017: A Retrospective Cohort Study (Korean TB-POST)

BACKGROUND

The treatment outcomes of patients with multidrug/rifampin-resistant (MDR/RR) tuberculosis (TB) are important indicators that reflect the current status of TB management and identify the key challenges encountered by TB control programs in a country.

METHODS

We retrospectively evaluated the treatment outcomes as well as predictors of unfavorable outcomes in patients with MDR/RR-TB notified from 2011 to 2017, using an integrated TB database.

RESULTS

A total of 7,226 patients with MDR/RR-TB were included. The treatment success rate had significantly increased from 63.9% in 2011 to 75.1% in 2017 (P < 0.001). Among unfavorable outcomes, the proportion of patients who failed, were lost to follow up, and were not evaluated had gradually decreased (P < 0.001). In contrast, TB-related death rate was not significantly changed (P = 0.513), while the non-TB related death rate had increased from 3.2% in 2011 to 11.1% in 2017 (P < 0.001). Older age, male sex, immigrants, low household income, previous history of TB treatment, and comorbidities were independent predictors of unfavorable outcomes. Of the 5,308 patients who were successfully treated, recurrence occurred in 241 patients (4.5%) at a median 18.4 months (interquartile range, 9.2-32.4) after completion treatment.

CONCLUSION

The treatment outcomes of patients with MDR/RR-TB has gradually improved but increasing deaths during treatment is an emerging challenge for MDR-TB control in Korea. Targeted and comprehensive care is needed for vulnerable patients such as the elderly, patients with comorbidities, and those with low household incomes.

Pre-immigration Screening for Tuberculosis in South Korea: A Comparison of Smear- and Culture-Based Protocols

BACKGROUND

Tuberculosis (TB) is the most important disease screened for upon patient history review during preimmigration medical examinations as performed in South Korea in prospective immigrants to certain Western countries. In 2007, the U.S. Centers for Disease Control and Prevention (CDC) changed the TB screening protocol from a smear-based test to the complete Culture and Directly Observed Therapy Tuberculosis Technical Instructions (CDOT TB TI) for reducing the incidence of TB in foreign-born immigrants.

METHODS

This study evaluated the effect of the revised (as compared with the old) protocol in South Korea.

RESULTS

Of the 40,558 visa applicants, 365 exhibited chest radiographic results suggestive of active or inactive TB, and 351 underwent sputum tests (acid-fast bacilli smear and Mycobacterium tuberculosis culture). To this end, using the CDOT TB TI, 36 subjects (88.8 per 10⁵ of the population) were found to have TB, compared with only seven using the older U.S. CDC technical instruction (TI) (p<0.001). In addition, there were six drug-resistant cases which were identified (16.7 per 10⁵ of the population), two of whom had multidrug-resistance (5.6 per 10⁵ of the population).

CONCLUSION

The culture-based 2007 TI identified a great deal of TB cases current to the individuals tested, as compared to older U.S. CDC TI.

Frequncy and etiology of lymphadenopathy in Iranian HIV/AIDS patients

OBJECTIVE

To estimate and outline the frequency and etiology of lymphadenopathy in HIV/AIDS patients.

METHODS

This study was conducted on 178 consecutive HIV/AIDS patient files for etiologies (categorized into three sub-groups: definite, probable and possible) and associated factors of local and generalized lymphadenopathy.

RESULTS

Seventy-two (40.45%) patients including 63 male patients (87.5%) developed lymphadenopathy. HIV in lymphadenopathy(+) patients was most commonly transmitted intravenously (n=49). Generalized and localized lymphadenopathy respectively occurred in 27 (37.50%) and 45 (62.50%) patients, mainly in the cervical region (28.9% for local and 63% for generalized lymphadenopathy). The most common causes of lymphadenopathy were tuberculosis (n=24, 33.3%) and lymphoma (n=12, 16.6%). The frequency of lymphadenopathy was non-significantly higher in patients with AIDS (CD4 count <200 cell/µL) vs. HIV(+) patients (CD4 count >200 cell/µL).

CONCLUSIONS

Lymphadenopathy in HIV/AIDS patients may reflect a serious condition, most likely tuberculosis and lymphoma. Since patients might underestimate lymphadenopathy, physicians would rather list these entities for diagnosis.

Causes and predictive factors associated with "diagnosis changed" outcomes in patients notified as tuberculosis cases in a private tertiary hospital

Background

The aim of our study was to evaluate the "diagnosis changed" rate in patients notified as tuberculosis (TB) on the Korean TB surveillance system (KTBS).

Methods

A total of 1,273 patients notified as TB cases on the KTBS in one private tertiary hospital in 2011 were enrolled in the present study. Patients were classified into three groups: "diagnosis maintained", "diagnosis changed" (initially notified as TB, but ultimately diagnosed as non-TB), and "administrative error" (notified as TB due to administrative errors).

Results

Excluding 17 patients in the "administrative error" group, the "diagnosis maintained" and "diagnosis changed" groups included 1,097 (87.3%) and 159 patients (12.7%), respectively. Common causes of "diagnosis changed" were nontuberculous mycobacterial (NTM) disease (51.7%, 61/118), and pneumonia (17.8%) in cases notified as pulmonary TB, and meningitis (19.5%, 8/41) and Crohn's disease (12.2%) in cases notified as extrapulmonary TB. Being older than 35 years of age (odds ratio [OR], 2.18) and a positive acid-fast bacilli stain (OR, 1.58) were positive predictors and a TB-related radiological finding (OR, 0.42) was a negative predictor for a "diagnosis changed" result via multivariate logistic regression analysis in pulmonary TB cases.

Conclusion

Because of a high "diagnosis changed" rate in TB notifications to the KTBS, the TB incidence rate measured by the KTBS may be overestimated. Considering the worldwide trend toward increased NTM disease, the "diagnosis changed" rate may increase over time. Thus, when reporting the annual TB notification rate in Korea, the exclusion of "diagnosis changed" cases is desirable.