Diagnosis of Active Pulmonary Tuberculosis and Community Acquired Pneumonia Using Convolution Neural Network Based on Transfer Learning

RATIONALE AND OBJECTIVES

A convolutional neural network (CNN) model for the diagnosis of active pulmonary tuberculosis (APTB) and community-acquired pneumonia (CAP) using chest radiographs (CRs) was constructed and verified based on transfer learning.

MATERIALS AND METHODS

CRs of 1247 APTB cases, 1488 CAP cases and 1247 normal cases were collected. All CRs were randomly divided into training set (1992 cases), validation set (1194 cases) and test set (796 cases) by stratified sampling in 5:3:2 radio. After normalization of CRs, the convolution base of pre-trained CNN (VGG16) model on ImageNet dataset was used to extract features, and the grid search was used to determine the optimal classifier module, which was added to the convolution base for transfer learning. After the training, the model with the highest accuracy of the validation set was selected as the optimal model to verify in the test set and calculate the accuracy of the model.

RESULTS

The accuracy of validation set in the 63rd epochs was the highest, which was 0.9430, and the corresponding Categorical crossentropy was 0.1742. The accuracy of the training set was 0.9428, and the Categorical crossentropy was 0.1545. When the optimal model was applied to the test set, the accuracy was 0.9447, and the Categorical crossentropy was 0.1929.

CONCLUSION

The transfer learning-based CNN model has good classification performance in the diagnosis of APTB, CAP and normal patients using CRs.

Reproducibility of a protocol for standardized reading of chest X-rays of children household contact of patients with tuberculosis

BACKGROUND

The interpretation of the chest radiograph may vary because it depends on the reader and due to the non-specificity of findings in tuberculosis (TB). We aim to assess the reproducibility of a standardized chest radiograph reading protocol in contacts of patients with pulmonary TB under the 5 years of age.

METHODS

Descriptive, cross-sectional study with children under the age of five, household contacts of patients with confirmed pulmonary TB from Medellín, Bello and Itagüí (Colombia) between Jan-01-2015 and May-31-2016. Standardized reading protocol: two radiologists, blinded independent reading, use of template (Dr. Andronikou design) in case of disagreement a third reading was performed. Kappa coefficient for intra and inter observer agreement, and prevalence ratio were estimated of sociodemographic characteristics, TB exposure and interpretation of chest X-ray.

RESULTS

From 278 children, standardized reading found 255 (91.7%) normal X-rays, 10 (3.6%) consistent with TB, and 13 (4.7%) other alterations. Global agreement was 91.3% (Kappa = 0.51). Inter-observer agreement between readers 1-2 was 90.0% (Kappa = 0.59) and 1-3 93.2% (Kappa = 0.59). Intra-observer agreement for reader 1 was 95.5% (Kappa = 0.86), 2 84.0% (Kappa = 0.51), and 3 94.7% (Kappa = 0.68). Greater inter-observer disagreement was between readers 1-2 for soft tissue density suggestive of adenopathy (4.6%), airspace opacification (1.17%) and pleural effusion (0.58%); between readers 1-3 for soft tissue density suggestive of adenopathy (4.2%), opacification of airspace (2.5%) and cavities (0.8%).

CONCLUSIONS

Chest radiographs are an affordable tool that contributes to the diagnosis of TB, so having a standardized reading protocol showed good agreement and improves the reproducibility of radiograph interpretation.

Risk of infection and disease progression in children exposed to tuberculosis at home, Colombia

Aim:

To assess the risk of tuberculosis (infection and disease) in children less than 15 years’ old who are household contacts of pulmonary tuberculosis patients in three Colombian cities (Medellín, Cali, and Popayán).

Methods:

A cohort of 1,040 children household contacts of 380 adults with smear-positive pulmonary tuberculosis was followed up for 24 months. Study period 2005-2009.

Results:

Tuberculin skin test was positive (≥10 mm) in 43.7% (95% CI: 39.2-48.2). Tuberculin skin test positivity was associated with age 10-14 years (Prevalence Ratio -PR= 1.43, 95% CI: 1.1-1.9), having a BCG vaccine scar (PR= 1.52, 95% CI: 1.1-2.1), underweight, closer proximity to the index case and exposure time >3 months. The annual risk of infection (tuberculin skin test induration increase of 6 mm or more per year) was 17% (95% CI: 11.8-22.2) and was associated with a bacillary load of the adult index case (Relative Risk -RR= 2.12, 95% CI: 1.0-4.3). The incidence rate of active tuberculosis was 12.4 cases per 1,000 persons-year. Children <5 years without BCG vaccine scar had a greater risk of developing active disease (Hazard Ratio -HR= 6.00, 95% CI: 1.3-28.3) than those with scar (HR= 1.33, 95% CI: 0.5-3.4). The risk of developing active tuberculosis augmented along with the increase from initial tuberculin skin test (tuberculin skin test 5-9 mm HR= 8.55, 95% CI: 2.5-29.2; tuberculin skin test ≥10 mm HR= 8.16, 95% CI: 2.0-32.9).

Conclusions:

There is a need for prompt interruption of adult-to-children tuberculosis transmission within households. Conducting proper contact investigation and offering chemoprophylaxis to infected children could reduce tuberculosis transmission.

Pulmonary Tuberculosis Reactivation: Triggered by the Descent in Altitude?

High altitudes are linked to decreased rates of pulmonary tuberculosis infection, disease and mortality. However, its relevance as a trigger for pulmonary tuberculosis reactivation in immunocompetent patients is not documented. A 28-year-old healthy Nepalese female was admitted in the emergency department with sudden left pleuritic back pain with shortness of breath, two weeks after arriving in Lisbon, having arrived from Kathmandu and undergone a change in altitude of 1400 metres. She also had evening low-grade fever and fatigue since she arrived. Her mother-in-law had died of tuberculosis two years before. Chest radiography and computed tomography scan showed a left upper lobe consolidation. Laboratory analyses were 79 mm/sec. Human immunodeficiency virus serology, blood cultures and urinary antigen testing were negative. Bronchial secretions' cultures became positive for Mycobacterium tuberculosis complex. The patient was started on anti-tuberculous treatment and made a steady recovery. This case reports a probable reactivation of pulmonary tuberculosis infection that could have been triggered by altitude differences.

[Fatal Hemoptysis]

N/A.

Duration of Pulmonary Tuberculosis Infectiousness under Adequate Therapy, as Assessed Using Induced Sputum Samples

Background

A sputum culture is the most reliable indicator of the infectiousness of pulmonary tuberculosis (PTB); however, a spontaneous sputum specimen may not be suitable. The aim of this study was to evaluate the infectious period in patients with non–drug-resistant (DR) PTB receiving adequate standard chemotherapy, using induced sputum (IS) specimens.

Methods

We evaluated the duration of infectiousness of PTB using a retrospective cohort design.

Results

Among the 35 patients with PTB, 22 were smear-positive. The rates of IS culture positivity from baseline to the sixth week of anti-tuberculosis medication in the smear-positive PTB group were 100%, 100%, 91%, 73%, 36%, and 18%, respectively. For smear-positive PTB cases, the median time of conversion to culture negativity was 35.0 days (range, 28.0–42.0 days). In the smear-negative PTB group (n=13), the weekly rates of positive IS culture were 100%, 77%, 39%, 8%, 0%, and 0%, respectively, and the median time to conversion to culture-negative was 21.0 days (range, 17.5–28.0 days).

Conclusion

The infectiousness of PTB, under adequate therapy, may persist longer than previously reported, even in patients with non-DR PTB.

Association of Serum Vitamin D Levels with Bacterial Load in Pulmonary Tuberculosis Patients

Background

Vitamin D is known to have diverse effects on various systems in the body. There is evidence to suggest that a link exists between the serum vitamin D status and tuberculosis. The present study was designed to assess the alterations in serum 25-hydroxyvitamin D levels in newly diagnosed sputum acid fast bacilli (AFB) positive pulmonary tuberculosis patients and to study the association, if any, between serum vitamin D levels and different levels of sputum smear positivity.

Methods

Serum 25-hydroxyvitamin D levels were estimated in 65 sputum AFB positive pulmonary tuberculosis patients and 65 age and gender-matched healthy controls.

Results

The levels of serum 25 hydroxy-vitamin D in tuberculosis patients were not statistically different from the levels of serum 25 hydroxy-vitamin D in healthy controls. However, among patients with pulmonary tuberculosis, there was a significant negative correlation between the levels of serum 25 hydroxy-vitamin D and levels of sputum positivity.

Conclusion

Serum vitamin D levels negatively correlates with bacterial load in patients with active pulmonary tuberculosis.

Intention to Quit Smoking and Associated Factors in Smokers Newly Diagnosed with Pulmonary Tuberculosis

BACKGROUND

Several studies have shown that smoking, as a modifiable risk factor, can affect tuberculosis (TB) in different aspects such as enhancing development of TB infection, activation of latent TB and its related mortality. Since willingness to quit smoking is a critical stage, which may lead to quit attempts, being aware of smokers' intention to quit and the related predictors can provide considerable advantages.

MATERIALS AND METHODS

In this cross-sectional study, subjects were recruited via a multi-stage cluster sampling method. Sampling was performed during 2012-2014 among pulmonary TB (PTB) patients referred to health centers in Tehran implementing the directly observed treatment short course (DOTS) strategy and a TB referral center. Data analysis was conducted using SPSS version 22 and the factors influencing quit intention were assessed using bivariate regression and multiple logistic regression models.

RESULTS

In this study 1,127 newly diagnosed PTB patients were studied; from which 284 patients (22%) were current smokers. When diagnosed with TB, 59 (23.8%) smokers quit smoking. Among the remaining 189 (76.2%) patients who continued smoking, 52.4% had intention to quit. In the final multiple logistic regression model, living in urban areas (OR=8.81, P=0.003), having an office job (OR= 7.34, P=0.001), being single (OR=4.89, P=0.016) and a one unit increase in the motivation degree (OR=2.60, P<0.001) were found to increase the intention to quit smoking.

CONCLUSION

The study found that PTB patients who continued smoking had remarkable intention to quit. Thus, it is recommended that smoking cessation interventions should be started at the time of TB diagnosis. Understanding the associated factors can guide the consultants to predict patients' intention to quit and select the most proper management to facilitate smoking cessation for each patient.

Efficacy of Induced Sputum for the Diagnosis of Pulmonary Tuberculosis in Adults Unable to Expectorate Sputum

Background

Induced sputum (IS) has been used to collect airway secretions in subjects who have inadequate sputum production. The aim of this study was to investigate the efficacy of IS for the diagnosis of pulmonary tuberculosis (PTB) in adults unable to expectorate sputum.

Methods

Medical records of 39 PTB patients who underwent IS due to absence of spontaneous sputum production between January 2011 and March 2014 at a tertiary hospital in South Korea were reviewed. Results of acid fast bacilli smear, Mycobacterium tuberculosis culture and polymerase chain reaction assay for M. tuberculosis (TB-PCR) of IS specimens from these patients were analyzed. Clinical and high-resolution computed tomography (HRCT) characteristics were also analyzed to find characteristics associated with IS culture positivity.

Results

Of the 39 IS specimens from PTB patients, 7 (17.9%) were smear positive and 31 (79.5%) were culture positive. Twenty-four IS specimens were tested for TB-PCR and 13 (54.2%) were positive on TB-PCR. Multivariate analysis showed that younger age (p=0.04) and presence of tree-in-bud appearance on HRCT (p=0.03) were independent predictors of IS culture positivity.

Conclusion

IS is useful for the diagnosis of PTB in adults unable to expectorate sputum. Younger age and tree-in-bud appearance on HRCT were associated with IS culture positivity in these patients.

Changes in Diagnostic Methods for Pulmonary Tuberculosis between 2005 and 2013

Background

Diagnostic methods for pulmonary tuberculosis (TB) have recently advanced. The aim of this study was to evaluate the changes in TB diagnostic tests that prompted the initiation of anti-TB treatment over time in South Korea, an industrialized country with an intermediate TB burden.

Methods

Patients diagnosed with pulmonary TB in the first halves of 2005 and 2013 at a tertiary referral hospital were included. Diagnostic methods that prompted the initiation of anti-TB treatment were compared between the 2 groups of patients.

Results

A greater proportion of patients were diagnosed with pulmonary TB using bronchoscopy in 2013 than in 2005 (26.7% vs. 6.6%, respectively; p<0.001), while the proportion of patients clinically diagnosed with pulmonary TB was lower in 2013 than in 2005 (24.7% vs. 49.0%, respectively; p<0.001). Additionally, more patients started anti-TB treatment based on positive polymerase chain reaction (PCR) results for Mycobacterium tuberculosis DNA in 2013 than in 2005 (47.3% vs. 7.9%, respectively; p<0.001).

Conclusion

The initiation of treatment for pulmonary TB in South Korea has become more frequently based on PCR and the use of bronchoscopic specimens.

Acceptability of sputum specimens for diagnosing pulmonary tuberculosis

The evaluation of the quality of a sputum specimen prior to bacterial culture has been an accepted practice. However, optimal sputum criteria for pulmonary tuberculosis (TB) are not well established. We investigated indicators for sputum acceptability in tuberculosis cultures and acid-fast bacilli (AFB) smear. A post-hoc analysis of a randomized trial with 228 sputum specimens from 77 patients was conducted. In the trial, pulmonary TB suspects were requested for collecting three sputum specimens. We performed both TB study (AFB smear and M. tuberculosis culture) and Gram staining in each specimen. By using generalized estimating equations, the association between sputum characteristics and positive TB testings were analyzed. Although acceptable specimens for bacterial pneumonia showed higher TB-culture positive rates than unacceptable specimens (adjusted odds ratio [aOR]=1.66; 95% confidence interval [CI]=1.11-2.49), a specimen with ≥25 white blood cells/low-power field was the better predictor for positive M. tuberculosis cultures (aOR=2.30; 95% CI=1.48-3.58) and acid-fast bacilli smears (aOR=1.85; 95% CI=1.05-3.25). Sputum leukocytosis could be an indicator of sputum acceptability for diagnosing pulmonary tuberculosis.

Agranulocytosis induced by ethambutol in a patient with pulmonary tuberculosis

We report a case of agranulocytosis caused by ethambutol in a 79-year-old man with pulmonary tuberculosis. He was referred for fever and skin rash developed on 21th day after antituberculosis drugs (isoniazid, rifampicin, ethambutol, and pyrazinamide) intake. Complete blood count at the time of diagnosis of pulmonary tuberculosis was normal. On the seventh admission day, agranulocytosis was developed with absolute neutrophil count of 70/µL. We discontinued all antituberculosis drugs, and then treated with granulocyte colony-stimulating factor. Three days later, the number of white blood cell returned to normal. We administered isoniazid, pyrazinamide, and ethambutol in order with an interval. However, fever and skin rash developed again when adding ethambutol, so we discontinued ethambutol. After these symptoms disappeared, we added rifampicin and ethambutol in order with an interval. However after administering ethambutol, neutropenia developed, so we discontinued ethambutol again. He was cured with isoniazid, rifampicin, and pyrazinamide for 9 months.

The effectiveness of real-time PCR assay, compared with microbiologic results for the diagnosis of pulmonary tuberculosis

Background

The incidence of tuberculosis (TB) in Korea is relatively high compared to the other Organisation for Economic Co-operation and Development (OECD) countries, with a prevalence of 71 per 100,000 in 2012, although the incidence is declining. Real-time polymerase chain reaction (PCR) has been introduced for the rapid diagnosis of TB. Recently, its advantage lies in higher sensitivity and specificity for the diagnosis of TB. This study evaluated the clinical accuracy of real-time PCR using respiratory specimens in a clinical setting.

Methods

Real-time PCR assays using sputum specimens and/or bronchoscopic aspirates from 2,877 subjects were reviewed retrospectively; 2,859 subjects were enrolled. The diagnosis of TB was determined by positive microbiology, pathological findings of TB in the lung and pleura, or clinical suspicion of active TB following anti-TB medication for more than 6 months with a favorable response.

Results

Sensitivity, specificity, and accuracy were 44%, 99%, and 86% from sputum, and 65%, 97%, and 87% from bronchoscopic aspirates, respectively. For overall respiratory specimens, sensitivity was 59%, specificity was 98%, and accuracy increased to 89%.

Conclusion

Positivity in real-time PCR using any respiratory specimens suggests the possibility of active TB in clinically suspected cases, guiding to start anti-TB medication. Real-time PCR from selective bronchoscopic aspirates enhances the diagnostic yield much more when added to sputum examination.

Risk factors for death during pulmonary tuberculosis treatment in Korea: a multicenter retrospective cohort study

The data regarding risk factors for death during tuberculosis (TB) treatment are inconsistent, and few studies examined this issue in Korea. The purpose of this study was to evaluate baseline prognostic factors for death during treatment of adult patients with pulmonary TB in Korea. A multicenter retrospective cohort study of 2,481 patients who received TB treatment at eight hospitals from January 2009 to December 2010 was performed. Successful treatment included cure (1,129, 45.5%) and treatment completion (1,204, 48.5%) in 2,333 patients (94.0%). Unsuccessful treatment included death (85, 3.4%) and treatment failure (63, 2.5%) occurred in 148 patients (6.0%). In multivariate analysis, male sex, anemia, dyspnea, chronic heart disease, malignancy, and intensive care unit (ICU) admission were significant risk factors for death during TB treatment. Therefore, male sex, anemia, dyspnea, chronic heart disease, malignancy, and ICU admission could be baseline prognostic factors for death during treatment of adult patients with pulmonary TB in Korea.

Takotsubo cardiomyopathy caused by pulmonary tuberculosis: a case report

Takotsubo cardiomyopathy (TTC) is defined as a reversible, acute ventricular dysfunction without any evidence of coronary artery obstruction. There have been reports of TTC caused by emotional or physical stress, drug use, hormone imbalance, or medical conditions such as pulmonary disease, sepsis, and trauma, but a relationship between TTC and pulmonary tuberculosis has not previously been reported. From our knowledge, this is the first report of TTC caused by pulmonary tuberculosis.

Diagnosis of pulmonary tuberculosis and nontuberculous mycobacterial lung disease in Korea

The recovery of nontuberculous mycobacteria (NTM) from respiratory specimens and the number of patients with NTM lung disease have been rapidly increasing in Korea. An early differential diagnosis of NTM lung disease from pulmonary tuberculosis (TB) is important, as the therapeutic regimen differs from that of pulmonary TB, and it is not necessary to track the contacts of patients with NTM lung disease. However, differentiating NTM lung disease from pulmonary TB remains difficult, because the clinical presentations of the two diseases are similar and a definite diagnosis of NTM lung disease based on sputum culture takes time. This review focuses on the changing epidemiology, clinical and radiographic manifestation, and laboratory diagnosis of pulmonary TB and NTM lung disease in Korea.

Usefulness of sputum induction with hypertonic saline in a real clinical practice for bacteriological yields of active pulmonary tuberculosis

Background

Mycobacterial identification in active pulmonary tuberculosis (APTB) is confirmative, even though successful rates using self-expectorated sputum are limited. Sputum specimens collected by hypertonic saline nebulization showed higher bacteriologic diagnostic sensitivities over those of self-expectoration, mostly studied in smear-negative or sputum-scarce patients. The efficacy of induced sputum was rarely assessed in real clinical settings.

Methods

A prospective randomized case-control study was performed in one hospital. The subjects highly suspicious of APTB were asked to provide 3 pairs of sputum specimens in 3 consecutive days. The first pairs of the specimens were obtained either by self-expectoration (ES) from the next day of the visit or sputum induction with 7% saline nebulization in clinic (SI), and the other specimens were collected in the same way. The samples were tested in microscopy, culture, and polymerase chain reaction (PCR). The outcomes of the bacteriological diagnosis were compared.

Results

Seventy six patients were assigned to either ES (38 subjects, median age of 51, 65.8% male) or SI (38 subjects, median age of 55, 52.6% male). APTB was clinically confirmed in 51 patients (70.8%), 27 in ES and 24 in SI. Among the APTB, more adequate specimens were collected from SI (41/65, 63.1%) than ES (34/80, 42.5%) (p=0.01). Bacteriological confirmation was achieved in 14 (58.3%) patients in SI, and 13 (48.1%) in ES (p=0.46). In the same-day bacteriological diagnosis with microscopy and PCR, there were positive results for 9 patients (37.5%) in SI and 7 patients (25.9%) in ES (p=0.37).

Conclusion

Sputum induction improves sputum specimen adequacy. It may be useful for the same-day bacteriological diagnosis with microscopic examination and PCR.

(18)F-FDG positron-emission tomography/computed tomography findings of radiographic lesions suggesting old healed tuberculosis

The presence of radiographic lesions suggesting old healed tuberculosis (TB) is one of the strongest risk factors for the subsequent development of active TB. We elucidated the metabolic activity of radiographic lesions suggesting old healed TB using (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT). This cross-sectional study included 63 participants with radiographic lesions suggesting old healed TB and with available (18)F-FDG PET/CT scans. The maximum standardized uptake value (SUVmax) measured in the lesions, the clinical characteristics, results of the tuberculin skin test (TST) and interferon-γ release assay (IGRA) were analyzed. The SUVmax in old healed TB was 1.5 or higher among nine (14.3%) participants. Age (adjusted odds ratio [aOR], 1.23; 95% CI, 1.03-1.46), history of previous TB (aOR, 60.43; 95% CI, 1.71-2131.65), and extent of the lesions (aOR, 1.34; 95% CI, 1.02-1.75) were associated with higher SUVmax. The positive rates for the TST and IGRA were not different between groups with and without increased FDG uptake. Increased FDG uptake on (18)F-FDG PET/CT was observed in a subset of patients with radiographic lesions suggesting old healed TB. Given that the factors associated with increased FDG uptake are known risk factors for TB development, the possibility exists that participants with old healed TB lesions with higher SUV on (18)F-FDG PET/CT scans might be at higher risk for active TB.

Mycobacterium intracellulare Pulmonary Disease with Endobronchial Caseation in a Patient Treated with Methotrexate

Methotrexate (MTX) has been established as a standard disease-modifying anti-rheumatic drug. If adequate disease control is achieved for a reasonable period of time, tapering the MTX dosage is recommended because the chronic use of MTX can result in opportunistic infection. We present here a case of a woman with rheumatoid arthritis taking MTX, and the woman developed actively caseating endobronchial Mycobacterium intracellulare disease with pulmonary infiltrations. After discontinuing the MTX, the patient was able to tolerate 18 months of antimycobacterial treatment without flare ups of rheumatoid arthritis, and she completely recovered from nontuberculous mycobacterial respiratory disease.

Pulmonary tuberculosis and lung cancer risk in current smokers: the Seoul Male Cancer Cohort Study

Authors evaluated pulmonary tuberculosis (PTB) history as a risk factor for lung cancer in current male smokers in a prospective, population-based cohort study. The subjects were the 7,009 males among the participants in the Seoul Male Cancer Cohort Study for whom there was full information on PTB history and smoking habits. With a 16-yr follow-up, 93 cases of lung cancer occurred over the 99,965 person-years of the study. The estimated relative risk (RR) of PTB history of current smokers in lung cancer after adjusting for three confounders - intake of coffee and tomatoes, and age at entry - was 1.85 (95% CI: 1.08-3.19). The observed joint RRs and attributable risks (ARs) across strata of three confounders were greater than the expected, indicating a positive interaction. Thus a history of PTB in current smokers may be another risk factor for lung cancer. Based on a synergic interaction, a heavy male smoker with a PTB history would be expected to belong to the group at high risk of lung cancer.

The clinical characteristics and predictors of treatment success of pulmonary tuberculosis in homeless persons at a public hospital in busan

BACKGROUND

Homelessness is associated with an increased risk of exposure to Mycobacterium tuberculosis. Several factors, including alcoholism, malnutrition, lack of stable housing, combine to make tuberculosis more prevalent in the homeless. The aims of this study were to determine the factors associated with increasing success rate of tuberculosis treatment in the homeless.

METHODS

A cross-sectional analysis of the clinical features in 142 pulmonary tuberculosis-positive homeless patients admitted to the Busan Medical Center from January 2001 to December 2010 was carried out. These results were compared with a successful treatment group and incomplete treatment group. We also evaluated the risk factors of treatment non-completion. Statistical analysis for the comparisons was performed using a χ(2) test, independent samples t-test, and multiple logistic regression.

RESULTS

Comparison of clinical characteristics showed significant differences between the two groups in the type of residence (P < 0.001), diseases with risk factors (P = 0.003), and history of tuberculosis treatment (P = 0.009). Multiple regression analysis revealed the residence (odds ratio [OR], 4.77; 95% confidence interval [CI], 2.05 to 11.10; P < 0.001) and comorbidity with risk factor (OR, 2.72; 95% CI, 1.13 to 6.53; P = 0.025) to be independently associated with treatment success.

CONCLUSION

To improve the success rate of tuberculosis treatment in the homeless person, anti tuberculosis medication should be taken until the end of treatment and a management system for the homeless person is required. Further social and medical concerns for stable housing and management of comorbidity may lead to an improvement in the successful tuberculosis treatment of homeless person.

Risk factors related with mortality in patient with pulmonary tuberculosis

Background

The prevalence rate of pulmonary tuberculosis (PTB) is steadily decreasing in South Korea. However, PTB is a disease with relatively high mortality and morbidity rates throughout Korea. Although there are many studies and statistics about the risk factors of PTB mortality in many countries, there are only a limited number of domestic papers on this topic. The aim of this study is to determine predictive factors for mortality among in-hospital patients associated with PTB.

Methods

From December 2006 to January 2011, we reviewed medical records of 2,122 adult patients diagnosed with tuberculosis at a single tertiary hospital in a suburban area. In this study period, 960 patients were diagnosed with PTB by positive Acid fast bacilli smear and/or mycobacterial culture of the respiratory specimen. We compared the groups of patients deceased and patients discharged alive with PTB. The number of dead patients was 82 (47 males, 35 females).

Results

Mortality was significantly associated with increased values of white blood cells (WBC), blood urine nitrogen (BUN), creatinine, C-reactive protein (CRP), numbers of involved lung field, and length of hospitalization. Also, it was associated with the decreased values of hemoglobin, lymphocyte, sodium, albumin, and cholesterol. Furthermore, admission through the emergency department, initial intensive care unit admission, and drug resistant PTB affected mortality in PTB patients. Independent predictors associated with PTB mortality are BUN, initial intensive care unit care, and admission during treatment of tuberculosis.

Conclusion

In our study, mortality of pulmonary tuberculosis was related with parameters associated with nutritional status, disease severity at the time of admission, and drug resistance.

Value of radiodensity determined by enhanced computed tomography for the differential diagnosis of lung masses

Background

Lung masses are often difficult to differentiate when their clinical symptoms and shapes or densities on computed tomography (CT) images are similar. However, with different pathological contents, they may appear differently on plain and enhanced CT.

Objectives

To determine the value of enhanced CT for the differential diagnosis of lung masses based on the differences in radiodensity with and without enhancement.

Patients and Methods

Thirty-six patients with lung cancer, 36 with pulmonary tuberculosis (TB) and 10 with inflammatory lung pseudotumors diagnosed by CT and confirmed by pathology in our hospital were selected. The mean ± SD radiodensities of lung masses in the three groups of patients were calculated based on the results of plain and enhanced CT.

Results

There were no significant differences in the radiodensities of the masses detected by plain CT among patients with inflammatory lung pseudotumors, TB and lung cancer (P > 0.05). However, there were significant differences (P < 0.01) between all the groups in terms of radiodensities of masses detected by enhanced CT.

Conclusions

The radiodensities of lung masses detected by enhanced CT could potentially be used to differentiate between lung cancer, pulmonary TB and inflammatory lung pseudotumors.

Multidrug-resistant pulmonary tuberculosis among young Korean soldiers in a communal setting

The goal of this study was to evaluate the prevalence of first-line anti-tuberculosis drug resistance and risk factors associated with multidrug-resistant tuberculosis (MDR TB) among young soldiers in the Korean military, which has a strict tuberculosis control program. All patients with culture-confirmed pulmonary tuberculosis during their service at the Armed Forces Capital Hospital from January 2001 to December 2006 were enrolled in the study. Drug resistant Mycobacterium tuberculosis was isolated from 18 patients (12.2%) and multidrug-resistant M. tuberculosis was isolated from 12 patients (8.1%). Previous treatment of tuberculosis and the presence of a cavity on the patient's chest computed tomography scan were associated with MDR TB; military rank, smoking habits, and positive acid-fast bacilli smears were not associated with MDR TB. In a multiple logistic regression analysis, previous treatment of tuberculosis was a significant independent risk factor for MDR TB (odds ratio 6.12, 95% confidence interval 1.53-24.46). The prevalence of drug resistant tuberculosis among young soldiers in the Korean military was moderately high and the majority of resistant cases were found in patients who had undergone previous treatment of tuberculosis. Based on our results, we suggest that relapsed tuberculosis cases within communal settings should be cautiously managed until the drug susceptibility tests report is completed, even if previous treatment results were satisfactory.