High resolution chest CT in patients with pulmonary tuberculosis: Characteristic findings before and after antituberculous therapy

Predictive capabilities of baseline radiological findings for early and late disease outcomes within sensitive and multi-drug resistant tuberculosis cases

Purpose

This study compares performance of Timika Score to standardized, detailed radiologist observations of Chest X rays (CXR) for predicting early infectiousness and subsequent treatment outcome in drug sensitive (DS) or multi-drug resistant (MDR) tuberculosis cases. It seeks improvement in prediction of these clinical events through these additional observations.

Method

This is a retrospective study analyzing cases from the NIH/NIAID supported TB Portals database, a large, trans-national, multi-site cohort of primarily drug-resistant tuberculosis patients. We analyzed patient records with sputum microscopy readings, radiologist annotated CXR, and treatment outcome including a matching step on important covariates of age, gender, HIV status, case definition, Body Mass Index (BMI), smoking, drug use, and Timika Score across resistance type for comparison.

Results

2142 patients with tuberculosis infection (374 with poor outcome and 1768 with good treatment outcome) were retrospectively reviewed. Bayesian ANOVA demonstrates radiologist observations did not show greater predictive ability for baseline infectiousness (0.77 and 0.74 probability in DS and MDR respectively); however, the observations provided superior prediction of treatment outcome (0.84 and 0.63 probability in DS and MDR respectively). Estimated lung abnormal area and cavity were identified as important predictors underlying the Timika Score's performance.

Conclusions

Timika Score simplifies the usage of baseline CXR for prediction of early infectiousness of the case and shows comparable performance to using detailed, standardized radiologist observations. The score's utility diminishes for treatment outcome prediction and is exceeded by the usage of the detailed observations although prediction performance on treatment outcome decreases especially in MDR TB cases.

Active pulmonary tuberculosis: something old, something new, something borrowed, something blue

Tuberculosis remains a major global health issue affecting all countries and age groups. Radiology plays a crucial role in the diagnosis and management of pulmonary tuberculosis (PTB). This review aims to improve understanding and diagnostic value of imaging in PTB. We present the old, well-established findings ranging from primary TB to the common appearances of post-primary TB, including dissemination with tree-in-bud nodularity, haematogenous dissemination with miliary nodules and lymphatic dissemination. We discuss new concepts in active PTB with special focus on imaging findings in immunocompromised individuals. We illustrate PTB appearances borrowed from other diseases in which the signs were initially described: the reversed halo sign, the galaxy sign and the cluster sign. There are several radiological signs that have been shown to correlate with positive or negative sputum smears, and radiologists should be aware of these signs as they play an important role in guiding the need for isolation and empirical anti-tuberculous therapy.

Clinico-radiological and bronchoscopic predictors of microbiological yield in sputum negative tuberculosis in Pakistan

To determine association of clinico-radiological factors and radiological activity with diagnostic yield in sputum-smear negative tuberculosis (TB). Prospective observational study in Military Hospital Rawalpindi from July to December 2018. Adult patients having no contraindications to bronchoscopy were included. HIV positive patients and those on anti-tuberculosis therapy for more than one week were excluded. High-Resolution Computed tomography (HRCT) findings were classified based on active and inactive tuberculosis features. Washings were sent for Acid-Fast Bacillus (AFB) smear, GeneXpert assay and cultures. Out of 215 patients, 42.3% (91) were diagnosed with microbiological or histological evidence of TB. On univariate analysis, cavitation (p-value <0.001), soft-tissue nodules (p-value 0.04), and endobronchial mucosal changes (p-value 0.02) were associated with culture positivity. Presence of cavitation (OR= 4.10; CI= 2.18,7.73; p-value<0.001) was the only independent predictor of microbiological yield. Diagnostic yield was 70%, 50%, 12.5% and 8.6% in patients with definitely active, probably active, indeterminate and inactive tuberculosis HRCT features respectively. Sensitivity, specificity, positive predictive value and negative predictive value of HRCT active TB were 95.38% (95% CI 87.10 -99.04), 48.00 % (95% CI 39.78 -56.30), 44.29% (95% CI 40.31 -48.33), 96.00 % (95%CI 88.70 -98.66) respectively. There was no significant association between age groups, smoking status and gender with diagnosis of tuberculosis in our study. Radiological activity and certain visualized bronchoscopic changes were associated with good diagnostic performance and can be used as predictive factors in diagnosis of active smear negative tuberculosis.

Effectiveness of Chest CT in Children: CT Findings in Relation to the Clinical Question

PURPOSE

 To estimate the effectiveness and efficiency of chest CT in children based on the suspected diagnosis in relation to the number of positive, negative, and inconclusive CT results.

MATERIALS AND METHODS

 In this monocentric retrospective study at a university hospital with a division of pediatric radiology, 2019 chest CT examinations (973 patients; median age: 10.5 years; range: 2 days to 17.9 years) were analyzed with regards to clinical data, including the referring department, primary questions or suspected diagnosis, and CT findings. It was identified if the clinical question was answered, whether the suspected diagnosis was confirmed or ruled out, and if additional findings (clinically significant or minor) were detected.

RESULTS

 The largest clinical subgroup was the hematooncological subgroup (n = 987), with frequent questions for inflammation/pneumonia (66 % in this subgroup). Overall, CT provided conclusive results in 97.6 % of all scans. In 1380 scans (70 %), the suspected diagnosis was confirmed. In 406/2019 cases (20 %), the CT scan was negative also in terms of an additional finding. In 8 of 9 clinical categories, the proportion of positive results was over 50 %. There were predominantly negative results (110/179; 61 %) in pre-stem cell transplant evaluation. In the subgroup of trauma management, 81/144 exams (57 %) showed positive results, including combined injuries (n = 23). 222/396 (56 %) of all additional findings were estimated to be clinically significant.

CONCLUSION

 In a specialized center, the effectiveness of pediatric chest CT was excellent when counting the conclusive results. However, to improve efficiency, the clinical evaluation before imaging appears crucial to prevent unnecessary CT examinations.

KEY POINTS

  · Pediatric chest CT in specialized centers has a high diagnostic value.. · CT identifies relevant changes besides the working hypothesis in clinically complex situations.. · Pre-CT clinical evaluation is crucial, especially in the context of suspected pneumonia..

CITATION FORMAT

· Esser M, Tsiflikas I, Kraus MS et al. Effectiveness of Chest CT in Children: CT Findings in Relation to the Clinical Question. Fortschr Röntgenstr 2021; DOI: 10.1055/a-1586-3023.

The Blood Neutrophil Count After 1 Month of Treatment Predicts the Radiologic Severity of Lung Disease at Treatment End

BACKGROUND

Lung disease after tuberculous confers significant morbidity. However, the determinants of persistent lung damage in TB are not well established. We investigated associations between TB-associated radiologic changes and sociodemographic factors, surrogates of bacillary burden, and blood inflammatory markers at initiation of therapy and after 1 month.

RESEARCH QUESTION

What are the predictors of radiologic severity at the end of TB treatment for TB?

STUDY DESIGN AND METHODS

We collected data from patients treated for drug-sensitive pulmonary TB at our center over a 5.5-year period. We recorded age, sex, ethnicity, smoking status, symptom duration, sputum smear grade, time to culture positivity, and blood results (C-reactive protein and neutrophil count) at baseline and after 1 month of treatment. Chest radiographs obtained at baseline, 2 months, and end of treatment were assessed independently by two radiologists and scored using a validated system. Relationships between predictor variables and radiologic outcomes were assessed using linear or binary logistic regression.

RESULTS

We assessed 154 individuals with a mean age of 37 years, 63% of whom were men. In a multivariate analysis, baseline radiologic severity correlated with sputum smear grade (P = 0.003) and neutrophil count (P < 0.001). At end of treatment, only the 1-month neutrophil count was associated significantly with overall radiologic severity in the multivariate analysis (r = 0.34; P = 0.003) and remained significant after controlling for baseline radiologic scores. The 1-month neutrophil count also was the only independent correlate of volume loss and pleural thickening at the end of treatment and was significantly higher in patients with persistent cavitation or effusion vs those without.

INTERPRETATION

Persistent neutrophilic inflammation after 1 month of TB therapy is associated with poor radiologic outcome, suggesting a target for interventions to minimize lung disease after tuberculous.

Clinical and CT characteristics of Xpert MTB/RIF-negative pulmonary tuberculosis

Purpose

To determine the diagnostic accuracy of the Xpert MTB/RIF assay in patients with smear-negative pulmonary tuberculosis (TB) and to assess clinical and CT characteristics of Xpert-negative pulmonary TB.

Material and methods

We retrospectively reviewed the records of 1,400 patients with suspected pulmonary TB for whom the sputum Xpert MTB/RIF assay was performed between September 1, 2014 and February 28, 2020. Clinical and CT characteristics of smear-negative pulmonary TB patients with negative Xpert MTB/RIF results were compared with positive results.

Results

Of 1,400 patients, 365 (26.1%) were diagnosed with pulmonary TB and 190 of 365 patients (52.1%) were negative for sputum acid-fast bacilli. The diagnosis of pulmonary TB was based on a positive culture, positive Xpert MTB/RIF or the clinical diagnoses of patients treated with an anti-TB medication. The sensitivity, specificity, positive predictive and negative predictive values of sputum Xpert MTB/RIF for smear-negative pulmonary TB were 41.1%, 100%, 100%, and 90.1%, respectively. Finally, 172 patients with smear-negative pulmonary TB who underwent chest CT within 2 weeks of diagnosis were included to compare Xpert-positive (n = 66) and Xpert- negative (n = 106) groups. Patients with sputum Xpert-negative TB showed lower positive rates for sputum culture (33.0% vs. 81.8%, p<0.001) and bronchoalveolar lavage culture (53.3% vs. 84.6%, p = 0.042) than in Xpert-positive TB. Time to start TB medication was longer in patients with Xpert-negative TB than in Xpert-positive TB (11.3±16.4 days vs. 5.0±8.7 days, p = 0.001). On chest CT, sputum Xpert-negative TB showed significantly lower frequency of consolidation (21.7% vs. 39.4%, p = 0.012), cavitation (23.6% vs. 37.9%, p = 0.045), more frequent peripheral location (50.9% vs. 21.2 p = 0.001) with lower area of involvement (4.3±4.3 vs. 7.6±6.4, p<0.001). Multivariate analysis revealed peripheral location (odds ratios, 2.565; 95% confidence interval: 1.157–5.687; p = 0.020) and higher total extent of the involved lobe (odds ratios, 0.928; 95% confidence interval: 0.865–0.995; p = 0.037) were significant factors associated with Xpert MTB/RIF-negative TB. Regardless of Xpert positivity, more than 80% of all cases were diagnosed of TB on chest CT by radiologists.

Conclusion

The detection rate of sputum Xpert MTB/RIF assay was relatively low for smear negative pulmonary TB. Chest CT image interpretation may play an important role in early diagnosis and treatment of Xpert MTB/RIF-negative pulmonary TB.

Associated factors of co-existent pulmonary tuberculosis and lung cancer: A case-control study

BACKGROUND

Although the incidence of co-existent pulmonary tuberculosis (PTB) and lung cancer in China is increasing, risk factors related to its development are still poorly understood. We aimed to investigate which clinical factors were associated with the odds of co-existent PTB and lung cancer (PTB-lung cancer) cases in a case-control study.

METHOD

A total of 125 PTB-lung cancer patients were enrolled by Beijing Chest Hospital as the case group between January 2012 and December 2016. Age- and sex-matched PTB-only (N = 125) and lung cancer-only (N = 125) patients were selected as the control groups. Data were collected from the medical records and computed tomography (CT) reports. The case group was further categorized into three sub-groups according to the diagnosis intervals between previous PTB and lung cancer (<1 year, 1-10 years, and > 10 years).

RESULT

Compared with both controls of PTB-only and lung cancer-only patients, the PTB-lung cancer case group had significantly higher proportions of patients with irritant cough, expectoration, hemoptysis, fever and CT features of irregular mass and pleural thickening. For PTB patients, fibrous calcification (OR, 2.193; 95%CI, 1.168-4.117) was associated with higher odds of lung cancer (P-value < .05).

CONCLUSION

Distinct clinical symptoms and CT tests may help with the early diagnosis of PTB-lung cancer cases. PTB patients with fibrous calcification may have a higher risk of lung cancer. Further multicenter prospective studies are required to validate our findings.

Determining the optimal puncture site of CT-guided transthoracic needle aspiration biopsy for the diagnosis of tuberculosis

Background

The purpose of this study was to determine the optimal puncture site of computed tomography (CT)-guided transthoracic needle aspiration biopsy for the diagnosis of tuberculosis (TB) by the comparison of clinical and radiological characteristics of TB patients stratified to different histopathological results.

Methods

We retrospectively analysed the data of clinically diagnosed TB patients with negative laboratory results between July 2016 and June 2018. Biopsy specimens were obtained from patients for Ziehl-Neelsen (Z-N) staining and TB-DNA.

Results

For the 356 TB patients, the positive rate of TB-DNA was 70.9%, which was significantly higher than that of Z-N staining (46.4%, P<0.001). The positive rate of lesions from upper lobe (76.4%, 155/203) was significantly higher than that from lower lobe (63.1%, 89/141, P=0.008). The mean of ΔCT density for positive histologic group (12.84±6.81 HU) was lower than that for negative histologic group (28.32±9.82 HU, P<0.001). ROC curve analysis revealed that a density-based cut-off value of 20.5 HU should be set as the cut-off values for determining the optimal puncture site.

Conclusions

Our data demonstrates that the molecular diagnostics has superiority over Z-N staining for detecting MTB from lung aspirates. The lung biopsies from upper lobe were more likely to yield positive histologic results than those from lower lobe. In addition, the enhancement of 20.5 HU by CT scans should be set as the cut-off values for determining the optimal puncture site that would facilitate an efficient diagnosis of pulmonary TB.

A systematic review of clinical outcomes on the WHO Category II retreatment regimen for tuberculosis

OBJECTIVE

To assess the clinical outcomes of patients prescribed the World Health Organization (WHO) Category II retreatment regimen for tuberculosis (TB).

DESIGN

A systematic review of the literature was performed by searching Medscape, Embase and Scopus databases for cohort studies and clinical trials reporting outcomes in adult patients on the Category II retreatment regimen.

RESULTS

The proportion of patients successfully completing the retreatment regimen varied from 27% to 92% in the 39 studies included in this review. In only 2/39 (5%) studies was the treatment success rate > 85%. There are very few data concerning outcomes in patients categorised as 'other', and outcomes in this subgroup are variable. Of the five studies reporting disaggregated outcomes in human immunodeficiency virus (HIV) positive people, four demonstrated worse outcomes than in HIV-negative people on the retreatment regimen. Only four studies reported disaggregated outcomes in patients with isoniazid (INH) resistance, and treatment success rates varied from 11% to 78%.

CONCLUSION

Clinical outcomes on the Category II retreatment regimen are poor across various populations. Improvements in management should consider the holistic treatment of comorbidity and comprehensive approaches to drug resistance in patients with recurrent TB, including a standardised approach for the management of INH resistance in patients who develop recurrent TB in settings without reliable access to comprehensive drug susceptibility testing.

How radiology can help pulmonary tuberculosis diagnosis: analysis of 49 patients

PURPOSE

To identify the most frequent radiological findings of pulmonary tuberculosis using CT of the chest, to determine those with the highest degree of correlation, and, if possible, to identify the most suggestive radiological findings for acid-fast bacilli (AFB) positive disease.

MATERIALS AND METHODS

The radiological and clinical data of 49 patients submitted to CT during diagnosis were retrospectively analysed. The association between findings was assessed using Fisher's exact test, while correlation at CT scan was evaluated with the Spearman analysis.

RESULTS

Bronchiectasis/bronchioloectasis (89.8%), nodule(s) (81.6%), tree-in-bud (TIB), and consolidation (79.6% each) figured among the most common parenchymal findings. Lymphadenopathy (26.5%) was the most common nodal finding. TIB and cavity showed the highest correlation (r = 0.577), followed by TIB and bronchi(olo)ectasis (r = 0.498), TIB and consolidation (r = 0.497), nodule(s), and ground glass opacity (r = 0.488). High correlation was found in only the seven most frequent parenchymal findings. Consolidation, TIB, and cavity were useful to predict the AFB stain positivity.

CONCLUSIONS

Our series confirms the extreme heterogeneity of pulmonary tuberculosis. It also proves there are couple of findings which can drive us to the right diagnosis. While a triad of findings predicts AFB positivity, we have not found any predictive sign of AFB negativity; consequently, all patients with suspected imaging and clinical findings for TB should be isolated.

Tuberculosis cutis orificialis with underlying pulmonary tuberculosis in an immunocompetent man

Tuberculosis cutis orificialis (TCO) is a rare form of tuberculosis more often secondary to pulmonary tuberculosis. TCO has varied differential diagnoses and thus results in delayed diagnosis and treatment leading to serious consequences. The diagnosis of TCO is confirmed by biopsy and nucleic acid amplification tests in majority of cases. We report a case of TCO with underlying pulmonary tuberculosis in a 50-year-old male, who presented with a painful nonhealing ulcer of the right buccal mucosa. Biopsy and real-time polymerase chain reaction helped in confirming the diagnosis. The patient was treated with antitubercular therapy.

Chronic Airspace Diseases

Airspace disease can be acute or chronic and commonly present as consolidation or ground-glass opacity on chest imaging. Consolidation or ground-glass opacity occurs when alveolar air is replaced by fluid, pus, blood, cells, or other material. Airspace disease is considered chronic when it persists beyond 4-6 weeks after treatment. These can be secondary to certain infectious, inflammatory, or neoplastic conditions. Computed tomography of the chest is usually performed in this set of patients to identify characteristic imaging findings. Familiarity with the differential diagnosis and characteristic imaging findings for chronic airspace disease is very important for guiding patient's management in a timely fashion.

[Pulmonary tuberculosis: Radiological evolution of broncho-pulmonary lesions at the end of treatment]

OBJECTIVES

To describe the residual broncho-pulmonary lesions and evaluate the role of CT scanning at the end of treatment of pulmonary tuberculosis.

MATERIALS AND METHODS

Analysis of the initial and end of treatment CT scans of 56 patients with pulmonary tuberculosis according to a reading grid including parenchymatous and airways lesions. The CT data at the end of treatment were analysed in relation to the clinical and microbiological data, and the original CT scan.

RESULTS

Active lesions (thick walled cavities and/or centrilobular micronodules) persisted in 24 patients (43%) after a mean treatment period of 7 months. The persistence of these signs of activity was correlated with the initial presence of a cavitary syndrome (p=0.027), with predominant sub-segmentary bronchial involvement, with extensive micronodular spread (p=0.024) and with bronchiectasis (p=0.04). These residual lesions were not associated with an increased risk of relapse.

CONCLUSION

The persistence of signs of activity on the CT scan at the end of treatment of tuberculosis do not necessarily correspond to an absence of cure but to a radiological delay. This imaging is nevertheless useful to make an assessment of any subsequent changes in the bronchial tree and to estimate the risk of later complications.

Utility of GeneXpert in analysis of bronchoalveolar lavage samples from patients with suspected tuberculosis in an intermediate-burden setting

OBJECTIVES

To explore the clinical role of GeneXpert in managing pulmonary tuberculosis (TB) in an intermediate burden city.

METHODS

Sputum acid-fast-bacilli (AFB) smear negative patients underwent bronchoscopy for bronchial alveolar lavage (BAL). Fluids collected were examined for AFB smear, TB culture, TB polymerase chain reaction (PCR) (Cobas Taqman) and for GeneXpert.

RESULTS

From October 2015 to February 2017, 227 BAL samples were collected. Cough and haemoptysis were the presenting symptoms in 70.0% and 37.4%, respectively. Apical shadows on chest X-rays (CXR) and apical cavitations on computed tomography (CT) were commoner in GeneXpert positive cases (p = 0.01 and 0.02, respectively). Sensitivity and specificity of GeneXpert for TB diagnosis was 80% and 98% respectively. Positive and negative predictive value of the test was 92.3 and 95.1%, respectively. There were 9 false negative GeneXpert samples (8 were Cobas Taqman TB PCR negative): 6 were diagnosed by BAL culture, 2 by biopsy and one by Cobas Taqman TB PCR. There were 3 false positive cases with negative culture; 2 were put on empirical treatment with favourable clinical responses, while one defaulted follow-p.

CONCLUSION

GeneXpert in BAL samples has high sensitivity and specificity. It enabled timely initiation of anti-TB treatment in clinical suspicious cases.

Massive Hemoptysis with a Fungus Ball-like Shadow in an Old Tuberculosis Cavity That Was Shown to Be a Clot by Bronchoscopy

Development of aspergilloma is common in cases with a fungus ball-like shadow in cavities due to old tuberculosis. Some reports have shown that blood clots tend to appear as a fungus ball-like shadow. A 71-year-old man with a history of pulmonary tuberculosis presented with a fungus ball-like shadow in an old cavity and hemoptysis. There was no evidence of aspergillus infection on various examinations. We confirmed a blood clot and aneurysm of an artery under direct vision by bronchoscopy. A lateral thoracic artery aneurysm was detected by angiography. Transcatheter arterial embolization was performed. After treatment, the artery aneurysm disappeared.

A Systematic Review of the Prevalence and Pattern of Imaging Defined Post-TB Lung Disease

Background

Tuberculosis is an important risk factor for chronic respiratory disease in resource poor settings. The persistence of abnormal spirometry and symptoms after treatment are well described, but the structural abnormalities underlying these changes remain poorly defined, limiting our ability to phenotype post-TB lung disease in to meaningful categories for clinical management, prognostication, and ongoing research. The relationship between post-TB lung damage and patient-centred outcomes including functional impairment, respiratory symptoms, and health related quality of life also remains unclear.

Methods

We performed a systematic literature review to determine the prevalence and pattern of imaging-defined lung pathology in adults after medical treatment for pleural, miliary, or pulmonary TB disease. Data were collected on study characteristics, and the modality, timing, and findings of thoracic imaging. The proportion of studies relating imaging findings to spirometry results and patient morbidity was recorded. Study quality was assessed using a modified Newcastle-Ottowa score. (Prospero Registration number CRD42015027958)

Results

We identified 37 eligible studies. The principle features seen on CXR were cavitation (8.3–83.7%), bronchiectasis (4.3–11.2%), and fibrosis (25.0–70.4%), but prevalence was highly variable. CT imaging identified a wider range of residual abnormalities than CXR, including nodules (25.0–55.8%), consolidation (3.7–19.2%), and emphysema (15.0–45.0%). The prevalence of cavitation was generally lower (7.4–34.6%) and bronchiectasis higher (35.0–86.0%) on CT vs. CXR imaging. A paucity of prospective data, and data from HIV-infected adults and sub-Saharan Africa (sSA) was noted. Few studies related structural damage to physiological impairment, respiratory symptoms, or patient morbidity.

Conclusions

Post-TB structural lung pathology is common. Prospective data are required to determine the evolution of this lung damage and its associated morbidity over time. Further data are required from HIV-infected groups and those living in sSA.

Associations between systemic inflammation, mycobacterial loads in sputum and radiological improvement after treatment initiation in pulmonary TB patients from Brazil: a prospective cohort study

Background

Mycobacterium tuberculosis infection is known to cause inflammation and lung tissue damage in high-risk populations. Nevertheless, direct associations between mycobacterial loads, systemic inflammation and pulmonary lesions upon treatment initiation have not been fully characterized. In the present exploratory study, we prospectively depict the immune profile, microbial clearance and evolution of radiographic lesions in a pulmonary tuberculosis (PTB) patient cohort before and 60 days after anti-tuberculous treatment (ATT) initiation.

Methods

Circulating levels of cytokines (IL-2, IL-4, IL-6, IL-10, IFN-γ, TNF-α) and C-reactive protein (CRP), as well as values of erythrocyte sedimentation rate (ESR) were measured in cryopreserved serum samples obtained from 73 PTB patients at pre-ATT and day 60 of treatment. Changes of the immune profile over time were compared with mycobacterial loads in sputum and culture conversion at day 60 of ATT. Additional analyses tested associations between improvement of chest radiographic lesions at day 60 and pre-treatment status of inflammation and mycobacterial loads.

Results

Within the inflammatory parameters evaluated, values of CRP, IL-2, IL-4, TNF-α and ESR significantly decreased upon treatment initiation. On the converse, IL-10 levels substantially increased at day 60 of ATT, whereas concentrations of IL-6 and IFN-γ remained unchanged. Multidimensional analyses revealed that ESR, IL-2, IL-4 and CRP were the parameters with the highest power to discriminate individuals before and after treatment initiation. We further demonstrated that higher bacterial loads in sputum at pre-ATT were associated with increased systemic inflammation and higher risk for positive M. tuberculosis sputum cultures at day 60 of treatment. Furthermore, we found that pre-ATT mycobacterial loads in sputum and systemic inflammation synergistically associated with the status of radiographic lesions during treatment (Relative risk for chest X-ray improvement: 10.0, 95 % confidence interval: 2.4–40.0, P = 0.002).

Conclusions

M. tuberculosis loads in sputum are directly associated to the status of systemic inflammation and potentially impact the immune profile, culture conversion and evolution of lung lesions upon ATT initiation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1736-3) contains supplementary material, which is available to authorized users.

PET/CT imaging correlates with treatment outcome in patients with multidrug-resistant tuberculosis

Definitive clinical trials of new chemotherapies for treating tuberculosis (TB) require following subjects until at least 6 months after treatment discontinuation to assess for durable cure, making these trials expensive and lengthy. Surrogate endpoints relating to treatment failure and relapse are currently limited to sputum microbiology, which has limited sensitivity and specificity. We prospectively assessed radiographic changes using 2-deoxy-2-[(18)F]-fluoro-D-glucose (FDG) positron emission tomography/computed tomography (PET/CT) at 2 and 6 months (CT only) in a cohort of subjects with multidrug-resistant TB, who were treated with second-line TB therapy for 2 years and then followed for an additional 6 months. CT scans were read semiquantitatively by radiologists and were computationally evaluated using custom software to provide volumetric assessment of TB-associated abnormalities. CT scans at 6 months (but not 2 months) assessed by radiologist readers were predictive of outcomes, and changes in computed abnormal volumes were predictive of drug response at both time points. Quantitative changes in FDG uptake 2 months after starting treatment were associated with long-term outcomes. In this cohort, some radiologic markers were more sensitive than conventional sputum microbiology in distinguishing successful from unsuccessful treatment. These results support the potential of imaging scans as possible surrogate endpoints in clinical trials of new TB drug regimens. Larger cohorts confirming these results are needed.

Treatment of Drug Susceptible Pulmonary Tuberculosis

Tuberculosis (TB) remains a major global health problem, and the incidence of TB cases has not significantly decreased over the past decade in Korea. The standard short course regimen is highly effective against TB, but requires multiple TB-specific drugs and a long treatment duration. Recent studies using late-generation fluoroquinolones and/or high-dose rifapentine-containing regimens to shorten the duration of TB treatment showed negative results. Extending the treatment duration may be considered in patients with cavitation on the initial chest radiograph and positivity in sputum culture at 2 months of treatment for preventing TB relapse. Current evidence does not support the use of fixed-dose combinations compared to separate drugs for the purpose of improving treatment outcomes. All patients receiving TB treatment should be monitored regularly for response to therapy, facilitation of treatment completion, and management of adverse drug reactions. Mild adverse effects can be managed with symptomatic therapy and changing the timing of the drug administration, but severe adverse effects require a discontinuation of the offending drugs.

Diagnosis of pulmonary tuberculosis: recent advances and diagnostic algorithms

Pulmonary tuberculosis (TB) persists as a great public health problem in Korea. Increases in the overall age of the population and the rise of drug-resistant TB have reinforced the need for rapid diagnostic improvements and new modalities to detect TB and drug-resistant TB, as well as to improve TB control. Standard guidelines and recent advances for diagnosing pulmonary TB are summarized in this article. An early and accurate diagnosis of pulmonary TB should be established using chest X-ray, sputum microscopy, culture in both liquid and solid media, and nucleic acid amplification. Chest computed tomography, histopathological examination of biopsy samples, and new molecular diagnostic tests can be used for earlier and improved diagnoses, especially in patients with smear-negative pulmonary TB or clinically-diagnosed TB and drug-resistant TB.

Clinicoradiologic evidence of pulmonary lymphatic spread in adult patients with tuberculosis

OBJECTIVE

The purpose of this study is to evaluate the prevalence and clinicoradiologic characteristics of pulmonary tuberculosis with lymphatic involvement.

MATERIALS AND METHODS

A total of 126 adults with active tuberculosis who underwent CT were enrolled. A retrospective investigation of CT images focused on the presence of perilymphatic micronodules, as well as other CT features of active tuberculosis. We selected two groups of patients with micronodules according to distribution (perilymphatic vs centrilobular). We compared clinical and CT findings between the two groups.

RESULTS

Fifteen patients were excluded because of coexisting pulmonary disease. Among 111 patients, the prevalence of perilymphatic micronodules, galaxy or cluster signs, and interlobular septal thickening was 64 (58%), 18 (16%), and 30 (27%), respectively. Of 106 patients with micronodules, 37 and 40 were classified into the perilymphatic and centrilobular groups, respectively. Compared with the centrilobular group, the perilymphatic group had statistically significantly lower frequencies of positive acid-fast bacilli smears (32% vs 70%), consolidation (70% vs 98%), and cavitation (30% vs 60%). However, frequencies of interlobular septal thickening (41% vs 18%), galaxy or cluster signs (30% vs 0%), and pleural effusion (43% vs 20%) were statistically significantly higher in the perilymphatic group.

CONCLUSION

CT findings representing pulmonary perilymphatic involvement are relatively common in adults with tuberculosis. These findings may represent lymphatic spread of tuberculosis and provide an explanation for the unusual CT features of pulmonary tuberculosis mimicking sarcoidosis and the low detection of Mycobacterium tuberculosis in patients with micronodules.

Computer-aided detection and quantification of cavitary tuberculosis from CT scans

PURPOSE

To present a computer-aided detection tool for identifying, quantifying, and evaluating tuberculosis (TB) cavities in the infected lungs from computed tomography (CT) scans.

METHODS

The authors' proposed method is based on a novel shape-based automated detection algorithm on CT scans followed by a fuzzy connectedness (FC) delineation procedure. In order to assess interaction between cavities and airways, the authors first roughly identified air-filled structures (airway, cavities, esophagus, etc.) by thresholding over Hounsfield unit of CT image. Then, airway and cavity structure detection was conducted within the support vector machine classification algorithm. Once airway and cavities were detected automatically, the authors extracted airway tree using a hybrid multiscale approach based on novel affinity relations within the FC framework and segmented cavities using intensity-based FC algorithm. At final step, the authors refined airway structures within the local regions of FC with finer control. Cavity segmentation results were compared to the reference truths provided by expert radiologists and cavity formation was tracked longitudinally from serial CT scans through shape and volume information automatically determined through the authors' proposed system. Morphological evolution of the cavitary TB were analyzed accordingly with this process. Finally, the authors computed the minimum distance between cavity surface and nearby airway structures by using the linear time distance transform algorithm to explore potential role of airways in cavity formation and morphological evolution.

RESULTS

The proposed methodology was qualitatively and quantitatively evaluated on pulmonary CT images of rabbits experimentally infected with TB, and multiple markers such as cavity volume, cavity surface area, minimum distance from cavity surface to the nearest bronchial-tree, and longitudinal change of these markers (namely, morphological evolution of cavities) were determined precisely. While accuracy of the authors' cavity detection algorithm was 94.61%, airway detection part of the proposed methodology showed even higher performance by 99.8%. Dice similarity coefficients for cavitary segmentation experiments were found to be approximately 99.0% with respect to the reference truths provided by two expert radiologists (blinded to their evaluations). Moreover, the authors noted that volume derived from the authors' segmentation method was highly correlated with those provided by the expert radiologists (R(2) = 0.99757 and R(2) = 0.99496, p < 0.001, with respect to the observer 1 and observer 2) with an interobserver agreement of 98%. The authors quantitatively confirmed that cavity formation was positioned by the nearby bronchial-tree after exploring the respective spatial positions based on the minimum distance measurement. In terms of efficiency, the core algorithms take less than 2 min on a linux machine with 3.47 GHz CPU and 24 GB memory.

CONCLUSION

The authors presented a fully automatic method for cavitary TB detection, quantification, and evaluation. The performance of every step of the algorithm was qualitatively and quantitatively assessed. With the proposed method, airways and cavities were automatically detected and subsequently delineated in high accuracy with heightened efficiency. Furthermore, not only morphological information of cavities were obtained through the authors' proposed framework, but their spatial relation to airways, and longitudinal analysis was also provided to get further insight on cavity formation in tuberculosis disease. To the authors' best of knowledge, this is the first study in computerized analysis of cavitary tuberculosis from CT scans.

High resolution computed tomography findings in smear-negative pulmonary tuberculosis patients according to their culture status

OBJECTIVE

The aim of this study was to assess the clinical features and high resolution computed tomography (HRCT) findings in smear-negative pulmonary tuberculosis (PTB) and to evaluate the correlation between these parameters and the culture results.

METHODS

We retrospectively studied 78 active smear-negative PTB patients. They were divided into two groups according to their culture results. The HRCT findings and clinical features at the beginning of the antituberculosis treatment were reviewed.

RESULTS

The mean age was 22.48±3.18 years. Micronodules (87%), large nodules (63%) and centrilobular nodules (62%) were the most common HRCT findings. HRCT findings were observed in the right upper (72%), left upper (56%), right lower (32%), and left lower lobes (29%). Cough (37%) and chest pain (32%) were the most frequent symptoms at presentation.

CONCLUSIONS

There were no significant differences in the HRCT findings and clinical features between the two groups. Thus, in cases of smear-negative and culture-negative PTB, the patient with compatible clinical and radiological features should be considered for tuberculosis treatment.

[Chest computed tomography in children: indications, efficiency and effective dose]

INTRODUCTION

New multidetector row computed tomography (CT) has made the imaging of younger children more feasible and extending CT indications to a wide range of pediatric respiratory diseases in the last few years. However, CT is a source of radiation exposure. The aim of this study was to evaluate the main indications and the contribution of chest CT in pediatric pulmonology as well as induced radiation.

METHODS

This was an observational, prospective study. Children whose chest CTs were analyzed during multidisciplinary meetings (radiologist, pulmonary pediatrician) were included from November 2009 to April 2010. We collected demographic data, CT results, contribution of CT to diagnosis and management, and radiation doses (dose-length product [DLP] and effective dose). Radiation doses were compared according to the CT scans (Lille University Hospital with 128-slice dual-source CT or Lille University Hospital single-source 64-slice CT, or CT performed outside the university hospital).

RESULTS

One hundred thirty-five patients were included. The mean age was 6.4 years old. The main indications were analysis of bronchial disease (44%), infectious disease (16%), interstitial disease (14%), or a malformation (9%). The aim of CT was diagnosis (61%) or follow-up of previous lung diseases (39%). Diagnosis chest-CT directly contributed to diagnosis in 48% of cases and to treatment in 24%. Follow-up CT contributed to diagnosis in 38% and treatment in 19% of cases. DLP and effective doses were significantly lower for CT performed in the university hospital, especially with the 128-slice CT compared to the others (P<0.001). The effective doses were: 128-slice CT, 0.61 mSv ± 0.32; 64-slice CT, 1.24 mSv ± 0.97; outside university hospital, 2.56 mSv ± 1.98.

CONCLUSION

This study confirms the role played by chest CT in children, which contributes to diagnosis and management of lung diseases. The main concern of CT application, especially in children, is the radiation burden. Children are more susceptible to the effects of radiation than adults and have a longer life expectancy to develop complications. Both radiologists and pediatricians should be aware of a potential risk and have to conjugate their efforts in reducing this risk. The wide range of radiation doses in this study for the same CT procedures underlines the extensive efforts still needed to limit radiation exposure in children.

Clinical characteristics and treatment outcomes of tuberculosis in the elderly: a case control study

Background

The purpose of this study was to evaluate the differences in clinical characteristics and treatment outcomes between older and younger tuberculosis (TB) patients in Korea.

Methods

We retrospectively analyzed the medical records of 271 younger (20–64 years old at diagnosis) and 199 older (≥65 years) TB patients who had been newly diagnosed and treated at Chonnam National University Hospital from May 2008 to August 2010.

Results

Dyspnea and comorbid medical conditions were more frequent and positive TB culture rates were higher in older TB patients. In chest computed tomography (CT) scans of pulmonary TB patients, older patients were less likely to have micronodules (<7 mm in diameter), nodules (<30 mm in diameter), masses (>30 mm in diameter), and cavities compared with younger patients, but were more likely to have consolidations. Incidence of adverse drug reactions did not differ between the two groups, except for severe gastrointestinal disorders. There were no significant differences in favorable treatment outcomes between younger and older TB patients (97% vs. 94%, respectively; p = 0.251).

Conclusions

Older TB patients had more frequent dyspnea and less frequent active TB findings on chest CT. Treatment success and adverse drug reaction rates were similar in older and younger TB patients.

Chronic destructive pulmonary tuberculosis: assessment of disease activity by computed tomography

BACKGROUND

Determination of disease activity of chronic destructive pulmonary tuberculosis (TB) on imaging studies can be difficult because several imaging findings due to disease chronicity such as a residual cavity can be misinterpreted as an active disease.

PURPOSE

To evaluate computed tomography (CT) findings to predict active disease in patients with chronic destructive pulmonary TB.

MATERIAL AND METHODS

CT findings of 36 patients with chronic active destructive pulmonary TB and 78 patients with chronic inactive destructive pulmonary TB were reviewed and their patterns of lung lesions were compared. Statistical comparisons were performed using chi-square and Student's T tests for univariate analyses, and a stepwise logistic regression method was used for multivariate analysis.

RESULTS

Based on univariate analyses, cavitary destruction (P = 0.015), non-branching centrilobular nodules (P < 0.001), tree-in-bud pattern (P < 0.001), airspace nodules (P < 0.001), and cavities in other lobes (P = 0.001) were more frequently seen in chronic active destructive pulmonary TB. A stepwise logistic regression analysis demonstrated that tree-in-bud pattern (odds ratio, 52.3; 95% confidence interval, 6.2-437.2; P < 0.001) were significant CT findings associated with active disease.

CONCLUSION

Tree-in-bud pattern were the most characteristic CT findings to predict active disease in patients with chronic destructive pulmonary TB.

Multifunctional CD4 T cell responses in patients with active tuberculosis

The roles of multifunctional CD4 T cells in human tuberculosis are not well defined. In this study, we found that patients with tuberculosis had decreased PMA/ionomycin stimulated multifunctional CD4 T cells, and increased Mycobacterium tuberculosis antigen-specific multifunctional CD4 T cells, when compared to individuals with latent tuberculosis infection and healthy controls. PMA/ionomycin stimulated IFN-γ⁺IL-2⁺TNF-α⁺ CD4 T cell responses were decreased in patients with smear-positive tuberculosis compared to those with smear-negative tuberculosis. The percentage of IFN-γ⁺IL-2⁺TNF-α⁺ CD4 T cells in smear positive tuberculosis patients negatively correlated with the grade of sputum smear Acid-Fast Bacilli and high-resolution computed tomography score. Therefore, our findings argue against the notion that Mycobacterium tuberculosis antigen-specific multifunctional Th1 responses in peripheral blood can serve as correlates of protective immunity against tuberculosis; they suggest that the decrease in PMA/ionomycin stimulated IFN-γ⁺IL-2⁺TNF-α⁺ CD4 T cells may be applied for clinical diagnosis of active tuberculosis.

Global burden of chronic pulmonary aspergillosis as a sequel to pulmonary tuberculosis

OBJECTIVE

To estimate the global burden of chronic pulmonary aspergillosis (CPA) after pulmonary tuberculosis (PTB), specifically in cases with pulmonary cavitation.

METHODS

PTB rates were obtained from the World Health Organization and a scoping review of the literature was conducted to identify studies on residual pulmonary cavitation after PTB and estimate the global incidence of CPA after PTB. Having established that from 21% (United States of America) to 35% (Taiwan, China) of PTB patients developed pulmonary cavities and that about 22% of these patients developed CPA, the authors applied annual attrition rates of 10%, 15% and 25% to estimate the period prevalence range for CPA over five years. Analysis was based on a deterministic model.

FINDINGS

In 2007, 7.7 million cases of PTB occurred globally, and of them, an estimated 372,000 developed CPA: from 11,400 in Europe to 145,372 in South-East Asia. The global five-year period prevalence was 1,174,000, 852,000 and 1,372,000 cases at 15%, 25% and 10% annual attrition rates, respectively. The prevalence rate ranged from < 1 case per 100,000 population in large western European countries and the United States of America to 42.9 per 100,000 in both the Democratic Republic of the Congo and Nigeria. China and India had intermediate five-year period prevalence rates of 16.2 and 23.1 per 100,000, respectively.

CONCLUSION

The global burden of CPA as a sequel to PTB is substantial and warrants further investigation. CPA could account for some cases of smear-negative PTB. Since CPA responds to long-term antifungal therapy, improved case detection should be urgently undertaken.

Pulmonary involvement in pleural tuberculosis: how often does it mean disease activity?

OBJECTIVE

To evaluate in chest X-rays and high-resolution computed tomographies of patients with pleural tuberculosis, the incidence of parenchymal and mediastinal lung lesions suggestive of active disease.

METHODS

Prospective study (2008-2009) evaluating the radiographic and tomographic abnormalities of 88 HIV-negative patients with pleural tuberculosis (unilateral effusion). The images were reviewed by 3 independent specialists, and the observed changes were classified according to previously established criteria: presence or absence of signs suggestive of disease activity, and nonspecific findings.

RESULTS

Abnormal changes were observed in chest X-rays of 22 (25%) patients and in the computed tomography of 55 (63%). Images compatible with active pulmonary tuberculosis were detected by radiography in 9 (10%) patients and by tomography in 38 (43%). Only 4 (4.5%) patients had tomography images suggestive of residual disease.

CONCLUSION

The present study demonstrates that pulmonary involvement is quite common in pleural tuberculosis. This finding is mainly observed in high-resolution computed tomography and has important epidemiological implications, since patients with pleural tuberculosis are significant sources of infection and disease dissemination.

Usefulness of an in-vitro tuberculosis interferon-&#x03B3; release assay (T-SPOT.TB) in the first-line check-up of uveitis patients

OBJECTIVES

The main objective of this 1.5-year prospective study was to evaluate the value of T-SPOT®.TB as compared to the tuberculin skin test (TST) for the first-line assessment of uveitis.

METHODS

A total of 108 consecutive non-immunocompromised patients with acute or chronic uveitis, including 92/108 (85.2%) with previous BCG vaccination, underwent a general examination, a TST, and a T-SPOT.TB test (Oxford Immunotec; Oxford, UK), blood and serological tests, and chest imaging. Concordance between tests was assessed using kappa coefficients. The performance of binary classification tests was evaluated with sensitivity, specificity, and likelihood ratios.

RESULTS

The results of the TST and the T-SPOT.TB test differed significantly (55.5% versus 29.6% positivity, P < 0.001), with a low concordance between the two tests (κ = 0.362, P = 0.001). The sensitivity of the TST was 100% (diagnosis of suspected tuberculous uveitis included a positive TST), but its specificity was only 53.3%. The sensitivity and the specificity of the T-SPOT.TB test were 94.4% and 83.3%, respectively. The positive and negative likelihood ratios of the T-SPOT.TB test were 5.67 and 0.07, respectively.

CONCLUSION

In uveitis patients with frequent previous BCG vaccination, the T-SPOT.TB test is more specific than the TST and therefore allows more accurate selection of patients requiring extensive investigations to rule out TB diagnosis.

Solitary pulmonary nodule in the liver transplant candidate: importance of diagnosis and treatment

Our objectives were to define the incidence and etiology of solitary pulmonary nodules (SPNs) in patients undergoing living donor liver transplantation (LDLT), describe a diagnostic approach to the management of SPNs in LDLT, and define the impact of SPNs on the overall survival of adult LDLT recipients. Nine patients (9/152, 5.9%) were diagnosed with an SPN on the basis of chest radiography findings during the pretransplant survey. All were male. The mean age was 52 years. All the patients had hepatitis B virus-related cirrhosis with hepatocellular carcinoma. All were asymptomatic for the lung lesion. All underwent contrast-enhanced chest computed tomography (CT) to verify the presence and possible etiology of the SPNs. In 3 cases, CT was used to definitely determine that there was no pulmonary nodule; in 2, CT led to a definite diagnosis of pulmonary tuberculosis. In 4, CT led to a definite identification of an SPN but not to an etiological diagnosis. Two patients underwent outright thoracoscopy and biopsy of their SPNs. Biopsy showed cryptococcosis in both patients. One received a therapeutic trial of an antituberculosis treatment, and repeat CT after 1 month showed a regression in the size of the SPN. A diagnosis of tuberculosis was made. One patient had an inconclusive whole body positron emission tomography scan and subsequently underwent thoracoscopy where biopsy showed tuberculosis. A concomitant malignancy, either primary lung cancer or metastasis from the liver tumor, was not identified. All patients were surviving with their original grafts and were lung infection-free. The overall mean posttransplant follow-up was 54 months (range = 33-96 months).