Progressive age-related changes in pulmonary tuberculosis images and the effect of diabetes

Characteristics of atypical pulmonary tuberculosis without typical clinical features diagnosed by pathology

PURPOSE

Some patients with pulmonary tuberculosis (PTB) do not display typical clinical features, leading to delays in diagnosis and treatment.

METHODS

We retrospectively analyzed PTB patients admitted to the Second Affiliated Hospital of Chongqing Medical University between 2017 and 2020. They are divided into pathological group (diagnosed through pathological biopsy) and control group (diagnosed via sputum or lavage fluid). Clinical data of both groups were compared. Based on radiographic features, the pathological group was further divided into the inflammation group, peripheral nodule group, and central occupancy group. We then statistically analyzed the computed tomography (CT) signs, bronchoscopic manifestations and results of pathological biopsy for each subgroup.

RESULTS

The pathological group consisted of 75 patients, while the control group had 338 patients. Multivariate logistic regression analysis showed that the pathological group had more diabetes (OR = 3.266, 95% CI = 1.609-6.630, P = 0.001), lower ESR (OR = 0.984, 95% CI = 0.971-0.998, P = 0.022), and lower CRP (OR = 0.990, 95% CI = 0.980-0.999, P = 0.036). In the three subgroups, the exudative lesions in the inflammation group were mostly located in atypical areas of PTB. The lobulation sign and spiculation sign were frequently observed in the peripheral nodule group. All presented with significant hilar mediastinal lymphadenopathy in the central occupancy group. In the pathological group, bronchoscopic manifestations typically included mucosal edema and bronchial stenosis.

CONCLUSION

Diabetes is an independent risk factor for atypical PTB. Expression of erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) in atypical PTB is low. Radiologically, it is most easily misdiagnosed when presented as peripheral solid nodules or masses, so a biopsy is recommended.

The Complex Relationship Between Tuberculosis and Hyperglycemia

Hyperglycemia and tuberculosis are dual global pandemics. Each has a propulsive and amplifying effect on the other, and, because of this, we must consider hyperglycemia and tuberculosis together. Hyperglycemia is immunosuppressive and increases the risk of tuberculosis by threefold. It also leads to a more advanced presentation of pulmonary tuberculosis, thus increasing the likelihood of being smear positive and having cavitating lesions, and it impacts the duration and outcomes of treatment, with an increased one year mortality seen in patients with tuberculosis and diabetes. Additionally, any degree of hyperglycemia can have an impact on susceptibility to tuberculosis, and this effect is not limited to poorly controlled diabetes. Conversely, tuberculosis itself is associated with hyperglycemia and worsens hyperglycemia in those with diabetes mellitus. The impact of this relationship varies based on the base rates of each disease in different regions of the world. In order to successfully achieve the World Health Organization's goals of tuberculosis eradication and adequate glycemic control, we must improve our understanding, co-management, and screening of hyperglycemia and tuberculosis. This review aims to explore the current research investigating the relationship between tuberculosis and diabetes, including the changes in disease susceptibility, presentation, geographic distribution, and effects on treatment.

Tuberculosis patients with diabetes co-morbidity experience reduced Mycobacterium tuberculosis complex clearance

Objective

This study aimed to investigate the impact of diabetes mellitus (DM) on tuberculosis (TB) treatment response using bacterial clearance as a surrogate marker.

Method

We compared smear microscopy, culture, and tuberculosis molecular bacterial load assay (TB-MBLA) for treatment monitoring. Following that, bacterial clearance was longitudinally monitored among TB-only (TB without DM) and TB-diabetes (TBDM) patients using TB-MBLA.

Results

Ninety-three participants, including 59 TB-only and 34 TBDM patients, were enrolled. TB-only patients exhibited higher upper zone infiltrations (32/35 vs 16/22, p = 0.059) suggesting a trend towards significance, and significantly more cavitation in the same zone (16/18 vs 7/13, p = 0.028). There was a high proportion of Mycobacterium africanum (Maf) among the TBDM cohort (p = 0.0044).At baseline, TB-only patients exhibited a higher average bacterial burden (4.49 logeCFU/mL) compared to the TBDM group (3.91 logeCFU/mL) (p = 0.042). The bacterial load in the TB-only group decreased significantly during treatment but the TBDM group experienced delayed clearance throughout the intensive phase of anti-TB treatment even at day 56 (p = 0.028). The TB-only group demonstrated a shorter median time to TB-MBLA conversion to negative (57 days) compared to the TBDM group (62 days) (p = 0.022).

Conclusion

These findings underscore the urgent call for understanding the interplay between diabetes and TB, emphasizing the need for tailored interventions in optimizing TB care for individuals comorbid with diabetes.

Prior tuberculosis, radiographic lung abnormalities and prevalent diabetes in rural South Africa

BACKGROUND

Growing evidence suggests that chronic inflammation caused by tuberculosis (TB) may increase the incidence of diabetes. However, the relationship between post-TB pulmonary abnormalities and diabetes has not been well characterized.

METHODS

We analyzed data from a cross-sectional study in KwaZulu-Natal, South Africa, of people 15 years and older who underwent chest X-ray and diabetes screening with hemoglobin A1c testing. The analytic sample was restricted to persons with prior TB, defined by either (1) a self-reported history of TB treatment, (2) radiologist-confirmed prior TB on chest radiography, and (3) a negative sputum culture and GeneXpert. Chest X-rays of all participants were evaluated by the study radiologist to determine the presence of TB lung abnormalities. To assess the relationships between our outcome of interest, prevalent diabetes (HBA1c ≥6.5%), and our exposure of interest, chest X-ray abnormalities, we fitted logistic regression models adjusted for potential clinical and demographic confounders. In secondary analyses, we used the computer-aided detection system CAD4TB, which scores X-rays from 10 to 100 for detection of TB disease, as our exposure interest, and repeated analyses with a comparator group that had no history of TB disease.

RESULTS

In the analytic cohort of people with prior TB (n = 3,276), approximately two-thirds (64.9%) were women, and the average age was 50.8 years (SD 17.4). The prevalence of diabetes was 10.9%, and 53.0% of people were living with HIV. In univariate analyses, there was no association between diabetes prevalence and radiologist chest X-ray abnormalities (OR 1.23, 95%CI 0.95-1.58). In multivariate analyses, the presence of pulmonary abnormalities was associated with an 29% reduction in the odds of prevalent diabetes (aOR 0.71, 95%CI 0.53-0.97, p = 0.030). A similar inverse relationship was observed for diabetes with each 10-unit increase in the CAD4TB chest X-ray scores among people with prior TB (aOR 0.92, 95%CI 0.87-0.97; p = 0.002), but this relationship was less pronounced in the no TB comparator group (aOR 0.96, 95%CI 0.94-0.99).

CONCLUSIONS

Among people with prior TB, pulmonary abnormalities on digital chest X-ray are inversely associated with prevalent diabetes. The severity of radiographic post-TB lung disease does not appear to be a determinant of diabetes in this South African population.

A deep learning-based algorithm for pulmonary tuberculosis detection in chest radiography

In tuberculosis (TB), chest radiography (CXR) patterns are highly variable, mimicking pneumonia and many other diseases. This study aims to evaluate the efficacy of Google teachable machine, a deep neural network-based image classification tool, to develop algorithm for predicting TB probability of CXRs. The training dataset included 348 TB CXRs and 3806 normal CXRs for training TB detection. We also collected 1150 abnormal CXRs and 627 normal CXRs for training abnormality detection. For external validation, we collected 250 CXRs from our hospital. We also compared the accuracy of the algorithm to five pulmonologists and radiological reports. In external validation, the AI algorithm showed areas under the curve (AUC) of 0.951 and 0.975 in validation dataset 1 and 2. The accuracy of the pulmonologists on validation dataset 2 showed AUC range of 0.936-0.995. When abnormal CXRs other than TB were added, AUC decreased in both human readers (0.843-0.888) and AI algorithm (0.828). When combine human readers with AI algorithm, the AUC further increased to 0.862-0.885. The TB CXR AI algorithm developed by using Google teachable machine in this study is effective, with the accuracy close to experienced clinical physicians, and may be helpful for detecting tuberculosis by CXR.

High all-cause mortality and increasing proportion of older adults with tuberculosis in Texas, 2008-2020

Pulmonary tuberculosis (PTB) elimination efforts must consider the global growth of the ageing population. Here we used TB surveillance data from Texas, United States (2008-2020; total n = 10656) to identify unique characteristics and outcomes in older adults (OA, ≥65 years) with PTB, compared to young adults (YA, 18-39 years) or middle-aged adults (40-64 years). We found that the proportion of OA with PTB increased from 15% in 2008 to 24% in 2020 (trend p < 0.05). Diabetes was highly prevalent in OA (32%) but not associated with adverse outcomes. Death was 13-fold higher in OA compared to YA and was 7% at the time of diagnosis which suggests diagnostic delays. However, once TB was suspected, we found no differences in culture, smear, or nucleic acid detection of mycobacteria (although less lung cavitations) in OA. During treatment, OA had less drug-resistant TB, few adverse reactions and adhered with TB treatment. We recommend training healthcare workers to 'think TB' in OA, for prompt treatment initiation to diminish deaths. Furthermore, OA should be added as a priority group to the latent TB treatment guidelines by the World Health Organization, to prevent TB disease in this highly vulnerable group.

The Effect of Diabetes Control Status on CT Findings in Pulmonary Tuberculosis: Emphasis on Bronchial Erosive Changes

PURPOSE

Studies on the effect of diabetes mellitus (DM) on the radiologic findings of pulmonary tuberculosis (PTB) have reported inconsistent results. These findings may have been influenced by the glycemic control status of the patients studied. To our knowledge, no recent data have described the effect of the DM control status on CT findings in PTB in terms of medium-sized airway involvement that is visualized as bronchial erosion on CT. The aim of this present study was to determine whether the DM control status influenced radiological manifestations in patients with PTB, with an emphasis on bronchial erosive changes.

METHODS

We conducted a retrospective single-center study on patients who were newly diagnosed with PTB. A total of 426 consecutive patients with PTB who underwent CT scans at the time of diagnosis from 1 January 2017 to 31 March 2020 were included in this study. The included patients were categorized as having no DM (non-DM), controlled DM, or uncontrolled DM. The patient medical charts, microbiology study results, and pulmonary changes on the CT scans were analyzed.

RESULTS

Among 426 patients with PTB who underwent CT scans at the time of diagnosis, 91 were excluded either due to undetermined hemoglobin A1C (HbA1C) levels (n = 25) or concomitant pulmonary diseases (n = 66) that would make the analysis of the pulmonary changes on CT scans difficult. Finally, 335 patients were included in this study (224 men and 111 women; mean age, 59 years; range, 16-95 years). Among the 335 patients, 82 (24.5%) had DM and 52 of those (63.4%) had an uncontrolled status. The frequency of cavitation (43% vs. 23% vs. 79%, p < 0.001) and bronchial erosion (44% vs. 30% vs. 73%, p < 0.001) was significantly different between the three groups. The uncontrolled DM group showed a high frequency of cavitation and bronchial erosion compared to the non-DM (cavitation, p < 0.001 and bronchial erosion, p < 0.001) and controlled DM groups (p < 0.001 and p < 0.001). However, the frequency of cavitation and bronchial erosion in the controlled DM group was not different compared to the non-DM group.

CONCLUSION

The glycemic status (HbA1C ≥ 7.0), not the presence of DM, influenced the radiologic manifestations of PTB, especially in terms of medium-sized bronchial involvement, appearing as bronchial erosive changes and the feeding bronchus sign on chest CT scans. This difference in the uncontrolled DM group was likely to contribute to the higher frequency of cavitation.

Artificial Intelligence-reported chest X-ray findings of culture-confirmed pulmonary tuberculosis in people with and without diabetes

Objectives

We applied computer-aided detection (CAD) software for chest X-ray (CXR) analysis to determine if diabetes affects the radiographic presentation of tuberculosis.

Methods

From March 2017-July 2018, we consecutively enrolled adults being evaluated for pulmonary tuberculosis in Karachi, Pakistan. Participants had same-day CXR, two sputum mycobacterial cultures, and random blood glucose measurement. We identified diabetes through self-report or glucose >11.1mMol/L. We included participants with culture-confirmed tuberculosis for this analysis. We used linear regression to estimate associations between CAD-reported tuberculosis abnormality score (range 0.00 to 1.00) and diabetes, adjusting for age, body mass index, sputum smear-status, and prior tuberculosis. We also compared radiographic abnormalities between participants with and without diabetes.

Results

63/272 (23%) of included participants had diabetes. After adjustment, diabetes was associated with higher CAD tuberculosis abnormality scores (p < 0.001). Diabetes was not associated with frequency of CAD-reported radiographic abnormalities apart from cavitary disease; participants with diabetes were more likely to have cavitary disease (74.6% vs 61.2% p = 0.07), particularly non-upper zone cavitary disease (17% vs 7.8%, p = 0.09).

Conclusions

CAD analysis of CXR suggests diabetes is associated with more extensive radiographic abnormalities and with greater likelihood of cavities outside upper lung zones.

Burden of active pulmonary tuberculosis among patients with diabetes in Dar es Salaam, Tanzania: a cross-sectional study

OBJECTIVES

We aimed to determine the prevalence, associated factors and describe the chest radiographic findings for active pulmonary tuberculosis (TB) among patients with diabetes mellitus (DM) attending a diabetic clinic in Tanzania.

DESIGN

Cross-sectional study.

SETTING

A diabetic clinic at Temeke Regional Referral Hospital in Dar es salaam, Tanzania.

PARTICIPANTS

Patients with diabetes.

MAIN OUTCOME MEASURES

The prevalence and factors associated with active TB in patients with DM.

RESULTS

Among 623 patients with DM screened, 11 (1.8%); 95% CI 0.9 to 3.1, had active TB of which 6 (54.5%) were GeneXpert positive and 5 (45.5%) were diagnosed based on clinical symptoms and suggestive chest radiographs. The risk of active TB was lower in patients aged 45-64 years compared with age below 45 years (adjusted prevalence ratio (aPR) 0.39, 95% CI (0.11 to 0.42), p=0.001) and in patients with normal chest examination findings compared with patients with crackles or bronchial breathing sounds (aPR 0.02, 95% CI (0.01 to 0.15), p<0.01). The predominant chest radiographic findings were opacification 100% mainly in the upper and mid-lung zones.

CONCLUSION

Diabetics should be screened for pulmonary TB, particularly among individuals aged 45 years and below with crackles or bronchial breathing on auscultation of the chest. High index of suspicion could help in the early detection and control of TB.

Prompt recognition of infectious pulmonary tuberculosis is critical to achieving elimination goals: a retrospective cohort study

INTRODUCTION

All pulmonary tuberculosis (PTB) cases are presumed to be infectious to some degree. This spectrum of infectiousness is independently described by both the acid-fast bacilli smear and radiographic findings. Smear-positive patients with chest radiographic findings that are typical for adult-type PTB are believed to be most infectious.

HYPOTHESIS

Characterisation of the presumed most infectious PTB case is possible by reference to readily available clinical features and laboratory results.

METHODS

Retrospective cohort study of adult, culture-positive PTB cases (151 smear-positive; 162 smear-negative) diagnosed between 1 January 2013 and 30 April 2017 in Canada. We describe cases according to demographic, clinical and laboratory features. We use multivariable multinomial logistic regression to estimate the relative risk ratio (RRR) with 95% CI of features associated with an outcome of smear-positive PTB, characterised by 'typical' chest radiograph findings.

RESULTS

Being Canadian-born, symptomatic, having a subacute duration of symptoms and broad-spectrum antibiotic prescriptions were all more commonly associated with smear-positive than smear-negative disease (36% vs 20%; 95% vs 63%; 88% vs 54%; and 59% vs 28%, respectively). After combining smear status and radiographic features, we show that smear-positive patients with typical chest radiographs were younger, had a longer duration of symptoms (RRR 2.41; 95% CI 1.01 to 5.74 and 2.93; 95% CI 1.20 to 7.11, respectively) and were less likely to be foreign-born, or have a moderate to high-risk factor for reactivation (RRR 0.40; 95% CI 0.17 to 0.92 and 0.18; 95% CI 0.04 to 0.71, respectively) compared with smear-negative patients with atypical chest radiograph findings.

CONCLUSION

A clear picture of the presumed most infectious PTB case emerges from available historical and laboratory information; vigilance for this presentation by front-line providers will support elimination strategies aimed at reducing transmission.

Radiological significance of high-resolution computed tomography for elderly pulmonary tuberculosis patients - an analysis with culture test

Purpose

Pulmonary tuberculosis (PTB) is one of the major health problems in the elderly population, causing significant morbidity and mortality. The aim of this study is to evaluate the significance of the high-resolution computed tomography (HRCT) modality for the diagnosis of PTB, in comparison to culture test.

Material and methods

Thoracic HRCT images of the study population, comprising 124 patients clinically suspected for PTB with smear and culture reports, were analysed for sensitivity and specificity of the HRCT test. Features of active PTB were centrilobular nodules, ‘tree-in-bud’ pattern densities, macro-nodules, consolidations, cavitary lesions, ground-glass opacities, and miliary nodules.

Results

Among the study population, 108 cases presented HRCT features of active PTB and the remaining cases were negative but had presented a few features mimicking PTB. As inferred from positive culture test results, 106 cases had active PTB, the remaining cases were culture negative for PTB. False-positive (FP) or ‘type I error’ cases, and false-negative (FN) or ‘type II error’ cases were ascertained by Bayes’ theorem. Sensitivity (true positive rate) and specificity (true negative rate) of HRCT test were 0.8125 and 0.8571, respectively.

Conclusions

For proper diagnosis the predictive capability, as two values of ‘a posteriori probability’, was computed; the mean value of ‘a posteriori probability’ for HRCT was 0.6358. When its culture test was positive, the HRCT test was 69.56-92.85% efficient in ascertaining positive results with a sample; on the other hand, when its culture test was negative it was 66.66-100% efficient for a negative result. Thus, the HRCT test is considerably dependable.

Tuberculosis associated with diabetes mellitus by age group in Brazil: a retrospective cohort study, 2007–2014

Diabetes mellitus (DM) has important implications for tuberculosis (TB), as it increases the risk for disease activation and is associated with unfavorable TB treatment outcomes. This study analyzed the association between TB and DM (TBDM) in Brazil from 2007 to 2014. This was a retrospective cohort study carried out in 709,429 new cases of TB reported to the national disease notification system of the Brazilian Ministry of Health. Sociodemographic and clinical data, test results, and treatment outcomes were analyzed. TBDM was found in 6.0% of TB cases, mostly in men aged 18-59 years. The lethality rate was 5.1% higher in all age groups with diabetes, except in those older than 60 years of age. The frequency of multi-drug-resistant tuberculosis (MDR-TB) in patients with DM was higher in those without DM, with a 1.6- to 3.8-fold increase in the odds of MDR-TB. The elderly showed an increase in the prevalence of TBDM from 14.3% to 18.2%. Women were more likely to have DM, and elderly women had 41.0% greater chance of having DM. Relapse was significant among patients younger than 17 years of age. TBDM was high in Brazil, affected all age groups, and was associated with unfavorable TB treatment outcomes. We emphasize the need for strategies for the clinical management of diabetic tuberculosis patients in Brazil aiming at minimizing relapses, deaths, and MDR-TB.

Delay in diagnosis of pulmonary tuberculosis increases the risk of pulmonary cavitation in pastoralist setting of Ethiopia

BACKGROUND

Delay in diagnosis and treatment of pulmonary tuberculosis (PTB) leads to severe disease, adverse outcomes and increased transmission. Assessing the extent of delay and its effect on disease progression in TB affected settings has clinical and programmatic importance. Hence, the aim of this study was to investigate the possible effect of delay on infectiousness (cavitation and smear positivity) of patients at diagnosis in Somali pastoralist area, Ethiopia.

METHODS

A cross-sectional study was conducted between December 2017 and October 2018, and 434 newly coming and confirmed PTB patients aged ≥15 years were recruited in five facilities. Data were collected using interview, record-review, anthropometry, Acid-fast bacilli and chest radiography techniques. Log-binomial regression models were used to reveal the association of delay and other factors associated with cavitation and smear positivity, and ROC Curve was used to determine discriminative ability and threshold delays.

RESULTS

Median age of patients was 30 years. Of all, 62.9% were males, and 46.5% were pastoralists. Median diagnosis delay was 49 days (IQR = 33-70). Cavitation was significantly associated with diagnosis delay [P < 0.001]; 22.2% among patients diagnosed within 30 days of illness and 51.7% if delay was over 30 days. The threshold delay that optimizes cavitation was 43 days [AUC (95% CI) = 0.67(0.62-0.72)]. Smear positivity was significantly increased in patients delayed over 49 days [p = 0.02]. Other factors associated with cavitation were age ≤ 35 years [APR (95% CI) =1.3(1.01-1.6)], chronic diseases [APR (95% CI) = 1.8(1.2-2.6)] and low MUAC*female [APR (95% CI) = 1.8(1.2-2.8)]. Smear positivity was also associated with age ≤ 35 years [APR (95% CI) =1.4(1.1-1.8)], low BMI [APR (95% CI) =1.3(1.01-1.7)] and low MUAC [APR (95% CI) =1.5(1.2-1.9)].

CONCLUSION

This study highlights delay in diagnosis of pulmonary TB remained high and increased infectiousness of patients in pastoral settings of Ethiopia. Hence, delay should be targeted to improve patient outcomes and reduce transmission in such settings.

Factors associated with atypical radiological findings of pulmonary tuberculosis

BACKGROUND

Unusual radiological images may delay diagnosis of pulmonary tuberculosis. This study aimed to analyze the risk factors for an atypical radiological image in patients with pulmonary tuberculosis.

METHODS

We retrospectively analyzed data from patients admitted to one hospital from January 2013 to December 2016 for sputum smear-positive lung tuberculosis who underwent chest computed tomography (CT) on admission. Patients whose sputum cultures were positive for general bacteria were excluded. Patient characteristics and laboratory data were compared between patients with cavity and those without and between patients with upper predominant lung involvement and those without.

RESULTS

This study included 94 (93%) of 101 patients who underwent chest CT. The non-cavity group was older, had a greater number of females, had a lower C-reactive protein (CRP) level, and had a lower glomerular filtration rate. Multivariate analysis showed that a low CRP level (OR 0.808; 95% CI 0.674-0.967; p = 0.020) significantly predicted non-cavity pulmonary tuberculosis. The non-upper predominant lung involvement group was older and had a greater number of females, poorer performance status, a higher CRP level, and a lower serum albumin level. A poor performance status (OR 2.155; 95% CI 1.257-3.693; p = 0.005) was found to significantly predict pulmonary tuberculosis with non-upper predominant lung distributions.

CONCLUSIONS

A low CRP level and poor performance status were associated with non-cavity and non-upper predominant lung distribution, respectively, in patients with pulmonary tuberculosis. Tuberculosis patients with these characteristics may present unusual chest images.

Is there a fundamental flaw in Canada's post-arrival immigrant surveillance system for tuberculosis?

BACKGROUND

New immigrants to Canada with a history of tuberculosis or evidence of old healed tuberculosis on chest radiograph are referred to public health authorities for medical surveillance. This ostensible public health protection measure identifies a subgroup of patients (referrals) who are at very low risk (compared to non-referrals) of transmission.

METHODS

To assess whether earlier diagnosis or a different phenotypic expression of disease explains this difference, we systematically reconstructed the immigration and transmission histories from a well-defined cohort of recently-arrived referral and non-referral pulmonary tuberculosis cases in Canada. Incident case chest radiographs in all cases and sequential past radiographs in referrals were re-read by three experts. Change in disease severity from pre-immigration radiograph to incident radiograph was the primary, and transmission of tuberculosis, the secondary, outcome.

RESULTS

There were 174 cohort cases; 61 (35.1%) referrals and 113 (64.9%) non-referrals. Compared to non-referrals, referrals were less likely to be symptomatic (26% vs. 80%), smear-positive (15% vs. 50%), or to have cavitation (0% vs. 35%) or extensive disease (15% vs. 59%) on chest radiograph. After adjustment for referral status, time between films, country-of-birth, age and co-morbidities, referrals were less likely to have substantial changes on chest radiograph; OR 0.058 (95% CI 0.018-0.199). All secondary cases and 82% of tuberculin skin test conversions occurred in contacts of non-referrals.

CONCLUSIONS

Phenotypically different disease, and not earlier diagnosis, explains the difference in transmission risk between referrals and non-referrals. Screening, and treating high-risk non-referrals for latent tuberculosis is necessary to eliminate tuberculosis in Canada.

Detrimental association between diabetes and tuberculosis: An unresolved double trouble

Despite significant efforts made to control tuberculosis (TB) through DOTS program, the increasing burden of diabetes mellitus (DM) threatens the progress in reducing TB-related mortality, particularly in developing countries. In recent years, TB-DM comorbidity continues to remain high in countries where DM is on rampant. DM increases the risk of TB, reactivates the dormant TB and worsens the TB treatment outcome. The present review highlights the current findings regarding the prevalence and association of TB-DM comorbidity along with their public health implications. This review will increase the awareness among researchers, policymakers and clinicians, regarding the current scenario of TB-DM association.

CT findings of pulmonary tuberculosis and tuberculous pleurisy in diabetes mellitus patients

PURPOSE

We aimed to assess computed tomography (CT) findings of pulmonary tuberculosis (TB) and TB pleurisy in diabetes mellitus (DM) patients and to evaluate the effect of duration of DM on radiologic findings of pulmonary TB and TB pleurisy.

METHODS

Ninety-three consecutive patients diagnosed as active pulmonary TB with underlying DM were enrolled in our study. As a control group, 100 pulmonary TB patients without DM were randomly selected. TB patients with DM were subdivided into two subgroups depending on diabetes duration of ≥10 years or <10 years. Medical records and CT scans of the patients were retrospectively reviewed and compared.

RESULTS

Bilateral pulmonary involvement (odds ratio [OR]=2.39, P = 0.003), involvement of all lobes (OR=2.79, P = 0.013), and lymph node enlargement (OR=1.98, P = 0.022) were significantly more frequent CT findings among TB patients with DM compared with the controls. There were no statistically significant differences in CT findings of pulmonary TB depending on the duration of DM.

CONCLUSION

Bilateral pulmonary involvement, involvement of all lobes, and lymph node enlargement are significantly more common CT findings in TB patients with underlying DM than in patients without DM. Familiarity with the CT findings may be helpful to suggest prompt diagnosis of pulmonary TB in DM patients.

Diabetes and Tuberculosis

The increase in type 2 diabetes mellitus (DM) patients in countries where tuberculosis (TB) is also endemic has led to the reemerging importance of DM as a risk factor for TB. DM causes a 3-fold increase in TB risk and a 2-fold increase in adverse TB treatment outcomes. Given the sheer numbers of DM patients worldwide, there are now more TB patients with TB-DM comorbidity than TB-HIV coinfection. There is an urgent need to implement strategies for TB prevention and control among the millions of DM patients exposed to Mycobacterium tuberculosis. This chapter summarizes the current epidemiological, clinical, and immunological knowledge on TB and DM and their clinical and public health implications. These include the underlying mechanisms for TB risk in DM patients and their clinical and sociodemographic characteristics that distinguish them from TB patients without DM. TB-DM comorbidity is posing a new challenge for integrating the short-term care for TB with the long-term care for DM, particularly in low- and middle-income countries.

The impact of glycemic status on radiological manifestations of pulmonary tuberculosis in diabetic patients

Setting

Diabetes mellitus (DM) may increase risk of pulmonary tuberculosis (PTB) and influence its radiological manifestations.

Objective

To evaluate the impact of glycemic status on radiological findings of PTB in diabetic patients.

Methods

Between January 2010 and December 2015, chest radiographs (CXRs) in consecutive 214 DM patients with culture-proved PTB and 123 available thoracic computed tomography (CT) scans were enrolled. An equal number of non-DM patients with similar demographics was included as the control group. Glycemic status was assessed by glycosylated hemoglobin (HbA1c), and a cutoff of 8% was used to further investigate radiological features of diabetic PTB. Two radiologists and one pulmonologist reviewed the chest images independently.

Results

Compared with non-DM patients, primary PTB pattern and extensive disease on CXRs as well as primary PTB pattern, large non-cavitary nodule, more than one cavity in a single lesion, unusual location, and all lobe involvement of lesions on thoracic CT scans were more common in DM patients. Furthermore, diabetics with HbA1c > 8% were more likely to exhibit unusual findings (P < 0.001), far advanced extensive lesions (P < 0.001) on CXRs, lymphadenopathy (P = 0.028), more than one cavity in a single lesion (P < 0.001) and all lobe involvement (P = 0.041) on thoracic CT scans.

Conclusions

Glycemic status influenced radiological manifestations of diabetic PTB. Given an increased risk of atypical radiological presentations of PTB in DM patients, physicians should be alert and pay more attention to those with poor glycemic control.

Concurrence of Tuberculosis and Other Major Diseases

The chronic respiratory disease of tuberculosis (TB) has become one of the most significant infectious diseases because of its high mortality. It also results in serious social and economic problems that challenge global public health. Anti-TB treatment has achieved satisfactory results; however, concurrence with other diseases such as diabetes, silicosis, malnutrition, or immunosuppressive therapy can significantly interfere with the treatment of TB. Though irregular treatment is the overriding cause of treatment failure, drug-resistant TB or severe TB and complications are also significant factors. Respiratory tract infection and respiratory failure are the leading cause of death for TB.

[Diabetes among new cases of pulmonary tuberculosis in Hanoï, Vietnam]

The aim of this study was to analyze all new pulmonary tuberculosis cases and to assess the frequency and consequences of associated diabetes mellitus. Although apparently distinct, these two diseases could be linked, as suspected since decades. The context is the persistent endemicity of tuberculosis and the recent emergence of diabetes, two major health events for developing countries. The study was conducted at National TB hospital in Hanoï, Vietnam, and retrospectively included tuberculosis patients, cases with diabetes and controls without diabetes, collected during a three-year period 2006-2008. Cases associated with HIV infection or other comorbidities potentially affecting mortality were excluded. Among 2867 new pulmonary TB cases, 254 (8.8%) had associated diabetes. Eighty-six cases and 86 matched controls were included. Among cases mean blood glucose at admission was 14.4 mmol/dl, and patients were mostly urban (50% cases vs 32.5% controls, p=0.03). Clinical symptoms were similar in both groups. However, chest X-Ray cavitary images were significantly more frequent among cases (38.3% vs 16.3%, p=0.002, OR=4.1), as did infiltrative images (78% vs 62%, p=0.017, OR=2.55) and positive sputum smears (67.4% vs 47.8%, p=0.014, OR=2.21). In Vietnam, DM is found in quasi 9% of patients with a new diagnosis of primary pulmonary TB. The diabetes-TB patients may have more severe radiologic findings and a higher smear positivity rate. We suggest that in addition to the systematic HIV screening, all new TB patients should also be screened for diabetes.

Cannon ball appearance on radiology in a middle-aged diabetic female

Pulmonary tuberculosis is commonly presented as cavitary lesion and infiltrations. It commonly involves upper lobe. Lower lobe involvement is less common. Various atypical presentations of tuberculosis on radiology are reported like mass, solitary nodule, multi lober involvement including lower lobes. Atypical presentations are more commo in patients with immunocompromised conditions like Diabetes Mellitus, anemia, renal failure, liver diseases, HIV infection, malignancy, patients on immunosuppressive therapy. Cannon ball presentation of pulmonary tuberculosis is extremely rare and not so common. Common causes of cannon ball presentation in lung are metastasis, fungal infections, Wegener's grannulomatosis, sarcoidosis, etc. We report here a case of middle year female with diabetes mellitus presented with atypical symptoms with cannon ball appearance on radiology and found to be of tuberculosis in origin. Thus any patients with immunocompromised condition can present with atypical manifestation of tuberculosis either clinically or radiologicaly in high endemic countries for tuberculosis.

Tuberculosis and diabetes: current state and future perspectives

This review outlines the association between tuberculosis and diabetes, focusing on epidemiology, physiopathology, clinical aspects, diagnosis and treatment, and evaluates future perspectives, with particular attention to developing countries.

Diabetes Is Associated with Worse Clinical Presentation in Tuberculosis Patients from Brazil: A Retrospective Cohort Study

BACKGROUND

The rising prevalence of diabetes mellitus (DM) worldwide, especially in developing countries, and the persistence of tuberculosis (TB) as a major public health issue in these same regions, emphasize the importance of investigating this association. Here, we compared the clinical profile and disease outcomes of TB patients with or without coincident DM in a TB reference center in Brazil.

METHODS

We performed a retrospective analysis of a TB patient cohort (treatment naïve) of 408 individuals recruited at a TB primary care center in Brazil between 2004 and 2010. Data on diagnosis of TB and DM were used to define the groups. The study groups were compared with regard to TB disease presentation at diagnosis as well as to clinical outcomes such as cure and mortality rates upon anti-tuberculosis therapy (ATT) initiation. A composite score utilizing clinical, radiological and microbiological parameters was used to compare TB severity between the groups.

RESULTS

DM patients were older than non-diabetic TB patients. In addition, diabetic individuals more frequently presented with cough, night sweats, hemoptysis and malaise than those without DM. The overall pattern of lung lesions assessed by chest radiographic examination was similar between the groups. Compared to non-diabetic patients, those with TB-diabetes exhibited positive acid-fast bacilli in sputum samples more frequently at diagnosis and at 30 days after ATT initiation. Notably, higher values of the TB severity score were significantly associated with TB-diabetes comorbidity after adjustment for confounding factors. Moreover, during ATT, diabetic patients required more frequent transfers to TB reference hospitals for complex clinical management. Nevertheless, overall mortality and cure rates were indistinguishable between the study groups.

CONCLUSIONS

These findings reinforce the idea that diabetes negatively impacts pulmonary TB severity. Our study argues for the systematic screening for DM in TB reference centers in endemic areas.

Clinicoradiological Profile of Lower Lung Field Tuberculosis Cases among Young Adult and Elderly People in a Teaching Hospital of Madhya Pradesh, India

Aim. To study the clinical and radiological features of lower lung field tuberculosis (LLFTB) in relation to the patients of nonlower lung field tuberculosis (non-LLFTB). Material and Methods. All the patients of lower lung field tuberculosis defined by the lesions below an arbitrary line across the hila in their chest X-rays were included in the study. Their sputum for acid fast bacilli, HIV, blood sugar, and other relevant investigations were performed. Results. The total of 2136 cases of pulmonary tuberculosis was studied. Among them 215 (10%) cases of patients were diagnosed as the case of lower lung field tuberculosis. Females (62%) were more commonly affected. Most common clinical feature in non-LLFTB was cough (69%) followed by fever (65%), chest pain (54.7%), and weight loss (54.4%). Chest X-ray showed predominance of right side (60.9%) in cases of LLFTB. The relative risk of having the LLFTB in diabetes patients, HIV seropositive patients, end stage renal disease patients, and patients on corticosteroid therapy was high. Conclusion. Lower lung field tuberculosis is not an uncommon entity. It is more common in diabetes, HIV positive, end stage renal disease, and corticosteroid treated patients. Clinical and radiological features are different from upper lobe tuberculosis patients.

Impact of diabetes on the natural history of tuberculosis

Tuberculosis (TB) is the number one bacterial killer worldwide and the current increase in type 2 diabetes mellitus patients (DM), particularly in countries where TB is also endemic, has led to the re-emerging importance of DM2 as a risk factor for TB. There is an urgent need to implement strategies for TB prevention among the millions of DM patients exposed to Mycobacterium tuberculosis (Mtb) worldwide, but knowledge is limited on how and when DM2 alters the natural history of this infection. In this review we summarize the current epidemiological, clinical and immunologic studies on TB and DM and discuss the clinical and public health implications of these findings. Specifically, we evaluate the mechanisms by which DM patients have a higher risk of Mtb infection and TB development, present with signs and symptoms indicative of a more infectious TB infection, and are more likely to have adverse TB treatment outcomes, including death. Emphasis is placed on type 2 DM given its higher prevalence in contemporary times, but the underlying role of hyperglycemia and of type 1 DM is also discussed.

Tuberculosis and diabetes mellitus - an underappreciated association

The current review presents up-to-date knowledge on tuberculosis (TB) in diabetic patients. On the basis of available literature, there is little doubt about the close relationship between these two conditions. Diabetes mellitus in this association may still contribute substantially to the burden of TB and negatively affect control of the latter. Chronic hyperglycemia at least to some extent may alter the clinical manifestation, radiological appearance, treatment outcome and prognosis of TB. Although the pathogenesis is not clear, diabetes may impair both innate and adaptive immune responses to Mycobacterium tuberculosis. Eventually, effective screening and dual management of the diseases have to be addressed both in low- and high-income countries in order to limit the negative effects of the forthcoming global diabetes epidemic.

Comparison of epidemiological, clinical, laboratory and radiological features of hospitalized diabetic and non-diabetic patients with pulmonary tuberculosis at razi hospital in ahvaz

Background:

Diabetes mellitus (DM) due to suppressive effect on cellular immunity can impact on progression of tuberculosis (TB).

Objectives:

The aim of this study was to investigate the impact of DM on the epidemiological, clinical and para clinical aspects of pulmonary TB.

Patients and Methods:

The information of 148 admitted pulmonary TB patients in infectious ward of Razi hospital in Ahvaz from 2009 to 2010 was extracted from their medical files. The patients were divided into two groups as TB with DM (n = 36) and TB without DM (n = 112). The related data on epidemiology, signs, symptoms, radiology and sputum smear examination in both groups were compared in SPSS 16 by using chi squared test.

Results:

The mean age of TB with DM patients was higher TB without DM patients (56.6 ± 12.7 vs. 44.8 ± 18.3; respectively, P = 0.006). Whereas cough, night sweating, fever and weigh loss was not statistically different, sputum, hemoptysis and dyspnea was more prominent in TB with DM (69.4%, 33.4%, 44.5% vs. 36.6%, 9.8%, 20.5%; P = 0.005, P = 0.001, P = 0.005, respectively). In chest x-ray, cavitation and reticulonodular pattern was more frequent in TB with DM (55.5%, 22.2% vs. 31.2%, 8% - P = 0.008, P = 0.02, respectively). The rate of sputum smear positivity in TB with DM and TB without DM was 66.6% and 47.3%, respectively (P = 0.03).

Conclusions:

According to the results of this study, in approach to every DM cases suffering of respiratory symptoms such as productive cough, hemoptysis and dyspnea in association with cavitation or miliary mottling in chest x-ray, pulmonary TB should be considered at the top of the differential diagnosis list.

A high-resolution computed tomography-based scoring system to differentiate the most infectious active pulmonary tuberculosis from community-acquired pneumonia in elderly and non-elderly patients

OBJECTIVE

The objective of this study was to use high-resolution computed tomography (HRCT) imaging to predict the presence of smear-positive active pulmonary tuberculosis (PTB) in elderly (at least 65 years of age) and non-elderly patients (18-65 years of age).

METHODS

Patients with active pulmonary infections seen from November 2010 through December 2011 received HRCT chest imaging, sputum smears for acid-fast bacilli and sputum cultures for Mycobacterium tuberculosis. Smear-positive PTB was defined as at least one positive sputum smear and a positive culture for M. tuberculosis. Multivariate logistic regression analyses were performed to determine the HRCT predictors of smear-positive active PTB, and a prediction score was developed on the basis of receiver operating characteristic curve analysis.

RESULTS

Of 1,255 patients included, 139 were diagnosed with smear-positive active PTB. According to ROC curve analysis, the sensitivity, specificity, positive predictive value, negative predictive value, false positive rates and false negative rates were 98.6 %, 95.8 %, 78.5 %, 99.8 %, 4.2 % and 1.4 %, respectively, for diagnosing smear-positive active PTB in elderly patients, and 100.0 %, 96.9 %, 76.5 %, 100.0 %, 3.1 % and 0.0 %, respectively, for non-elderly patients.

CONCLUSIONS

HRCT can assist in the early diagnosis of the most infectious active PTB, thereby preventing transmission and minimizing unnecessary immediate respiratory isolation.

KEY POINTS

• HRCT can assist in the early diagnosis of the infectious active PTB • HRCT imaging is useful to predict the presence of smear-positive active PTB • Predictions from the HRCT imaging are valid even before sputum smear or culture results.

Glycemic control and radiographic manifestations of tuberculosis in diabetic patients

BACKGROUND

Radiographic manifestations of pulmonary tuberculosis (TB) in patients with diabetes mellitus (DM) have previously been reported, with inconsistent results. We conducted a study to investigate whether glycemic control has an impact on radiographic manifestations of pulmonary TB.

METHODS

Consecutive patients with culture-positive pulmonary TB who had DM in three tertiary care hospitals from 2005-2010 were selected for review and compared with a similar number without DM. Glycemic control was assessed by glycated haemoglobin A1C (HbA1C). A pre-treatment chest radiograph was read independently by two qualified pulmonologists blinded to patients' diabetic status. Films with any discordant reading were read by a third reader.

RESULTS

1209 culture positive pulmonary TB patients (581 with DM and 628 without DM) were enrolled. Compared with those without DM, TB patients with DM were significantly more likely to have opacity over lower lung fields, extensive parenchymal lesions, any cavity, multiple cavities and large cavities (>3 cm). The relative risk of lower lung field opacities was 0.80 (95% CI 0.46-1.42) for those with DM with A1C<7%, 2.32 (95% CI 1.36 - 3.98) for A1C 7%-9%, and 1.62 (95% CI 1.12-2.36) for A1C>9%; and that of any cavity over no cavity was 0.87 (95% CI 0.46-1.62) for patients with DM with A1C<7%, 1.84 (95% CI 1.20-2.84) for A1C 7%-9%, and 3.71 (95% CI 2.64-5.22) for A1C>9%, relative to patients without DM.

CONCLUSIONS

Glycemic control significantly influenced radiographic manifestations of pulmonary TB in patients with DM.

Impact of diabetes mellitus on clinical parameters and treatment outcomes of newly diagnosed pulmonary tuberculosis patients in Thailand

BACKGROUND

To assess the clinical and laboratory parameters, response to therapy and development of antituberculosis (TB) drug resistance in pulmonary TB (PTB) patients with diabetes mellitus (DM) and without DM.

METHODS

Using a prospective design, 227 of 310 new cases of culture-positive PTB diagnosed at the Queen Savang Vadhana Memorial Hospital and the Chonburi Hospital between April 2010 and July 2012 that met the study criteria were selected. Data regarding clinical and laboratory parameters, drug susceptibility and treatment outcomes were compared between PTB patients with DM and those without DM. To control for age, the patients were stratified into two age groups (< 50 and ≥ 50 years) and their data were analysed.

RESULTS

Of the 227 patients, 37 (16.3%) had DM, of which 26 (70.3%) had been diagnosed with DM prior to PTB diagnosis and 11 (29.7%) had developed DM at PTB diagnosis. After controlling for age, no significant differences were found between the two groups regarding mycobacterium burden, sputum-culture conversion rate, evidence of multidrug-resistant tuberculosis, frequency of adverse drug events from anti-TB medications, treatment outcomes and relapse rate. The presenting symptoms of anorexia (p = 0.050) and haemoptysis (p = 0.036) were observed significantly more frequently in PTB patients with DM, while the presenting symptom of cough was observed significantly more frequently in PTB patients without DM (p = 0.047).

CONCLUSIONS

Plasma glucose levels should be monitored in all newly diagnosed PTB patients and a similar treatment regimen should be prescribed to PTB patients with DM and those without DM in high TB-burden countries.

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.

CT findings of pulmonary non-tuberculous mycobacterial infection in non-AIDS immunocompromised patients: a case-controlled comparison with immunocompetent patients

OBJECTIVE

To describe CT findings of non-tuberculous mycobacteria (NTM) pulmonary infection in non-AIDS immunocompromised patients (ICPs) and to compare these findings with those in immunocompetent patients.

METHODS

From July 2000 to August 2007, 369 patients (mean age 58.3 years; 169 males and 200 females) with pulmonary NTM infection were retrospectively reviewed. Of these 369 patients, 24 ICPs (mean age 64.8 years; 15 males and 9 females) were identified. 16 patients had diabetes mellitus, and 6 patients had received long-term steroid therapy. One had received solid organ transplantation and one had received high-dose chemotherapy for haematological disease. 24 age- and sex-matched immunocompetent patients (mean age 64.6 years; 15 males and 9 females) were selected as the control group from the same registry. CT images were reviewed in consensus by three chest radiologists, who were blinded to immune status. Each lung lobe was evaluated in terms of extent of the lesion, bronchiectasis, parenchymal opacity and the presence of ancillary findings. results: A total of 287 lobes were evaluated in ICPs and the control group. The ICPs showed a higher prevalence of ill-defined nodules, with cavities and large opacity >2 cm with/without cavity (p=0.03, 0.04 and 0.02, respectively). Regardless of the immune status, the most common CT findings were bronchiectasis and ill-defined nodules without cavity.

CONCLUSION

The most common CT findings of pulmonary NTM infection in ICPs were bronchiectasis and ill-defined nodules, similar to those in the control group. Ill-defined nodules with cavity and large opacity >2 cm with/without cavity were more frequently found in ICPs.

ADVANCES IN KNOWLEDGE

In patients affected by NTM infection, large opacities and cavitation in pulmonary nodules are more frequent in ICPs than in immunocompetent patients.

Effect of age on presentation with diabetes: Comparison of nondiabetic patients with new smear-positive pulmonary tuberculosis patients

Background:

Diabetes mellitus (DM) has been reported to modify the presenting features of pulmonary tuberculosis (PTB), but data regarding the effect of diabetes on the presentation of PTB are highly variable.

Objective:

To determine whether DM alters the demographic, clinical, and radiological manifestations of tuberculosis and whether the effect of diabetes varies with the age group of PTB patients.

Materials and Methods :

This prospective observational study was conducted on new smear-positive PTB patients with DM (PTB-DM group) and non-diabetic PTB patients (PTB group). Patients of both groups were again divided into six age groups (15–29, 30–39, 40–49, 50–59, 60–69, and >70 rears) to analyze and compare the impact of age on clinicoradiological presentations of PTB.

Results:

Patients in the PTB-DM group were significantly older (53.34 ± 14.06 year) in comparison to their nondiabetic counterparts (PTB group) (44.35 ± 18.14 year) (P < 0.001). The former group also had a lower male:female ratio, although the difference was not statistically significant (1.16:1 vs. 2.05:1, P = 0.101). Tuberculin positivity was significantly higher in the PTB group, compared with patients in the PTB-DM group (P < 0.004). The proportion of patients with lower lung field involvement (P = 0.003) and cavitations (P = 0.005) was also higher in the former group compared with the latter.

Conclusion:

Diabetic patients with tuberculosis were relatively older, had lower tuberculin positivity, and higher proportion of lower lung field involvement and cavitation in comparison to nondiabetic patients.