Factors Associated with Persistent Sputum Positivity at the End of the Second Month of Tuberculosis Treatment in Lithuania

A time-to-event modelling of sputum conversion within two months after antituberculosis initiation among drug-susceptible smear positive pulmonary tuberculosis patients: Implementation of internal and external validation

Delayed sputum conversion has been associated with a higher risk of treatment failure or relapse among drug susceptible smear-positive pulmonary tuberculosis patients. Several contributing factors have been identified in many studies, but the results varied across regions and countries. Therefore, the current study aimed to develop a predictive model that explained the factors affecting time to sputum conversion within two months after initiating antituberculosis agents among Malaysian with drug-susceptible smear-positive pulmonary tuberculosis patients. Retrospective data of pulmonary tuberculosis patients followed up at a tertiary hospital in the Northern region of Malaysia from 2013 until 2018 were collected and analysed. Nonlinear mixed-effect modelling software (NONMEM 7.3.0) was used to develop parametric survival models. The final model was further validated using Kaplan-Meier-visual predictive check (KM-VPC) approach, kernel-based hazard rate estimation method and sampling-importance resampling (SIR) method. A total of 224 patients were included in the study, with 34.4 % (77/224) of the patients remained positive at the end of 2 months of the intensive phase. Gompertz hazard function best described the data. The hazard of sputum conversion decreased by 39 % and 33 % for moderate and advanced lesions as compared to minimal baseline of chest X-ray severity, respectively (adjusted hazard ratio (aHR), 0.61; 95 % confidence intervals (95 % CI), (0.44-0.84) and 0.67, 95 % CI (0.53-0.84)). Meanwhile, the hazard also decreased by 59 % (aHR, 0.41; 95 % CI, (0.23-0.73)) and 48 % (aHR, 0.52; 95 % CI, (0.35-0.79)) between active and former drug abusers as compared to non-drug abuser, respectively. The successful development of the internally and externally validated final model allows a better estimation of the time to sputum conversion and provides a better understanding of the relationship with its predictors.

Safety and Efficacy of 25 mg/kg and 35 mg/kg vs 10 mg/kg Rifampicin in Pulmonary TB: A Phase IIb Randomized Controlled Trial

Background

Globally, no trial data are available on head-to-head comparison between 10 mg/kg and 25/35 mg/kg rifampicin in treating pulmonary tuberculosis during study initiation.

Methods

A multicentric, phase IIb randomized trial recruited 333 new culture-positive, drug-sensitive adult patients with pulmonary tuberculosis to compare safety and efficacy of high-dose rifampicin (R25/R35), against conventional dose (R10) given daily for 8 weeks followed by standard doses for 16 weeks. Main outcomes were treatment-emergent grade 3/4 adverse events (AEs) and time-to-culture conversion in liquid media, assessed by division of AIDS system for grading the severity of adverse events division of AIDS criteria and Kaplan-Meier methods.

Results

In a modified intention-to-treat population of 323 patients (R10: 105/R25: 112/R35: 106), grade 3/4 AEs were reported in 34 patients (R10: 9.5% [10/105], R25: 9.8% [11/112], R35: 12.3% [13/106]) during the intensive phase. Among 23 patients (R10: 3.8% [4/105], R25: 6.3% [7/112], R35: 11.3% [12/106]) with grade 3/4 hepatotoxicity, 15 (R10: 1.9% [2/105], R25: 3.6% [4/112], R35: 8.5% [9/106]) had grade 3/4 hyperbilirubinemia and 9 patients (R10: 1.0% [1/105], R25: 0.9% [1/112], R35: 6.6% [7/106]) developed clinical jaundice. Significant differences observed only between R10 and R35 with hepatotoxicity (P = .039), hyperbilirubinemia (P = .031), clinical jaundice (P = .032), and treatment interruption (P = .039). Eighteen serious AEs and 6 deaths (R10: 3/R25: 1/R35: 2) occurred during study period. Time to stable culture conversion in liquid media was faster in R25 (adjusted hazard ratio, 1.71; 95% confidence interval [CI], 1.26-2.31 [solid: 1.97; 95% CI, 1.46-2.67]) and R35 (1.81; 95% CI, 1.33-2.48 [solid: 2.24; 95% CI, 1.64-3.06]), than R10 (34 vs 44 days). R25 had no failure/relapse.

Conclusions

Hepatotoxicity, clinical jaundice, and treatment interruptions occurred significantly higher with R35 than R10. Because R25 was comparably safe as R10 and also highly efficacious than R10, it may be considered for implementation. Clinical Trials Registration. CTRI/2017/12/010951.

Prevalence and factors associated with sputum smear non-conversion after two months of tuberculosis treatment among smear-positive pulmonary tuberculosis patients in Rwanda: a cross-sectional study

BACKGROUND

Non-conversion of sputum smear prolongs the infectivity of pulmonary tuberculosis patients and has been associated with unfavorable tuberculosis (TB) treatment outcomes. Nevertheless, there is a limited evidence on predictors of sputum smear non-conversion among smear-positive PTB (SPPTB) patients in Rwanda. Therefore, this study aimed to determine the factors associated with sputum smear non-conversion after two months of treatment among SPPTB patients in Rwanda.

METHODS

A cross-sectional study was conducted among SPPTB patients registered in the national electronic TB reporting system by all health facilities countrywide (Rwanda) from July 2019 to June 2021. Eligible patients who had completed the first two months of anti-TB treatment and with smear results at the end of the second month of treatment were included in the study. Bivariate and multivariate logistic regression analyses were done using STATA version 16 to determine the factors associated with sputum smear non-conversion. Adjusted odds ratio (OR), 95% confidence interval (CI), and p-value < 0.05 was considered statistically significant.

RESULTS

This study included 7,211 patients. Of them, 632 (9%) patients had sputum smear non-conversion at the end of the second month of treatment. In multivariate logistic regression analysis, age groups of 20-39 years (AOR = 1.7, 95% CI: 1.0-2.8) and 40-59 years (AOR:2, 95% CI: 1.1-3.3), history of first-line TB treatment failure (AOR = 2, 95% CI: 1.1-3.6), follow-up by community health workers(CHWs) (AOR = 1.2, 95% CI: 1.0-1.5), BMI < 18.5 at TB treatment initiation (AOR = 1.5, 95% CI: 1.2-1.8), and living in Northern Province of Rwanda (AOR = 1.4, 95% CI: 1.0-2.0), were found to be significantly associated with sputum smear non-conversion after two months of treatment.

CONCLUSION

Sputum smear non-conversion among SPPTB patients remains low in Rwanda compared to countries of similar health care setting. Identified risk factors for sputum smear non-conversion among SPPTB patients in Rwanda were age (20-39 years, 40-59 years), history of first-line TB treatment failure, follow up by CHWs, BMI < 18.5 at TB treatment initiation and residence (Northern province).

Treatment outcomes of extended versus nonextended intensive phase in pulmonary tuberculosis smear positive patients with delayed sputum smear conversion: A retrospective cohort study at primary care clinics in Kota Kinabalu

INTRODUCTION

Delayed sputum smear conversion in patients with smear-positive pulmonary tuberculosis is a crucial problem at primary care clinics in Sabah resulting in poor treatment outcomes. This study aimed to compare the treatment outcomes between extended and nonextended intensive phase treatments among patients with delayed sputum smear conversion and to identify the factors associated with unsuccessful treatment outcomes.

METHOD

This retrospective cohort study was conducted using data from a Malaysian tuberculosis registry, medical records and clinic referral emails from five primary care clinics in Kota Kinabalu from January 2014 to December 2018. A total of 163 patients with delayed sputum smear conversion were selected and divided into cohort groups: 90 patients received 3 months of intensive phase treatment (extended intensive phase), and 73 patients received 2 months of intensive phase treatment (non-extended intensive phase).

RESULTS

Of the 163 patients, 33.7% had unsuccessful treatment outcomes (25.2% had treatment failure; 0.6% died; 3.7% defaulted; and 4.3% transferred out), and 3.7% had relapse. There were no significant differences in the prevalence of unsuccessful treatment outcomes (37.6% vs 28.6%, OR=1.51, CI=0.77-2.94, P=0.226) and relapse (2.2% vs 5.7%, 0R=0.36, CI=0.65-2.04, P=0.404) between the extended and non-extended intensive phase groups. High sputum acid-fast bacilli grade (AFB) at 2 months, drug resistance and lack of directly observed treatment, short-course supervision (DOTS) were associated with unsuccessful treatment outcomes.

CONCLUSION

Extended intensive phase treatment in patients with delayed sputum smear conversion does not prevent unsuccessful treatment outcomes and relapse.

Smear grading at initial treatment association with treatment outcomes among new smear positive pulmonary tuberculosis patients: A retrospective study

Introduction

Tuberculosis (TB) is one of the most challenging diseases in diagnosis, treatment and control. We aimed to assess the association of the initial grading of Mycobacterium Sputum Smear (MSS) on the outcomes of TB treatment.

Materials and methods

In a retrospective study, data of 418 positive pulmonary smear patients were retrieved from the TB registration system in Iran during 2014 to 2021. Patients' data included demographic, laboratory and clinical information and were recorded in our checklist. The grading of Mycobacterium Sputum Smear (MSS) at the initial treatment was assessed based on World Health Organization (WHO) guidelines. Chi-square test was used to assess the relationship between tuberculosis treatment outcomes and Mycobacterium grade at initial treatment in SPSS.

Results

The mean age of cases was 51.19 ± 22.29 years old and varied between 14 and 95 years. Laboratory results showed that the rate of 1-9, 1+,2+ and 3+ Mycobacterium tuberculosis was 17.7%, 44.3%, 19.4% and 18.7%, respectively. The rate of cure, death and treatment failure in patients was 87.1%, 6.9%, and 1.2%, respectively. The highest mortality rate (11.5%) occurred in patients with 3+ and the lower rate of cure was 79.5% in this group. Moreover, by increasing the Mycobacterium grade the rate of transferred out and lost to follow up from treatment increased (p = 0.024).

Conclusion

High smear grading of sputum is inversely associated with lower curing and on-time treatment. Moreover, by increasing the Mycobacterium grade at initial treatment, treatment failure and lost to follow up increased Therefore, improvement the health system and patient-diagnosis and screening programs is necessary to on-time diagnosis and facilitate the treatment process.

Systematic assessment of clinical and bacteriological markers for tuberculosis reveals discordance and inaccuracy of symptom-based diagnosis for treatment response monitoring

Background

Clinical symptoms are the benchmark of tuberculosis (TB) diagnosis and monitoring of treatment response but are not clear how they relate to TB bacteriology, particularly the novel tuberculosis-molecular bacterial load assay (TB-MBLA).

Methods

Presumptive cases were bacteriologically confirmed for TB and assessed for symptoms and bacteriological resolution using smear microscopy (SM), culture, and TB-MBLA over 6-month treatment course. Kaplan–Meier and Kappa statistics were used to test the relationship between symptoms and bacteriological positivity.

Results

A cohort of 46 bacteriologically confirmed TB cases were analyzed for treatment response over a 6-month treatment course. Pre-treatment symptoms and bacteriological positivity concurred in over 70% of the cases. This agreement was lost in over 50% of cases whose chest pain, night sweat, and loss of appetite had resolved by week 2 of treatment. Cough resolved at a 3.2% rate weekly and was 0.3% slower than the combined bacteriological (average of MGIT and TB-MBLA positivity) resolution rate, 3.5% per week. A decrease in TB-MBLA positivity reflected a fall in bacillary load, 5.7 ± 1.3- at baseline to 0.30 ± 1.0- log10 eCFU/ml at month 6, and closer to cough resolution than other bacteriological measures, accounting for the only one bacteriologically positive case out of seven still coughing at month 6. Low baseline bacillary load patients were more likely to be bacteriologically negative, HR 5.6, p = 0.003 and HR 3.2, p = 0.014 by months 2 and 6 of treatment, respectively.

Conclusion

The probability of clinical symptoms reflecting bacteriological positivity weakens as the patient progresses on anti-TB therapy, making the symptom-based diagnosis a less reliable marker of treatment response.

The Cavity as a Lasting Abode for Tuberculous Bacilli: An Observational Study

The aim of this study was to determine the factors associated with persistent sputum positivity at the end of 2 months of treatment in patients presenting with (drug-susceptible) pulmonary tuberculosis at a tertiary care hospital in Karachi. A cross-sectional study was conducted at the Department of Chest Medicine (Ward 12), Jinnah Postgraduate Medical Center (JPMC), Karachi, over 6 months. A sample of 73 consenting, newly diagnosed, smear-positive drug-susceptible pulmonary tuberculosis patients was studied. Demographic (age, gender, height, weight and duration of tuberculosis, BMI, socioeconomic, occupational, marital, educational and residential statuses) and clinical factors (chest X-ray extent and cavities, initial smear results, diabetic and smoking statuses) which may be associated with sputum non-conversion were entered in a proforma. Patients were followed up at 2 months of treatment with a sputum smear. Data analysis was done on SPSS (Statistical Package for Social Sciences-version 20.0). Rate of sputum positivity after 2 months of anti-tubercular drug treatment was 17.8%. None of the above-mentioned demographic and clinical factors was associated with persistence of sputum positivity except for the presence of CXR cavities, which made it 5.5 times more likely that the patient would remain smear-positive at 2 months (p = 0.035). The finding of chest radiograph cavities makes it highly likely that a pulmonary tuberculosis patient may remain infectious or have an unfavorable outcome despite taking treatment for 2 months. Clinicians and national policy-makers should thus bear in mind the implications this can have with regard to disease control and therefore pay particular attention to such patients in terms of stringent monitoring and directly observed treatment short-course (DOTS) provision.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s42399-021-01098-6.

Higher Serum Cholesterol Levels Are Associated With Reduced Systemic Inflammation and Mortality During Tuberculosis Treatment Independent of Body Mass Index

Background: Lipids play a central role in the pathogenesis of tuberculosis (TB). The effect of serum lipid levels on TB treatment (ATT) outcomes and their association with serum inflammatory markers have not yet been characterized. Methods: Our retrospective cohort study on drug-susceptible TB patients, at the National Taiwan University Hospital, assessed the association of baseline serum lipid levels such as low-density lipoprotein (LDL), high-density lipoprotein (HDL), total cholesterol (TC) and triglycerides (TG) with all-cause and infection-related mortality during first 9 months of ATT and baseline inflammatory markers namely C-reactive protein (CRP), total leukocyte count (WBC), and neutrophil-lymphocyte ratio (NL ratio). Results: Among 514 patients, 129 (26.6%) died due to any-cause and 72 (14.0%) died of infection. Multivariable Cox-regression showed a lower adjusted hazard ratio (aHR) of all-cause mortality in the 3rd tertiles of HDL (aHR 0.17, 95% CI 0.07-0.44) and TC (aHR 0.30, 95% CI 0.14-0.65), and lower infection-related mortality in the 3rd tertile of HDL (aHR 0.30, 95% CI 0.14-0.65) and TC (aHR 0.30, 95% CI 0.14-0.65) compared to the 1st tertile. The 3rd tertiles of LDL and TG showed no association in multivariable analysis. Similarly, 3rd tertiles of HDL and TC had lower levels of baseline inflammatory markers such as CRP, WBC, and NL ratio using linear regression analysis. Body mass index (BMI) did not show evidence of confounding or effect modification. Conclusions: Higher baseline serum cholesterol levels were associated with lower hazards of all-cause and infection-related mortality and lower levels of inflammatory markers in TB patients. BMI did not modify or confound this association.

Prediction of the duration needed to achieve culture negativity in patients with active pulmonary tuberculosis using convolutional neural networks and chest radiography

BACKGROUND

We aimed to predict the duration needed to achieve culture negativity in patients with active pulmonary tuberculosis using convolutional neural networks (CNNs) and chest radiography.

METHODS

Medical records were searched for eligible patients with culture-confirmed active pulmonary tuberculosis. The eligible patients were randomly assigned to the training dataset group (N = 180) and the validation dataset group (N = 59). Posteroanterior X-ray radiographs in the standing position were obtained at diagnosis. The image data were augmented by a factor of 10 by randomly shifting and rotating the original image. Thus, 1800 images (112 × 112 pixels, 8-bit grayscale) from 180 patients in the training dataset group were used for training the CNN model. The model performance was evaluated on the validation dataset.

RESULTS

The values predicted by the CNN model were significantly associated with the actual values (Pearson's correlation coefficient 0.392, p = 0.002). The mean absolute error was 18.0. The visualization of the layer outputs suggested that the CNN model recognized some of the chest radiographic findings that were useful in predicting the duration needed to achieve culture negativity.

CONCLUSIONS

The CNN model was useful for predicting the duration needed to achieve culture negativity in active pulmonary tuberculosis, although the accuracy was unsatisfactory. This study suggests that chest radiography findings are as important as other clinical factors for prediction and could be learned by the machine.

Sputum smear grading and associated factors among bacteriologically confirmed pulmonary drug-resistant tuberculosis patients in Ethiopia

Background

The sputum smear bacilliary load is a fundamental indicator of the level of infectiousness in DR-TB patients. However, evidence on DR-TB sputum smear grading and its factors in the study setting is limited. This study was aimed to determine the level of sputum smear grading and associated factors among DR-TB patients in Ethiopia.

Methods

This was an institution based cross-sectional study on 520 bacteriological confirmed pulmonary DR-TB patients from September 2010 to December 2017 in the northwest Ethiopia. Epidata 4.2.00 and SPSS 20 were used for data entry and management, respectively. Ordinary logistic regression was fitted. A cut of p-value less than 0.05 in the multivariable ordinary logistic regression was considered to declare statistically significant variables.

Results

Of all 520 bacteriological confirmed pulmonary DR-TB patients; 34.42% had 3⁺, 15.77% had 2⁺, 18.27% had 1⁺, 15.19% had scanty, and 16.35% had negative sputum smear grading results. The odds of having higher sputum smear grades were significantly associated with the patient’s educational status of secondary (Adjusted Odds Ratio (AOR) = 0.43, 95% Confidence Interval (CI): 0.21, 0.89), body mass index of 16 to 18.49 kg/m² (AOR = 1.81, 95%CI: 1.16, 2.84), and TB treatment history of two and more times (AOR = 1.78, 95%CI: 1.24, 2.55).

Conclusions

More than a third of the bacteriological confirmed pulmonary DR-TB patients in the study setting was highly infectious with the highest bacillary load. The odds of having a high bacillary load were significantly associated with the patient’s TB treatment history, nutritional, and educational status.

Predictors of smear non-conversion among new-treatment pulmonary tuberculosis: a single center case-control study in Indonesia

BACKGROUND Previous studies concluded predictors of smear non-conversion pulmonary tuberculosis (TB) globally as well as in Indonesia. However, there is a limited data in hospital setting. This study aimed to explore predictors of smear non-conversion pulmonary TB in hospital setting. METHODS A case-control study was conducted to explore predictors of smear nonconversion among new-treatment pulmonary TB in Dr. Kariadi General Hospital from 2017 to 2019. Number of cases and controls have been determined consecutively. Data were collected from secondary data accessed in medical records and directly from subjects. Non-conversion status in the case group was defined as a persistent sputum smear-positive after 2 months of intensive phase of treatment. The subjects’ characteristics i.e., age, sex, BMI, education level, occupational status, and predictors of smear non-conversion, i.e., patient’s compliance, smoking status, alcohol consumption, presence of drugs side effects, health care access, first acid-fast bacilli (AFB) smear grading, diabetes mellitus (DM), housing condition, housing density, and household income were observed. Chi-square test and binary logistic regression were used. RESULTS 35 subjects were determined in the case group while 76 subjects were the control group and involved in the final analysis. Age, sex, first AFB smear grading, smoking status, housing condition, housing density, and DM were involved in the model of logistic regression. DM (OR = 3.4; 95% CI = 1.19–10.00) and first AFB smear grading (OR = 11.2; 95% CI = 3.86–33.00) were concluded as the predictors of smear nonconversion. CONCLUSIONS DM and first AFB smear grading were the predictors of smear nonconversion among new-treatment pulmonary TB subjects.

Drug-Resistant Tuberculosis: Correlation between Positivity of Acid-Fast Bacilli Sputum and Time to Conversion on Patients with Short-Term Treatment Regimen

Drug-resistant tuberculosis (DR-TB) is a worldwide global burden and related to poor treatment outcomes. Monitoring the progress of DR-TB treatment can be carried out microscopic with Acid-Fast Bacilli (AFB) sputum smear and assessed from the beginning or the first time the patient is diagnosed and monthly to determine the sequential conversion of AFB baseline to the next month twice until it becomes negative. The prolonged conversion has been associated with infectiousness and treatment outcomes. This study was aimed to determine the correlation between positivity of AFB sputum and time to conversion in DR-TB patients with short-term treatment (STR) regimen. An analytic retrospective at hospital collected from medical records of DR-TB patients, from September 2017 to July 2018. Spearman technique was used to analyze the data with p < 0.05. From the total of 151 DR-TB patients on STR regimen, 51 patients were enrolled consisting of 30 (58.8%) males and 21 (41.2%) females with ages average were 51 ± 12.9 years old. Overall, 39 (76.5%) patients had time of AFB conversion in the first month, 9 (17.6%) patients in the second months, 2 (3.9%) patients in the third months, and 1 (2%) patient in the fourth months. Among those patients, 26 (51%) patients had completed the treatment outcomes, 22 (43.1%) were loss to follow-up, 1 (2%) patient had the treatment failure, and 2 (3.9%) were died. There was no significant correlation between AFB sputum baseline (Scanty, 1+, 2+, 3+) with the time to sputum conversion (p > 0.05). AFB sputum have significant correlation with time of culture conversion (p < 0.05), and treatment compliance was not associated with time of AFB sputum conversion (p > 0.05). There was no significant relation between positivity of AFB baseline and time to sputum conversion in DR-TB patients on short-term treatment (STR) regimen. AFB sputum have significant correlation with time of culture conversion in DR-TB patients on short-term treatment (STR) regimen.

Is International Travel an Emerging Issue on Transmission of Beijing Lineage Mycobacterium tuberculosis?

Mycobacterium tuberculosis belonging to Beijing sublineage (BL) is associated with high tuberculosis (TB) transmission, multidrug resistance, and adverse treatment outcomes. Sri Lanka experiences an increase in the number of travellers/workers to and from high TB-burden countries, and there is risk of getting BL strains imported into the country. In this context, a cohort study was conducted to assess the prevalence of BL strains among pulmonary tuberculosis (PTB) patients in the Kandy district of Sri Lanka (a popular tourist destination) and its association with patients' sociodemographic and clinical characteristics. The study population included sputum smear-positive PTB patients diagnosed from February 2018-July 2019. Fresh sputum samples were collected for culturing and conducted polymerase chain reaction using BL-specific primers. Among the 101 patients recruited, presence of BL strains could be ascertained in 94 patients of which 24 (26%; 95% CI: 18%-35%) had BL strains. Prevalence of BL strains was higher among those with high sputum smear grades (2+ and 3+) (P < 0.05) and those who had travelled abroad (P < 0.05). The prevalence was also higher among young people (aged <35 years). Treatment success rates were similar in patients with (83%) and without BL strains (83% vs. 81%; P value = 0.8375). The prevalence of BL strains in Kandy, Sri Lanka, was high compared to previously reported figures in Sri Lanka, and the percentage drives closer to the countries in South East Asia. International travel raises itself as an emerging issue in BL transmission urging the need of policies and practices in immigration/emigration strategies. The study findings have the potential to alter the TB epidemiology in the country and might represent the situation in other underexplored countries as well. Therefore, it is important to monitor the trends and factors related to the prevalence of Beijing strains globally and make decisions as a whole.

A valuable computed tomography-based new diagnostic tool for severe chest lesions in active pulmonary tuberculosis: combined application of influencing factors

The objective of the present investigation was to explore the influencing factors and value of computed tomography (CT) for diagnosing severe chest lesions in active pulmonary tuberculosis (APTB). This retrospective investigation included 463 patients diagnosed with APTB. Relevant clinical features were collected. Patients were assigned to mild/moderate group or advanced group depending on the lesion severity on chest CT, severe chest CT lesion refers to the moderately dense or less diffuse lesion that exceeds the total volume of one lung, or the dense fusion lesion greater than one third of the volume of one lung, or the lesion with cavity diameter ≥4 cm. Independent risk factors for severe lesions were determined by univariate and multivariate logistic regression analyses, and the diagnostic efficiency of the risk factors was assessed by receiver operating characteristic curve (ROC). Chest CT demonstrated that there were 285 (61.56%) cases with severe lesions; multivariate Logistic regression analysis showed dust exposure [odds ratio (OR) = 4.108, 95% confidence interval (CI) 2.416–6.986], patient classification (OR = 1.792, 95% CI 1.067–3.012), age (OR = 1.018, 95% CI 1.005–1.030), and albumin-globulin ratio (OR = 0.179, 95% CI 0.084–0.383) to be independently correlated with severe lesions on chest CT. ROC curve analysis showed the cutoff values of age, albumin-globulin ratio and combined score to be 39 years, 0.918 and −0.085, respectively. The predictive value of combined score area under the curve 0.753 (95% CI 0.708–0.798) was higher than that of any single factor. The combined score of these four factors further improved the predictive efficacy.

Tuberculosis infectious pool and associated factors in East Gojjam Zone, Northwest Ethiopia

Background

Globally, tuberculosis (TB) lasts a major public health concern. Using feasible strategies to estimate TB infectious periods is crucial. The aim of this study was to determine the magnitude of TB infectious period and associated factors in East Gojjam zone.

Methods

An institution-based prospective study was conducted among 348 pulmonary TB (PTB) cases between December 2017 and December 2018. TB cases were recruited from all health facilities located in Hulet Eju Enesie, Enebse Sarmider, Debay Tilatgen, Dejen, Debre-Markos town administration, and Machakel districts. Data were collected through an exit interview using a structured questionnaire and analyzed by IBM SPSS version25. The TB infectious period of each patient category was determined using the TB management time and sputum smear conversion time. The sum of the infectious period of each patient category gave the infectious pool of the study area. A multivariable logistic regression analysis was used to identify factors associated with the magnitude of TB infectious period.

Results

Of the total participated PTB cases, 209(60%) were male, 226(65%) aged < 30 years, 205(59%) were from the rural settings, and 77 (22%) had comorbidities. The magnitude of the TB infectious pool in the study area was 78,031 infectious person-days. The undiagnosed TB cases (44,895 days), smear-positive (14,625 days) and smear-negative (12,995 days) were major contributors to the infectious pool. The overall average median TB management time was 142.4 days (IQR, 98–238 days). Similarly, the average sputum smear conversion time of PTB cases (new and repeat) was 46 days. Residence, knowledge, form of TB, smoking, alcohol history, distance from the facility, comorbidity history and stigma were statistically significant factors TB infectious period (p-value< 0.05).

Conclusions

The magnitude of the TB infectious pool is high even if it is lower than the findings of previous studies. This might be an indicator of poor access to TB services, service delays, low community awareness, impaired facility readiness, and poor transportation. Improving personal awareness and behavior, timely management of commodities, and using the TB management time in TB control are crucial to improving TB control activities.