Utility of the monocyte to lymphocyte ratio in diagnosing latent tuberculosis among HIV-infected individuals with a negative tuberculosis symptom screen

Haematological markers as predictive tools for tuberculosis in PLHIV: a retrospective cohort study in Gujarat, India

BACKGROUND

Tuberculosis (TB) remains a significant health challenge among people living with HIV (PLHIV), underscoring the need for early diagnosis and prompt treatment. Hematological parameters have emerged as potential markers for predicting and monitoring TB disease. This study aimed to assess the utility of hematological parameters in predicting TB disease among PLHIV.

METHODS

This retrospective cohort study was conducted at an Antiretroviral Therapy (ART) Centre in Gujarat, India, including PLHIV registered between January 2018 and March 2024. Hematological parameters, including hemoglobin levels, platelet counts, white blood cell differentials, and derived ratios (monocyte-lymphocyte ratio [MLR] and neutrophil-lymphocyte ratio [NLR]), were extracted from medical records. TB diagnosis was based on bacteriological confirmation or clinical criteria. Cox proportional hazards models and Kaplan-Meier survival analyses were performed to assess the association between hematological parameters and TB disease, adjusting for potential confounders.

RESULTS

Among 810 PLHIV, 202 (25%) had TB disease. PLHIV with TB had a higher prevalence of anemia (91.6% vs. 60.0%, p < 0.001), leucocytosis (16.3% vs. 7.6%, p = 0.0004), and neutrophilia (25.2% vs. 9.4%, p < 0.0001) compared to those without TB. A higher MLR ratio (> 0.23) was associated with an increased risk of TB (HR: 5.44, 95% CI: 3.94-7.50, p < 0.001), independent of anemia. Anemia was also an independent predictor of TB (HR: 4.37, 95% CI: 2.72-7.02, p < 0.001).

CONCLUSIONS

Hematological parameters, particularly MLR ratio and anemia status, showed strong associations with TB disease among PLHIV. An MLR > 0.23 was associated with a 5.44-fold increased risk of TB, while anemia increased the risk by 4.37-fold. These readily available and cost-effective markers could enhance early TB detection and risk stratification in PLHIV, especially in resource-limited settings. Integration of these parameters into existing screening protocols may improve targeted interventions and patient outcomes.

Advances in the Diagnosis of Latent Tuberculosis Infection

Latent tuberculosis infection (LTBI) is a critical stage of tuberculosis infection in which Mycobacterium tuberculosis (MTB) is dormant and does not cause active disease. Traditionally, the most commonly used clinical methods for diagnosing LTBI have been the tuberculin skin test (TST) and the interferon-gamma release assay (IGRA). Recently, however, novel skin tests, molecular biology techniques, and cytokine biomarkers have been developed. This review summarizes the latest research on the diagnosis of LTBI, highlighting new tools and methods to improve detection and differentiation from active tuberculosis(ATB).

Utilization of immunological ratios in HIV: Implications for monitoring and therapeutic strategies

Human immunodeficiency virus (HIV) infection remains a significant global health concern, necessitating ongoing research and innovation in the quest for improved disease management. Traditional markers for monitoring HIV progression and the effectiveness of antiretroviral therapy have limitations in capturing the intricate immune responses and inflammatory dynamics in people with HIV. In recent years, the concept of inflammation ratios has gained prominence as a valuable tool for assessing and understanding the complex interplay between inflammation, immune function, and HIV. In this abstract, we provide an overview of the emerging field of utilizing inflammation ratios in the context of HIV and its implications for disease monitoring and therapeutic strategies. These ratios, such as the CD4/CD8 ratio, neutrophil-to-lymphocyte ratio, and monocyte-to-lymphocyte ratio, offer a more comprehensive assessment of an individual's immune status and inflammatory state. By exploring the clinical implications of inflammation ratios, including their potential to predict disease complications and guide personalized treatment approaches, this publication sheds light on the potential benefits of incorporating inflammation ratios into routine HIV care. Furthermore, we emphasize the importance of ongoing research in this field to further refine our understanding of the utility and significance of inflammation ratios in improving the lives of people with HIV.

Monocyte to Lymphocyte ratio is highly specific in diagnosing latent tuberculosis and declines significantly following tuberculosis preventive therapy: A cross-sectional and nested prospective observational study

BACKGROUND

Interferon-gamma release assay and tuberculin skin test use is limited by costly sundries and cross-reactivity with non-tuberculous mycobacteria and Bacille Calmette-Guérin (BCG) vaccination respectively. We investigated the Monocyte to Lymphocyte ratio (MLR) as a biomarker to overcome these limitations and for use in monitoring response to tuberculosis preventive therapy (TPT).

METHODS

We conducted a cross-sectional and nested prospective observational study among asymptomatic adults living with Human Immuno-deficiency Virus (HIV) in Kampala, Uganda. Complete blood count (CBC) and QuantiFERON-TB® Gold-plus were measured at baseline and CBC repeated at three months. Multivariable logistic regression was performed to identify factors associated with a high MLR and decline in MLR.

RESULTS

We recruited 110 adults living with HIV and on antiretroviral therapy, of which 82.5% (85/110) had suppressed viral loads, 71.8% (79/110) were female, and 73.6% (81/110) had a BCG scar. The derived MLR diagnostic cut-off was 0.35, based on which the MLR sensitivity, specificity, positive predictive value, and negative predictive value were 12.8%, 91.6%, 45.5%, and 65.7% respectively. The average MLR declined from 0.212 (95% CI: 0.190-0.235) at baseline to 0.182 (95% CI: 0.166-0.198) after three months of TPT. A viral load of >50 copies/ml (aOR, 5.67 [1.12-28.60]) was associated with a high MLR while that of <50 copies/ml (aOR, 0.07 [0.007-0.832]) was associated with a decline in MLR.

CONCLUSION

MLR was highly specific in diagnosing latent TB and declined significantly following three months of TPT. Implications of a high MLR and decline in MLR after TPT need further evaluation in a larger cohort.

Construction and Validation of a Diagnostic Scoring System for Predicting Active Pulmonary Tuberculosis in Patients with Positive T-SPOT Based on Indicators Associated with Coagulation and Inflammation: A Retrospective Cross-Sectional Study

Introduction

Tuberculosis (TB) is a life-threatening single infectious disease, which remains a major global public health concern. This study was to establish and validate a clinically practical diagnostic scoring system for predicting active pulmonary tuberculosis (APTB) in patients with positive tuberculosis T cell spot test [T-SPOT] using indicators associated with coagulation and inflammation.

Methods

A single-center retrospective cross-sectional study was performed to include patients with positive T-SOPT registered and hospitalized at Wuhan Jinyintan Hospital between January 2017 and December 2019. All patients were separated into the active pulmonary tuberculosis (APTB) group and the inactive pulmonary tuberculosis (IPTB) group, according to the diagnostic criteria from China's Expert Consensus for APTB and IPTB. Subsequently, the patients were randomized into a training set and a validation set at a ratio of 2:1. Indicators associated with coagulation and inflammation, including prothrombin time activity (PTA), activated partial thromboplastin time (APTT), thrombin time (TT), fibrinogen concentration (Fbg-C), C-reactive protein/albumin ratio (CAR), C-reactive protein/prealbumin ratio (CPR), neutrophils count/lymphocyte count ratio (NLR), platelet count/lymphocyte count ratio (PLR), monocyte count/lymphocyte count ratio (MLR), and erythrocyte sedimentation rate (ESR) were obtained from electronic medical record system (EMRS). Stepwise logistic regression was performed in the training set to build a diagnostic model for predicting APTB, which was transformed into an easily applicable scoring system via nomogram. Receiver operating characteristic (ROC) analysis, calibration curve (CC), and decision curve analysis (DCA) were conducted to evaluate the predictive performance of the established diagnostic scoring system.

Results

A total of 508 patients [training set (211 cases of APTB and 116 cases of IPTB) and validation set (103 cases of APTB and 78 cases of IPTB)] with positive T-SPOT were recruited in the study. Stepwise logistic regression showed that CPR, MLR, ESR, APTT and Fbg-C were independent predictors for APTB. The scoring system was subsequently formulated based on the abovementioned predictors, which correspond to scores of 10, 6, 7, 5, and 5, respectively. In addition, patients are more likely to be diagnosed as APTB when the cut-off score was ≥16 scores, while patients with <16 scores are more likely to be diagnosed as IPTB. The scoring system showed good predictive efficacy in both the training set [area under the curve (AUC): 0.887] and the validation set (AUC: 0.898). Furthermore, both CC and DCA confirmed the clinical utility of the scoring system.

Conclusion

The data suggest that the combination of indicators associated with coagulation and inflammation could serve as biomarkers to identify APTB in patients with positive T-SPOT. In addition, patients with positive T-SPOT were more prone to be diagnosed with APTB when having a combined total of scores ≥16 in the scoring system.

Accuracy of monocyte to lymphocyte ratio for tuberculosis diagnosis and its role in monitoring anti-tuberculosis treatment: Systematic review and meta-analysis

BACKGROUND

High monocyte to lymphocyte ratio (MLR) values may be associated with the risk of active tuberculosis (TB) infection in adults, infants, and postpartum women with HIV infection. It may also serve as an indicator of the effectiveness of anti-TB treatment. Thus, the main aim of this study is to ascertain the accuracy of MLR for the diagnosis of TB and its role in monitoring the effectiveness of anti-TB therapy.

METHODS

This systematic review and meta-analysis followed the preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. All statistical analyses were performed using STATA 11 and Meta-DiSc software. The Quality assessment of Diagnostic Accuracy Studies tool was used to evaluate the methodological quality of the included studies. The area under the hierarchical summary receiver-operating characteristic hierarchical summary ROC curve [(HSROC) curve (AUC)] was also calculated as an indicator of diagnostic accuracy.

RESULTS

A total of 15 articles were included in this study. Accordingly, the result showed that elevated MLR is associated with increased risks of TB disease [odd ratio = 3.11 (95% CI: 1.40-6.93)]. The pooled sensitivity and specificity of MLR for identifying TB were 79.5% (95% CI: 68.5-87.3) and 80.2% (95% CI: 67.3-88.9), respectively. The AUC of HSROC was 0.88 (95% CI: 0.857-0.903), indicating the excellent diagnostic performance of MLR for TB. This study also showed that there is a significant reduction in the MLR value after anti-TB treatment in TB patients (standardized mean difference  = 0.68; 95% CI: 0.007, 1.43).

CONCLUSIONS

Generally, MLR can be considered as a crucial biomarker to identify TB and monitor the effectiveness of anti-TB therapy.

Peripheral Blood Markers Correlate with the Progression of Active Tuberculosis Relative to Latent Control of Mycobacterium tuberculosis Infection in Macaques

Despite a century of research into tuberculosis (TB), there is a dearth of reproducible, easily quantifiable, biomarkers that can predict disease onset and differentiate between host disease states. Due to the challenges associated with human sampling, nonhuman primates (NHPs) are utilized for recapitulating the closest possible modelling of human TB. To establish a predictive peripheral biomarker profile based on a larger cohort of rhesus macaques (RM), we analyzed results pertaining to peripheral blood serum chemistry and cell counts from RMs that were experimentally exposed to Mtb in our prior studies and characterized as having either developed active TB (ATB) disease or latent TB infection (LTBI). We compared lung CFU burdens and quantitative pathologies with a number of measurables in the peripheral blood. Based on our results, the investigations were then extended to the study of specific molecules and cells in the lung compartments of a subset of these animals and their immune responses. In addition to the elevated serum C-reactive protein (CRP) levels, frequently used to discern the level of Mtb infection in model systems, reduced serum albumin-to-globulin (A/G) ratios were also predictive of active TB disease. Furthermore, higher peripheral myeloid cell levels, particularly those of neutrophils, kynurenine-to-tryptophan ratio, an indicator of induced expression of the immunosuppressive molecule indoleamine dioxygenase, and an influx of myeloid cell populations could also efficiently discriminate between ATB and LTBI in experimentally infected macaques. These quantifiable correlates of disease were then used in conjunction with a regression-based analysis to predict bacterial load. Our results suggest a potential biomarker profile of TB disease in rhesus macaques, that could inform future NHP-TB research. Our results thus suggest that specific biomarkers may be developed from the myeloid subset of peripheral blood or plasma with the ability to discriminate between active and latent Mtb infection.