Neutrophil-Lymphocyte Ratio (NLR): A Key to Monitoring TB in Diabetes?
"New Research Explores NLR as a Marker for Tuberculosis Disease Activity in Patients with Diabetes"
Tuberculosis (TB) remains a major global health challenge, especially when it occurs alongside diabetes mellitus (DM). The co-occurrence of TB and DM, often termed TB-DM, poses unique challenges in diagnosis and management. Patients with both conditions often experience altered immune responses, making it crucial to find reliable markers that can indicate disease activity.
In a recent study presented at Respirology, researchers investigated the potential of using the neutrophil-lymphocyte ratio (NLR) as an indicator of disease activity in TB-DM patients. NLR is a simple, cost-effective marker derived from a routine blood test, reflecting the balance between neutrophils (a type of white blood cell involved in inflammation) and lymphocytes (another type of white blood cell crucial for immune response).
The study aimed to determine if NLR could serve as a valuable tool for clinicians in assessing disease activity in TB-DM patients, potentially leading to more tailored and effective treatment strategies.
The Global TB Burden and Integrated Care
The World Health Organization reported 10 million tuberculosis cases and 1.3 million TB-related deaths in 2017. The WHO identifies integrated, patient-centred care for people with TB and comorbidities, including diabetes, as part of Pillar 1 of the End TB Strategy; Member States committed to developing community-based integrated services at the 2018 UN high-level meeting on TB. Data on diabetes prevalence and screening yield among people with TB can help assess the burden of TB-diabetes comorbidity and inform resource allocation and planning. The WHO publishes a global TB report annually to assess the epidemic and progress in prevention, diagnosis, and treatment.
NLR: A Promising Marker in TB-DM?
The study involved a retrospective analysis of data from 181 patients, including 89 with TB-DM and 92 with TB alone. Researchers analyzed blood samples to calculate NLR values and assessed their correlation with disease activity.
- The best cut-off value of NLR was determined to be 2.9.
- Patients with an NLR greater than 2.9 were considered to have immunocompromised status.
- Patients with an NLR less than 2.9 were considered immunocompetent.
- The area under the ROC curve was 0.726 with 95% CI.
- At a cut-off of 2.9, NLR displayed a sensitivity of 67%, a specificity of 66%, a positive predictive value (PPV) of 61.7%, a negative predictive value (NPV) of 71.7% and accuracy value was 66.8.
Recent Reviews on TB-Diabetes Biomarkers
A 2025 review reports that studies have found changes in immune profiles among people with TB and diabetes, particularly in the frequencies and functions of key immune cells. Another 2025 review describes diabetes as a major risk factor for TB, reporting a threefold increase in the risk of active disease and worse treatment outcomes in people with the comorbidity. A study on diabetes screening among people with TB was published on PubMed on March 4, 2026, with the WHO departments for HIV, tuberculosis, hepatitis and sexually transmitted infections, and noncommunicable diseases and mental health named in its listing, alongside a study on preventive treatment of latent TB infection in people with diabetes.
Treatment Challenges in TB-Diabetes
A 2026 paper examines TB-diabetes disease burden alongside the growing challenge of antimicrobial resistance, using a One Health framework to synthesize epidemiological evidence, discuss mechanisms, and evaluate technological approaches. A review identifies drug-drug interactions, autophagy, and treatment challenges among the issues associated with TB-diabetes comorbidity. A 2025 narrative review cites a systematic review and meta-analysis on diabetes, multidrug-resistant TB, and treatment failure in people with TB-diabetes. A 2025 biomarker review covers microbial, metabolic, immunological, inflammatory, clinical, and genetic markers, illustrating the range of marker categories under consideration.
A Double Public Health Burden
A 2024 review characterizes the combined burden of tuberculosis and diabetes mellitus as a major public health challenge. It calls for urgent and integrated approaches to address the two diseases. The source frames the issue broadly and does not provide comparative figures or assess a specific biomarker such as the neutrophil-lymphocyte ratio.
Implications and Future Directions
The study highlights the potential of NLR as a readily accessible and cost-effective marker for assessing disease activity in TB-DM patients. By identifying patients with compromised immune systems (NLR > 2.9), clinicians may be able to tailor treatment strategies more effectively.
Improving Diabetes Detection in People With TB
A screening study reports that diabetes is common among people with TB, and that screening yield was greater in the Eastern Mediterranean and South-East Asia regions, where diabetes prevalence was higher. The study notes substantial heterogeneity across studies and a lack of comparison groups without TB as limitations. It concludes that further research is needed to optimize approaches for detecting diabetes among people with TB. These findings point to screening strategy as an area for future study, rather than establishing a specific optimal approach.
However, the researchers also acknowledge that many factors can affect NLR, indicating that it should be used in conjunction with other clinical and diagnostic parameters. Further research is needed to validate these findings in larger, prospective studies and to explore the underlying mechanisms linking NLR to disease activity in TB-DM.
Ultimately, integrating NLR assessment into the routine management of TB-DM could lead to improved patient outcomes and more personalized approaches to tackling this complex co-infection.