Prevalence of primary immunodeficiency syndromes in tuberculous meningitis: A case-control study

Whole blood transcriptional profiles and the pathogenesis of tuberculous meningitis

Mortality and morbidity from tuberculous meningitis (TBM) are common, primarily due to inflammatory response to Mycobacterium tuberculosis infection, yet the underlying mechanisms remain poorly understood. We aimed to uncover genes and pathways associated with TBM pathogenesis and mortality, and determine the best predictors of death, utilizing whole-blood RNA sequencing from 281 Vietnamese adults with TBM, 295 pulmonary tuberculosis (PTB), and 30 healthy controls. Through weighted gene co-expression network analysis, we identified hub genes and pathways linked to TBM severity and mortality, with a consensus analysis revealing distinct patterns between HIV-positive and HIV-negative individuals. We employed multivariate elastic-net Cox regression to select candidate predictors of death, then logistic regression and internal bootstrap validation to choose best predictors. Increased neutrophil activation and decreased T and B cell activation pathways were associated with TBM mortality. Among HIV-positive individuals, mortality associated with increased angiogenesis, while HIV-negative individuals exhibited elevated TNF signaling and impaired extracellular matrix organization. Four hub genes-MCEMP1, NELL2, ZNF354C, and CD4-were strong TBM mortality predictors. These findings indicate that TBM induces a systemic inflammatory response similar to PTB, highlighting critical genes and pathways related to death, offering insights for potential therapeutic targets alongside a novel four-gene biomarker for predicting outcomes.

The changes and its significance of peripheral blood NK cells in patients with tuberculous meningitis

Objective

Tuberculous meningitis (TBM) is the most severe form of tuberculosis (TB). The purpose of this study was to explore the relationship between the number of natural killer (NK) cells and adaptive immune status, and disease severity in TBM patients.

Methods

We conducted a retrospective study on 244 TB patients and 146 healthy control subjects in the 8th Medical Center of the PLA General Hospital from March 2018 and August 2023.

Results

The absolute count of NK cells in the peripheral blood of TBM patients was significantly lower than that in normal controls (NC), latent tuberculosis infection (LTBI), and non-severe TB (NSTB) patients (p < 0.05). The proportion of TBM patients (48.7%) with a lower absolute count of NK cells than the normal reference value was significantly higher than that in NC (5.2%) and LTBI groups (4.0%) (p < 0.05), and slightly higher than that in NSTB group (36.0%) (p > 0.05). The absolute counts of lymphocyte subsets in TBM combined with other active TB group, etiology (+) group, IGRA (-) group, and antibody (+) group were lower than that in simple TBM group, etiology (-) group, IGRA (+) group, and antibody (-) group, respectively. The CD3+ T, NK, and B cells in BMRC-stage III TBM patients were significantly lower than those in stage I and stage II patients (p < 0.05). The counts of CD3+ T, CD4+ T, and B cells in the etiology (+) group were significantly lower than those in the etiology (-) group (p < 0.05).

Conclusion

The absolute counts of lymphocyte subsets in the peripheral blood of TBM patients were significantly decreased, especially in NK cells. The reduction of these immune cells was closely related to the disease severity and had a certain correlation with cellular and humoral immune responses. This study helps to better understand the immune mechanism of TBM and provides reliable indicators for evaluating the immune status of TBM patients in clinical practice.

Intraspinal and Intracranial Neurotuberculosis, Clinical and Imaging Characteristics and Outcomes in Hospitalized Patients: A Cohort Study (2000-2022)

Neurotuberculosis (neuroTB) is a devastating disease, and is difficult to diagnose. The aim of this study was to analyze the clinical and imaging characteristics, and outcomes of a retrospective cohort (2000-2022) of hospitalized patients diagnosed with intraspinal and intracranial neuroTB. This work was designed through clinical, laboratory and imaging findings. Variables included: demographic data, history of tuberculosis, neurological complications, comorbidities and outcomes. Morbi-mortality risk factors were identified by univariate analysis. The cohort included: 103 patients with intraspinal and 82 with intracranial neuroTB. During the study period, in-hospital mortality of 3% for intraspinal and 29.6% for intracranial neuroTB was estimated. Motor deficit was found in all patients with intraspinal neuroTB. Risk factors for the unfavorable outcome of patients with intraspinal neuroTB were: age ≥ 40 years, diabetes mellitus (DM), diagnostic delay, kyphosis and spondylodiscitis ≥ 3 levels of involvement. Among the patients with intracranial neuroTB, 79/82 (96.3%) had meningitis and 22 patients had HIV infection (10 of them died). Risk factors for mortality from intracranial neuroTB were: HIV infection, hydrocephalus, stroke, lymphopenia and disseminated and gastrointestinal TB. Patients with intraspinal neuroTB had a significant number of destroyed vertebrae that determined their neurological deficit status. The mortality burden in intracranial neuroTB was conditioned by HIV infection and renal transplantation patients.