Polymorphisms and haplotypes of TOLLIP and MUC5B are associated with susceptibility and survival in patients with fibrotic hypersensitivity pneumonitis.

INTRODUCTION AND OBJECTIVES: Hypersensitivity pneumonitis (HP) is an interstitial lung disease with diverse clinical features that can present a fibrotic phenotype similar to idiopathic pulmonary fibrosis (IPF) in genetically predisposed individuals. While several single nucleotide polymorphisms (SNPs) have been associated with IPF, the genetic factors contributing to fibrotic HP (fHP) remain poorly understood. This study investigated the association of MUC5B and TOLLIP variants with susceptibility, clinical presentation and survival in Portuguese patients with fHP. MATERIAL AND METHODS: A case-control study was undertaken with 97 fHP patients and 112 controls. Six SNPs residing in the MUC5B and TOLLIP genes and their haplotypes were analyzed. Associations with risk, survival, and clinical, radiographic, and pathological features of fHP were probed through comparisons among patients and controls. RESULTS: MUC5B rs35705950 and three neighboring TOLLIP variants (rs3750920, rs111521887, and rs5743894) were associated with increased susceptibility to fHP. Minor allele frequencies were greater among fHP patients than in controls (40.7% vs 12.1%, P<0.0001; 52.6% vs 40.2%, P = 0.011; 22.7% vs 13.4%, P = 0.013; and 23.2% vs 12.9%, P = 0.006, respectively). Haplotypes formed by these variants were also linked to fHP susceptibility. Moreover, carriers of a specific haplotype (G-T-G-C) had a significant decrease in survival (adjusted hazard ratio 6.92, 95% CI 1.73-27.64, P = 0.006). Additional associations were found between TOLLIP rs111521887 and rs5743894 variants and decreased lung function at baseline, and the MUC5B SNP and radiographic features, further highlighting the influence of genetic factors in fHP. CONCLUSION: These findings suggest that TOLLIP and MUC5B variants and haplotypes may serve as valuable tools for risk assessment and prognosis in fibrotic hypersensitivity pneumonitis, potentially contributing to its patient stratification, and offer insights into the genetic factors influencing the clinical course of the condition.

Distinct TNF-alpha and HLA polymorphisms associate with fibrotic and non-fibrotic subtypes of hypersensitivity pneumonitis.

INTRODUCTION: Since Hypersensitivity Pneumonitis (HP) categorization in fibrotic and nonfibrotic/inflammatory types seems to be more consistent with the distinctive clinical course and outcomes, recent international guidelines recommended the use of this classification. Moreover, fibrotic subtype may share immunogenetic and pathophysiological mechanisms with other fibrotic lung diseases. AIM: To investigate HLA -A, -B, -DRB1 and TNF-α -308 gene polymorphisms among fibrotic and nonfibrotic HP patients due to avian exposure, also in comparison with asymptomatic exposed controls. METHODS: We prospectively enrolled 40 HP patients, classified as fibrotic or nonfibrotic/inflammatory, and 70 exposed controls. HLA and TNF-α polymorphisms were determined by polymerase chain reaction-sequence specific primer amplification. RESULTS: While HLA alleles were not associated to HP susceptibility, fibrotic HP patients showed increased frequencies of HLA A*02 (46.7% vs 25.7%; OR=2.53, p = 0.02) and HLA DRB1*14 (10.0% vs 0.7%; OR=15.44, p=0.02) alleles when compared with exposed controls, although not statistically significant after correction for multiple comparisons. TNF-α G/G genotype (associated with low TNF-α production) frequencies were significantly increased among the non-fibrotic/inflammatory HP patients comparatively to fibrotic presentations (88% vs 60%; RR=0.44; p=0.04) and controls (88% vs 63%, OR 4.33, p=0.037). Also, these patients had a significantly increased frequency of the G allele (94.0% vs 73.3%, RR=0.44, p=0.01), while fibrotic HP patients predominantly presented the A allele (26.7% vs 6.0%, RR=2.28, p=0.01). CONCLUSIONS: Our results support the hypothesis that fibrotic and non-fibrotic HP subtypes exhibit a distinct profile of TNF-α and HLA polymorphisms, which may be relevant to predict disease course and better define treatment strategies.

Predictors of immune-related adverse events and outcomes in patients with NSCLC treated with immune-checkpoint inhibitors.

OBJECTIVE: To identify predictors of immune-related adverse events (IRAEs) in patients with non-small cell lung cancer (NSCLC) treated with immune checkpoint inhibitors (ICIs). Assess associations between outcomes and the development of IRAEs. METHODS: Retrospective analysis of patients with NSCLC treated with ICIs between 2016 and 2020 in the Pulmonology Department of our hospital. Patients with and without IRAEs were compared. A logistic regression analysis was performed to determine predictors of IRAEs. Progression-free survival (PFS) and overall survival (OS) curves were calculated using the Kaplan-Meier method, and the long-rank test was used to assess survival differences between groups. Univariate and multivariate Cox proportional-hazards regression models were used to identify factors associated with PFS and OS. The value considered statistically significant was p≤0.05. RESULTS: A total of 184 patients (77.7% men, mean age 66.9±9.5 years) treated with ICIs were analyzed. During follow-up, 49 (26.6%) patients developed IRAEs and 149 (81.0%) died. According to the multivariate logistic regression analysis, treatment with statins (OR:3.15; p = 0.007), previous systemic corticosteroid therapy (OR:3.99; p = 0.001), disease controlled as response to ICI (OR:5.93; p < 0.001) and higher hemoglobin values (OR:1.28; p = 0.040) were independent predictors for the development of IRAEs. Patients who developed IRAEs had significantly longer medians of PFS (41.0 vs 9.0 weeks, p < 0.001) and OS (89.0 vs 28.0 weeks; p < 0.001). CONCLUSIONS: Patients treated with statins, pre-ICI systemic corticosteroids, higher baseline hemoglobin value and controlled disease as initial response to ICI had a higher risk of developing IRAEs. The development of IRAEs was associated with better outcomes.

The role of interventional bronchoscopy in the management of post-intubation tracheal stenosis: A 20-year experience.

PURPOSE: Benign tracheal stenosis management is still controversial, and there is no international consensus on the best treatment option. Thus, we aimed to look into the history of PITS and the different strategies used in its treatment. The importance of bronchoscopic treatment was also defined, and its effectiveness and safety were assessed. METHODS: Retrospective study of patients diagnosed with PITS, who were referred to the Bronchology Department between January 1996 and December 2016. RESULTS: Of 115 patients enrolled (mean age 48.5±17.6 years, 53% males), 66.1% had complex stenosis. The most common causes of intubation were respiratory (29.9%), neurological (26.8%) and surgical (19.6%). Complex stenosis was caused by longer intubation, and was more frequent among previously tracheostomized patients. The most common location was the upper third of trachea (60.9%). Most cases were initially treated by interventional bronchoscopy, and although serial dilations were effective in some complex PITS, a higher proportion of simple stenosis was successfully managed with this treatment option. Long-term recurrence after serial dilation was observed in 25.0% of cases. Stent placement was required (19.1%) only for complex PITS. Stent-related complications were frequent (61.9%) and linked to the stenting time (p<0.001). Overall, there were no procedure-related complications. Surgical intervention was also performed (30.0%), always with complex PITS. Post-surgical recurrences were observed in 24.2% of cases. CONCLUSIONS: Interventional bronchoscopy is an efficient and safe modality in PITS management. Further studies are needed for better classification and improved knowledge of PITS pathogenesis, and to achieve international consensus of definition to guide clinicians in their practice.