Induced sputum as a tool for early detection of airway inflammation in connective diseases-related lung involvement

Bronchoalveolar Lavage in Systemic Sclerosis Patients: A Systematic Review

INTRODUCTION

We performed a systematic review of the literature to determine the value of bronchoalveolar lavage (BAL) in evaluating the pulmonary involvement of systemic sclerosis (SSc).

METHODS

Articles published between 1980 and 2019 were retrieved from the databases: PubMed and Scielo. The search was restricted to clinical trials published in English, utilizing the keywords "scleroderma, systemic sclerosis, interstitial lung disease, and bronchoalveolar lavage".

RESULTS

Twenty-two papers were analyzed. A positive correlation was observed between increased BAL cellularity (alveolitis) and worsening clinical symptoms, pulmonary function, and radiological pattern in 2, 11, and 15 studies, respectively. The majority of BAL studies that evaluated interleukin levels, including TNF-α, IL-6, IL-7, and IL-8, observed higher levels in patients with impaired pulmonary function and increased lung involvement.

CONCLUSIONS

Alveolitis and the increase of some cytokines/chemokines in BAL were related to more severe pulmonary disease in SSc in the majority of the studies and seemed to be markers of worse prognosis, but it is unknown whether BAL adds clinical value to the use of the other non-invasive diagnostic procedures.

Sputum quantitative cytometry in patients with interstitial lung disease and chronic cough

BACKGROUND

Chronic cough frequently occurs in patients with diffuse interstitial lung diseases (ILDs), and can have negative effects on quality-of-life. While there are multiple possible contributors to cough in this setting, the contribution and consequences of airway inflammation have not been previously measured. We aimed to estimate the prevalence of airway cellular inflammation in patients with chronic cough and ILD, and examine the interaction between airway inflammation and changes in lung function.

METHODS

We examined all patients with physician-diagnosed ILD and chronic cough who had sputum quantitative cytometry ordered between 2004 and 2018. The prevalence of airway inflammation was estimated by applying previously established criteria for bronchitis. FEV₁ and FVC were compared between individuals based on the presence of airway inflammation. The changes in FEV₁ and FVC were compared between individuals who had their treatment tailored to their sputum result, and those who did not.

RESULTS

Airway inflammation was present in 50% of patients (n = 173), and was associated with lower FEV₁ (1.87 vs 2.05 L, p = 0.043) and FVC (2.39 vs 2.71, p = 0.024). Sputum-guided management of airway eosinophilia was associated with improvements in FEV₁ (+120 vs -205mL, p < 0.0001) and stability of FVC (+13 vs -284mL, p = 0.003).

CONCLUSIONS

Airway inflammation is common in patients with chronic cough and ILD, and its presence may negatively affect lung function. Further research is required to understand if there is a role for quantitative sputum cytometry in this population, particularly if sputum-guided management of airway inflammation could lead to improvements in cough and other ILD outcomes.

Monitoring immune modulation by nutrition in the general population: identifying and substantiating effects on human health

Optimal functioning of the immune system is crucial to human health, and nutrition is one of the major exogenous factors modulating different aspects of immune function. Currently, no single marker is available to predict the effect of a dietary intervention on different aspects of immune function. To provide further guidance on the assessment and interpretation of the modulation of immune functions due to nutrition in the general population, International Life Sciences Institute Europe commissioned a group of experts from academia, government and the food industry to prepare a guidance document. A draft of this paper was refined at a workshop involving additional experts. First, the expert group defined criteria to evaluate the usefulness of immune function markers. Over seventy-five markers were scored within the context of three distinct immune system functions: defence against pathogens; avoidance or mitigation of allergy; control of low-grade (metabolic) inflammation. The most useful markers were subsequently classified depending on whether they by themselves signify clinical relevance and/or involvement of immune function. Next, five theoretical scenarios were drafted describing potential changes in the values of markers compared with a relevant reference range. Finally, all elements were combined, providing a framework to aid the design and interpretation of studies assessing the effects of nutrition on immune function. This stepwise approach offers a clear rationale for selecting markers for future trials and provides a framework for the interpretation of outcomes. A similar stepwise approach may also be useful to rationalise the selection and interpretation of markers for other physiological processes critical to the maintenance of health and well-being.

Induced sputum as a method for detection of systemic sclerosis-related interstitial lung disease

Inducted sputum (IS) is a non-invasive procedure that can be used for collection of airway secretions. The aim of our study is to evaluate the clinical usefulness of IS for detection of airway inflammation in systemic sclerosis (SSc). Bronchoalveolar lavage and IS were performed to 20 patients with SSc. Eighteen patients who were referred to pulmonary medicine for bronchoalveolar lavage due to other reasons were also recruited for cell counts comparisons. Spirometry, echocardiography and thorax CT (HRCT) imaging were also performed to all patients. Mean macrophage and lymphocyte counts were found to be increased in IS of SSc patients compared with that of control (58.4 ± 14.5% vs. 31.3 ± 16.3%, 30.2 ± 15.4% vs. 15.0 ± 11.5% P < 0.001), whereas mean neutrophil count was lower in the SSc patients (4.1 ± 4.5% vs. 17.2 ± 13.1%, P < 0.05). Significant correlations were noted between BAL and IS findings for macrophage (r = 0.55, P = 0.02) lymphocyte (r = 0.65, P < 0.01) and total cell counts (r = 0.45, P = 0.06). IS is an easy and reliable method for the detection of alveolitis and can be used for early detection of lung involvement in scleroderma.

Pulmonary complications: one of the most challenging complications of systemic sclerosis

Pulmonary manifestations of SSc are leading causes of disease-related morbidity and mortality. Key clinical issues relate to the early detection of fibrotic lung disease, the interpretation of its significance, and decisions on when to start therapy. Respiratory symptoms are common in patients with SSc, but physical examination often fails to establish if the underlying cause is interstitial lung disease (ILD), pulmonary arterial hypertension (PAH), impaired locomotion due to systemic disease or loss of fitness. Impaired lung function is usually evident on pulmonary function testing, with the pattern of functional impairment often discriminating usefully between ILD and PAH. The presence of PAH can be indicated by echocardiography and must be confirmed by right heart catheterization. Whereas chest radiographs detect established ILD, high-resolution CT can identify earlier or very mild inflammatory changes. Treatment options for ILD are limited to immunosuppressive agents, notably cyclophosphamide, often given in combination with low-dose prednisolone. Recent studies have shown that cyclophosphamide is effective in stabilizing pulmonary function--especially in patients with severe fibrotic disease--and in improving health-related quality of life. Progression of pulmonary manifestations and responses to treatment are best monitored using pulmonary function testing. For patients with severe end-stage pulmonary fibrosis, lung transplantation may offer a viable alternative therapeutic option.