Marjeta Terčelj

Studies on the serum biomarkers of granulomatous inflammation and pulmonary interstitial disease in intrathoracic sarcoidosis have shown conflicting results. We postulated that differences in the concentrations of serum biomarkers can be explained by the heterogenous patterns of sarcoidosis seen on thoracic HRCT. Serum biomarker levels in 79 consecutive patients, newly diagnosed with intrathoracic sarcoidosis, were compared to our control group of 56 healthy blood donors. An analysis was performed with respect to HRCT characteristics (the presence of lymph node enlargement, perilymphatic or peribronchovascular infiltrates, ground-glass lesions, or fibrosis), CXR, and disease extent. Serum levels of CXCL9, CXCL10, CTO, and CCL18 were statistically significantly increased in all patients compared to controls. Serum levels of CA15.3 were statistically significantly increased in all patients with parenchymal involvement. SAA was increased in patients with ground-glass lesions while SP-D levels were statistically significantly increased in patients with lung fibrosis. Only SP-D and CA15.3 showed a significant correlation to interstitial disease extent. In conclusion, we found that sarcoidosis patients with different HRCT patterns of intrathoracic sarcoidosis have underlying biochemical differences in their serum biomarkers transcending Scadding stages. The stratification of patients based on both radiologic and biochemical characteristics could enable more homogenous patient selection for further prognostic studies.

Background: Previous studies have demonstrated a relationship between biomass of fungi exposure in the home and the risk of sarcoidosis. β-glucan was present in the bronchial alveolar lavage fluid (BALF) of patients with sarcoidosis. The Kveim-Siltzbach test reagent (KSTR) induces a sarcoidosis specific, granulomatous, cutaneous response and was used to establish the diagnosis. To date, the granuloma-inducing component of KSTR is still unknown. The present study was undertaken to investigate the presence of β-glucan in the lymph nodes of patients with sarcoidosis and to determine the relationship between the amounts of this agent with disease severity and to investigate the presence of β-glucan in KSTR. Materials and methods: Lymph node aspirations were collected by transbronchial needle aspiration (TBNA) in region R4 or 7 from patients with newly diagnosed sarcoidosis. The samples were treated to isolate β-glucan and analyzed using a Limulus-based assay. Cultures of Propionibacterium ac. and Mycobacterium gordonae as well as samples of Kveim-Siltzbach test reagent were analyzed to determine β-glucan content. Results: A significant relationship was observed between the amount of the β-glucan in the lymph nodes and the extent of granuloma formation in the lung parenchyma, and the size of the lymph nodes in the mediastinum (r=0.787, p=0.0001 and r=0.664, pPropionibacterium ac. and Mycobacterium gordonae contained β-glucan, the levels of which were lower in the Mycobacterium cultures. Comments: The results support the hypothesis that β-glucan, and thus fungal exposure, are involved in the pathogenesis of sarcoidosis.

Composition of organic dust is very complex, involving particles of microbial, animal and plant origin. Several environmental exposure studies associate microbial cell wall agents in organic dust with various respiratory symptoms and diseases. The aim of the present study was to investigate the in vitro effects of the co-exposure of fungal cell wall agents (FCWAs) and bacterial lipopolysaccharide (LPS) on inflammatory immune responses of peripheral blood mononuclear cells (PBMCs) from patients with pulmonary sarcoidosis. PBMCs from 22 patients with pulmonary sarcoidosis and 20 healthy subjects were isolated and stimulated in vitro with FCWAs (soluble and particulate (1 → 3)-β-D-glucan, zymosan and chitosan) and/or LPS. Subsequently, cytokines were measured by ELISA and the mRNA expression of dectin-1, toll-like receptor 2 (TLR2), TLR4 and mannose receptor (MR) was analysed by real-time RT-PCR. Patients with sarcoidosis had a significantly higher secretion of inflammatory cytokines tumour necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), IL-10 and IL-12 (1.7-fold, 2.0-fold, 2.2-fold, and 2.8-fold, respectively; all p < 0.05) after in vitro co-stimulation of PBMCs with FCWAs and LPS. We showed that PBMCs from patients with sarcoidosis had a higher baseline mRNA expression of dectin-1, TLR2, TLR4 and MR (6-fold, 11-fold, 18-fold, and 4-fold, respectively). Furthermore, we found a reduced expression of dectin-1, TLR2 and TLR4 after stimulation with FCWAs and/or LPS, although the reduction was significantly weaker in patients than in healthy subjects. In conclusion, co-stimulation with FCWAs and LPS of PBMC from patients with sarcoidosis caused a weaker reduction of dectin-1, TLR2, TLR4 receptors expression, which could increase the sensitivity of PBMCs, leading to excessive inflammatory cytokine responses and result in the development or progression of pulmonary sarcoidosis.

Chitotriosidase (CTO) was shown to be a good biomarker of sarcoidosis. Increased levels in bronchoalveolar lavage fluid (BALF) were reported and associated with more severe forms of the disease. The aim of the study was to evaluate the value of CTO in BALF as a routine biomarker of sarcoidosis. The study included 85 patients in 9 control subjects in whom serum and BALF CTO were measured. Significantly higher CTO levels were detected in BALF of sarcoidosis patients than in control subjects (p < 0.001). There was good correlation between serum and BALF CTO levels in sarcoidosis patients (Spearman's Rho 0.481, p < 0.001). Serum but not BALF CTO had good correlation with clinical parameters. Only in a group of patients with BALF CTO above upper normal range there was association of BALF CTO with impaired FVC (p = 0.020) and chest radiograph score (0-2 vs. 3-4, p = 0.016). In comparison to serum CTO no additional benefit of determining CTO in BAL for routine sarcoidosis workup was shown.

Chitotriosidase has been found to be useful as a sarcoidosis biomarker. In patients with better outcome lower values were observed. Some subjects have 24-base pair duplication in the chitotriosidase gene (CHIT1) that results in the production of inactive enzyme. This might influence the outcome of sarcoidosis and account for described observations. The aim of this study was to correlate common CHIT1 duplication polymorphism and clinical outcome status in sarcoidosis (COS). This retrospective study comprised 180 patients with sarcoidosis. COS at 3, 5 and 10 years was determined and correlated with CHIT1 24-base pair duplication polymorphism. CHIT1 genotyping was done by the PCR method. There was no significant correlation between CHIT1 24-base pair duplication polymorphism and COS at 3, 5 or 10 years but a subgroup analysis showed higher frequency of patients with Loefgren's syndrome (50% vs. 17.1%) and better COS in CHIT1 24-base pair duplication homozygotes vs. all other subjects in major COS groups (no, minimal and persistent disease) at 3 years (p=0.025) and borderline significant at 5 years (p = 0.090). In this study no correlation between CHIT1 24-base pair duplication polymorphism and COS was shown, but possible protective role of homozygous condition for CHIT1 24-base pair duplication polymorphism is suggested.

Background: Farmer’s lung is one of the most common forms of hypersensitivity pneumonitis (HP). It is a granulomatous inflammatory disease of the pulmonary parenchyma caused by the immune response to inhalatory antigens, mostly actinomycetes or moulds. The diagnostics range from imaging techniques to bronchoalveolar lavage, which demonstrates a typical lymphocytic alveolitis with a low CD4/CD8 ratio in only one third of patients. It is hypothesised that a low CD4/CD8 ratio predicts a prosperous course of the disease, but a high CD4/CD8 ratio lymphocytic alveolitis has yet to be determined to announce a more severe clinical course. Case report: This case report presents a patient with farmer’s lung, with a high CD4/CD8 ratio lymphocytic alveolitis and the dynamics of her disease in relation to her environment and therapy. There was clinical improvement, even without therapy, each time the patient moved away from the risk home environment and a setback when she returned back home. Eventually, lung fibrosis with pulmonary hypertension developed. Conclusion: Our case report does not only illustrate a clear etiological correlation between exposure to causative antigens and progression of farmer's lung, but also emphasises the necessity of early recognition and thorough sanitation of patients’ living space. Furthermore, a high CD4/CD8 ratio lymphocytic alveolitis, which is not typical for HP, is indicative of a continuous exposure to causative agents, leading to chronical inflammation and thus a worse clinical course of the disease.

Late pulmonary sequelae after treatment of childhood cancer

Previous studies have demonstrated increases of inflammatory mediators in sarcoidosis while epidemiological studies have also demonstrated an association with increased fungi exposure. This study measured the level of β-glucan in the lungs and of inflammatory mediators in serum, and correlated both with the extent of pulmonary granuloma infiltration. This is a cross-sectional study of 98 patients with sarcoidosis and 26 controls. β-glucan, a cell wall constituent of fungi, was measured in bronchoalveolar lavage. Inflammatory mediator levels were determined in serum. The extent of granuloma infiltration was estimated on the chest X-ray. Exposure to fungi at home was determined by taking air samples in bedrooms and analysing for the presence of β-N-acetylhexosaminidase. Significantly, higher levels of β-glucan were found in broncho-alveolar lavage in subjects with sarcoidosis as compared with controls. There were significant positive relationships between the extent of granuloma infiltration and the levels of the different inflammatory mediators, except for interleukin-10. Domestic fungal exposure was higher among subjects with sarcoidosis. This is the first time that a specific agent, previously suspected to be related to the risk of sarcoidosis, has been detected in the lung of subjects with sarcoidosis and related to the levels of inflammatory mediators and the degree of home exposure to fungi. The results suggest that exposure to fungi should be explored when investigating patients with sarcoidosis.