TREM-2 Receptor Expression Increases with 25(OH)D Vitamin Serum Levels in Patients with Pulmonary Sarcoidosis.

TREM-1 and TREM-2 molecules are members of the TREM transmembrane glycoproteins. In our previous study we identified increased expressions of TREM-1 and TREM-2 receptors in pulmonary sarcoidosis (PS). Only a few studies concerning the association between vitamin D and TREM receptor expression can be found. The aim of our current study was to determine the association between the levels of an inactive form of 25(OH)D vitamin and TREM-1 and TREM-2 receptor expressions. We have detected low levels of 25(OH)D vitamin in 79% of PS patients. Only 21% of patients had normal serum level of 25(OH)D vitamin with values clustered within the low-normal range. The most striking findings were the increased TREM-2 expressions on myeloid cells surfaces in BALF of PS patients with normal 25(OH)D vitamin serum levels compared with those with its decreased levels. The total number of TREM-2 positive cells was 5.7 times higher and the percentage of TREM-2 positive cells was also significantly increased in BALF of PS patients with normal compared to PS patients with low 25(OH)D vitamin serum levels. A significant correlation between total TREM-2 expression and vitamin D levels has been detected too. However, we have not detected similar differences in TREM-1expression and 25(OH)D vitamin serum levels.

Triggering receptor expressed on myeloid cells-1 and 2 in bronchoalveolar lavage fluid in pulmonary sarcoidosis.

BACKGROUND AND OBJECTIVE: Pulmonary sarcoidosis (PS) is characterized by the formation of granulomas in the lungs and has been associated with infection by microorganisms. Triggering receptor expressed on the surface of myeloid cells (TREM)-1 is overexpressed in response to infection while TREM-2 is involved in granuloma formation. We hypothesized that these receptors are overexpressed in PS and might be useful for diagnostic testing. METHODS: Cell surface TREM-1 and TREM-2 expression in cells obtained at bronchoalveolar lavage (BAL) was measured in individuals with sarcoidosis (n = 26) and compared with that seen in individuals with other interstitial lung diseases (ILD) (n = 27). RESULTS: TREM-1 and TREM-2 expression was significantly increased in sarcoidosis compared with other ILD: total number of TREM-1, P = 0.0039 (23.81 vs 13.50 cells/µl), TREM-2, P < 0.0001 (32.81 vs 7.76 cells/µl); percentage of TREM-1: P = 0.0002 (41.30% vs 15.70%), TREM-2: P < 0.0001 (34% vs 9.60%); and mean fluorescence of TREM-1: P = 0.0005 (5.43 vs 1.96), TREM-2: P = 0.0011 (6.85 vs 2.77). Increase in both of these receptors seems to be typical for PS. In discriminating sarcoidosis from other ILD, the specificity (96%) and sensitivity (72%) of the combination of TREM-1 and TREM-2 was high. CONCLUSIONS: Increased TREM-1 and TREM-2 cell surface expression is observed in sarcoidosis. Evaluation of BAL cell expression of both of these receptors may serve as a diagnostic marker for sarcoidosis.

High mobility group box 1 protein in bronchoalveolar lavage fluid and correlation with other inflammatory markers in pulmonary diseases.

Objectives: Analysis of new markers in bronchoalveolar lavage fluid (BALF) provides new insights into the immunopathogenesis and may be helpful in differential diagnosis of lung diseases. High mobility group box 1 protein (HMGB1) is a non-histone nuclear protein and its release into the extracellular environment may be associated with the inflammatory response. The aim of the study is the analysis of HMGB1 in BALF, correlations with other markers of inflammation and differences in extracellular HMGB1 levels in various lung diagnoses. Methods: The concentration of HMGB1 was tested by an Elisa test. We calculated correlations with other inflammatory markers (leukocytes, total protein, albumin, IgG, IgA, IgM, C3 complement component, alpha-2macroglobuline, CD3, CD4, CD8, TREM-1 and TREM-2) and specified HMGB1 level in various diagnoses. Results: A positive correlation was found between the level of HMGB1 and total protein levels (p=0.0001), albumin (p=0.0058), IgA (p=0.011), IgM (0.0439) and TREM-2 (p=0.0188). Conversely, a negative correlation was revealed between HMGB1 and TREM-1 (p=0.0009). HMGB1 level varied in different diagnoses: the highest level was detected in QuantiFERON TB-positive subjects (median: 30.2) and hypersensitivity pneumonitis (median: 33.2), followed by pulmonary sarcoidosis (median: 16.8) and idiopathic pulmonary fibrosis (median: 8.8). Conclusion: HMGB1 correlates with other inflammatory markers tested in BALF. Its level varies in different lung diagnoses. (Sarcoidosis Vasc Diffuse Lung Dis 2018; 35: 268-275).

Urgent segmental resection as the primary strategy in management of benign tracheal stenosis. A single center experience in 164 consecutive cases.

The report is a retrospective review of 238 benign tracheal stenoses of various etiologies treated between 1995 and 2008. To show that urgent segmental resection has complication rates similar to elective resection and, therefore, preoperative dilation is not necessary, we analysed records of patients who underwent either standard segmental resections with anterolateral mediastinal tracheal mobilization, single-suture anastomosis and neck flexion; or insertion of T-tube with oval-shaped horizontal arm. Primary segmental resection was performed in 164 patients (68.9%), including 14 cases with concomitant tracheo-esophageal fistula (TEF). T-tube as an initial treatment suited 74 (31.1%) patients. We encountered two partial and one complete anastomotic disruptions following subglottic resections treated by T-tube insertion and costal cartilage tracheoplasty or permanent tracheostomy. Restenosis rate in segmental resection was 3.1%. No difference in complication rate between urgent and elective segmental resections was experienced. We treated a small number of patients by endotracheal stent insertion but the results were discouraging. Urgent segmental resection without prior rigid bronchoscopy dilation is our strategy of choice whenever possible. As an alternative to dilation we prefer temporary insertion of modified T-tube. Stand-alone endoluminal dilation and stenting has yet to prove its safety and long-term efficacy.