Background: Lymphangioleiomyomatosis can develop in a sporadic form (S-LAM) or in women with tuberous sclerosis complex (TSC). The matrix metalloproteinases (MMPs) are extracellular matrix-degrading enzymes potentially involved in cystic lung destruction, and in the process of migration of LAM cells. The aim of the study was to explore the role of MMP-2 and MMP-7, such as vascular endothelial growth factor (VEGF) -C and -D in women with LAM, including patients with minor pulmonary disease (i.e., <10 lung cysts), and TSC with or without LAM.Methods: We evaluated 50 patients: 13 individuals affected by S-LAM, 20 with TSC-LAM, of whom six with minor pulmonary disease, and 17 with TSC without pulmonary involvement. Sixteen healthy women were used as controls.Results: MMP-2 resulted higher in LAM compared to healthy volunteers, and TSC patients (p = 0.040). MMP-7 was higher in TSC-LAM patient, with even greater values in patients with TSC-LAM minor pulmonary disease, than in S-LAM patients, and in controls (p = 0.001). VEGF-D level was lower than 800 pg/mL in all healthy controls and resulted higher in S-LAM and TSC-LAM than in TSC patients and controls (p < 0.001). VEGF-C values were not statistically different in the study population (p = 0.354). The area under ROC curves (AUCs) of MMP-2, and MMP-7 for predicting LAM diagnosis were of 0.756 ± 0.079 (p = 0.004), and 0.828 ± 0.060 (p < 0.001), respectively. Considering only patients with TSC, the AUCs for MMP-2, and MMP-7 in predicting LAM were 0.694 ± 0.088 (p = 0.044), and 0.713 ± 0.090 (p = 0.027), respectively.Conclusions: Our data suggest that MMP-2 and MMP-7 could be promising biomarkers for LAM diagnosis.

Discriminating between cardiac and pulmonary dyspnea is essential for patients’ management. We investigated the feasibility and ability of forced oscillation techniques (FOT) in distinguishing between acute exacerbation of COPD (AECOPD), and acute decompensated heart failure (ADHF) in a clinical emergency setting. We enrolled 49 patients admitted to the emergency department (ED) for dyspnea and acute respiratory failure for AECOPD, or ADHF, and 11 healthy subjects. All patients were able to perform bedside FOT measurement. Patients with AECOPD showed a significantly higher inspiratory resistance at 5 Hz, Xrs₅ (179% of predicted, interquartile range, IQR 94–224 vs. 100 IQR 67–149; p = 0.019), and a higher inspiratory reactance at 5 Hz (151%, IQR 74–231 vs. 57 IQR 49–99; p = 0.005) than patients with ADHF. Moreover, AECOPD showed higher heterogeneity of ventilation (respiratory system resistance difference at 5 and 19 Hz, Rrs_5-19: 1.49 cmH₂O/(L/s), IQR 1.03–2.16 vs. 0.44 IQR 0.22–0.76; p = 0.030), and a higher percentage of flow limited breaths compared to ADHF (10%, IQR 0–100 vs. 0 IQR 0–12; p = 0.030). FOT, which resulted in a suitable tool to be used in the ED setting, has the ability to identify distinct mechanical properties of the respiratory system in AECOPD and ADHF.