Bronchoalveolar lavage cytokine profile in patients with Pulmonary Langerhans Cell Histiocytosis differs from other interstitial lung diseases

Introduction: Langerhans Cell Histiocytosis is a rare disease that in adults uses to affect the lung (PLCH). Disease mechanisms are not fully understood as inflammatory pathways leading to tissue damage has not been fully described. Objectives: To investigate the cytokine bronchoalveolar lavage (BAL) profile in PLCH subjects compare to other interstitial lung disease (ILD). Methods: BAL samples and clinical data were collected from new cases of adult patients with pulmonary PLCH and other ILD referred to an ILD Clinic. Cytokine profile in BAL of these patients were analysed using the Cytokine Human Membrane Antibody Array. Results: Nine patients with PLCH, fourteen with FPI, and twelve smokers with fibrosing ILD (f-ILD) were included. Regarding the 80 cytokine evaluated, when comparing PLCH to others groups there were differences in 73 cytokines. There were no differences between IPF and other f-ILD. There were statistical significant changes in IL-10, CCL-18 and IGFBP-4 (see figure). Conclusions: BAL cytokines in PLCH shows different profile compared to other ILDs. Physiopathological significance of this finding needs further research.