Krebs von den Lungen-6 (KL-6) in cerebrospinal fluid from neurosarcoidosis patients
Keywords:
neurosarcoidosis, Krebs von den Lungen-6, cerebrospinal fluidAbstract
Background: Krebs von den Lungen-6 (KL-6) is a high molecular weight (MW) glycoprotein mainly secreted by type II pneumocytes because of lung damage or during regeneration. Neurosarcoidosis (NS), where sarcoid granulomas involve the nervous system, occurs in 5-20% of patients with sarcoidosis. No data is currently available on KL-6 in serum or CSF of NS patients. The present study compared KL-6 concentrations in serum and CSF of NS patients versus others with neurodegenerative (ND) or chronic inflammatory demyelinating (DM) diseases.
Materials and methods: Nine NS patients (mean age 46.2 years, range 16-61 years, M/F 5/4), nine patients with a chronic neurodegenerative disease (mean age 53.1 years, range 37-65 years, M/F 5/4) and nine patients with a chronic demyelinating disease (mean age 46.3 years, range 18-65 years, M/F 5/4) were retrospectively enrolled.
Results: Measurable CSF concentrations of KL-6 were detected in 7/9 NS patients but in no ND or DM patients. No significant differences in CSF concentrations of ACE were observed between the three groups (p=0.0819). In NS patients, CSF concentrations of KL-6 were directly correlated with CSF albumin index (r=0.98; p<0.0001), albumin (r=0.979, p=0.0001), IgG (r=0.928, p=0.0009) and total protein concentrations (r=0.945, p=0.0004).
Discussion: KL-6 is a high MW protein, under physiological conditions it is unlikely to cross the blood-brain barrier. We found KL-6 in CSF from NS and not from ND and DM patients. The finding sustains the specificity of changes in KL-6 in this granulomatous disease, suggesting it as a candidate biomarker for recognition of NS.
References
d’Alessandro M, Bergantini L, Cameli P, et al. Serum Concentrations of KL-6 in Patients with IPF and Lung Cancer and Serial Measurements of KL-6 in IPF Patients Treated with Antifibrotic Therapy. Cancers (Basel). 2021 Feb 9;13(4).
Fritz D, van de Beek D, Brouwer MC. Clinical features, treatment and outcome in neurosarcoidosis: systematic review and meta-analysis. BMC Neurol. 2016 Nov 15;16(1):220.
Bathla G, Singh AK, Policeni B, Agarwal A, Case B. Imaging of neurosarcoidosis: common, uncommon, and rare. Clin Radiol. 2016 Jan;71(1):96–106.
Stern BJ, Royal W, Gelfand JM, et al. Definition and Consensus Diagnostic Criteria for Neurosarcoidosis: From the Neurosarcoidosis Consortium Consensus Group. JAMA Neurol. 2018 Dec 1;75(12):1546–53.
Zajicek JP, Scolding NJ, Foster O, et al. Central nervous system sarcoidosis--diagnosis and management. QJM. 1999 Feb;92(2):103–17.
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Copyright (c) 2023 Silvia Bocci, miriana d'alessandro, Laura Bergantini, Alfonso Cerase, Monica Ulivelli, Paola Rottoli, Dalila Cavallaro, Sara Gangi, Elena Bargagli, Fabio Giannini

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