Tear metabolomics help differentiate Sjogren's syndrome from other dry eye diseases

France: Tear metabolomics help differentiate Sjogren's syndrome from other dry eye diseases finds new study published in Ocular surface.

This study discovered a biochemical signature that may be useful as an early biomarker of pSS. This signature has a good diagnostic performance and a simple approach for gathering tears that may be easily replicated in clinics.

Eye dryness is a hardship for patients, reducing their quality of life, particularly in the case of primary Sjogren's syndrome (pSS). The cornerstone of pSS, however, is lacrimal exocrinopathy that leads to the dry syndrome.

Geoffrey Urbanski and colleagues conducted this study with the goal to identify biomarkers in tears in patients with newly diagnosed pSS using metabolomics and data mining techniques and to compare them to other causes of dry eye syndrome.

A prospective cohort of 40 pSS and 40 non-pSS Sicca patients with dryness was studied utilizing a standardized targeted metabolomics method that included liquid chromatography and mass spectrometry. After dividing the examined population into training, validation, and test sets, a metabolomic signature predictive of pSS status was sought using linear (logistic regression with elastic net regularization) and non-linear (random forests) machine learning architectures.

Researchers revealed in this study that the metabolic signature of tears, comprising nine metabolites, may distinguish newly diagnosed pSS patients from individuals suffering from other causes of dryness syndrome. Two amino acids (serine and aspartate), one biogenic amine (dopamine), and six phospholipids were used in the signature: two LysoPC (C18:1, C18:2, C16:1), two SM (C16:0, C22:3), and one PC (aa C42:4). Six phospholipids were found to be elevated in the tears of pSS patients, according to the metabolic signature. In this study, researchers also discovered that the ratio of LysoPC to PC was higher in pSS patients and associated with this assessment.

In conclusion, the authors pointed out that in bigger multicentric research, it would be fascinating to see if one or more of the nine metabolites discovered here might be validated as a clinically meaningful tear biomarker of pSS.

Reference:

Urbanski, G., Assad, S., Chabrun, F., Chao de la Barca, J. M., Blanchet, O., Simard, G., … Reynier, P. (2021). Tear metabolomics highlights new potential biomarkers for differentiating between Sjögren's syndrome and other causes of dry eye. The Ocular Surface, 22, 110–116. doi:10.1016/j.jtos.2021.07.006