Recharacterization of superior limbic keratoconjunctivitis via a subdividing grading method in 236 Chinese patients

Targeted metabolomic analysis of serum free fatty acids: Lipidomics disturbance in patients with superior limbic keratoconjunctivitis

This study aimed to identify and quantify free fatty acids (FFAs), secretory phospholipase A2 group IIa (sPLA2-IIa) and cytosolic phospholipase A2 (cPLA2) in serum of superior limbic keratoconjunctivitis (SLK) patients and explored the association between FFAs, sPLA2-IIa and cPLA2 variations and SLK. Targeted metabolomic analysis of FFAs in serum was performed by gas chromatography tandem mass spectrometry (GC-MS/MS) analysis on 16 SLK patients (43.88 ± 7.88 years; female: 62.50%) and 25 healthy controls (43.12 ± 7.88 years; female: 64.00%). Qualitative and absolute quantitative results of FFAs were obtained and classified according to gender and thyroid tests. Differential lipid metabolites, metabolomic pathways and biomarkers were further evaluated. The serum sPLA2-IIa and cPLA2 were determined by enzyme linked immunosorbent assay (ELISA). Among 40 FFAs identified, 6 FFAs showed significant changes (P < 0.05) in SLK patients, including 4 decreased and 2 increased. They were mainly related to unsaturated fatty acid biosynthesis, α-linolenic acid and linoleic acid metabolism, and fatty acid biosynthesis. When dividing the data by gender or abnormal thyroid tests, some comparable FFAs alterations displayed in SLK patients. The ROC analysis revealed that the AUC values of linoleic acid, γ-linolenic acid, cis-8,11,14-eicosatrienoic acid, stearic acid, and palmitic acid, were all greater than 0.8. The serum concentrations of sPLA2-IIa and cPLA2 in patients with SLK were significantly higher than that in healthy controls. Lipidomics disturbance might be the potential mechanism of SLK. Serum FFA biomarkers associated with SLK have potential for the diagnosis and treatment of the disease.

Risk factors for development of superior limbic keratoconjunctivitis in thyroid eye disease in Japanese

PURPOSE

To analyse risk factors for the development of superior limbic keratoconjunctivitis (SLK) in thyroid eye disease (TED).

METHODS

This prospective, observational study included 638 eyes/sides from 319 patients with TED. The eyes were classified into two groups, based on the presence and absence of SLK. Multivariate logistic regression analysis was performed to evaluate potential risk factors, including sex, patient age, past treatment history (steroid, orbital radiotherapy and radioiodine therapy), smoking, clinical activity score, margin reflex distance (MRD)-1 and -2, Graefe sign/lid lag, Hertel exophthalmometric results, Schirmer's test results, tear break-up time (TBUT) and tear meniscus height (TMH).

RESULTS

SLK was found in 198 eyes (31.0%) from 121 patients. Young age (OR, 0.977; P = 0.006), smoker (OR, 1.785; P = 0.009), presence of Graefe sign (OR, 2.912; P < 0.001), absence of lid lag (OR, 0.485; P = 0.031), high Hertel exophthalmometric values (OR, 1.125; P = 0.002), shorter Schirmer's test results (OR, 0.962; P < 0.001), shorter TBUT (OR, 0.815; P = 0.002) and high upper TMH (OR, 1.003; P = 0.013) were associated with the development of SLK. A high MRD-1 measurement value also tended to be associated with a risk of SLK, with an OR of 1.187 (P = 0.056).

CONCLUSION

The present study proposed several risk factors in relation to the development of SLK in TED.