Reduced Tear Quality Observed in Inflammatory Familial Mediterranean Fever

Inflammatory diseases, such as rosacea and Sjögren syndrome, are associated with increased production of inflammatory cytokines that can impact ocular tissues, such as triggering meibomian gland dysfunction. Familial Mediterranean fever (FMF), an autoinflammatory disorder, also may affect the eye, although there are yet few studies examining meibomian gland (MG) changes in patients with FMF.

Researchers believe FMF’s impact on the eye is rare; but cases of scleritis, episcleritis, uveitis, and rhegmatogenous retinal detachment have been reported. A new cross-sectional investigation has found meaningful differences in tear quantity and quality, and MG number for participants with FMF compared with control individuals, according to data published in Journal Français D’Ophtalmologie.

This study included 42 children diagnosed with FMF for at least 2 years, mean age 11.93±3.92 years; and 36 healthy participants, mean age 11.83±3.38 years, and was conducted at the ophthalmology department of a university hospital in Turkey, from October 2019 to April 2020. Inclusion required that no acute FMF attack was underway. Results revealed functional changes — for patients with FMF, significantly reduced tear attributes were demonstrated in Schirmer II test (P =.022), and tear break-up time (TBUT) (P =.010), although ocular surface disease index (OSDI) scores were more similar (P =.099). 

Significant differences were found in MG dropout (P =.020), MG density (P =.023), and meiboscore (P =.031). Meibum quality ranged from grade 1: clear, to grade 4: toothpaste-like, with 52.4% of the FMF cohort displaying grade 2 or higher, as well as 38.9% of control individuals — but not significantly different (P =.650). The investigation speculates that FMF impacts the number of meibomian glands rather than MG form and structure.

Further, although CIC grades were slightly higher overall for participants with FMF compared with healthy individuals, there was no significant difference between groups (P =.109). This finding points to little change in conjunctival epithelial cells of those with FMF, and no substantial loss of goblet cells. 

FMF primarily affects individuals of Armenian, Arab, Italian, Jewish, North African, or Turkish descent. Previous research involving the ocular surface of those with FMF found significant differences compared with healthy individuals for TBUT, rose bengal and fluorescein staining, and perceived discomfort. Schirmer testing showed no large differences. Substantial goblet cell loss and squamous metaplasia were observed upon CIC in the prior analysis. Differing CIC findings in the present study may be due to the population sample — children with FMF at the university’s pediatric rheumatology clinic are prescribed colchicine upon diagnosis, and the investigation notes it is unclear how 2 years taking this medication affected the results.

All participants with FMF used colchicine, representing a study limitation. Also, rose bengal staining and lissamine green tests were not performed. The strength of this work — it is first to evaluate both morphology and function of MGs in those with FMF. For these individuals, tear film stability can diminish. “Clinicians should be aware of the possibility of ocular surface disease secondary to MG dropout in patients with FMF,” the analysis concludes.

Reference

Bozkurt E, Muhafiz E, Erat YE, et al. Evaluation of the ocular surface, conjunctival impression cytology and meibomian gland dropout in patients with familial Mediterranean fever. J Fr Ophtalmol. Published online September 22, 2021. doi:10.1016/j.jfo.2021.05.007

This article originally appeared on Ophthalmology Advisor