MICROBIOME AND UVEITIDES. A REVIEW.

Microorganisms inhabiting all surfaces of mucous membranes and skin and forming a complex ecosystem with the host is called microbiota. The term microbiome is used for the aggregate genome of microbiota. The microbiota plays important role in the mechanisms of number of physiological and pathological processes, especially of the hosts immune system. The origin and course of autoimmune diseases not only of the digestive tract, but also of the distant organs, including the eye, are significantly influenced by intestinal microbiota. The role of microbiota and its changes (dysbiosis) in the etiopathogenesis of uveitis has so far been studied mainly in experimental models. Reduction of severity of non-infectious intraocular inflammation in germ-free mice or in conventional mice treated with broad-spectrum antibiotics was observed in both the induced experimental autoimmune uveitis model (EAU) and the spontaneous R161H model. Studies have confirmed that autoreactive T cell activation occurs in the intestinal wall in the absence of retinal antigen. Recent experiments focused on the effect of probiotic administration on the composition of intestinal microbiota and on the course of autoimmune uveitis. Our study group demonstrated significant prophylactic effect of the administration of the probiotic Escherichia coli Nissle 1917 on the intensity of inflammation in EAU. To date, only a few studies have been published investigating intestinal dysbiosis in patients with uveitis (e.g., in Behcets disease or Vogt-Koyanagi-Harada syndrome). The results of preclinical studies will be presumably used in clinical practice, mainly in the sense of prophylaxis and therapy, such as change in the lifestyle, diet and especially the therapeutic use of probiotics or the transfer of faecal microbiota.

Acute elevation of intraocular pressure in patient with hyperlipidemic myeloma.

PURPOSE: To introduce a rare case of patient with hyperlipidemic myeloma and ocular manifestation in form of masquerade syndrome with acute elevation of intraocular pressure (IOP) and hyperviscous retinopathy. RESULTS: 55-year-old man with newly diagnosed hyperlipidemic myeloma and hyperviscous syndrome was acutely referred to our glaucoma outpatient clinic due to problems with his left eye: sudden pain, blurred vision, redness of the eye and IOP of 44 mm Hg. We excluded attack of angle closure glaucoma and found presence of whitish material in the anterior chamber and blood obstructing the iridocorneal angle. Glaucoma therapy was initiated and lavage of the anterior chamber of the left eye with sampling of the aqueous humour for biochemical and cytological examination was performed. Identification of trace amount of cryoprotein in the samples of humour proved diagnosis of masquerade syndrome. Finding of the hyperviscous retinopathy and nonperfusion of wide peripheral areas of retina in both eyes was indicated to laser coagulation of these areas. The patient underwent in the meantime three times plasmapheresis, four cycles of biological therapy and autologous stem cell transplantation reaching complete remission of the myeloma. Local and systemic therapy led to significant clinical finding improvement on the anterior segment and fundus of both eyes. CONCLUSIONS: Masquerade syndrome can be complicated by acute elevation of IOP. Diagnostic lavage of the anterior chamber, local therapy, systemic therapy and close interdisciplinary cooperation contributed to right diagnosis, IOP normalisation, ocular and general condition improvement.

Metronidazole Attenuates the Intensity of Inflammation in Experimental Autoimmune Uveitis.

Autoimmune uveitis is a serious sightthreatening disease that in many cases fails to respond to conventional immunosuppressive or biological therapy. Experimental models used in research allow more detailed study of pathogenesis of the autoimmune process and testing new therapeutic strategies. Recent results show that infection can trigger autoimmune diseases, and some commensal microorganisms are essential in causing disease activity. The aim of this work was to assess the effect of broadspectrum antibiotics - combination of metronidazole and ciprofloxacin or metronidazole alone - on the intensity of intraocular inflammation in experimental autoimmune uveitis (EAU). EAU was induced in mouse strain C57BL/6J by interphotoreceptor retinoid- binding protein in complete Freund's adjuvant and pertussis toxin. The grade of uveitis was assessed clinically and histologically in haematoxylin and eosin- stained tissues. Lymphocytes and macrophages were detected in cryosections using the immunoperoxidase method with antibodies. The therapy was commenced one week before EAU induction and continued throughout the experiment. In addition, metronidazole treatment was also started two weeks before EAU induction. Antibiotics significantly reduced the intensity of uveitis compared to the control group (P < 0.05). The effects of combination of ciprofloxacin and metronidazole and of metronidazole alone were similar when the therapy started one week before EAU induction (P < 0.05). Metronidazole commenced two weeks before EAU induction and throughout the experiment suppressed the intensity of EAU with even higher statistical significance (P < 0.0001). It can be assumed that the high protective effect of metronidazole on EAU intensity may be due not only to its antimicrobial effect, but also to its immunomodulatory activity.