Onchocerca jakutensis ocular infection in Poland: a new vector-borne human health risk?

BACKGROUND: Zoonotic onchocerciasis is a vector-borne disease, which involves many animal species, including large ungulates, boars, dogs, and sporadically, humans. So far, 39 cases of zoonotic onchocerciasis have been reported worldwide, 30 of which have been found in the last 20 years. Onchocerca nematodes are transmitted to humans by blood-sucking vectors during a blood meal. The following species have been responsible for zoonotic infections: Onchocerca cervicalis, O. dewittei japonica, O. gutturosa, O. jakutensis and O. lupi. In humans, the worms have usually been found in the subcutaneous tissues where they form subcutaneous nodules, induce inflammation of musculature, or penetrate the eye. Thirteen ocular zoonotic onchocerciasis cases have been reported so far. In the eye, nematodes were localized in the subconjunctival space, anterior chamber and within the vitreous body. METHODS: In a 39-year-old male patient, a writhing worm in the vitreous body of the left eye was detected and surgically removed. Laboratory identification of the worm was based on macroscopic and molecular identification, based on sequencing of the cytochrome c oxidase subunit 1 gene (cox1). Phylogenetic analysis of the first 250 nucleotide sequences showing the highest levels of similarity with the present isolate in a BLAST analysis was performed. RESULTS: Here, we report the first case worldwide of human ocular infection with O. jakutensis, a natural parasite of red deer. By exploiting a PCR assay, we detected the sequence almost identical to O. jakutensis (GenBank: KT001213.1; positions 1-650) with a single mismatch G/A at position 622. The sequence reported in this paper was deposited in the GenBank database under the accession number MK491767. CONCLUSIONS: Our case together with the previous case reports indicate that zoonotic Onchocerca worms exhibit no tissue specificity and an eye infection has been described in over one third of human zoonotic onchocerciasis cases. In terms of the growing number of cases of zoonotic onchocerciasis in Europe, the USA and Japan, attention should be paid to the diagnosis of subcutaneous nodules and eye infestations.

The effects and safety of intravitreal triamcinolone injections in the treatment of diabetic macular edema.

BACKGROUND: Diabetic macular edema (DME) is responsible for three-quarters of vision-loss cases in diabetic eye disease. In most cases, early treatment by laser photocoagulation can only stabilize vision. Glucocorticoids have been used as a local pharmacological treatment in DME when the inflammation seems to have a pathological background. OBJECTIVES: The aim of the study was to establish the effectiveness and safety of intravitreal triamcinolone injections in the treatment of DME. MATERIAL AND METHODS: Twenty mg intravitreal injections of triamcinole acetonide (IVTA) were applied to 110 DME patients after ineffective laserphotocoagulation or as an initial treatment. Best corrected visual acuity (BCVA) for distant and near vision, central retinal thickness and intraocular pressure (IOP) were analyzed before and after the treatment at intervals of 1 week, 1 month, 3 months and 6 months. The measurements were continued in cases of repeated IVTA. RESULTS: Statistically significant improvements were observed in BCVA in near and distant vision, as well as a decrease in central retinal thickness after all time-intervals following IVTA. BCVA in distant vision was not significantly improved after repeated IVTA. IOP increases were observed 1 week, 1 and 3 months after IVTA, but not at 6 months after IVTA. No sight-threatening side effects of IVTA were observed. CONCLUSIONS: IVTA is useful in stabilizing DME progression, although its therapeutic effect may be timelimited.

Caspase-Dependent Apoptosis of Retinal Ganglion Cells During the Development of Diabetic Retinopathy.

Diabetic retinopathy constitutes the most frequent cause of vision loss in professionally active individuals. Progressive impairment of visual acuity results from massive fibrovascular proliferation involving the fundus of the eye, as well as from the apoptosis of the neuronal structures of the retina. The results of many clinical studies, both on experimental models and on human material, confirmed evident enhancement of this process in the course of diabetes. The programmed cell death of retinal ganglion cells predominantly occurs secondarily to caspase-dependent intracellular processes. This paper presents evidence for the considerable involvement of the caspase-dependent mechanism of apoptosis of retinal ganglion cells in the early stages of retinal changes associated with progressive impairment of visual acuity. The authors emphasize the necessity of comprehensive understanding of mechanisms that underlie the programmed death of neural cells in the eyes of patients with diabetes. This clinical problem becomes of vital importance in view of the constantly increasing incidence of diabetes and severe impairment associated with the disorders of carbohydrate metabolism. Identification of a key component involved in this process would enable attempts oriented at pharmacological blockade of apoptosis in the retinal ganglion cells of patients with diabetes.

The Dry Form of Age-Related Macular Degeneration (AMD): The Current Concepts of Pathogenesis and Prospects for Treatment.

Age-related macular degeneration (AMD) is a disease that causes varying degrees of blindness, which afflicts millions of adults in their later years. Preliminary changes occur during normal aging, but in some individuals the pathology leads to the development of AMD. The pathology seems to be a mixture of biochemical, cellular, and molecular events. Lipofuscinogenesis and early drusen genesis are in the early stages of AMD and their inhibition or reversal would dramatically increase the quality of vision in elderly people. The disease is characterized by abnormal extracellular deposits, known as drusen, which accumulate along the basal surface of the retinal pigmented epithelium RPE. Widespread drusen deposition is associated with retinal pigmented epithelial cell dysfunction and degeneration of the photoreceptors. Recent studies have shown that drusen contain a variety of immunomodulatory molecules, suggesting that the process of drusen formation involves local inflammatory events, including activation of the complement cascade. Molecular pathways involved in the etiology of this disease and the potential prospects of its treatment will be presented on the basis of the results of the current studies.

Application of optical coherence tomography in glaucoma suspect eyes.

PURPOSE: The aim of the study was to compare the optical coherence tomography (OCT) parameters of the optic nerve head (ONH) and retinal nerve fibre layer (RNFL) and to identify which measurements are best able to differentiate between normal and glaucoma suspect eyes. METHODS: The study included 27 eyes with ocular hypertension (OHT), 33 eyes with pre-perimetric glaucoma (PG), 30 perimetrically unaffected eyes of patients with glaucoma in the fellow eye (FE) and 58 eyes of age-matched normal volunteers. All subjects underwent a complete eye examination with standard automated perimetry, optic disc photography and OCT imaging. Peripapillary 'fast RNFL thickness scans' and 'fast optic disc scans' were performed with time-domain OCT. The ONH and RNFL parameters were compared among the four study groups. The ONH and RNFL parameters were examined alone and then combined via four linear discriminant functions (LDF): LDF 1, the optimal combination of ONH parameters; LDF 2, the optimal combination of RNFL parameters; LDF 3, the optimal combination of both ONH and RNFL parameters; and LDF 4, the optimal combination of the best 11 parameters. The areas under the receiver operating curves (AUC) and the sensitivity at fixed specificity of at least 80 and 95 per cent were calculated for single parameters and LDF combinations and then compared. The best 11 parameters were selected based on their AUC values. RESULTS: Comparative analysis of OCT parameters revealed statistically significant differences in all seven ONH parameters in both PG and FE groups (and only in one ONH measurement in the ocular hypertensive group) when compared with normal eyes. Most of the RNFL parameters demonstrated statistically significant differences in all of the study groups when compared with the control group. The max-min parameter (0.835), inferior quadrant (0.833) and average RNFL thickness (0.829) obtained the highest AUC values in the whole glaucoma suspect group. The rim area had the best diagnostic accuracy among the ONH parameters (AUC = 0.817). The AUC values of the four LDF were: 0.825 (LDF 1), 0.882 (LDF 2), 0.902 (LDF 3) and 0.888 (LDF 4). Statistically significant differences were found between the AUC values of the single best ONH and RNFL parameters and LDF 3 and LDF 4. CONCLUSIONS: In the present study, RNFL parameters presented with better discriminatory abilities than ONH parameters in the OHT and FE groups. The ONH parameters demonstrated better diagnostic precision in differentiating between PG and normal eyes. The average RNFL thickness, max-min parameter and inferior quadrant RNFL thickness had the best abilities among single OCT measurements for discriminating between glaucoma suspect (including all ocular hypertensive, PG and FE eyes) and normal eyes. The combination of RNFL parameters only or both ONH and RNFL parameters, using linear discriminant analysis, provided the best classification results, improving the diagnostic accuracy of the instrument.

[Effect of different shape and material of intraocular lens on posterior capsule opacification]. / Wplyw ksztaltu i materialu soczewki wewnatrzgalkowej na powstawanie przymglenia torebki tylnej.

In this paper we compare 4 groups of intraocular lenses: PMMA, silicone, hydrogel, acrylic and their influence on posterior capsule opacification is discussed. The possible clinical consequences of different shape in optic part of intraocular lens is also described. This article contains also a short presentation of posterior capsule opacification mechanism and intraocular lens materials biocompatibility in in-vivo and in-vitro experiments.

[Treatment of subretinal macular hemorrhages with intravitreous injections of tissue plasminogen activator and SF6 gas]. / Leczenie krwotoków podsiatkówkowych w plamce doszklistkowym podawaniem tkankowego aktywatora plazminogenu oraz gazu SF6.

PURPOSE: Of our retrospective study was the estimation of the efficacy of recombinant tissue plasminogen activator (tPA) and intravitreal injections of SF6 gas in cases of subretinal macular haemorrhages. MATERIAL AND METHODS: In 20 patients aged 23-83 years, the subretinal macular haemorrhages were diagnosed, due to senile macular degeneration (9), hypertension (3), myopic retinochoroidal degeneration (3), other retinal heredodegeneration (2), retinal macroaneurysm (2) and trauma (1). We injected the solution of recombinant tissue plasminogen activator--Actilise (Boehringer Ingelheim) into vitreous cavity of these eyes. After lowering IOP, the intravitreous injections of 0.5 ccm SF6 gas were done, and following 24 hours down head positioning were carried out. RESULTS: The initial visual acuity before treatment was: HM or CF, from less then 1 meter in most of our cases (12 patients). The after treatment visual acuity ranged CF from 2 meters to 0.7. The early treatment conditioned better acuity. Even in cases of delayed treatment, the diminishing of central visual scotoma could be awaited. CONCLUSIONS: The new method of treatment in cases with subretinal macular haemorrhages despite of its symptomatic characters seems to be helpful in restoring the central vision in some cases.

[Surgical treatment of giant retinal tear]. / Leczenie chirurgiczne otworów olbrzymich siatkówki.

PURPOSE: The purpose of the study was to evaluate anatomical and functional results of pars plana vitrectomy in giant retinal tears. MATERIALS AND METHODS: Ten eyes with giant retinal tears underwent pars plana vitrectomy. The time of observation after surgical intervention was 3 months to 2.5 years. RESULTS: Retinal reattachment was obtained in 9 eyes (90%). In one eye, despite second vitrectomy, there was no positive effect due to massive vitreo-retinal proliferation. CONCLUSIONS: Surgical treatment of giant retinal tear yields good anatomical and functional results. Rarely massive vitreo-retinal proliferation may cause the redetachment. Perfluorodecalin used during surgery facilitates unfolding and flattening of the retina.