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To determine the safety and efficacy of black tea extract in the treatment of bacterial conjunctivitis in a rabbit model and compare it with that of gatifloxacin drops. Methods: Black tea extract was tested in vitro on bacterial cultures of methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa. Forty-two rabbit eyes were cultured with either MRSA (n¼21) or P. aeruginosa (n¼21) and further divided into a control group (n¼5), a tea group (n¼8) treated with black tea extract, and a gatifloxacin group (n¼8) treated with 0.3% gatifloxacin eye drops. Conjunctival swabs were collected on the third and fifth days. Results: The tea extract successfully inhibited the growth of both organisms at a concentration of 400 mg/mL. Rabbits in the treatment groups showed a reduction in the clinical index on day 2 (P,0.01), unlike the control group (P¼0.1), for both organisms. Resolution of conjunctivitis was achieved on days 4 and 5 in the tea and gatifloxacin groups, respectively. On days 3 and 5, while the control group still showed considerable bacterial growth, the tea and gatifloxacin groups showed its inhibition. Conclusion: Tea extract has antimicrobial effects similar to those of gatifloxacin in a rabbit model of conjunctivitis.

Background PACK-CXL (photo-activated chromophore for keratitis–corneal cross-linking) is an alternative option in treatment of corneal infections. It inhibits corneal melting by increasing the stromal resistance, besides the microbicidal effect of photo-activated riboflavin. Methods Corneal infection with Pseudomonas aeruginosa and Staph aureus bacteria was induced in 20 eyes of 10 rabbits after 6 weeks of corneal cross-linking in half of the eyes, while the other acted as control group. Clinical and corneal histopathological examination was done to evaluate the extent of inflammation, ulceration, organism penetration, and depth of corneal stromal affection. Results The control eyes developed severe inflammation compared to the cross-linked eyes. Corneal melting occurred in 6 eyes in the control versus none in cross-linked group. Histopathological examination showed that the inflammation was confined to the superficial part of the stroma with localization of the inflammation in the cross-linked eyes in contrast to the control eyes that showed deep infiltration. Conclusion PACK-CXL provides infection localization through increasing the corneal rigidity and resistance to enzymatic digestion, even in the absence of the riboflavin microbicidal role. So, early PACK-CXL is worth to be considered in the IK treatment algorithm.

Background: The relation between the kidney disease and the eye has always been a subject of interest, their anatomical, developmental and genetic similarity, suggests the link between the kidney and eye diseases, also they share the same predisposing factors like diabetes, hypertension, oxidative stress and smoking. Chronic kidney disease is one of the known causes of retinopathyPurpose: To evaluate the effect of duration of longterm hemodialysis in chronic kidney disease (CKD) patients on the macular and optic nerve vasculature using optical coherence tomography angiography (OCTA). Methods: This cross-sectional observational study included 36 eyes of 36 patients with CKD on longterm hemodialysis of different durations of onset. We correlated the vessel density in the macula in the superficial capillary plexus (SCP) and deep capillary plexus (DCP) and optic nerve head in the radial peripapillary capillary plexus (RPC) using OCTA to the duration of onset of longterm hemodialysis in these patients and to their laboratory findings as urea reduction ratio, urea level, creatinine and blood pressure.Results: Mean duration of hemodialysis was 6.11± 2.93 years. A negative correlation between the duration of hemodialysis and vessel density of the macular SCP and DCP and optic nerve head RPC, with statistical significance in SCP in PeriFoveal section (p, 0.045), RPC Inside Disc (p, 0.022) and in the RPC average Peripapillary area (p, 0.049). The correlation between the vessel density and the URR was positive, and with statistical significance in the SCP in PeriFoveal section, RPC average Peripapillary and Inside disc vessel density but a negative correlation has been found between the URR and the DCP Parafoveal section with no statistical significance.Conclusion: The macular SCP and DCP vessel density and optic nerve head RPC vessel density decrease with increase in the duration of longterm hemodialysis in chronic kidney disease (CKD) patients.