Effective and selective prevention of retinal leukostasis in streptozotocin-induced diabetic rats using gliclazide.

AIMS/HYPOTHESIS: Early stage leukocyte entrapment in the retinal microcirculation (retinal leukostasis) is considered to be one of the important pathogenetic events in diabetic retinopathy. Gliclazide, a sulphonylurea, was reported to reduce leukocyte adhesion to endothelial cells in hyperglycaemia in vitro, thus suggesting possible selective efficacy of this sulphonylurea in preventing leukostasis in diabetic patients. This study evaluated the effectiveness and selectivity of gliclazide treatment on retinal leukostasis of diabetic rats in vivo. METHODS: Streptozotocin (STZ) (65 mg/kg)-induced diabetic rats were divided into three groups (n = 8 each): an untreated diabetic group, a gliclazide-treated diabetic group, and a glibenclamide-treated diabetic group. Gliclazide or glibenclamide was administered orally during a 3-week period. Non-diabetic rats were used as a control (n = 8). Retinal leukostasis was quantitatively evaluated in vivo by acridine orange leukocyte fluorography using a scanning laser ophthalmoscope. RESULTS: The number of leukocytes trapped in the area around the optic disc in the untreated diabetic group (36.9 +/- 5.1 cells) increased significantly compared with the non-diabetic control group (21.9 +/- 2.9 cells; p = 0.0007). The number of leukocytes trapped in the gliclazide-treated diabetic group (23.5 +/- 4.0 cells) decreased significantly compared with untreated diabetic group ( p = 0.0008). In contrast, no reduction of retinal leukostasis was found in the glibenclamide-treated diabetic group (37.8 +/- 5.8 cells; p = 0.7923). CONCLUSION/INTERPRETATION: This suggests that gliclazide could directly improve abnormalities in the retinal microcirculation independent of blood glucose control and possibly have selective therapeutic benefits in preventing early, critical events in diabetic retinopathy compared with other sulphonylurea drugs.

Stromal keratitis and anterior uveitis due to herpes simplex virus-2 in a young child.

BACKGROUND: An uncommon case of stromal keratitis and anterior uveitis due to herpes simplex virus type 2 (HSV-2) is reported. CASE: The patient was a 3-year-old boy admitted for conjunctival injection of the right eye of unknown cause, accompanied by corneal opacity and anterior uveitis. OBSERVATIONS: High titers of antibodies against HSV and Epstein-Barr virus (EBV) were found in blood samples. Polymerase chain reaction (PCR) for the detection of HSV-1, -2, and EBV genome fragments was carried out using an anterior chamber sample as a template. An HSV-2 genome fragment was amplified by PCR. Administration of acyclovir and betamethasone was started, with the consequent elimination of corneal opacity, inflammatory cells, and keratic precipitates. CONCLUSION: PCR clearly showed that HSV-2 was the causative pathogen of the stromal keratitis and anterior uveitis in this young patient. Systemic EVB infection may induce systemic immunocompromised conditions that can lead to reactivation of HSV-2 followed by ocular disorders.

[Results of vitreous surgery for idiopathic macular holes and retinal sensitivity].

We evaluated the visual outcome in 16 eyes with idiopathic full-thickness macular holes. Phacoemulsification and posterior chamber intraocular lens implantation was also performed, if cataract was present. Closure of the macular hole was obtained in 12 eyes, 75%. Postoperative visual acuity improved by 2 lines or more in 14 eyes, (87.5%), 0.5 or better in 9 eyes, (56.2%), and 0.8 or better in 6 eyes, 37.5%. The correlation values between postoperative visual acuity and size of hole, % decrease of macular retinal sensitivity, macular retinal sensitivity, preoperative visual acuity, size of fluid cuff, and duration were -0.766, 0.710, 0.696, 0.676, -0.665, and -0.313, respectively. Measurement of macular retinal sensitivity with macular hole size could be very useful for predicting postoperative visual acuity.