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Specimens of bacterial ocular infections are frequently received in the clinical laboratory. However, a comprehensive trend survey of ocular infections with bacteria is very rare. Our objective is to understand the current tendency of ocular infections with bacteria in patients at Toyama University Hospital from the standpoint of laboratory examination. We studied 263 cases of ocular infection with bacteria diagnosed at Toyama University Hospital from January 2006 to December 2011. 123 were male and 140 were female, with a mean age of 61.2(0-98) years. Specimens were subjected to direct microscopy and culture. Cultures were positive in 174(66.2%) patients. The most common bacterial isolate was Staphylococcus (28.1%), followed by Corynebacterium (19.3%), Streptococcus (9.3%), and Propionibacterium (8.6%). MRSA accounted for 18.8% of all S. aureus isolates, and has increased in recent years. The number of bacteria detected was larger in March, June, July, August, and October. Age distribution indicated that around 70% of bacterial isolates were detected from patients over 60 years old. The most common specimen of ocular infections with bacteria was eye discharge (detection rate; 87.8%), followed by corneal scraping(41%), aqueous humor (19%), and vitreous body (27%). Nearly 80% of bacterial isolates were detected from patients with keratitis, endophthalmitis, dacryocystitis, and conjunctivitis. As for the disease specific detection rate, endophthalmitis was very low (38.3%). The detection rate by years indicated that the way doctors pick up the specimens greatly affects the detection rate. Based on this survey, we need close cooperation with medical doctors concerning laboratory examination in ocular infection with bacteria, and we must improve the detection sensitivity of specimens from patients with endophthalmitis.

Cysts of 2 isolates of Acanthamoeba from the cornea of 2 patients with confirmed Acanthamoeba keratitis were tested in vitro for sensitivity to antimycotic agents such as fluconazole, miconazole, amphotericin-B, pimaricin, antiprotozoal agents such as pentamidine isetionate and antiseptics which could be use in the ophthamological region. Pimaricin was the most successful cysticidal agent against the two strains. Sensitivity to pentamidine isetionate showed variation. Fluconazole, miconazole and amphotericin-B were resistant against cysts with concentration of eye drops that have been used in the treatment of Acanthamoeba keratitis. It was supposed that 5% pimaricin eye drops could be use in the treatment of Acanthamoeba keratitis in addition to keratomycosis. Pentamidine isetionate which belong to the diamidine family, is not yet clear as to the side effects to corneal epithelium cell, but we believe that this drug could be expected as a new therapeutic agent for Acanthamoeba keratitis.

In the present study, we tried to detect the tissue of origin of herpes simplex virus type 1 (HSV-1) reactivated in tear film after artificial reactivation. The combined treatment consisted of iontophoresis on postinoculation day 35, followed by topical epinephrine on 2 days, after which the rabbits were killed. The ocular tissues and trigeminal ganglia were immediately dissected. Their cell-free supernatants were inoculated on CV-1 (African green monkey kidney cell) monolayers for infectious HSV-1 detection. The percentage of recovery from the cell-free supernatants was 50% (5 out of 10 samples) from the cornea, 0% from conjunctiva or lacrimal glands, and 20% (2 out of 10 samples) from trigeminal ganglia. The percentage of HSV-1 reactivation in the tear film was 50%. No infectious virus was detected from tissues or tear film in the control group. Four eyes showed HSV-1 reactivation simultaneously from the cornea and tear film, but only one eye from the trigeminal ganglion and tear film. These results demonstrate that the cornea might be the tissue of origin of HSV-1 reactivated in tear film.

We tried to identify herpes simplex virus type 1 (HSV-1) latency in the cornea obtained at the time of penetrating keratoplasty from patients with herpetic stromal keratitis in the non-active (subsided) stage. The subject consisted of 8 patients (3 males and 5 females; average age 42.3 years) who were diagnosed as having herpetic stromal keratitis and underwent penetrating keratoplasty during a period without active lesions (subsided stage) between August, 1984 and July, 1988. No infective virus was detected in the centrifugation supernatant following each corneal homogenization. Latent virus was detected from the culture supernatant of sections of the corneas in 4 of the 8 patients. Although the ganglion trigger theory of Hill et al. has been conventionally supported as the mechanism(s) of herpetic keratitis recurrence, our results suggest that HSV-1 proliferation from latency in the cornea (peripheral tissue) might stimulate the ganglion (ganglion and skin trigger theory). The present study is the first to demonstrate HSV-1 latency in the cornea.

Adherence of bacteria to the corneal epithelium is the first step in the pathogenesis of corneal infection. Keratitis caused by Pseudomonas aeruginosa usually occurs among the contact lens wearers. Adherence of Pseudomonas aeruginosa to rabbit corneal epithelium, damaged by one week of hard contact lens wear, was examined histologically. The cornea was excised for scanning electron microscopy at 5, 15, 30 and 60 minutes after inoculation of Pseudomonas aeruginosa (0.2 ml, 10(8)CFU/ml). Pseudomonas aeruginosa did not adhere to the intact corneal epithelium, but traumatized cornea provided a site for adherence. In rabbits in which the eyelid was opened by lid retractors, large numbers of organisms were observed adhering to the injured cornea mediated by ocular surface mucin. Thirty minutes after inoculation, the adherent bacteria began to penetrate the epithelial cells and surface mucin by the formation of pockets surrounding the organism.

Changes in localization of virus-associated antigens induced by F3TdR were studied using HSV-1 infected monolayer of cultured SIRC cells. A direct enzyme-antibody method was employed for preembedding for immunoelectron and light microscopy. At 3 hours post infection (h.p.i.), immunoreaction products began to appear in cytoplasm and nuclei in both the control and the F3TdR-treated group. The amounts increased during the subsequent hours of observation. In the control group, there was an intense diffuse immunoreaction in the cytoplasm and nuclei and dense accumulations of the reaction products were seen on the cell surfaces. In F3TdR-treated cells, intranuclear antigens were present as diffuse accumulations of granular deposits, and cytoplasmic stainings were very much reduced in degree; deposits on the cell surface were a rare finding. Progeny virus particles were significantly fewer in the presence of F3TdR; nucleocapsids were found but in a greatly reduced number and no enveloped particle was found. The morphology of individual nucleocapsid, however, was not significantly altered by treatment with F3TdR. A preponderance of antigenic substances in the nuclei over the cytoplasm in treatment group may reflect distorted protein synthesis and may provide morphological evidence of the biochemically assumed hypothesis of F3TdR efficacy; F3TdR exerts it's antiviral effects through abnormal protein synthesis and resultant defects in capsid assembly. Decreased antigenic substances in the membranous structures of cytoplasm may be related to reduced or abnormal production of viral antigens closely associated with envelopment.