Here, we report, to our knowledge, the largest case study of human pythiosis. The disease has high rates of morbidity and mortality. Early diagnosis and effective treatment are urgently needed to improve clinical outcomes. Because P. insidiosum is distributed worldwide and can infect healthy individuals, an awareness of human pythiosis should be promoted in Thailand and in other countries.

There was a trend toward improvement in symptoms and signs of dry eye including cytologic changes after application of autologous serum in severe dry eye patients. However, this trend was not statistically significant. A larger scale study is warranted.

Pythium insidiosum is a pathogen that causes disease in both animals and humans. Human infection is rare; however, when it does occur, most patients, especially those having underlying hemoglobinopathy syndromes, such as thalassemia, exhibit a severe form. We identified four isolates of P. insidiosum. Two were recovered from tissue biopsy specimens from thalassemic and leukemic patients, one was derived from brain tissue from a thalassemic patient, and another was isolated from a corneal ulcer from a fourth patient. Western blotting and an enzyme-linked immunosorbent assay (ELISA) were performed with a serum sample derived from one thalassemic patient. The methods used to identify the P. insidiosum isolates were based on morphology, nucleic acid sequencing, and a PCR assay. To confirm the identification, portions of the 18S rRNA genes of these four isolates were sequenced. The sequences were shown to be homologous to previously described P. insidiosum DNA sequences. In addition, PCR amplification of the internal transcribed spacer region specific for P. insidiosum was positive for all four isolates. The ELISA with the serum sample from the thalassemic patient gave a positive result from a serum dilution of 1:800. Finally, Western immunoblotting with this serum sample showed positive immunoglobulin G recognition for proteins of 110, 73, 56, 42 to 35, 30 to 28, 26, and 23 kDa. The results of this study show that both molecularly based diagnostic and serodiagnostic techniques are useful for the rapid identification of human pythiosis. The predominant antigens recognized by Western blotting may be useful in the development of a more sensitive and specific diagnostic tool for this disease.

The surgical results of primary pterygium excision followed by amniotic membrane and conjunctival autograft transplantation were compared. It was found that amniotic membrane transplantation for pterygium surgery has an unacceptably high recurrence rate.

Aims To assess the possible role of virus infection in patients with unexplained anterior uveitis (AU). Methods Intraocular fluid and plasma samples of 30 HIV-negative AU patients who were unresponsive or poorly responsive to topical steroid therapy were analyzed for nucleic acid of cytomegalovirus (CMV), herpes simplex virus (HSV), and varicella zoster virus (VZV) by realtime polymerase chain reaction (PCR) and for intraocular antibodies against these viruses by Goldmann-Witmer coefficient (GWC) analysis. Of these 30 cases, 21 were tested for rubella virus by GWC analysis, 16 of which also had PCR assessment of aqueous for rubella virus. Results Viral uveitis determined by either real-time PCR and/or GWC was documented in 20 out of 30 patients (67%). Of 30 paired samples tested by both methods for HSV, CMV, and VZV, 15 showed positive results (CMV (10), HSV (4), and VZV (1)). Real-time PCR was positive in 8/15 (53%), whereas GWC was positive in 10/15 (67%). Out of 10 CMV-positive patients, four had endotheliitis, two had Posner-Schlossman syndrome, and one Fuchs heterochromic uveitis syndrome (FHUS). Five out of 21 (24%) samples tested by GWC for Rubella virus were positive, three of which exhibited clinical features of FHUS. Conclusions Our results indicate that CMV is a major cause of AU in Thailand and show that FHUS can be caused by both CMV and Rubella virus.

This study shows that impression cytology might have a promising role in diagnosing ocular surface neoplasia for its high positive predictive accuracy compared with tissue histology. However, a fair negative predictive accuracy indicates that impression cytology is a valuable screening technique, but it is not a "gold standard."

Purpose The PCR was compared with routine microbial studies for the detection of fungal pathogens in clinically suspected fungal keratitis. Methods A prospective nonrandomized study was undertaken at a tertiary eye care centre to evaluate 30 eyes of 30 patients with presumed fungal keratitis, both fresh and treated. Corneal scrapings were performed on each patient. The specimens were analysed by a semi-nested PCR assay using fungalspecific primers. PCR products were cloned and sequenced for identification, and compared with a conventional microbial work-up (smear and culture). Results Of the 30 samples, the PCR showed positivity in 93.3%, culture in 40%, and potassium hydroxide in 20%. Of the 28 PCR-positive cases, 12 were culture-positive and 16 were culture-negative. Two samples were both PCR and culture test negative. Culture-negative samples were PCR-positive in 16 of 18 (88.9%) cases. The PCR did not yield any false-negative findings in a culturepositive specimen. Both common and uncommon aetiologic fungi have been identified by DNA sequencing analysis. Conclusion The PCR was able to detect fungal DNA in a high proportion of culturenegative cases. Technical considerations of the PCR process include extraction of artifacts and amplification of non-pathogenic DNA. Nonetheless, our findings suggest that the PCR can be a useful adjunct to smear and culture in the rapid diagnosis of fungal keratitis, particularly in cases of failed detection from routine procedures.

Background: This study aimed to determine the influence of age on central corneal thickness and corneal endothelial morphology as well as to identify the relationship between them in normal Thai eyes. Methods: Non-contact specular microscopy was performed in volunteers stratified into seven age groups ranging from 11 to 88 years. The corneal endothelial parameters studied included central corneal thickness (CCT), endothelial cell density (ECD), coefficient of variation in cell size (CV), cell area (CA) and percentage of regular hexagonal cells. Results: In a total of 501 subjects (1002 eyes), the mean age was 43.12 ± 18.80 years and 347(69.3%) were females. The mean CCT, ECD, CV, CA, and hexagonality was 533.80 ± 33.00 μm, 2732 ± 258 cell/mm 2 , 37.61 ± 6.76%, 369.04 ± 37.90 μm, and 49.03 ± 7.53%, respectively. There was a significant inverse correlation between age and CCT (r = − 0.215, P < 0.001), ECD (r = − 0.496, P < 0.001),and hexagonality (r = − 0.265, P < 0.001). The CV and CA directly correlated with age (r = 0.242, P < 0.001 and r = 0.470, P < 0.001). The estimate rate of endothelial cell loss was 0.2% per year. There was no correlation between CCT and ECD (P = 0.106). Conclusion: Normative data for corneal endothelial morphology in healthy Thai eyes showed that CCT, ECD, and hexagonality were significantly decreased, while the endothelial cell area and the variation in cell size were increased with aging. The central corneal thickness did not correlate with the endothelial cell density.