Vision impairment in the Pacific region

The Western Pacific region is one of great diversity, containing the most populous country, China, and many small Pacific island countries. This review describes the prevalence of blindness and vision loss, illustrates the changing trends in the important causes of vision loss and blindness, and the stages of development of the delivery of eye care services across this region.

A simplified cataract grading system

A simplified method for grading the presence and severity of different cataract types is needed for field use in assessment of the magnitude of the cataract problem. A cataract grading system was developed by a panel of experts with the objective of making available a simple system for use with a slit lamp to allow for the reliable grading of the most common forms of cataract by relatively inexperienced observers. Three levels, reflecting progressive severity, for grading of nuclear, cortical and posterior subcapsular (PSC) cataract were included in the classification; three standard photos were used for grading nuclear cataract. Field evaluation from four different sites indicated very good to fair interobserver agreement with the use of this system following minimal training of residents in ophthalmology at each site. Further testing of this system is warranted. The WHO simplified cataract grading system should allow for the obtaining of comparable data across countries based on field assessment of the most common forms of cataract.

Serotyping of Cryptococcus neoformans strains isolated from clinical specimens in Thailand and their susceptibility to various antifungal agents

One hundred and thirty-nine strains of Cryptococcus neoformans were isolated in Thailand from clinical specimens including 97 AIDS patients: 67 from Northern, 48 from Central, 17 from Northeastern and 7 from Southern regional hospitals. Six out of the 139 strains were serotype B and the remaining 133 were A. There was no correlation between serotypes and regional distribution. To our knowledge, this is the first report of serotyping studies on C. neoformans in Thailand. Studies on random amplified polymorphic DNA (RAPD) analysis showed that this method is useful for the differentiation of C. neoformans var. gattii (serotypes B and C) and C. neoformans var. neoformans (serotypes A and D). They also indicated that Thai isolates of C. neoformans var. gattii (serotype B) were a homogeneous group on the basis of their genotypes. Antifungal susceptibility tests using 5 antifungal agents including amphotericin B, fluconazole, flucytosine, itraconazole and micronazole against 50 selected strains of C. neoformans showed that they were sensitive to all of the antifungal agents tested except for one strain that was resistant to flucytosine.

In vitro antifungal activity of the new triazole D0870 against Penicillium marneffei compared with that of amphotericin B, fluconazole, itraconazole, miconazole and flucytosine

The in vitro activity of D0870, a new triazole, was compared with that of fluconazole, itraconazole, miconazole, amphotericin B and flucytosine against recent clinical isolates of Penicillium marneffei in Thailand. The minimum inhibitory concentrations (MIC) values were determined by a microbroth dilution method using morpholinopropanesulphonic acid (MOPS)-buffered RPMI-1640 and brain heart infusion (BHI) medium. Yeast nitrogen base (YNB) medium with glucose was also used for the assay of flucytosine. D0870 was less active against P. marneffei than itraconazole, but its activity was similar to that of miconazole, superior to that of amphotericin B and markedly superior to that of fluconazole and flucytosine. Much lower MIC values of D0870 were observed with BHI medium.

Pathogenic Nocardia isolated from clinical specimens including those of AIDS patients in Thailand

Forty strains of nocardioform microorganisms were isolated as clinical specimens including several from AIDS patients in Thailand. Among them, 37 strains were found to belong to the genus Nocardia. Our identification studies revealed that most of the strains (25 strains) belong to the N. asteroides group, i.e., N. asteroides sensu stricto and N. farcinica. Three strains were identified as N. otitidiscaviarum and two strains N. brasiliensis. In addition, 7 strains of rare pathogenic N. transvalensis were also isolated.