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OBJECTIVE:To determine the conjunctival bacterial flora present in patients with Stevens-Johnson syndrome.METHODS:A prospective study of the conjunctival bacterial flora was performed in 41 eyes of 22 patients with Stevens-Johnson syndrome. The information gathered included the patient's sex and age, the duration of disease, the cause of Stevens-Johnson syndrome, and treatments. Scrapings of the inferior conjunctival fornix were performed in both eyes. Fourteen days before scraping, the patients were asked to interrupt all topical medication and start using 0.5% nonpreserved methylcellulose. The microbiological evaluation included microorganism identification and determination of antibiotic sensitivity.RESULTS:Of 22 patients (41 eyes), 14 (64%) were females, and eight (36%) were males. The mean age was 33.2 years, and the mean duration of disease was 15.6 years. Visual acuity ranged from light perception to 20/25 (1.57 logMar). The treatment received by most patients consisted of tear substitutes, topical antibiotics, and contact lenses. Bacterial identification was positive in 39 eyes (95%) and negative in two eyes (5%). Gram-positive cocci accounted for 55.5% of the microorganisms, whereas gram-positive bacilli and gram-negative bacilli accounted for 19% and 25.5%, respectively.Half of the patients (54%) had multiple bacterial species in their flora, and only one bacterial species was identified in the other half. Resistant bacteria were isolated from four eyes. The antibiotic sensitivity results for the Streptococcus group showed the lowest sensitivity and the highest microbial resistance identified.CONCLUSION:Patients with Stevens-Johnson syndrome have a diverse conjunctival flora that includes many pathogenic species.

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Bacterioplankton was studied in a large area of Southwest Atlantic Ocean between 13 and 25ºS and 28 and 42ºW. Samples were collected in 108 stations at 20 m depth. Bacteria were enumerated by flow cytometry after nucleic acid staining with syto13 and two subgroups were differentiated: low nucleic acid content (LNA) and high nucleic acid content (HNA) bacteria. Total bacterial numbers varied from 0.37 to 5.53 10 5 cells mL -1. HNA cells represented 15 to 70% of the total number while LNA cells represented 30 to 85%. Heterotrophic bacterial production was determined by incorporation of tritiated leucine and ranged from 2.7 to 171.07 ng C L -1 h -1. No significant correlation was found between abundance and production. Nevertheless with support of multivariate analysis between bacterial abundance, bacterial production, chlorophyll a and other oceanographic data the distribution of the groups in two different oceanic provinces could be explained by nutrient availability. HNA bacteria accounted for the high percentage of cells found in the area north of 19ºS, linked to higher temperature waters and riverine nutrients inputs. LNA bacteria were the dominant cells south of this latitude and were correlated to the higher values of nitrate found for the same area.

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