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Genotypic analysis of Pseudomonas aeruginosa isolated from ocular infection
Satoshi Yamaguchi1, Takashi Suzuki2, Takeshi Kobayashi2
1Department of Ophthalmology, Ehime University, Graduate School of Medicine, Shitsukawa, Toon, Ehime 791-0295, Japan; ROHTO Pharmaceutical Co., Ltd., 1-8-1 Tatsumi-nishi, Ikuno-ku, Osaka 544-8666, Japan.
Abstract:
Pseudomonas aeruginosa is the causative pathogen of keratitis, conjunctivitis, and dacryocystitis. However little is known about their clinical epidemiology in Japan. In this study we investigated the genotypic characterization and serotype of P. aeruginosa isolates from ocular infections. Thirty-four clinical P. aeruginosa isolates were characterized according to infection type, the type III secretion system (TTSS), serotype, and multilocus sequence typing (MLST). We divided the isolates into four clinical infection types as follows: Contact lens (CL)-related keratitis (CL-keratitis; 15 isolates), non CL-related keratitis (non CL-keratitis; 8 isolates), conjunctivitis (7 isolates), and dacryocystitis (4 isolates). Regarding the TTSS classification and serotyping classification, no significant differences were found among the infection types. Two clusters (I, II) and three subclusters (A, B, C) were classified according to MLST. CL-keratitis isolates with exoU positivity were clustered in II-B, and conjunctivitis was clustered in cluster I. Some linkage was found between the genetic background and CL-keratitis or conjunctivitis.
Insights
Pseudomonas aeruginosa ocular infections in Japan were genotyped. Contact lens-related keratitis and conjunctivitis showed linkage to specific genetic clusters.
Area of Science:
- Ophthalmology
- Microbiology
- Genetics
Background:
- Pseudomonas aeruginosa is a significant cause of ocular infections like keratitis, conjunctivitis, and dacryocystitis.
- Limited data exists on the clinical epidemiology and genotypic characteristics of P. aeruginosa in Japan.
Purpose of the Study:
- To investigate the genotypic characterization and serotypes of P. aeruginosa isolates from ocular infections in Japan.
- To explore potential links between genetic background and specific ocular infection types.
Main Methods:
- Thirty-four clinical P. aeruginosa isolates were analyzed.
- Characterization included infection type, type III secretion system (TTSS) presence, serotyping, and multilocus sequence typing (MLST).
- Isolates were categorized into contact lens-related keratitis (CL-keratitis), non-CL keratitis, conjunctivitis, and dacryocystitis.
Main Results:
- No significant differences in TTSS or serotype classifications were observed across different infection types.
- MLST analysis revealed two main clusters (I, II) and three subclusters (A, B, C).
- CL-keratitis isolates positive for exoU were found in cluster II-B, while conjunctivitis isolates were predominantly in cluster I, suggesting a genetic linkage.
Conclusions:
- A correlation was identified between the genetic background of P. aeruginosa and specific ocular infections, namely CL-keratitis and conjunctivitis.
- This study provides insights into the molecular epidemiology of P. aeruginosa in Japanese ocular infections.
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