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Detection of Streptococcus species by polymerase chain reaction in infectious crystalline keratopathy
Yasuhiro Osakabe1, Chiemi Yaguchi, Takashi Miyai
1Meiwakai Medical Foundation, Miyata Eye Hospital, Miyakonojo, Miyazaki, Japan.
Purpose:
Investigation of a positive polymerase chain reaction (PCR) for Streptococcus species from an excised cornea of a patient with infectious crystalline keratopathy.
Methods:
Samples microdissected from corneal intrastromal aggregates present in infectious crystalline keratopathy were subjected to PCR for 3 primer pairs respectively specific for Streptococcus, Staphylococcus, and several kinds of fungi.
Results:
The PCR detected DNA from Streptococcus but not from Staphylococcus or fungi. Direct sequencing of the PCR products showed that the PCR products had the highest identity (99.8%) with Streptococcus mitis and Streptococcus gordoni, indicating that these species were the most probable causes of infectious crystalline keratopathy in this patient.
Conclusion:
Our findings suggest that PCR provides a good adjunct technique in the diagnosis of corneal infection.
Insights
Polymerase chain reaction (PCR) detected Streptococcus species, likely Streptococcus mitis and Streptococcus gordoni, in a patient with infectious crystalline keratopathy. This molecular method aids in diagnosing corneal infections.
Area of Science:
- Ophthalmology
- Microbiology
- Molecular Diagnostics
Background:
- Infectious crystalline keratopathy (ICK) is a severe corneal infection.
- Accurate and rapid diagnosis is crucial for effective treatment.
- Traditional diagnostic methods may have limitations in identifying specific pathogens.
Observation:
- A patient presented with infectious crystalline keratopathy.
- Samples from the corneal intrastromal aggregates were analyzed.
- Polymerase chain reaction (PCR) was employed using specific primers.
Findings:
- PCR successfully detected Streptococcus DNA in the corneal samples.
- No Staphylococcus or fungal DNA was identified.
- Direct sequencing revealed high identity with Streptococcus mitis and Streptococcus gordoni.
Implications:
- PCR is a valuable adjunct diagnostic tool for corneal infections.
- Identifies specific bacterial species contributing to ICK.
- Facilitates targeted antimicrobial therapy for better patient outcomes.
