Sensitive and rapid polymerase chain reaction based diagnosis of mycotic keratitis through single stranded conformation polymorphism.
OBJECTIVE
To report a method for early and correct diagnosis of mycotic keratitis.


METHODS
Clinical laboratory diagnostic study.


METHODS
Corneal scraping of all the four patients were processed for DNA extraction which were amplified by fungal specific primers of internal transcribed spacer region I (ITS1). These products were sequenced and analyzed by single stranded conformation polymorphism (SSCP) for species identification.


RESULTS
The DNA samples from corneal scrapings of all the four patients were successfully amplified by the primer pair ITS1 and ITS2 and similarity/dissimilarity were established by Jaccard's coefficient. Patient isolate 1 was identified as Nectria hematococca, isolate 2 as Candida albicans, and isolates 3 and 4 were identified as Bipolaris papendorfii. This led to prompt initiation of antifungal therapy in all the four cases where useful vision could be restored.


CONCLUSIONS
Early and correct diagnosis of mycotic keratitis by polymerase chain reaction could be obtained in all the four cases compared with conventional methods, which helped in the prompt initiation of antifungal therapy in patients.
Kumar
Manish
M
Division of Fermentation Technology, Central Drug Research Institute, M.G. Marg, Lucknow, India.
Mishra
Nisha Kant
NK
Shukla
Praveen K
PK
D000293:Adolescent; D000328:Adult; D000368:Aged; D000935:Antifungal Agents / Q000627:therapeutic use; D001203:Ascomycota / Q000235:genetics / Q000302:isolation & purification; D001483:Base Sequence; D002175:Candida / Q000235:genetics / Q000302:isolation & purification; D003315:Cornea / Q000187:drug effects / Q000382:microbiology*; D003320:Corneal Ulcer / Q000188:drug therapy / Q000382:microbiology*; D004271:DNA, Fungal / Q000032:analysis; D015821:Eye Infections, Fungal / Q000188:drug therapy / Q000382:microbiology*; D005260:Female; D005658:Fungi / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008297:Male; D008969:Molecular Sequence Data; D016533:Mycological Typing Techniques; D009181:Mycoses / Q000188:drug therapy / Q000382:microbiology*; D016133:Polymerase Chain Reaction / Q000379:methods*; D018807:Polymorphism, Single-Stranded Conformational; D012680:Sensitivity and Specificity; D012689:Sequence Homology, Nucleic Acid
D000935:Antifungal Agents; D004271:DNA, Fungal