Download Molecular identification and antifungal susceptibility of Aspergillus

Molecular identification and antifungal susceptibility of Aspergillus lentulus isolates
came from keratitis cases from India
László Kredics1, Nikolett Baranyi1, Sándor Kocsubé1, Anita Raghavan2, Venkatapathy
Narendran2, Csaba Vágvölgyi1, Kanesan Panneer Selvam3, Yendremban Randhir Babu
Singh2,4, Balázs Leitgeb5, János Varga1, Palanisamy Manikandan2
1
Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Közép fasor 52, H-6726
Szeged, Hungary
2
Aravind Eye Hospital and Postgraduate Institute of Ophthalmology, Avinashi road, Coimbatore 641 014,
Tamilnadu, India
3
M.R. Govt. Arts College, Mannargudi 614 001, Thiruvarur, Tamilnadu, India
4
Department of Microbiology, Dr. GRD College of Science, Coimbatore, Tamilnadu, India
Aspergillus strains are among the most common organisms causing fungal keratitis in tropical
and subtropical areas. The main risk factor for the infection is trauma by vegetable matter
during agricultural activities. Among Aspergillus species mainly A. flavus, A. terreus, A.
fumigatus and A. niger have been isolated from fungal keratitis cases. During this study, 14
Aspergillus strains isolated from keratitis cases in South India were examined. Based on
morphological studies, all isolates were classified to the A. fumigatus species. For the
molecular identification, part of the calmodulin gene was amplified and sequenced. As a
result, 12 isolates were identified as A. fumigatus, while two were found to belong to the A.
lentulus species. This is the first report on the identification of A. lentulus from eye infections.
A. lentulus has morphological characteristics indistinguishable from A. fumigatus. This
organism has been identified within clinical isolate collections in centers worldwide. A salient
phenotype of A. lentulus is its reduced susceptibility to multiple antifungal drugs. The Etest
method (BioMérieux SA, Lyon, France) for molds was used to determine the antifungal
susceptibility of the isolates to amphotericin B, fluconazole, itraconazole, voriconazole,
micafungin, anidulafungin and caspofungin in accordance with the manufacturer’s
instructions. Results obtained for these strains were in accordance with the quality control
ranges published previously for these isolates. Further investigation of the genetic variability
of the A. fumigatus and A. lentulus isolates by UP-PCR analysis is in progress.
This research was realized in the frames of TÁMOP 4.2.4. A/2-11-1-2012-0001 „National
Excellence Program – Elaborating and operating an inland student and researcher personal
support system convergence program”. The project was subsidized by the European Union
and co-financed by the European Social Fund. This work was also supported by OTKA grant Nos.
K84122 and K84077, and the Indian National Science Academy – Hungarian Academy of Sciences
bilateral joint project (contract number: SNK-49/2013).