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The use of in vivo confocal microscopy to track treatment success in fungal keratitis and to differentiate between Fusarium and Aspergillus keratitis

  • Seyed Ali Tabatabaei
  • Mohammad SoleimaniEmail author
  • Seyed Mehdi Tabatabaei
  • Amir Houshang Beheshtnejad
  • Niloufar Valipour
  • Shahram Mahmoudi
Original Paper
  • 25 Downloads

Abstract

Purpose

To evaluate the usefulness of serial in vivo confocal microscopy (IVCM) examinations to measure hyphal density for monitoring the treatment success among patients with fungal keratitis, and to compare the hyphal diameter as well as branching angle as a way of differentiation between Aspergillus and Fusarium species observed in IVCM.

Study design

Prospective nonrandomized study.

Patients and methods

The study was conducted from February 2015 to September 2016. Hyphal diameter, density and branching angle measurements were performed using IVCM at admission and on a weekly basis for at least 2 weeks after the start of treatment.

Results

During the period of study, 65 patients with culture-confirmed fungal keratitis were recruited. Of them, 40 were culture-positive for Fusarium spp. and 25 patients for Aspergillus spp. Before the start of treatment, the mean branching angle did not differ between the two species and the mean hyphal diameter was statistically higher for Aspergillus spp. (p = 0.029). Two weeks after the start of treatment, the mean hyphal diameter was statistically lower (p < 0.001) in the treatment failure group. Also the hyphal density significantly decreased with successful treatment (p < 0.05).

Conclusion

Decreasing hyphal density in serial IVCMs might be used as an indicator to predict the successful response of fungal ulcers to treatment. Branching angle is not different between Aspergillus and Fusarium keratitis. The mean hyphal diameter is significantly lower in the treatment failure group.

Keywords

Fungal keratitis Fusarium Aspergillus In vivo confocal microscopy Diagnosis Keratitis 

Notes

Acknowledgements

The authors should thank Mrs. Kasiri and Dr. Abedini because of their effort in obtaining confocal sequence imaging and microbiologic assessment, respectively.

Funding

None.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

All procedures performed in this study were in accordance with the ethical standards of the institutional and with the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards.

Informed consent

Informed consent was obtained from all individual participants included in the study.

References

  1. 1.
    Takezawa Y, Shiraishi A, Noda E et al (2010) Effectiveness of in vivo confocal microscopy in detecting filamentous fungi during clinical course of fungal keratitis. Cornea 29(12):1346–1352CrossRefGoogle Scholar
  2. 2.
    Chidambaram JD, Prajna NV, Larke N, Macleod D, Srikanthi P, Lanjewar S (2017) In vivo confocal microscopy appearance of Fusarium and Aspergillus species in fungal keratitis. Br J Ophthalmol 101(8):1119–1123CrossRefGoogle Scholar
  3. 3.
    Iyer SA, Tuli SS, Wagoner RC (2006) Fungal keratitis: emerging trends and treatment outcomes. Eye Contact Lens 32:267–271CrossRefGoogle Scholar
  4. 4.
    Shukla PK, Kumar M, Keshava GB (2008) Mycotic keratitis: an overview of diagnosis and therapy. Mycoses 51(3):183–199CrossRefGoogle Scholar
  5. 5.
    Sun CQ, Lalitha P, Prajna NV et al (2014) Association between in vitro susceptibility to natamycin and voriconazole and clinical outcomes in fungal keratitis. Ophthalmology 121(8):1495–1500CrossRefGoogle Scholar
  6. 6.
    Mahmoudi S, Masoomi A, Ahmadikia K et al (2018) Fungal keratitis: an overview of clinical and laboratory aspects. Mycoses 61(12):916–930.  https://doi.org/10.1111/myc.12822 CrossRefPubMedGoogle Scholar
  7. 7.
    Winchester K, Mathers WD, Sutphin JE (1997) Diagnosis of Aspergillus keratitis in vivo with confocal microscopy. Cornea 16(1):27–31CrossRefGoogle Scholar
  8. 8.
    Avunduk AM, Beuerman RW, Varnell ED, Kaufman HE (2003) Confocal microscopy of Aspergillus fumigatus keratitis. Br J Ophthalmol 87(4):409–410CrossRefGoogle Scholar
  9. 9.
    Brasnu E, Bourcier T, Dupas B et al (2007) In vivo confocal microscopy in fungal keratitis. Br J Ophthalmol 91(5):588–591CrossRefGoogle Scholar
  10. 10.
    Lee S, Yun NR, Kim KH et al (2010) Discrepancy between histology and culture in filamentous fungal infections. Med Mycol 48(6):886–888CrossRefGoogle Scholar
  11. 11.
    Schofield CM, Murray CK, Horvath EE et al (2007) Correlation of culture with histopathology in fungal burn wound colonization and infection. Burns 33(3):341–346CrossRefGoogle Scholar
  12. 12.
    Thomas PA (2003) Current perspectives on ophthalmic mycoses. Clin Microbiol Rev 16(4):730–797CrossRefGoogle Scholar
  13. 13.
    Zbiba W, Baba A, Bouayed E, Abdessalem N, Daldoul A (2016) A 5-year retrospective review of fungal keratitis in the region of Cap Bon. J Fr Ophtalmol 39(10):843–848CrossRefGoogle Scholar
  14. 14.
    Rautaraya B, Sharma S, Kar S, Das S, Sahu SK (2011) Diagnosis and treatment outcome of mycotic keratitis at a tertiary eye care center in eastern India. BMC Ophthalmol 11:39CrossRefGoogle Scholar
  15. 15.
    Punia RS, Kundu R, Chander J, Arya SK, Handa U, Mohan H (2014) Spectrum of fungal keratitis: clinicopathologic study of 44 cases. Int J Ophthalmol 7(1):114–117PubMedPubMedCentralGoogle Scholar
  16. 16.
    Prajna NV, Krishnan T, Mascarenhas J et al (2012) Predictors of outcome in fungal keratitis. Eye 26(9):1226–1231CrossRefGoogle Scholar
  17. 17.
    Ray KJ, Prajna NV, Lalitha P et al (2018) The significance of repeat cultures in the treatment of severe fungal keratitis. Am J Ophthalmol 189:41–46CrossRefGoogle Scholar

Copyright information

© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Eye Research Center, Farabi Eye HospitalTehran University of Medical SciencesTehranIran
  2. 2.Department of Medical Parasitology and Mycology, School of Public HealthTehran University of Medical SciencesTehranIran
  3. 3.Students’ Scientific Research CenterTehran University of Medical SciencesTehranIran

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