Histological Effects of Intravitreal Injection of Antifungal Agents in New Zealand White Rabbits: An Electron
Sofia Karachrysafi1, Antonia Sioga1, Anastasia Komnenou2
1Laboratory of Histology-Embryology, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece.
Abstract:
Fungal endophthalmitis is a serious and vision-threatening infection which requires an immediate and effective treatment approach. Our research aims to elucidate the histological effects of the intravitreal injection of the maximum safe dosage of voriconazole and micafungin on retina. Six albino New Zealand White Rabbits were used. In experimental animals, a solution of voriconazole (Group V) or micafungin (Group M) was intravitreally injected in the right eye, while in control animals, balanced salt solution was intravitreally injected in the left eye (Group C). Euthanasia was performed ten days post injection and the retina was removed and prepared for histological examination with a light and electron microscope. Eosin-hematoxylin staining did not reveal any pathological changes in any of the samples examined. The immunohistochemical staining for Tumor Necrosis Factor alpha (TNF-a) marker was detected as negative in all samples, while Interleukin 6 (IL-6) marker was detected as mild only in the group injected with voriconazole. Electron microscopy revealed several ultrastructural alterations in retinal layers in both groups of experimental animals. Histological retinal lesions, revealed with electron microscopy in the present investigation, raises the question of the safe usage of these antifungal agents in the treatment of fungal intraocular infections in the future.
Insights
Intravitreal voriconazole and micafungin showed minimal inflammatory markers but caused retinal ultrastructural changes in rabbits. Further research is needed to confirm the safety of these antifungals for treating fungal endophthalmitis.
Area of Science:
- Ophthalmology
- Mycology
- Histopathology
Background:
- Fungal endophthalmitis is a severe ocular infection demanding prompt treatment.
- Antifungal agents are crucial for managing these infections.
- Understanding the retinal impact of intravitreal antifungals is vital for patient safety.
Purpose of the Study:
- To investigate the histological effects of intravitreal voriconazole and micafungin on rabbit retinas.
- To assess the safety profile of maximum safe dosages of these antifungal agents.
- To evaluate potential retinal damage from these treatments.
Main Methods:
- Albino New Zealand White Rabbits were used, with intravitreal injections of voriconazole, micafungin, or balanced salt solution.
- Retinal tissues were examined using light microscopy (H&E staining) and electron microscopy.
- Immunohistochemistry was performed for Tumor Necrosis Factor alpha (TNF-a) and Interleukin 6 (IL-6).
Main Results:
- Routine histology and TNF-a staining showed no significant pathological changes.
- Mild IL-6 expression was observed in the voriconazole group.
- Electron microscopy revealed ultrastructural alterations in retinal layers in both antifungal-treated groups.
Conclusions:
- While voriconazole and micafungin demonstrated minimal inflammatory response via standard markers, ultrastructural retinal changes were observed.
- These findings raise concerns about the long-term safety and usage of these antifungals in treating fungal endophthalmitis.
- Further investigation is warranted to fully understand the implications for clinical application.
