|Year : 2021 | Volume
| Issue : 2 | Page : 246-248
Infectious crystalline keratopathy caused by Candida parapsilosis in a turgid host cornea
Alok Sati, Lavan Singh, Sanjay Kumar Mishra, Sonali V Kumar, Sanjay Kumar Dhar
Army Hospital (Research and Referral), Delhi Cantt, Delhi, India
|Date of Submission||22-Aug-2020|
|Date of Acceptance||30-Oct-2020|
|Date of Web Publication||01-Apr-2021|
Prof. Alok Sati
Army Hospital (Research and Referral), Delhi Cantt, Delhi - 110 010
Source of Support: None, Conflict of Interest: None
A 62 yearold male had a primary failed descemet stripping automated endothelial keratoplasty (DSAEK) following an eventful DSAEK surgery and was kept on long-term topical steroid in a tapering dosage. 5 months later, the turgid host cornea developed a pearly white crystalline anterior stromal infiltrate suggestive of infectious crystalline keratopathy (ICK). Gram stain smear revealed gram-positive, round to oval, large, budding cells which exhibit blue-white florescence with calcofluor white stain. Species level identification as Candida parapsilosis, in addition to the antifungal sensitivity, was aided by a yeast reagent card on VITEK 2 compact automated microbiology system. Based of antifungal sensitivity report, the patient was treated with both oral fluconazole and topical antifungals and responded to the management. Clinical diagnosis of ICK with a mandatory microbiological workup is prudent for a successful outcome.
Keywords: ICK, Candida parapsilosis, DSAEK
|How to cite this article:|
Sati A, Singh L, Mishra SK, Kumar SV, Dhar SK. Infectious crystalline keratopathy caused by Candida parapsilosis in a turgid host cornea. Indian J Ophthalmol Case Rep 2021;1:246-8
|How to cite this URL:|
Sati A, Singh L, Mishra SK, Kumar SV, Dhar SK. Infectious crystalline keratopathy caused by Candida parapsilosis in a turgid host cornea. Indian J Ophthalmol Case Rep [serial online] 2021 [cited 2021 Apr 14];1:246-8. Available from: https://www.ijoreports.in/text.asp?2021/1/2/246/312394
Originally reported by Gorovoy in 1983, infectious crystalline keratopathy (ICK), a rare disorder, is characterized by an arborized needle-like intrastromal opacities with a limited inflammation. Candida parapsilosis (C. parapsilosis), a rarest ocular pathogen of ICK, has so far been reported only twice following varied surgical settings i.e., penetrating keratoplasty and phacoemulsification., Herein, we report, for the first time, C. parapsilosis caused ICK, in a turgid host cornea following failed descemet stripping automated endothelial keratoplasty (DSAEK), which was successfully managed with the medical treatment.
| Case Report|| |
A 62-year-old male, a known case of pseudophakic bullous keratopathy (PBK), underwent an eventful DSAEK in the left eye (LE). As a result, primary DESK failure was noted. However, topical steroid (eyedrop prednisolone acetate 1%), in tapering dosage, was continued on the follow-up visits. Patient was offered for re-DSAEK, though, denied for the same.
Five months post DSAEK, patient presented with pain, redness and watering in the LE. CDVA was hand movement close to face. Lids were swollen, circumcorneal congestion present, host cornea showed a 3 × 3 mm central epithelial defect overlying a pearly white crystalline anterior stromal infiltrate with multiple needles like projections [Figure 1], in addition to the surrounding hypertrophied epithelium, multiple bullae and diffuse stromal edema suggestive of failed DSEK. Rest details were hazily seen with absence of echogenicity on USG B-scan.
|Figure 1: Slit-amp photograph at an initial visit shows features suggestive of crystalline keratopathy|
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Corneal scrapings of the lesion were obtained and subjected to both the smear preparation and culture. Smears were prepared for KOH mount and Grams stain. Culture was performed on media including sheep blood agar, 5.0% chocolate agar and Sabouraud dextrose agar. All media were incubated aerobically at 37°C except Sabouraud dextrose agar which was incubated at 25°C for 2 weeks. Gram stain smear at × 100 magnification shows multiple, gram-positive, round to oval, large, budding cells which exhibit blue-white florescence with calcofluor white stain [Figure 2]a and [Figure 2]b. Culture on chocolate agar exhibits confluent white colonies with discrete margins, 24 hours after incubation at 37°C [Figure 3].
|Figure 2: Gram stain photograph showing multiple gram-positive budding yeast cells (a). Confirmation of fungus as yeast cells on calcofluor white stain (b)|
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|Figure 3: Creamy white colonies on chocolate agar suggestive of candida spp|
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Genus level identification was achieved by the above-mentioned techniques whereas the species level identification as C. parapsilosis, in addition to the antifungal sensitivity, was aided by a yeast reagent card on VITEK 2 compact automated microbiology system (bioMerieiux, France) with 99% probability. The organism was sensitive to fluconazole (MIC: ≤0.5), voriconazole (MIC: ≤0.2), capsofungin (MIC: 1.0), micafungin (MIC: 2.0), amphotericin B (MIC: 0.5) and flucytosine (MIC: ≤0.1).
Based of antifungal sensitivity report, the patient was treated with oral fluconazole (150 mg, twice daily), topical voriconazole (1%, 1 hourly) and cycloplegic. One week later, topical voriconazole was tapered to 2 hourly along with oral fluconazole and cycloplegic. Six weeks later, the infected area turned into the scar in the turgid cornea and the antifungals continued for four more weeks to ensure the complete eradication of candida spp. [Figure 4].
| Discussion|| |
Candida parapsilosis, though discovered by Ashford in 1928, has emerged a major human pathogen over past 2 decades. Being a normal human commensal, acquires pathogenicity in an immunocompromised state through hydrolytic enzymes, adherence to biotic/abiotic surface and the formation of biofilm. Its pathogenic role in ICK is well documented in the compact corneal tissues, though not reported in a relatively turgid tissue, where an amorphic bacterial colonies are being expected.
Herein, we report an ICK in a relatively turgid host cornea following a primary failure of DSAEK graft. For C. parapsilosis, to develop an ICK, an epithelial defect and a localized immunosuppression, are mandatorily required. The former developed in our case secondary to ruptured bullae and the latter is facilitated by the long-term administration of topical steroid.
Due to localized immunosuppression, the seeded C. parapsilosis became the sessile pathogen, surrounded by the biofilm, allowing its gradual spread across lamellae with limited surrounding inflammation, resulting in a discrete keratitis with a crystalline pattern.
Though Streptococcus viridans, S. epidermidis, S. pneumonia, Haemophilus spp., and enterococci are mainly implicated in ICK; however, Candida spp. and mycobacteria must be kept in mind, especially in patients on long term topical steroid. Hence, it is prudent to have a meticulous microbiological evaluation for an accurate identification of organism and the sensitivity pattern. [Table 1] depicts the antifungal sensitivity pattern at our center to common antifungals in systemic candidiasis against the Candida spp. including C. parapsilosis. In addition, the sensitive drug needs to be administered in a higher concentration to have an effect on an organism inside the biofilm. Based on the above facts, we administered fortified voriconazole on an hour basis initially and two hourlies subsequently to have an adequate therapeutic concentration inside the biofilm.
|Table 1: Pattern of Anti-fungal drug sensitivity of various common candida spp|
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| Conclusion|| |
To conclude, ICK in a turgid cornea is an unusual presentation and can easily be avoided by a definitive treatment of a failed DSEK graft and a timely reduction of localized immunosuppression. Since a plethora of organisms attribute to ICK and the characterization of crystalline pattern does not correlate with a specific organism, it is prudent to have a definitive diagnosis and sensitivity pattern for a successful management.
Declaration of patient consent
The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Figure 1], [Figure 2], [Figure 3], [Figure 4]