An unusual case of herpes simplex keratitis presenting as persistent epithelial defect after pterygium surgery

Gaurav Mahajan; Pawan Prasher

doi:10.4103/IJO.IJO_3133_22

Users Online: 43

CASE REPORT

Year : 2023 | Volume : 3 | Issue : 2 | Page : 281-282

An unusual case of herpes simplex keratitis presenting as persistent epithelial defect after pterygium surgery

Gaurav Mahajan, Pawan Prasher
Department of Ophthalmology, Sri Guru Ram Das Institute of Medical Sciences and Research, Amritsar, Punjab, India

Date of Submission	29-Nov-2022
Date of Acceptance	09-Feb-2023
Date of Web Publication	28-Apr-2023

Correspondence Address:
Pawan Prasher
Department of Ophthalmology, Sri Guru Ram Das Institute of Medical Sciences and Research, Vallah, Amritsar, Punjab
India

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/IJO.IJO_3133_22

Abstract

Pterygium is a common conjunctival degeneration and surgical excision is the mainstay of treatment. HSV keratitis after ocular surgery has been attributed to various factors including reactivation of latent infection secondary to surgical trauma to the corneal subepithelial nerve plexus and the modulation of the ocular immune response in the postoperative period caused by steroids. In the current case, the patient had persistent epithelial defect which was non responsive to routine topical lubricant therapy and showed a classical dendritic ulcer pattern upon staining with fluorescein dye. Upon initiation of conventional anti-viral therapy, the patient improved and the epithelial defect was gradually healed. HSV keratitis can rarely present as a non-healing epithelial defect after pterygium surgery and a close follow-up in the post-operative period, timely diagnosis and prompt antiviral therapy plays an important role in achieving a favourable clinical outcome in such cases.

Keywords: Epithelial defect, Herpes simplex virus, pterygium

How to cite this article:
Mahajan G, Prasher P. An unusual case of herpes simplex keratitis presenting as persistent epithelial defect after pterygium surgery. Indian J Ophthalmol Case Rep 2023;3:281-2

How to cite this URL:
Mahajan G, Prasher P. An unusual case of herpes simplex keratitis presenting as persistent epithelial defect after pterygium surgery. Indian J Ophthalmol Case Rep [serial online] 2023 [cited 2023 Jun 2];3:281-2. Available from: https://www.ijoreports.in/text.asp?2023/3/2/281/375024

Pterygium is a common degeneration of the conjunctiva and surgical excision is the mainstay of treatment. Pterygium surgery can be associated with various complications including scleral ulceration, necrotizing scleritis, perforation, iridocyclitis, cataract formation, glaucoma, scleral calcification,^[1] and visually devastating microbial keratitis. Various types of postoperative microbial keratitis that have been reported include marginal keratitis caused by Staphylococcus, mitomycin-C-associated scleral melt and secondary infection, peripheral ulcerative keratitis, and Fusarium-associated keratitis.^{[1],[2],[3],[4]} However, to the best of our knowledge herpes simplex virus (HSV) keratitis following pterygium excision surgery has not been previously reported in literature. Herein, we present a unique case of persistent epithelial defect after pterygium surgery that was diagnosed as HSV epithelial keratitis. The case is particularly noteworthy, given that the patient was otherwise healthy and had no obvious risk factors for ocular HSV.

Case Report

A 69-year-old woman was referred to the cornea clinic for the management of a persistent epithelial defect in her left eye. She had undergone uneventful pterygium excision using bare sclera technique without mitomycin C in that eye three weeks ago in a camp setting. Postoperatively, she had been prescribed moxifloxacin 0.5% and carboxy methyl cellulose 0.5% eye drops; however, she developed a persistent epithelial defect for which she was referred for cornea consultation. She had undergone cataract surgery in her right eye 1.5 years ago but did not have good visual outcome. The systemic history and examination were unremarkable. On presentation, she complained of persistent watering, redness, and irritation in the left eye since the time of surgery. The best-corrected visual acuity was hand movements in both eyes. On slit-lamp examination, the left eye showed superficial vascularization with underlying stromal haze from 7 o'clock to 10 o'clock positions in the nasal half of the left cornea [Figure 1]a. On staining with 2% fluorescein, two epithelial defects measuring 6 × 4 mm and 4 × 3 mm and exhibiting a characteristic dendritic pattern with terminal bulbs and involving the nasal half of the cornea and nasal limbal area were noted [Figure 1]b. Corneal sensations were found to be diminished and the lens showed cataractous changes. Examination of the right eye revealed localized edema that seemed to be more due to surgery rather than endothelial decompensation. A clinical diagnosis of HSV epithelial keratitis in the left eye was made and the patient was started on tablet acyclovir 400 mg five times daily, acyclovir (5%) eye ointment five times daily, carboxymethyl cellulose (0.5%) eye drops four times daily, and homatropine (2%) eye drops three times daily. The patient responded well to the treatment, and there was gradual resolution of symptoms. On day 3 of follow-up, the epithelial defect had reduced in size [Figure 1]c and on day 7 of therapy, the epithelial defect had completely healed [Figure 1]d. At two weeks of follow up, the patient was completely asymptomatic, and at that time topical antiviral therapy was discontinued and oral acyclovir was tapered to 400 mg twice maintenance dose. There was no recurrence over the period of the next six months.

Figure 1: Slit-lamp evaluation showing superficial vascularization with underlying stromal haze (a). Fluorescein staining shows characteristic dendritic pattern with terminal bulbs involving the nasal half of the cornea and nasal limbal area (b). Decrease in epithelial defect on day 3 (c). Completely healed epithelial defect on day 7 (d)

Click here to view

Discussion

HSV keratitis after ocular surgery has been well documented in the literature^[5],[6],[7] and has been attributed to various factors including reactivation of latent infection secondary to surgical trauma to the corneal subepithelial nerve plexus and the modulation of the ocular immune response in the postoperative period caused by steroids.^[5],[6] Previous studies have reported the presence of HSV antigens in conjunctival specimens and have suggested its role in the pathogenesis of pterygium formation. It is likely that some of these patients harbour HSV in latent form in their conjunctiva which can potentially be activated in the presence of a skin-trigger type mechanism.^[8],[9] Although the current patient was not using any systemic or topical steroids and did not have any other systemic disease-causing immunosuppression, we speculate it to be as a result of activation of a latent HSV infection due to surgical trauma.

Infective keratitis after pterygium surgery have been rare and can present as a corneal infiltrate, abscess, corneal or scleral thinning, and perforation. Various microorganisms previously reported postoperatively after pterygium surgery include Staphylococcus, Pseudomonas aeruginosa, Aspergillus, Mycobacterium fortuitum, and Fusarium species.^[2],[4],[10] Our patient presented with classical manifestations of dendritic ulcer consistent with HSV epithelial keratitis, which had earlier been misinterpreted by the referring surgeon as persistent epithelial defect. The diagnosis in the current case was clinical, and virology laboratory investigation was not available due to logistical reasons; the investigation would otherwise have helped in confirming the presence of HSV. The patient responded well to conventional antiviral therapy with resolution of symptoms and healing of epithelial defect; this supports the diagnosis of HSV keratitis in the current case.

Conclusion

In conclusion, HSV keratitis can rarely present as a non-healing epithelial defect after pterygium surgery, and ophthalmologists need to be aware of this possibility. Although the operating surgeon had correctly labelled it as an epithelial defect, fluorescein staining in this case showed terminal bulbs which are characteristic of HSV epithelial keratitis. Therefore, the importance of fluorescein staining in a patient with non-healing epithelial defect postoperatively after pterygium surgery should not be overlooked and staining should be preferably done in every case. Timely diagnosis and prompt antiviral therapy play an important role in achieving a favorable clinical outcome in such cases.

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

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1.	Soleimani M, Tabatabaei SA, Mehrpour M, Salabati M, Mahmoudzadeh R. Infectious keratitis after pterygium surgery. Eye (Lond) 2020;34:986-8.
2.	Liu X, Ye X, Bi Y. Staphylococcus-associated marginal keratitis secondary to pterygium surgery: A case report. BMC Ophthalmol 2021;21:157.
3.	Gokhale NS. Peripheral ulcerative keratitis after pterygium surgery. Indian J Ophthalmol 2003;51:105-6. [PUBMED] [Full text]
4.	Merle H, Guyomarch J, Joyaux JC, Dueymes M, Donnio A, Desbois N. Keratomycosis complicating pterygium excision. Clin Ophthalmol 2011;5:1435-7.
5.	Gessa-Sorroche M, Kanclerz P, Alio J. Evidence in the prevention of the recurrence of herpes simplex and herpes zoster keratitis after eye surgery. Arch Soc Esp Oftalmol (Engl Ed) 2022;97:149-60.
6.	Patel NN, Teng CC, Sperber LT, Dodick JM. New-onset herpes simplex virus keratitis after cataract surgery. Cornea 2009;28:108-10.
7.	Prasher P, Muftuoglu O. Herpetic keratitis after descemet stripping automated endothelial keratoplasty for failed graft. Eye Contact Lens 2009;35:41-2.
8.	Spandidos D, Xinarianos G, Ergazaki M, Giannoudis A, Tsamparlakis J. The presence of herpesviruses in pterygium. Int J Oncol 1994;5:749-52.
9.	Detorakis ET, Sourvinos G, Spandidos DA. Detection of herpes simplex virus and human papilloma virus in ophthalmic pterygium. Cornea 2001;20:164-7.
10.	Hsiao CH, Chen JJ, Huang SC, Ma HK, Chen PY, Tsai RJ. Intrascleral dissemination of infectious scleritis following pterygium excision. Br J Ophthalmol 1998;82:29-34.