Archipelago Keratitis

Herpes simplex virus, varicella-zoster virus and cytomegalovirus keratitis: Facts for the clinician

Keratitis due to Herpes simplex virus (HSK), Varicella-Zoster virus (VZK) and Cytomegalovirus remains a frequent source of concern for many ophthalmologists. They are a frequent cause of emergency consultations at eye care centers and carry the risk of permanent loss of visual acuity or visual quality and/or chronic neurotrophic keratitis, resulting in a significant decrease in the quality of life. HSK and VZK can affect the corneal epithelium, stroma, or endothelium or a combination of layers. In contrast, most cases of CMV keratitis present as isolated endothelitis (CMVE), a clinical entity that has been described within the last 2 decades. These three types of viral keratitis are characterized by a high frequency of recurrences and each new episode increases the risk of sequelae. Hence, ophthalmologists must adapt the treatment to the clinical presentation of each recurrent episode in order to mitigate the immediate consequences of viral replication and the immune response on corneal transparency. In patients with frequent recurrences, preventive long-term antiviral treatment is strongly recommended. However, in some rare cases, continuous exposure to antivirals may promote the emergence of resistant viral strains, which can be difficult to manage. In the future, the introduction of new antiviral drugs, with differing modes of action compared to current medical therapy, could be an alternative until a truly effective preventive solution, such as a vaccine, is available.

Clinical course and treatment of archipelago keratitis: a Herpesviridae keratitis subtype

PURPOSE

Archipelago keratitis (ApK) is a subtype of Herpesviridae stromal keratitis that consists of subepithelial nummular inflammatory infiltrates arranged in a radial centripetal pattern. This rare and poorly described form is not often recognised early. We report the first large series of ApK, with an analysis of clinical settings at presentation, evolution of the disease with time and a description of factors associated with recurrence.

METHODS

The clinical records of 82 patients (83 eyes) with a diagnosis of ApK between 2011 and 2021 in two centres were reviewed.

RESULTS

The median age of the 82 patients at referral was 37±28 years. ApK was unilateral in all but one case. A total of 76% of patients had at least one second diagnostic criteria suggesting a herpetic aetiology. Overall, 44 (53%) eyes exhibited least one recurrence after a median of 12 months. Recurrence was frequently associated with neovascularisation (HR 2.1, 95% CI 1.1 to 3.9; p=0.02) and tapering corticosteroids (HR 3.5, 95% CI 1.8 to 7.1; p<0.01) or valaciclovir use (HR=2.3, 95% CI 1.2 to 4.6; p=0.01). Antiviral treatment was used in all patients, whereas local anti-inflammatory drugs such as corticosteroids and/or ciclosporin were used in 73 (88%) cases.

CONCLUSION

ApK is a Herpesviridae stromal keratitis that is typically unilateral in presentation and features a high risk of recurrence. Combined treatment with antiviral and anti-inflammatory drugs are usually required over the long term. Topical ciclosporin can be useful as a corticosteroid-sparing treatment.

Multifocal Vortex Keratopathy

PURPOSE

To report the clinical features, laboratory investigation, and histological findings of an individual with a 14-year history of an idiopathic multifocal vortex epithelial keratopathy.

METHODS

We describe the clinical appearance, the clinical course, and the response to treatment. We report the results of corneal epithelial culture, laboratory investigation for potential pathogens, and histopathology.

RESULTS

The signs were consistent with focal areas of corneal inflammation that produced abnormal epithelial cells that were carried in vortex patterns by the direction of epithelial flow. In vivo confocal microscopy demonstrated hyperreflective structures within the epithelial cell layer, but with only minor signs of stromal disease, similar to Thygeson superficial punctate keratitis. Culture, polymerase chain reaction, and serology did not support an infectious etiology, and histopathology showed nonspecific inflammation of the epithelial layer. Symptoms of photophobia and blur, with multiple exacerbations, required the almost continuous use of topical corticosteroid or ciclosporin over 14 years.

CONCLUSIONS

The clinical course, as well as the response to topical corticosteroid and ciclosporin, suggests that this is distinct from Thygeson superficial punctate keratitis. The etiology is unknown.

20 years since the Herpetic Eye Disease Study: Lessons, developments and applications to clinical practice

Herpes Simplex Virus (HSV) is the most common virus that causes eye disease. Although around 60% of the world's population are seropositive for HSV antigens, fortunately, it is estimated that only 1% of seropositive individuals develop eye disease. The most common ocular manifestation of HSV is keratitis, while uveitis and retinal necrosis occur in a small number of cases. HSV keratitis is a debilitating disease, for several reasons: pain , photophobia, and vision loss in acute disease, latency of the virus which leads to infection reactivation from various triggers, scarring, and neovascularisation, leading to permanent vision loss with poor visual rehabilitation prospects. The Herpetic Eye Disease Study (HEDS) was a landmark series of randomised controlled trials in the 1990s that set the benchmark for evidence-based treatment guidelines for anterior eye herpetic disease. Since this time, there has been a change in the distribution of seroprevalence of herpes in the community, a simplified diagnostic classification, advances in treatment options, an emergence of new and a better understanding of risk factors, and discoveries in science that show promise for vaccine and novel future treatments. However, many of the principles of the HEDS study remain rightly entrenched in clinical practice. In this article, the HEDS study is revisited 20 years on through the lens of published literature, to determine current best practise and look towards the future.

In Vivo confocal microscopic changes of the corneal epithelium and stroma in patients with herpes zoster ophthalmicus

PURPOSE

To analyze the density and morphology of corneal epithelial cells and keratocytes by in vivo confocal microscopy (IVCM) in patients with herpes zoster ophthalmicus (HZO) as associated with corneal innervation.

DESIGN

Prospective, controlled and masked cross-sectional study.

METHODS

setting: Single-center study.

PATIENTS

Thirty eyes with the diagnosis HZO and their contralateral clinically unaffected eyes, 15 eyes of 15 normal controls. intervention procedures: In vivo confocal microscopy and corneal esthesiometry of the central cornea.

MAIN OUTCOME MEASURES

Changes in morphology and density of the superficial and basal epithelial cells and stromal keratocytes, and correlation with corneal sensation.

RESULTS

The density of superficial epithelial cells in HZO eyes with severe sensation loss (766.5 ± 25.2 cells/mm(2)) was significantly lower than both healthy control eyes (1450.23 ± 150.83 cells/mm(2)) and contralateral unaffected eyes (1974.13 ± 298.24 cells/mm(2)) (P = .003). Superficial epithelial cell size (1162.5 μm(2)) was significantly larger in HZO eyes with severe loss of sensation, as compared to contralateral (441.46 ± 298.14) or healthy eyes (407.4 ± 47.2μm(2); all P < .05). The density of basal epithelial cells, anterior keratocytes, and posterior keratocytes did not show statistical significance between patients, controls, and contralateral unaffected eyes. Changes in superficial epithelial cell density and morphology correlated strongly with corneal sensation.

CONCLUSIONS

In vivo confocal microscopy reveals profound HZO-induced changes in the superficial epithelium, as demonstrated by increase in cell size, decrease in cell density, and squamous metaplasia. We demonstrate that these changes strongly correlate with changes in corneal innervation in eyes affected by HZO.

Staphylococcus aureus Blepharitis Associated with Multiple Corneal Stromal Microabscess, Stromal Edema, and Uveitis

We report a case of an immunocompetent woman with atypical marginal keratitis. She presented with recurrent episodes of multiples microabscess distributed in a triangular pattern associated with stromal oedema and anterior chamber uveitis, affecting both eyes, but not simultaneously. The episodes responded to steroid drops, corneal inflammation was coincidental with a worsening of her blepharitis in the affected eye and S. aureus was isolated from the lids.

Corneal densitometry evaluation in archipelago keratitis

To report a case of archipelago keratitis and its improvement as evaluated by corneal densitometry. A review of the patient's record and relevant literature. A 57-year-old man presented with blurred vision associated with photophobia and halos around lights. Slit-lamp examination revealed multiple confluent, nummular subepithelial infiltrates. The infiltrates were unresponsive to topical nonsteroidal anti-inflammatory drops. The treatment was changed to topical steroids and oral acyclovir and a diagnosis of archipelago keratitis was made. The patient showed quick response to the treatment and the infiltrates disappeared within 5 weeks. However, no clear changes were observed initially by slit-lamp but corneal densitometry allowed us to evaluate improvement as the density value decreased from 96.5 to 38.6. After 10 days of treatment all the symptoms were resolved. Archipelago keratitis responded well to topical steroids and oral acyclovir. We describe the use of corneal densitometry complementary to slit-lamp examination in the clinical observation of archipelago keratitis.

Cellular changes of the corneal epithelium and stroma in herpes simplex keratitis: an in vivo confocal microscopy study

PURPOSE

To analyze the morphologic features of corneal epithelial cells and keratocytes by in vivo confocal microscopy in patients with herpes simplex keratitis (HSK) as associated with corneal innervation.

DESIGN

Prospective, cross-sectional, controlled, single-center study.

PARTICIPANTS

Thirty-one eyes with the diagnosis HSK and their contralateral clinically unaffected eyes were studied and compared with normal controls (n = 15).

METHODS

In vivo confocal microscopy (Confoscan 4; Nidek Technologies, Gamagori, Japan) and corneal esthesiometry (Cochet-Bonnet; Luneau Ophthalmologie, Chartres, France) of the central cornea were performed bilaterally in all patients and controls. Patients were grouped into normal (>5.5 cm), mild (>2.5-5.5 cm), and severe (<2.5 cm) loss of sensation.

MAIN OUTCOME MEASURES

Changes in morphologic features and density of the superficial and basal epithelial cells, as well as stromal keratocytes, were assessed by 2 masked observers. Changes were correlated to corneal sensation, number of nerves, and total length of nerves.

RESULTS

There was a significant and gradual decrease in the density of superficial epithelial cells in HSK eyes, with 852.50 ± 24.4 cells/mm(2) in eyes with severe sensation loss and 2435.23 ± 224.3 cells/mm(2) in control eyes (P = 0.008). Superficial epithelial cell size was 2.5-fold larger in HSK eyes (835.3 μm(2)) compared with contralateral or normal eyes (407.4 μm(2); P = 0.003). A significant number of hyperreflective desquamating superficial epithelial cells were present in HSK eyes with normal (6.4%), mild (29.1%), and severe (52.2%) loss of sensation, but were absent in controls. The density of basal epithelial cells, anterior keratocytes, and posterior keratocytes did not show statistical significance between patients and controls. Changes in superficial epithelial cell density and morphologic features correlated strongly with total nerve length, number, and corneal sensation. Scans of contralateral eyes did not show any significant epithelial or stromal changes compared with controls.

CONCLUSIONS

In vivo confocal microscopy reveals profound HSK-induced changes in the superficial epithelium, as demonstrated by increase in cell size, decrease in cell density, and squamous metaplasia. This study demonstrated that these changes correlate strongly with changes in corneal innervation.

In vivo laser confocal microscopy findings of Thygeson superficial punctate keratitis

PURPOSE

We looked for microstructural corneal characteristics of Thygeson superficial punctate keratitis (TSPK) in an in vivo investigation using laser scanning confocal microscopy.

METHODS

Five patients (3 men and 2 women; mean age, 51.8 years) with clinically diagnosed TSPK were enrolled in this study. All patients were examined by slit-lamp biomicroscopy and in vivo laser confocal microscopy. Deposits in selected confocal images of all corneal layers were evaluated qualitatively for shape and degree of light reflection.

RESULTS

The most characteristic finding was aggregates of highly reflective deposits with a starburst-like appearance that corresponded with epithelial punctate lesions identified by slit-lamp biomicroscopy; the aggregates were sporadically observed in all cases at the superficial and basal epithelial cell layers. Subepithelial haze was observed in all cases. Langerhans cells were also sporadically observed in all cases at the basal epithelial layer. Bowman layer abnormalities were observed in 3 of 5 cases; all these patients had a long history of TSPK (eg, more than 1 year). In addition, the 3 patients had highly reflective, tiny, needle-shaped materials in the corneal stroma.

CONCLUSIONS

In vivo laser confocal microscopy is capable of identifying characteristic corneal microstructural changes related to TSPK with a higher resolution than is available with slit-lamp biomicroscopy. It may also be a valuable tool for further research to elucidate both pathogenesis and the natural course of TSPK.