Drug-induced lipidoses of the cornea and conjunctiva

Drug-induced corneal deposits: an up-to-date review

This review assesses different clinical aspects of the various known drug-induced corneal deposits, based on the corneal layer involved (epithelium, stroma and/or endothelium), and based on the drug class. The most well-known condition caused by drug deposits is vortex keratopathy, or corneal verticillata, which is a whorl-like opacity in the corneal epithelium. Vortex keratopathy is commonly caused by certain cationic amphiphilic drugs such as amiodarone, antimalarials, suramin, tamoxifen, chlorpromazine and non-steroidal anti-inflammatory drugs. These deposits usually occur once a certain dose of the drug is reached. Most cases present with mild to moderate symptoms with minimal visual impairment. Most of these deposits resolve automatically, after months to years of drug cessation. Notably, other drug classes can cause deposits in all three layers of the cornea. Chlorpromazine, gold, rifabutin, indomethacin and tyrosine kinase inhibitors can cause stromal deposits, with reduced visual acuity when the anterior stroma is involved. Chlorpromazine and rifabutin can also cause deposits in the endothelial layer of the cornea. Regardless of the type of corneal deposit, local therapies such as topical lubricants or corticosteroids may help improve symptoms. Drug cessation or modification can also be helpful but should be weighed against the systemic risks of the underlying disease.

Short-term, high-dose hydroxychloroquine corneal toxicity

Purpose

To describe the corneal findings and management of a 61-year-old female with vortex keratopathy following short term, high dose hydroxychloroquine used in the setting of a clinical trial for recurrent breast cancer.

Observations

The patient was found to have significant corneal vortex keratopathy without retinal pathology within 3 months of 1200 mg daily hydroxychloroquine treatment as an adjuvant medication for cancer therapy. Cessation of the medication led to the resolution of the corneal verticillata within 1 month yet the vision did not return to baseline. Ultimately, remaining irregular astigmatism and ocular surface disease required a scleral contact lens to achieve a BSCVA of 20/25 OU.

Conclusions and Importance

Hydroxychloroquine-induced vortex keratopathy is largely considered dose and duration dependent and is uncommon with most standard treatment algorithms. However, with increasing use of high-dose hydroxychloroquine in adjunct cancer therapy, corneal findings are likely to become more frequent. Persistent visual impairment may occur, thus increased understanding of this pathology can aid in counseling patients and guiding treatment recommendations.

Markedly increased ocular side effect causing severe vision deterioration after chemotherapy using new or investigational epidermal or fibroblast growth factor receptor inhibitors

Background

We sought to describe corneal epithelial changes after using epidermal (EGFR) or fibroblast growth factor receptor (FGFR) inhibitors as chemotherapy and to clarify incidence and prognosis.

Materials

Retrospective chart review.

Results

Among 6871 patients and 17 EGFR or FGFR inhibitors, 1161 patients (16.9%) referred for ophthalmologic examination. In total, 1145 patients had disease-related or unrelated ocular complications. Among 16 patients with treatment-related ocular complications, three patients had treatment-related radiation retinopathy and one patient showed treatment-related corneal ulcer. Finally the authors identified that, in 12 patients, three EGFR inhibitors and two FGFR inhibitors caused corneal epithelial lesions. Vandetanib, Osimertinib, and ABT-414 caused vortex keratopathy in nine patients, while ASP-5878 and FPA-144 caused epithelial changes resembling corneal dysmaturation in three patients. The mean interval until symptoms appeared was 246 days with vandetanib, 196 days with osimertinib, 30 days with ABT-414, 55 days with ASP-5878, and 70 days with FPA-144. The mean of the lowest logarithm of minimal angle of resolution visual acuity results of the right and left eyes after chemotherapy were 0.338 and 0.413. The incidence rates of epithelial changes were 15.79% with vandetanib, 0.5% with osimertinib, 100% with ABT-414, 50.0% with ASP-5878, and 18.2% with FPA-144. After excluding deceased patients and those who were lost to follow-up or still undergoing treatment, we confirmed the reversibility of corneal lesions after the discontinuation of each agent. Seven patients showed full recovery of their vision and corneal epithelium, while three achieved a partial level of recovery. Although patients diagnosed with glioblastoma used prophylactic topical steroids before and during ABT-414 therapy, all developed vortex keratopathy.

Conclusions

EGFR and FGFR inhibitors are chemotherapy agents that could make corneal epithelial changes. Contrary to the low probability of ocular complication with old EGFR drugs, recently introduced EGFR and FGFR agents showed a high incidence of ocular complication with severe vision distortion. Doctors should forewarn patients planning chemotherapy with these agents that decreased visual acuity could develop due to corneal epithelial changes and also reassure them that the condition could be improved after the end of treatment without the use of steroid eye drops.

Trial registration

This study was approved by the institutional review board (IRB) of Samsung Medical Center (IRB no. 2019–04-027) and was conducted according to the principles expressed in the Declaration of Helsinki.

Vortex Pattern of Corneal Deposits in Granular Corneal Dystrophy Associated With the p.(Arg555Trp) Mutation in TGFBI

PURPOSE

To describe 2 unrelated families with multiple members demonstrating a less commonly recognized vortex pattern of corneal deposits confirmed to be granular corneal dystrophy type 1 (GCD1) after identification of the p.(Arg555Trp) mutation in the transforming growth factor β-induced gene (TGFBI).

METHODS

A slit-lamp examination was performed on individuals from 2 families, one of Mexican descent and a second of Italian descent. After DNA extraction from affected individuals and their unaffected relatives, TGFBI screening was performed.

RESULTS

Eight of 20 individuals in the Mexican family and 20 of 55 in the Italian family demonstrated corneal stromal opacities. Seven of the 8 affected individuals in the Mexican family and 4 of the 20 affected individuals in the Italian family demonstrated a phenotype characterized by a "sea fan" or vortex pattern of superficial stromal corneal deposits originating from the inferior aspect of the cornea. Screening of TGFBI in both families revealed a heterozygous missense mutation [p.(Arg555Trp)] in exon 12, confirming the diagnosis of GCD1.

CONCLUSIONS

Our findings demonstrate that GCD1 may present with a vortex pattern of anterior stromal deposits. Although this pattern of dystrophic deposits is not recognized by clinicians as a typical phenotype of GCD1, it is consistent with the production of the majority of the TGFBI protein by the corneal epithelium.

Ocular toxicity from systemically administered xenobiotics

INTRODUCTION

The eye is considered as the most privileged organ because of the blood-ocular barrier that acts as a barrier to systemically administered xenobiotics. However, there has been a significant increase in the number of reports on systemic drug-induced ocular complications. If such complications are left untreated, then it may cause permanent damage to vision. Hence, knowledge of most recent updates on ever-increasing reports of such toxicities has become imperative to develop better therapy while minimizing toxicities.

AREAS COVERED

The article is mainly divided into anterior and posterior segment manifestations caused by systemically administered drugs. The anterior segment is further elaborated on corneal complications where as the posterior segment is focused on optic nerve, retinal and vitreous complications. Furthermore, this article includes recent updates on acute and chronic ocular predicaments, in addition to discussing various associated symptoms caused by drugs.

EXPERT OPINION

Direct correlation of ocular toxicities due to systemic drug therapy is evident from current literature. Therefore, it is necessary to have detailed documentation of these complications to improve understanding and predict toxicities. We made an attempt to ensure that the reader is aware of the characteristic ocular complications, the potential for irreversible drug toxicity and indications for cessation.

Vortex keratopathy in a patient receiving vandetanib for non-small cell lung cancer

We report a case of vortex keratopathy in a patient treated with vandetanib for non-small cell lung cancer (NSCLC). A 44-year-old female who underwent two cycles of chemotherapy for NSCLC complained of visual blurring in both eyes after the initiation of vandetanib, an anti-epidermal growth factor receptor (EGFR) and anti-vascular endothelial growth factor receptor 2 protein tyrosine kinase inhibitor. On ophthalmic examination, visual acuities were 20 / 20 OU and, with the exception of diffuse vortex keratopathy in both eyes, other findings were unremarkable. Vandetanib is believed to have caused vortex keratopathy in this patient. Anti-EGFR properties affecting normal corneal epithelial cell migration and wound healing or drug associated metabolite deposition, which is the case in numerous drug-associated vortex keratopathies, may be possible underlying mechanisms in the formation of this corneal complication.

Fabry disease

Fabry disease, an X-linked disorder of glycosphingolipids that is caused by the deficiency of alpha-galactosidase A, is associated with dysfunction of many cell types and includes a systemic vasculopathy. As a result, patients have a markedly increased risk of developing small-fiber peripheral neuropathy, stroke, myriad cardiac manifestations and chronic renal disease. Virtually all complications of Fabry disease are non-specific in nature and clinically indistinguishable from similar abnormalities that occur in the context of more common disorders in the general population. Although Fabry disease was originally thought to be very rare, recent studies have found a much higher incidence of mutations of the GLA gene, suggesting that this disorder is under-diagnosed. Although the etiology of Fabry disease has been known for many years, the mechanism by which the accumulating alpha-D-galactosyl moieties cause this multi-organ disorder has only recently been studied and is yet to be completely elucidated. Specific therapy for Fabry disease has been developed in the last few years but its role in the management of the disorder is still being investigated. Fortunately, standard 'non-specific' medical and surgical therapy is effective in slowing deterioration or compensating for organ failure in patients with Fabry disease. All these aspects are discussed in detail in the present review.

The microstructure of cornea verticillata in Fabry disease and amiodarone-induced keratopathy: a confocal laser-scanning microscopy study

PURPOSE

The purpose of this study is to describe cornea verticillata in Fabry disease and in amiodarone-induced keratopathy and to compare the corneal microstructure of both types.

PATIENTS AND METHODS

Ten eyes from ten normal subjects, 28 eyes from 22 patients with Fabry disease confirmed by molecular genetic studies, and 16 eyes from 11 patients receiving amiodarone were examined by slit-lamp microscopy and in-vivo confocal laser-scanning microscopy (CLSM) with following three-dimensional reconstruction of the individual corneal layers. Five patients with Fabry disease were monitored during the course of enzyme replacement therapy (ERT).

RESULTS

Evidence of cornea verticillata was found by slit-lamp microscopy both in patients with Fabry disease and in those with amiodarone-induced keratopathy; CLSM revealed the same pattern of hyper-reflective deposits in the basal cell layer of corneal epithelium in both sets of patients. Microdot changes in the anterior stroma were more prevalent in patients receiving amiodarone but do not presuppose the simultaneous presence of cornea verticillata. The bulbar conjunctiva was found to be normal in all patients. The tarsal conjunctival epithelium contained round hyper-reflective structures, which are also encountered physiologically, but these were more common in patients with Fabry disease. In one out of the five patients examined, monitoring of corneal changes over time during ERT disclosed a regressive tendency of the deposits in the epithelial basal cell layer documented by CLSM.

CONCLUSIONS

The microstructural corneal changes typically seen in cornea verticillata in both Fabry disease and in amiodarone-induced keratopathy can be successfully visualized by confocal in-vivo microscopy at the level of the basal cell layer. By analogy, with the grading system for cornea verticillata based on slit-lamp microscopy, staging of these deposits in the basal cell layer can also be performed following in-vivo CLSM. The microdots in the anterior stroma as well as the changes observed in the tarsal conjunctiva should be regarded as having less diagnostic value because such changes may also occur in normal subjects. The utility of CLSM as a tool for monitoring ERT in Fabry disease over time needs to be confirmed in studies with larger sample sizes conducted over a longer period.

Clinical and In Vivo Confocal Microscopy Findings in Patients Receiving Tamoxifen Citrate

PURPOSE

: To describe the deposition rate of tamoxifen in the cornea and observe its impact on the cornea with confocal microscopy.

METHODS

: Forty-four eyes of 22 women receiving tamoxifen at a dosage of 20 mg/day for at least 6 months for the adjuvant treatment of breast cancer and 30 eyes of 15 healthy age-matched women were examined for corneal drug deposition by slitlamp after pupil dilation. Ultrasound pachymetry, specular microscopy, in vivo confocal microscopy, and Schirmer tear test were also performed in all patients.

RESULTS

: The mean duration of tamoxifen intake was 21.6 +/- 7.9 months (range, 13-44 months), and the mean cumulative dose was 12.9 +/- 4.7 g (range, 7.8-26.4 g). Drug depositions in the inferior paracentral cornea were identified in 32 (72%) eyes at pupil-dilated slitlamp examination. There were no significant differences between eyes with keratopathy, those without keratopathy, and control eyes in regard to the mean Schirmer test scores, mean central corneal thickness, mean endothelial cell count, mean basal epithelium cell density, mean anterior and posterior stromal keratocyte density, and mean endothelial cell density (P > 0.05). No pathologic alteration of structure was observed with in vivo confocal microscopy at any corneal level in patients receiving tamoxifen.

CONCLUSIONS

: Low-dose tamoxifen use was associated with corneal depositions in 72% of patients. Slitlamp examination performed with pupil dilation was helpful in detection of subtle tamoxifen-related deposits. Amelioration of in vivo confocal microscopy systems may be helpful in accurate imaging of the paracentral and peripheral cornea.

Drug-induced corneal complications

PURPOSE OF REVIEW

To review the common corneal manifestations of systemic medications in order to describe the characteristic clinical features associated with particular systemic drugs, the indications for drug cessation, and the risks for irreversible ocular toxicity.

RECENT FINDINGS

Systemic medications may reach the cornea via the tear film, aqueous humor, and limbal vasculature. The corneal changes are often the result of the underlying chemical properties of medications. Amphiphilic medications (amiodarone, chloroquine, suramin, clofazimine, etc.) may produce a drug-induced lipidosis and development of a vortex keratopathy. Antimetabolites (cytarabine) may lead to a degeneration of basal epithelial cells with formation of epithelial microcysts. Additionally, systemically administered medications and drug metabolites may lead to a stromal or endothelial deposition. Corneal changes may result in reduced visual acuity, photophobia, and ocular irritation, though these symptoms typically resolve following drug cessation. Corneal manifestations of systemic medications are often dose related, and may reflect the potential risk for lenticular or retinal changes.

SUMMARY

Corneal changes secondary to systemic medications may affect all layers of the cornea. While corneal deposition is typically not an indication for drug cessation, patients receiving particular medications should be monitored for symptoms related to corneal deposition as well as for signs of irreversible ocular toxicity.

Band-shaped and whorled microcystic dystrophy of the corneal epithelium

OBJECTIVE

To report the clinical, histopathologic, and electron microscopic features of band-shaped and whorled microcystic corneal epithelial dystrophy.

DESIGN

Two interventional case reports.

PARTICIPANTS

Two patients, two eyes.

INTERVENTION

The involved area of corneal epithelium was scraped from each cornea.

RESULTS

Histopathologic examination showed microscopic vacuoles in the epithelial cytoplasm in both cases. Electron microscopic examination revealed mainly empty cytoplasmic vacuoles with scant nonspecific osmophilic material. The process recurred clinically in one patient. Changes in corneal topography are documented in one patient.

CONCLUSION

Clinical findings and pathologic studies seem nearly identical to those in the original report. No pattern of systemic disorder or medication use was found. The cause of this condition remains unknown.

Vortex keratopathy associated with atovaquone

PURPOSE

We studied a case of vortex keratopathy that was associated with the use of atovaquone.

METHOD

A patient with acquired immunodeficiency syndrome (AIDS) with pulmonary Pneumocystis carinii was treated with 750 mg of atovaquone three times a day.

RESULTS

Similar to previous findings of drug-induced vortex keratopathy, atovaquone vortex keratopathy is presumably caused by its lipophilic properties. This property is similar to that of other lipophilic agents such as amiodarone, chloroquine, chlorpromazine, quinacrine, and suramin.

CONCLUSION

Atovaquone should be added to the list of agents causing vortex keratopathy involving the corneal epithelium.

Corneal lipidosis in patients with the acquired immunodeficiency syndrome

PURPOSE

Certain drugs bind to anionic phospholipids of lysosomal membranes and produce progressive intracellular accumulation of lamellar inclusions. We studied two patients treated for opportunistic infections associated with the acquired immunodeficiency syndrome (AIDS), who developed bilateral ocular surface changes suggestive of drug-induced corneal lipidosis.

METHODS

Two patients with AIDS had translucent vacuoles within the corneal epithelium and mild conjunctival hyperemia. Because the differential diagnosis included microsporidial keratoconjunctivitis, biopsies of the ocular surface were performed for histopathologic analysis.

RESULTS

Transmission electron microscopy of corneal epithelial debridement and conjunctival biopsy specimens showed intracellular, electron-dense lipoidal bodies and multilaminated lysosomal inclusions suggestive of a drug-induced lipidosis. Both patients also had tubuloreticular inclusions in conjunctival capillary endothelial cells. The ocular surface changes resolved within one to three months after dosage reduction or discontinuation of systemic ganciclovir and acyclovir.

CONCLUSIONS

Drug-induced phospholipidosis is a cause of punctate corneal epitheliopathy during AIDS, but the responsible agent remains to be identified.

Development of atypical amiodarone keratopathy in a corneal graft

The presence of fine epithelial deposits in a whorled pattern (cornea verticillata) as a consequence of treatment with amiodarone is well documented. We present a case of amiodarone keratopathy in a grafted cornea which is atypical in that the orientation of the pattern is rotated through nearly 90 degrees to that normally observed. This observation runs counter to the hypothesis that cornea verticillata is a manifestation of the line of lid closure. We speculate on the mechanism directing the migrational pathways of epithelial cells.

Comparative toxicity of intravitreal aminoglycoside antibiotics

We compared the toxicity of the aminoglycoside antibiotics (tobramycin, amikacin, netilmicin, and kanamycin) by ophthalmoscopy, light and electron microscopy, and electro-retinography after intravitreal injection in rabbits in doses ranging from 100 to 3,000 micrograms. The earliest manifestations of toxicity were confined to the outer retina with each drug, with lamellar lysosomal inclusions in the retinal pigment epithelium as the earliest finding. However, the aminoglycosides displayed marked differences in the threshold dose required to produce toxic reactions, permitting the following ordering of toxicity: (most toxic) gentamicin greater than netilmicin = tobramycin greater than amikacin = kanamycin (least toxic).

Severe ocular side effects of perhexilene maleate: case report

We report a case of perhexilene maleate (PEXID) toxicity in which the presenting feature was loss of vision secondary to chronic papilloedema. Vortex keratopathy similar to that seen in amiodarone keratopathy was present, and corneal and conjunctival biopsy findings are presented. To our knowledge this is the first case report of a keratopathy occurring in perhexilene toxicity. After withdrawal of the drug the papilloedema and keratopathy subsided, but some visual deficit remains. The properties of perhexilene maleate and other amphiphilic drugs are described, and the possible aetiology of vortex keratopathy is discussed.

Chloroquine-induced inhibition of rat serum muramidase activity in vivo in relation to tissue changes

Chloroquine was tested for its inhibitory effect in vivo on the activities of rat serum and tissue muramidase. Daily administration of this anti-malarial drug to rats resulted in an appreciable reduction of kidney and liver enzyme activities 1 day after the first dose. No corresponding increases in enzyme activity were detected in the serum of treated animals up to day 9 when muramidase activity was then significantly reduced. Activity observed in the heart tissue was not affected until day 12, when the level was significantly reduced. These results suggest that chronic chloroquine administration to rats may result in an extensive inhibition of muramidase activity probably at the cellular/molecular level.