Severe Phenotype of Keratitis-Ichthyosis-Deafness Syndrome With Presumed Ocular Surface Squamous Neoplasia

Ocular phenotype and therapeutic interventions in keratitis-ichthyosis-deafness (KID) syndrome

BACKGROUND

To report ocular manifestations, clinical course, and therapeutic management of patients with molecular genetically confirmed keratitis-ichthyosis-deafness syndrome.

METHODS

Four patients, aged 19 to 46, with keratitis-ichthyosis-deafness syndrome from across the UK were recruited for a general and ocular examination and GJB2 (Cx26) mutational analysis. The ocular examination included best-corrected visual acuity, slit-lamp bio-microscopy, and ocular surface assessment. Mutational analysis of the coding region of GJB2 (Cx26) was performed by bidirectional Sanger sequencing.

RESULTS

All four individuals had the characteristic systemic features of keratitis-ichthyosis-deafness syndrome. Each patient was found to have a missense mutation, resulting in the substitution of aspartic acid with asparagine at codon 50 (p.D50N). Main ophthalmic features were vascularizing keratopathy, ocular surface disease, hyperkeratotic lid lesions, recurrent epithelial defects, and corneal stromal scarring. One patient had multiple surgical procedures, including superficial keratectomies and lamellar keratoplasty, which failed to prevent severe visual loss. In contrast, oral therapy with ketoconazole stabilized the corneal and skin disease in two other patients with keratitis-ichthyosis-deafness syndrome. The patient who underwent intracorneal bevacizumab injection showed a marked reduction in corneal vascularization following a single application.

CONCLUSIONS

Keratitis-ichthyosis-deafness syndrome is a rare ectodermal dysplasia caused by heterozygous mutations in GJB2 (Cx26) with a severe, progressive vascularizing keratopathy. Oral ketoconazole therapy may offer benefit in stabilizing the corneal and skin disease.

Advanced Anterior Eye Segment Imaging for Ichthyosis

The purpose of this study was to describe ocular surface and anterior eye segment findings in various types of ichthyoses.

METHODS

This was a single-center prospective observational study. The study group consisted of five patients (P1-P5) aged 13-66 years. Multimodal imaging was performed, including slit-lamp examinations, swept-source optical coherence tomography (SS-OCT), and in vivo confocal microscopy (IVCM).

RESULTS

All patients were diagnosed with moderate-to-severe dry eye disease (DED). The corneas showed a significant pattern of irregularity, with a significant difference between the corneal thickness at the apex (CAT) and the corneal thinnest thickness (CTT), exceeding 375 µm. Three patients were diagnosed with ectasia patterns based on SS-OCT. All patients showed abnormalities in at least one Fourier index parameter for at least one eye at 3 or 6 mm in the keratometric, anterior, or posterior analyses. IVCM examinations revealed changes in all corneal layers.

CONCLUSIONS

By combining the results of multimodal imaging, we were able to detect preclinical abnormalities, distinguish characteristic changes common to ichthyosis, and reveal the depth and characteristics of corneal abnormalities. Therefore, patients with ichthyosis should be examined for DED and ectatic disorders early in clinical practice.

Genetic predisposition to ocular surface disorders and opportunities for gene-based therapies

The ocular surface, comprised of the corneal and conjunctival epithelium, innervation system, immune components, and tear-film apparatus, plays a key role in ocular integrity as well as comfort and vision. Gene defects may result in congenital ocular or systemic disorders with prominent ocular surface involvement. Examples include epithelial corneal dystrophies, aniridia, ectrodactyly-ectodermal dysplasia-clefting (EEC) syndrome, xeroderma pigmentosum (XP), and hereditary sensory and autonomic neuropathy. In addition, genetic factors may interact with environmental risk factors in the development of several multifactorial ocular surface disorders (OSDs) such as autoimmune disorders, allergies, neoplasms, and dry eye disease. Advanced gene-based technologies have already been introduced in disease modelling and proof-of-concept gene therapies for monogenic OSDs. For instance, patient-derived induced pluripotent stem cells have been used for modelling aniridia-associated keratopathy (AAK), XP, and EEC syndrome. Moreover, CRISPR/Cas9 genome editing has been used for disease modelling and/or gene therapy for AAK and Meesmann's epithelial corneal dystrophy. A better understanding of the role of genetic factors in OSDs may be helpful in designing personalized disease models and treatment approaches. Gene-based approaches in monogenic OSDs and genetic predisposition to multifactorial OSDs such as immune-mediated disorders and neoplasms with known or possible genetic risk factors has been seldom reviewed. In this narrative review, we discuss the role of genetic factors in monogenic and multifactorial OSDs and potential opportunities for gene therapy.

Keratitis-ichthyosis-deafness syndrome: A comprehensive review of cutaneous and systemic manifestations

Keratitis-ichthyosis-deafness syndrome is a rare genetic disease presenting with cutaneous, ocular, and otic defects. This comprehensive review provides insight into the clinical presentations, highlighting the cutaneous manifestations including histopathology and treatment options.

The Clinical Manifestation of p.Asp50Asn Heterozygous Mutation of GJB2 Gene in 3 Members of a Family Is Similar to That of Clouston Syndrome

Keratitis-ichthyosis-deafness (KID) syndrome has genetic heterogeneity, and the clinical manifestations of some patients may overlap with Clouston syndrome. A 34-year-old female patient came to our department with a complain of “sparse hair, rough skin, photophobia and deafness for more than 30 years.” We found that the proband and two other family members (57-year-old mother and 4-year-old daughter) had similar clinical manifestations: systemic hair loss, generalized skin hyperkeratosis, especially in the metacarpophalangeal area. Subungual hyperkeratosis, finger/toenail dystrophy, as well as photophobia and epiphora. According to the investigation, one of the family members also had similar clinical manifestations (grandfather of the proband) and he’s died. The other three members of the family had no hearing impairment, and all patients had typical nail dystrophy, hair loss and palmoplantar hyperkeratosis, similar like as seen in Clouston syndrome, so we suspected to diagnose the case as Clouston syndrome. However, after genetic testing, it was found that the proband, his mother and daughter all had p.Asp50Asn heterozygous mutations in the GJB2 gene, and no mutation was detected in GJB6. The modified diagnosis was KID syndrome.

Ocular manifestations of skin diseases with pathological keratinization abnormalities

Keratinization means cytodifferentiation of keratinocytes turning into corneocytes in the stratum corneum. Disorders of keratinization (hyperkeratosis, parakeratosis and dyskeratosis) are causing many dermatological diseases, including various types of ichthyoses, pachyonychia congenita, pityriasis rubra pilaris, all subtypes of psoriasis, pityriasis lichenoides, dyskeratosis congenita, leukoplakia and keratosis follicularis, which apart from skin lesions may affect the eye’s adnexae causing ectropion, entropion, blepharitis, madarosis, and trichiasis, the ocular surface causing keratitis, conjunctivitis, corneal ulceration and episcleritis, which in turn cause uveitis and various fundoscopic changes (proliferative retinopathy, retinal vasculopathy, macular oedema and birdshot chorioretinopathy). Knowledge of ocular symtoms associated with pathological keratinization is crucial, preventing sight-threatening complications such as corneal perforation, lagophthalmus, phthisis bulbi, retinal neovascularization, retinal vasculopathy and optic nerve atrophy. This review encourages dermatologists to monitor patients for ocular symptoms and encourage ophthalmologists to monitor patients for dermatological symptoms.

Clinical, etiopathogenic, and therapeutic aspects of KID syndrome

Keratitis-ichthyosis-deafness (KID syndrome) is a syndromes ichthyoses that is clinically and genetically heterogeneous requiring early and long-term multidisciplinary monitoring of affected individuals. A review of the clinical, etiopathogenic and therapeutic aspects is presented of this rare congenital ectodermal disorder.