Inherited ichthyosis and fungal infection: an update on pathogenesis and treatment strategies.

Inherited ichthyoses are a group of genodermatoses classified as either nonsyndromic or syndromic. Nonsyndromic ichthyoses and keratitis, ichthyosis and deafness (KID) syndrome predispose to fungal infection. The diagnosis and treatment of fungal infections underlying ichthyoses are challenging. In this review, we summarize reported cases of ichthyosis with fungal infection over the past 50 years. Atypical manifestations such as alopecia, papules and brittle nails occurred in patients with ichthyosis combined with fungal infection. Various pathogenic mechanisms have been implicated, including mutations of ichthyosis-related genes leading to disruption of the skin barrier via multiple pathways. Host immune disorders, including atopy and abnormal innate immunity also contribute to susceptibility. Specific fungi may escape the immune response. Extensive and recurrent fungal infections are not uncommon in patients with ichthyosis, making a cure more difficult and increasing the need for systemic antifungal therapy. Traditional and new ichthyosis treatments aiming to improve skin barrier function could help prevent fungal infection. In conclusion, the close relationship between ichthyosis and fungal infection is of vital importance in clinical practice and requires more attention from physicians. More studies are required to investigate the mechanisms and explore useful treatment strategies.

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.

Verruciform xanthoma in recessive dystrophic epidermolysis bullosa and keratitis-ichthyosis-deafness syndrome: Report of two cases and a review of the literature.

Verruciform xanthoma is a benign, wart-like lesion that can clinically mimic squamous cell carcinoma. We describe two teenage patients with severe genodermatoses, recessive dystrophic epidermolysis bullosa (RDEB), and keratitis-ichthyosis-deafness (KID) syndrome, respectively, each found to have plaques suspicious for malignancy, later demonstrated on histopathologic examination to be verruciform xanthoma. We discuss the connection between these severe genodermatoses and the suspected pathophysiology of verruciform xanthoma. In addition, we highlight the importance of recognizing verruciform xanthoma as a clinical mimicker of squamous cell carcinoma, for which patients with RDEB and KID syndrome are at increased risk.

[Oral manifestations of KID syndrome: rare clinical case]. / Stomatologicheskie proiavleniia KID-sindroma: redkii klinicheskii sluchai.

The paper presents a rare clinical case of an infant with KID (Keratitis, Ichthyosis, Deafness) syndrome (about 100 patients reported so far) admitted for histological verification of oral mucosa lesions. Disease pathogenesis defines inadequate reparation and skin and mucosa innate immunity defect leading to higher incidence of bacterial and fungal infections, so the 4-years old girl received treatment for vegetating candidiasis of the oral mucosa for several weeks with no clinical improvement. Initial examination showed that the oral lesions resulted from sharp edges of severely affected carious teeth. Histological study of multifocal biopsy revealed pyogenic granulomas and no signs of SCC. Teeth extraction and symptomatic treatment leaded to significant clinical improvement and some remained mucosal changes may be attributed to syndrome manifestations.

Connexin 26 (GJB2) mutation in an Argentinean patient with keratitis-ichthyosis-deafness (KID) syndrome: a case report.

BACKGROUND: Keratitis-Ichthyosis-Deafness (KID) syndrome is a rare condition characterized by pre-lingual sensorineural deafness with skin hyperkeratinization. The primary cause of the disease is a loss-of-function mutation in the GJB2 gene. Mutations in Argentinean patients have not been described. CASE PRESENTATION: We studied a 2 year-old boy with bilateral congenital sensorineural deafness with dry skin over the entire body, hypotrichosis of the scalp, thin and light-blond hair. Analysis of the GJB2 gene nucleotide sequence revealed the substitution of guanine-148 by adenine predicted to result in an Asp50Asn amino acid substitution. CONCLUSION: This is the first KID report in a patient from Argentina. This de novo mutation proved to be the cause of keratitis-ichthyosis-deafness syndrome (KID-syndrome) in the patient, and has implications in medical genetic practice.

Connexin hemichannels influence genetically determined inflammatory and hyperproliferative skin diseases.

Connexin mutations underlie numerous human genetic diseases. Several connexin genes have been linked to skin diseases, and mechanistic studies have indicated that a gain of abnormal channel function may be responsible for pathology. The topical accessibility of the epidermal connexins, the existence of several mouse models of human skin disease, and the ongoing identification of pharmacological inhibitors targeting connexins provide an opportunity to test new therapeutic approaches.

Treatment of keratitis-ichthyosis- deafness (KID) syndrome in children: a case report and review of the literature.

Keratitis-ichthyosis-deafness (KID) syndrome is a rare hereditary cornification disorder resulting from mutations in connexin 26, a protein important for intercellular communication. In addition to the characteristic clinical triad of congenital bilateral sensorineural hearing loss, keratitis, and erythrokeratoderma, affected individuals also suffer from chronic bacterial and fungal infections and have an increased risk of benign and malignant cutaneous tumors. Treatments with antibiotics, antifungals, and systemic retinoids have been reported with variable response. Ocular and skeletal toxicity from prolonged exposure to systemic retinoids is a major concern especially in children. We report a case of a 7-year-old boy with KID syndrome complicated by frequent infections who responded well to acitretin 0.5-1.0 mg/kg/day. The patient had significant improvement of the hyperkeratosis on the scalp, trunk, and extremities within 4 weeks after initiating treatment. The patient has been on treatment for over a year without notable ocular, skeletal, or laboratory side effects. A review of the literature focusing on therapeutic options for KID syndrome and concerns about safety and tolerability is presented.

Otological problems in ichthyosis: A literature review.

BACKGROUND: Ichthyoses are a rare group of keratinization disorders characterized by scaling of the skin due to an impaired barrier function. Few studies have addressed ear involvement in patients with ichthyosis, although it is a probably underestimated aspect of the disease. OBJECTIVE: This study aims to provide an overview of the otological manifestations in ichthyosis and propose specific treatment options. METHODS: Articles were collected using PubMed, EMBASE, and Web of Science. A total of 53 articles were included in this literature review. RESULTS: The most common ear problem in patients with ichthyosis is scale accumulation in the ear canals, which can lead to conductive hearing loss and increases the risk of ear infections. Furthermore, some types of ichthyosis are associated with outer ear malformations. Lastly, sensorineural hearing loss is common in syndromic forms of ichthyosis. CONCLUSIONS: Otological problems are present in all types of ichthyoses and their treatment is challenging. The involvement of ear, nose, and throat specialists in the routine care of ichthyosis patients is essential for early identification and treatment of these manifestations. More research is needed to provide more insight into the otological problems in ichthyosis and to ameliorate treatment options.

Oral Nodular Chronic Hyperplastic Candidiasis of the Tongue: A Case Report.

Oral nodular chronic hyperplastic candidiasis (CHC) is a rare subset of oral CHC, a relatively uncommon condition associated with immunosuppression. We present a case of a 73-year-old female with nodular CHC of the tongue and a medical history noted for type 2 diabetes. Additionally, we discuss the diagnosis, management, and conditions potentially associated with oral nodular CHC.

Parental mosaic cutaneous-gonadal GJB2 mutation: From epidermal nevus to inherited ichthyosis-deafness syndrome.

Ichthyosis and deafness syndrome is a group of devastating genodermatoses caused by heterozygous mutations in GJB2, encoding the gap junction protein connexin 26. These syndromes are characterized by severe skin disease, hearing loss, recurrent infections, and cutaneous neoplasms. Cutaneous somatic mutations in the same gene are associated with porokeratotic eccrine ostial dermal duct nevus. Here we report a family in which a parent presented with localized epidermal nevus and his child suffered with hystrix-like ichthyosis with deafness. Histologic examination of the parent's cutaneous lesion revealed verrucous epidermal nevus without features of porokeratotic eccrine ostial dermal duct nevus. Genetic analysis identified the same pathogenic variant, GJB2 c.148G>A (p.D50N), in DNA extracted from the parent's cutaneous lesion and the child's leukocytes, but not in the parent's leukocytes. This study expands the phenotypic heterogeneity of GJB2 mosaic variants in addition to porokeratotic eccrine ostial dermal duct nevus, and emphasizes the importance of molecular diagnosis of mosaic skin diseases considering the risk of severe inherited diseases in the offspring.

Conformational changes and CO2-induced channel gating in connexin26.

Connexins form large-pore channels that function either as dodecameric gap junctions or hexameric hemichannels to allow the regulated movement of small molecules and ions across cell membranes. Opening or closing of the channels is controlled by a variety of stimuli, and dysregulation leads to multiple diseases. An increase in the partial pressure of carbon dioxide (PCO2) has been shown to cause connexin26 (Cx26) gap junctions to close. Here, we use cryoelectron microscopy (cryo-EM) to determine the structure of human Cx26 gap junctions under increasing levels of PCO2. We show a correlation between the level of PCO2 and the size of the aperture of the pore, governed by the N-terminal helices that line the pore. This indicates that CO2 alone is sufficient to cause conformational changes in the protein. Analysis of the conformational states shows that movements at the N terminus are linked to both subunit rotation and flexing of the transmembrane helices.

Keratitis-ichthyosis-deafness syndrome: first affected family reported in the Middle East.

INTRODUCTION: Keratitis-ichthyosis-deafness (KID) syndrome is a rare congenital multisystem disorder affecting certain tissues of ectodermal origin such as epidermis, cochlea, and cornea, leading mainly to palmoplantar hyperkeratosis, ichthyosiform scaling, deafness, and blindness. The author reports for the first time in the Middle East three family members suffering from KID syndrome in the southwestern part of Saudi Arabia. CASE PRESENTATION: Three patients from one family (ages 26, 16, and 14 years) of apparently normal parents, with the two eldest being females and the youngest being male. All three patients were referred from a peripheral hospital to our dermatology clinic due to recurrent cutaneous fungal infections on their trunk, forearms, legs, and nails. On full assessment, they also found to have nearly similar cutaneous problems manifested by palmoplantar hyperkeratosis, generalized ichthyosiform scaling, subungual hyperkeratosis, and nail dystrophies. All patients suffered from total hearing loss in both ears since childhood as confirmed by pure tune audiometry. However, there was no blindness in any case; blepharitis with marked photophobia was the only ocular complaint. All these features are classically suggestive of KID syndrome.

Nevo poroqueratósico del ostium y el ducto dérmico ecrinos: reporte de caso / Porokeratotic eccrine ostial and dermal duct nevus: case report

El Nevo Poroqueratósico del Ostium y el Ducto Dérmico Ecrinos (NPODDE), es un raro hamartoma benigno de los conductos de las glándulas sudoríparas ecrinas, puede presentarse desde el nacimiento o también en edades posteriores. Su etiología plantea una alteración en la queratinización debido a una mutación somática en el gen GJB2 que codifica para una proteína de unión gap. Esta mutación también está relacionada con el síndrome KID por lo cual la asesoría genética es crucial en estos pacientes. Clínicamente puede presentarse como hoyuelos hiperqueratósicos en palmas y plantas que normalmente son asintomáticos. El diagnostico se confirma con la histopato-logía que muestra una laminilla cornoide sobre el conducto ecrino subyacente. La entidad es benigna y de difícil tratamiento siendo refractaria a varias modalidades terapéuticas. Se presenta un caso de un paciente adulto masculino con lesiones típicas en palmas y plantas, a quien con la biopsia de piel se le confirmó el diagnóstico de NPODDE. Dado la baja frecuencia de esta condición el objetivo de este artículo radica en actualizar los aspectos más relevantes de esta entidad.

Porokeratotic Eccrine Ostial and Dermal Duct Nevus (PEODDN) is a rare benign hamartoma of eccrine sweat gland ducts, it can present from birth or also at later ages. Its etiology implies an alteration in keratinization due to a somatic mutation in GJB2 gene, that codes for a gap junction protein. This mutation is also associated with KID syndrome so genetic counseling for parents is crucial. Clinically it can present as keratotic pits in palms and soles that are usually asymp-tomatic. The diagnosis is confirmed by histopathology that shows a cornoid lamellae on the underlying eccrine duct. The entity is benign and the treatment is difficult, being refractory to seve-ral therapeutic modalities. We present a case of a male adult patient with typical lesions on palms and soles, who was diagnosed with PEODDN by skin biopsy. Given the low frequency of this con-dition, the objective of this article is to update the most relevant aspects of this entity.

Imaging Keratitis-Icthyosis-Deafness (KID) syndrome with FDG-PET (F18-fluorodeoxiglucose-Positron Emission Tomography).

Keratitis-Icthyosis-Deafness (KID) syndrome is a rare dysplasia characterized by vascularizing keratitis, congenital sensorineural hearing-loss, and progressive erythrokeratoderma. To our knowledge, this is the first KID syndrome imaged with FDG-PET in the literature. This paper is intended to help familiarize with the FDG abnormalities related to this rare entity.

Multiple Scalp Lesions in a Patient with Keratitis, Ichthyosis and Deafness Syndrome Mimicking Metastatic Squamous Cell Carcinoma on 18F-FDG PET/CT.

We report the case of a 17-year-old girl with keratitis, ichthyosis, and deafness (KID) syndrome. As a complication of her KID syndrome she developed squamous cell carcinoma at the left index finger. Additional clinical features were multiple soft tissue lesions over the scalp mimicking metastatic disease on 18F-FDG PET/CT. To our knowledge, this is the first case report about the uptake pattern of KID syndrome associated skin lesions on whole body PET/CT with 18F-FDG.