Recent advances in understanding ichthyosis pathogenesis

Exploring Digital Dermatology: An Analysis of Ichthyosis Content on TikTok

Background TikTok is among the most popular social media sites, and its utilization for health information is growing each day. The present study assesses the popularity and quality of the top 100 most-liked videos on TikTok tagged with "#ichthyosis." This study aims to do so by assessing contributions from physician, and nonphysician sources (such as from patients) to guide healthcare professionals interested in leveraging this platform for public health.  Methodology A cross-sectional analysis of the top 100 most-liked videos tagged with "#ichythosis" on TikTok as of January 3, 2024, was conducted. The parameters assessed for this study include observable characteristics, content type, and whether the creator was a physician or nonphysician. The quality of the content was measured using the DISCERN scale.  Results Based on these results, 14 of the top 100 videos were posted by physicians with 1,912,975 as the mean number of views. There were 86 videos posted by nonphysician creators averaging 2,675,341 views. Videos posted by nonphysician creators had a higher average number of views, number of likes, and number of comments but less average saves. Videos made by physicians and educational content had the highest average DISCERN scores, whereas nonphysician, awareness, and personal experience content had the lowest average DISCERN scores.  Conclusions Physicians are deemed trustworthy, reliable sources of healthcare-related information on TikTok. This study emphasizes the importance of physicians continuing to provide reliable, evidence-based health information on social media platforms such as TikTok.

Mitigating Infection Risk in Upper Airway Stimulation

OBJECTIVE

This study aims to define the incidence of infection with upper airway stimulation (UAS) devices requiring explantation in a single academic center and identify factors that may influence the risk of infection.

METHODS

A database of patients who underwent UAS at a single tertiary referral academic center from 2017 to 2021 was retrospectively reviewed to identify patients who developed surgical site infections, with and without subsequent explantation. Additional data for cases complicated by infection was extracted from the electronic medical record (EMR) and included: demographic information, medical history, complications and management, and overall outcomes. In March 2021, 2 modifications to infection control protocols were implemented: double skin preparation with Betadine and chlorhexidine, and MRSA decolonization. Statistical analysis was performed to compare infectious risk before and after these protocol changes.

RESULTS

In the study period, 215 patients underwent UAS in the specified time period and 3 cases (1.4%) of postoperative infections were identified, all of which required explantation. The infection rate did not significantly change after modifications to the surgical prep protocol (P = .52).

CONCLUSIONS

While no significant difference in infection risk was noted after modifying infection control protocols, additional longer-term study is warranted to elucidate effective infection reduction strategies.

Ichthyosis Skin Changes in a Patient With Hereditary Hemochromatosis

Hereditary hemochromatosis (HH) is characterized by elevated iron absorption in the body, leading to iron accumulation with subsequent dysfunction and end-organ damage. While the progression of the disease can result in arthralgias, hepatomegaly, cardiomyopathies, and diabetes, over a third of HH patients present with cutaneous manifestations. We present the case of a 56-year-old male with HH who presented to dermatology with a rash and diffuse scaling. The patient exhibited brown plate-like scales clinically consistent with diffuse ichthyosis vulgaris. While ichthyosis has been seen in patients with idiopathic hemochromatosis, its association with HH is not well reported. Due to the high prevalence of cutaneous involvement in hereditary hemochromatosis, physicians should familiarize themselves with ichthyosis and the other dermatologic manifestations of this disease.

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.

Congenital ichthyosis: a multidisciplinary approach in a neonatal care unit

Congenital ichthyoses are a rare group of genetic disorders caused by defects in the two outermost skin layers, resulting in an abnormal barrier function. We report the case of a male preterm neonate presenting at delivery with thickened and scaling skin, ectropium and eclabium. Supportive care aiming at improving skin condition and handling possible complications was provided. Following gradual clinical improvement, he was discharged after 27 days. Molecular testing identified mutations in a gene encoding lipoxygenase (ALOX12B), associated with autosomal recessive congenital ichthyosis. This case highlights an uncommon disease that can determine significant morbidity and mortality in the first few weeks of life. Management of this complex disease benefits from a multidisciplinary approach. Molecular studies allow a more accurate diagnosis and enable genetic counselling.

Psychosocial implications of rare genetic skin diseases affecting appearance on daily life experiences, emotional state, self-perception and quality of life in adults: a systematic review

BACKGROUND

Since the beginning of human genetic research, there are very few publications sharing insights of the negative impact of rare genetic skin diseases (RGSD) on patients' experiences. This systematic review assessed the psychosocial implications of these conditions in terms of daily life experiences, emotional state, self-perception, and Quality of Life (QoL).

METHODOLOGY

A systematic review was carried out on albinism, neurofibromatosis type 1 (NF1), birthmarks and inherited ichthyosis. The PubMed, Scopus, PsycArticle, PsychInfo, Psychology and Behavioral Sciences Collection, and SOCindex databases were queried. Inclusion criteria were adult patients with one of these RGSDs. Simple descriptive statistics and qualitative content analysis were conducted to summarize the main results reported by the authors.

RESULTS

Of the 9987 articles retrieved, 48 articles were included: albinism (16), NF1 (16), inherited ichthyosis (10), birthmarks (6). The majority of the studies on albinism were conducted in Africa. Twenty-seven studies quantitatively assessed diverse psychological parameters: 13 showed a significant impact of the disease on QoL, five on emotional state, two on self-representation and two others on psychiatric comorbidities. Disease severity and visibility were good predictors of QoL (except for albinism). Body image and appearance concerns were also associated with QoL and emotional state. The 19 qualitative studies highlighted recurring themes across each of these diseases: discrimination and stigma during childhood and adolescence, discomfort in social interactions, guilt of transmission, the importance of social support from family and friends, altered daily life functioning, altered romantic and sex life, limited academic and professional aspirations, lack of interest and support from the medical field, and the unpredictability of the evolution of the disease. The only two mixed-method studies in this review were unable to contribute to any inferential analyses but could corroborate some of the qualitative findings.

CONCLUSION

These results showed that RGSDs have a significant impact on different aspects of patients' lives. This review has demonstrated that there is a real need for support systems for patients with these diseases. Such systems should be developed to provide them with necessary information and to guide them through an appropriate care pathway.

Transcriptomic Analysis of the Major Orphan Ichthyosis Subtypes Reveals Shared Immune and Barrier Signatures

Preliminary work suggested upregulation of inflammatory pathways in patients with common forms of ichthyosis. However, a comprehensive characterization of skin from various ichthyosis subtypes is unavailable, precluding the development of targeted treatments. Thus, we sought to characterize the immune and barrier profiles of common and subtype-specific skin transcriptomes in a large group of patients with ichthyosis. We performed a global RNA-sequencing analysis in 54 patients with ichthyosis (7 with Netherton syndrome, 13 with epidermolytic ichthyosis, 16 with lamellar ichthyosis, and 18 with congenital ichthyosiform erythroderma) and 40 healthy controls. Differentially expressed genes were defined on the basis of fold changes > 2 and false discovery rate < 0.05 criteria. We found robust and significant T helper (Th) 22/Th17 skewing in all subtypes (e.g., IL-17A/C/F, S100A7/8/9/12; P < 0.001) with modest changes in Th2 pathway, primarily in Netherton syndrome, and Th1 skewing in congenital ichthyosiform erythroderma. Across all subtypes (less evident in epidermolytic ichthyosis), lipid metabolism and barrier junction markers were downregulated (e.g., FA2H, CDH10/11/12/2; P < 0.05), whereas epidermal cornification and proliferation measures were upregulated (e.g., SPRR1A/1B/2C/2G, EREG; P < 0.05). Our findings suggest that the common ichthyosis variants share aberrations in Th17/Th22 and barrier function, with minimal Th2 modulation. This may help to elucidate the pathogeneses of these subtypes and inform the development of subtype-specific treatments.

Scaling skin and failing heart: the cardio-cutaneous connection

Ichthyosis refers to a comparatively rare group of skin disorders which may present with associated cardiomyopathy. We report a case of an 11-year-old female child who presented with ichthyosis and associated dilated cardiomyopathy. Genetic testing revealed mutation in the RBCK1 gene. She was successfully managed with heart transplantation. The purpose of the case report is to embark on the association between the skin and heart, the role of desmosomes, and the cutaneous manifestations of life-threatening cardiac disease. Cutaneous manifestations should not be escaped, as some of which could be a marker for sudden cardiac death and appropriate corrective actions can potentially save life.

Analysis of the structure and function of the epidermal barrier in patients with ichthyoses - clinical and electron microscopical investigations

BACKGROUND

Ichthyoses are pathogenetically characterised by a pronounced disorder of the epidermal barrier. Clinically, hyperkeratosis, severe scaling and erythroderma are present on the entire integument. The time-consuming therapy includes daily baths and the application of skin care products to restore the epidermal barrier.

OBJECTIVES AND METHODS

To enhance the knowledge about the structure and function of the epidermal barrier in ichthyoses, we conducted clinical, biophysical and electron microscopical measurements on 46 patients with ichthyoses, including autosomal recessive ichthyoses, keratinopathic ichthyoses, X-chromosomal recessive ichthyosis and Netherton syndrome.

RESULTS

The patients displayed a significantly decreased skin hydration along with unexpectedly low transepidermal waterloss values. Electron microscopical examinations demonstrated a severe occlusion of the epidermis by lipid remnants of skin care products in the stratum corneum. We found decreased intercellular lipid lamellae and an increased undulation of the corneocyte membrane of all ichthyoses, mostly pronounced in Netherton syndrome. The lipid profiles of ichthyoses showed decreased esterified Ω-hydroxy-sphingosine (EOS) ceramide levels.

CONCLUSIONS

The results demonstrate the extent of the epidermal barrier disruption in ichthyoses. In combination with the knowledge about pathogenetic causes, individually improved therapeutic options can be derived from our results. In the future, the analyses of the organisation of intercellular lipid lamellae and corneocyte membrane undulation will enable improved investigations of the epidermal barrier in ichthyoses and may be used to study and evaluate possible effects of topical skin preparations.

DSP missense variant in a Scottish Highland calf with congenital ichthyosis, alopecia, acantholysis of the tongue and corneal defects

BACKGROUND

Ichthyosis describes a localized or generalized hereditary cornification disorder caused by an impaired terminal keratinocyte differentiation resulting in excessive stratum corneum with the formation of more or less adherent scales. Ichthyosis affects humans and animals. Two rare bovine forms are reported, the severe harlequin ichthyosis and the less severe congenital ichthyosis, both characterized by a severe orthokeratotic lamellar hyperkeratosis.

RESULTS

A 2-weeks-old purebred Scottish Highland calf was referred because of a syndrome resembling congenital ichthyosis. The clinical phenotype included diffuse alopecia and a markedly lichenified skin covered with large and excessive scales. Additionally, conjunctivitis and ulceration of the cornea were noted. Post-mortem examination revealed deep fissures in the diffusely thickened tongue and histopathological findings in the skin confirmed the clinical diagnosis. Whole-genome sequencing of the affected calf and comparison of the data with control genomes was performed. A search for private variants in known candidate genes for skin phenotypes including genes related with erosive and hyperkeratotic lesions revealed a single homozygous protein-changing variant, DSP: c.6893 C>A, or p.Ala2298Asp. The variant is predicted to change a highly conserved residue in the C-terminal plakin domain of the desmoplakin protein, which represents a main intracellular component of desmosomes, important intercellular adhesion molecules in various tissues including epidermis. Sanger sequencing confirmed the variant was homozygous in the affected calf and heterozygous in both parents. Further genotyping of 257 Scottish Highland animals from Switzerland revealed an estimated allele frequency of 1.2%. The mutant allele was absent in more than 4800 controls from various other cattle breeds.

CONCLUSIONS

This study represents the first report of combined lesions compatible with congenital ichthyosis, alopecia, acantholysis of the tongue and corneal defects associated with a DSP missense variant as the most likely underlying cause. To the best of our knowledge, this study is also the first report of a DSP-related syndromic form of congenital ichthyosis in domestic animals. The results of our study enable genetic testing to avoid the unintentional occurrence of further affected cattle. The findings were added to the Online Mendelian Inheritance in Animals (OMIA) database (OMIA 002243-9913).

Percutaneous metals absorption following exposure to road dust powder

The skin constitutes a protective barrier to external physical and chemical aggressions. Although it is constantly exposed to various xenobiotics, it is generally considered poorly permeable to them, as for example metal ions, becoming unfortunately an entry route of such substances. Metals may penetrate inside the skin inducing more or less local effects such as skin sensitization and potential metals diffusion into the bloodstream. The objective of the study was to investigate the percutaneous penetration of metals in vitro - ex vivo in Franz cell with intact as well damaged skin applying a road dust powder. Moreover, porcine and human skins were compared. This study demonstrated that, after the application of a road dust powder on the skin, metals can penetrate and permeate this cutaneous membrane. From this experimental analysis, in intact skin lead (Pb) achieved the highest skin absorption in both human and porcine skin, while skin absorption profile of cobalt (Co) was the lowest in human skin than the one in porcine model. The concentrations of Ni present in receiving solution were higher compared to other metals in all experiments performed. The present work, definitely shows that metals permeation through damaged skin is accelerated than intact skin, as a result of the weaker cutaneous barrier function. According to published data, pig skin appeared as a suitable model for human skin. Our results confirmed that skin absorption of metals can be relevant in environmental exposures.

A frameshift insertion in FA2H causes a recessively inherited form of ichthyosis congenita in Chianina cattle

The aim of this study was to characterize the phenotype and to identify the genetic etiology of a syndromic form of ichthyosis congenita (IC) observed in Italian Chianina cattle and to estimate the prevalence of the deleterious allele in the population. Sporadic occurrence of different forms of ichthyosis including IC have been previously reported in cattle. However, so far, no causative genetic variant has been found for bovine IC. Nine affected cattle presenting congenital xerosis, hyperkeratosis and scaling of the skin as well as urolithiasis and cystitis associated with retarded growth were examined. Skin histopathology revealed a severe, diffuse orthokeratotic hyperkeratosis with mild to moderate epidermal hyperplasia. The pedigree records indicated a monogenic recessive trait. Homozygosity mapping and whole-genome sequencing allowed the identification of a homozygous frameshift 1 bp insertion in the FA2H gene (c.9dupC; p.Ala4ArgfsTer142) located in a 1.92 Mb shared identical-by-descent region on chromosome 18 present in all cases, while the parents were heterozygous as expected for obligate carriers. These findings enable the selection against this sub-lethal allele showing an estimated frequency of ~ 7.5% in Chianina top sires. A sporadic incidence of mild clinical signs in the skin of heterozygous carriers was observed. So far, pathogenic variants affecting the encoded fatty acid 2-hydroxylase catalyzing the synthesis of 2-hydroxysphingolipids have been associated with myelin disorders. In conclusion, this study represents the first report of an FA2H-related autosomal recessive inherited skin disorder in a mammalian species and adds FA2H to the list of candidate genes for ichthyosis in humans and animals. Furthermore, this study provides a DNA-based diagnostic test that enables selection against the identified pathogenic variant in the Chianina cattle population. However, functional studies are needed to better understand the expression of FA2H in IC-affected Chianina cattle.

Ichthyosis (concept, pathohistology, clinical picture, treatment)

Ichthyosis is a skin disease that is hereditary, has pronounced symptoms in the form of a violation of the skin, and the presence of formations resembling fish scales. It is possible to distinguish different approaches to the definition of ichthyosis, based on the modern study of this issue. Ichthyosis is classified by type: congenital and acquired. Congenital ichthyosis has its own classification depending on the manifestation of changes in the skin, the course of the disease, concomitant pathologies. Congenital ichthyosis is divided into ordinary (vulgar autosomal dominant, simple) ichthyosis, lamellar ichthyosis (dry ichthyosiform erythroderma, "collodion child", lamellar ichthyosis), X-linked ichthyosis (ichthyosis associated with the X chromosome, blackening ichthyosis), congenital bullous ichthyosiform erythroderma (erythroderma Broca's disease, ichthyosiform epidermolytic hyperkeratosis), fetal ichthyosis (intrauterine ichthyosis, universal hyperkeratosis, "Harlequin fetus", congenital keratosis), other congenital ichthyosis. Ichthyosiform conditions (the so-called acquired ichthyosis) are divided into symptomatic, age-related (senile), discoid ichthyosis. The causes of acquired ichthyosis can be various diseases, taking medications, improper skin care, unbalanced nutrition. Each form of ichthyosis differs by the type of inheritance, prevalence in the population, clinical picture, verified by histological examination of skin biopsies and electron microscopic examination of the skin. It may be accompanied by seasonality of exacerbation of the clinical picture, association with other diseases (allergic, diseases of the gastrointestinal tract, congenital malformations). There is no specific treatment for ichthyosis. In systemic therapy, derivatives of vitamin A are used, keratolytics, as well as moisturizing and emollient agents are used for external treatment. The use of therapeutic baths, general ultraviolet irradiation is effective.

A review of quality of life of patients suffering from ichthyosis

Introduction

Ichthyoses include a heterogeneous group of skin diseases often characterized by persistent scaling and hyperkeratosis with variable erythema, pruritus, and sweating impairment. The aim of our review was to assess the quality of life in patients with ichthyosis.

Methods

In July 2018 we performed a systematic search in the electronic database PubMed (MEDLINE). The MESH term “quality of life” was combined, through the Boolean operator AND with the key word “ichthyosis”. We considered eligible for the systematic review studies written in English.

Results

The literature search yielded 63 publications, but 7 studies were included in the review. Studies were published in 2003-2014 and involved a minimum of 10 and a maximum of 235 patients. Authors used 5 types of tools: Dermatology Life Quality Index (DLQI), Dermatitis Family Impact Questionnaire (DFI), Nottingham Health Profile (NHP) questionnaire, Short Form Questionnaire 36 and 12 (SF-36, SF-12). Many patients reported worse scores than general population. Patients referred physical problems related to pain (which negatively influenced the mobility).

Conclusions

Ichthyosis considerably impaired the QoL, especially for paediatric patients. Further studies and efforts should be done to manage and treat the pain.

Subtle and unexpected role of PEG in tuning the penetration mechanisms of PLA-based nano-formulations into intact and impaired skin

We present a systematic study of the role of poly(ethylene glycol) (PEG) content in NPs on drug skin absorption. Cholecalciferol-loaded NPs of 100 nm of diameter were prepared by flash nanoprecipitation from PLA-b-PEG copolymers of various PEG lengths. As PEG content increased in the polymer, we observed a transition from a frozen solid particle structure to a more dynamic particle structure. Skin absorption studies showed that polymer composition influenced drug penetration depending on skin condition (intact or impaired). In intact skin, highly PEGylated NPs achieved the best skin absorption, even if the penetration differences between the NPs were low. In impaired skin, on the contrary, non-PEGylated NPs (PLA NPs) promoted a strong drug deposition. Further investigations revealed that the strong drug accumulation from PLA NPs in impaired skin was mediated by aggregation and sedimentation of NPs due to the release of charged species from the skin. In contrast, the dynamic structure of highly PEGylated NPs promoted wetting of the surface and interactions with skin lipids, improving drug absorption in intact skin. Since NPs structure and surface properties determine the drug penetration mechanisms at the NP-skin interface, this work highlights the importance of properly tuning NPs composition according to skin physiopathology.

Cross-sectional survey on disease severity in Japanese patients with harlequin ichthyosis/ichthyosis: Syndromic forms and quality-of-life analysis in a subgroup

BACKGROUND

Congenital ichthyoses (CIs) adversely affect quality of life (QOL) in patients. However, the effects of CIs on patient QOL have not been studied sufficiently.

OBJECTIVE

To investigate the association between disease severity and QOL in patients with harlequin ichthyosis (HI) and ichthyosis: syndromic forms (ISFs) METHODS: Clinical information of patients with HI and ISFs from 2010 to 2015 were obtained from 100 dermatology departments/divisions of principal institutes/hospitals throughout Japan. We examined the relationship between disease severity and QOL in patients with HI and ISFs. Patients who were aged 8 years or older and participated in a multicenter retrospective questionnaire survey in Japan were assessed by dermatology life quality index (DLQI, range of 0-30) and clinical ichthyosis score (range of 0-100).

RESULTS

Netherton syndrome patients had a significantly higher risk of allergy to food or environmental allergens than patients with other phenotypes. Keratitis-ichthyosis-deafness (KID) syndrome patients showed a significantly higher risk of skin infections than patients with other phenotypes. Complete data on DLQI were obtained from 13 patients, whose median age was 21 (8-71) years. Nine patients were male, and 4 were female. Systemic retinoids were administrated to 2 of the 3 HI patients. The Spearman's correlation coefficient between the clinical ichthyosis score and DLQI was 0.611 (P < 0.05).

CONCLUSION

We confirmed that Netherton syndrome and KID syndrome patients have a higher risk of allergy to food or environmental allergens and of skin infections, respectively. QOL impairment correlates with disease severity in HI and ISFs patients.

Juvenile Open Angle Glaucoma With Nonbullous Congenital Ichthyosiform Erythroderma

INTRODUCTION

Glaucoma in patients with nonbullous congenital ichthyosiform erythroderma (NBCIE) is a rare entity that has not been described in a histologically confirmed case. We present a unique case of coexisting glaucoma, ichthyosis, and dwarfism that has not been previously described.

METHODS

We present a case of NBCIE with glaucoma and dwarfism that presented to our outpatient department. The patient was referred for watering and photophobia that were due to an epithelial defect that was subsequently managed conservatively. Investigations revealed the existence of a constellation of findings that are presented here.

RESULTS

NBCIE, glaucoma, and dwarfism represent a spectrum of diseases that seem to have a syndromic association. More gene linkage-based analysis are, however, needed to further confirm our observations.

CONCLUSIONS

NBCIE, glaucoma, and dwarfism can often occur together and need to be assessed and managed individually. Early diagnosis of this spectrum can help improve patient management and quality of life. Dermatologists must get an ocular examination conducted for icthyoses patients.

Ichthyosis molecular fingerprinting shows profound TH17 skewing and a unique barrier genomic signature

BACKGROUND

Ichthyoses are a group of rare skin disorders lacking effective treatments. Although genetic mutations are progressively delineated, comprehensive molecular phenotyping of ichthyotic skin could suggest much-needed pathogenesis-based therapy.

OBJECTIVE

We sought to profile the molecular fingerprint of the most common orphan ichthyoses.

METHODS

Gene, protein, and serum studies were performed on skin and blood samples from 29 patients (congenital ichthyosiform erythroderma, n = 9; lamellar ichthyosis, n = 8; epidermolytic ichthyosis, n = 8; and Netherton syndrome, n = 4), as well as age-matched healthy control subjects (n = 14), patients with psoriasis (n = 30), and patients with atopic dermatitis (AD; n = 16).

RESULTS

Using criteria of a fold change of greater than 2 and a false discovery rate of less than 0.05, 132 differentially expressed genes were shared commonly among all ichthyoses, including many IL-17 and TNF-α-coregulated genes, which are considered hallmarks of psoriasis (defensin beta 4A, kynureninase, and vanin 3). Although striking upregulation of TH17 pathway genes (IL17F and IL36B/G) resembling that seen in patients with psoriasis was common to all patients with ichthyoses in a severity-related manner, patients with Netherton syndrome showed the greatest T-cell activation (inducible costimulator [ICOS]) and a broader immune phenotype with T_H1/IFN-γ, OASL, and T_H2/IL-4 receptor/IL-5 skewing, although less than seen in patients with AD (all P < .05). Ichthyoses lacked the epidermal differentiation and tight junction alterations of patients with AD (loricrin, filaggrin, and claudin 1) but showed characteristic alterations in lipid metabolism genes (ELOVL fatty acid elongase 3 and galanin), with parallel reductions in extracellular lipids and corneocyte compaction in all ichthyoses except epidermolytic ichthyosis, suggesting phenotypic variations. Transepidermal water loss, a functional barrier measure, significantly correlated with IL-17-regulated gene expression (IL17F and IL36A/IL36B/IL36G).

CONCLUSION

Similar to patients with AD and psoriasis, in whom cytokine dysregulation and barrier impairment orchestrate disease phenotypes, psoriasis-like immune dysregulation and lipid alterations characterize the ichthyoses. These data support the testing of IL-17/IL-36-targeted therapeutics for patients with ichthyosis similar to those used in patients with psoriasis.

Inherited Nonsyndromic Ichthyoses: An Update on Pathophysiology, Diagnosis and Treatment

Hereditary ichthyoses are due to mutations on one or both alleles of more than 30 different genes, mainly expressed in the upper epidermis. Syndromic as well as nonsyndromic forms of ichthyosis exist. Irrespective of etiology, virtually all types of ichthyosis exhibit a defective epidermal barrier that constitutes the driving force for hyperkeratosis, skin scaling, and inflammation. In nonsyndromic forms, these features are most evident in severe autosomal recessive congenital ichthyosis (ARCI) and epidermolytic ichthyosis, but to some extent also occur in the common type of non-congenital ichthyosis. A correct diagnosis of ichthyosis-essential not only for genetic counseling but also for adequate patient information about prognosis and therapeutic options-is becoming increasingly feasible thanks to recent progress in genetic knowledge and DNA sequencing methods. This paper reviews the most important aspects of nonsyndromic ichthyoses, focusing on new knowledge about the pathophysiology of the disorders, which will hopefully lead to novel ideas about therapy.

X-linked ichthyosis associated with psychosis and behavioral abnormalities: a case report

Background

X-linked ichthyosis is a dermatological condition caused by deficiency for the enzyme steroid sulfatase. Previously, X-linked ichthyosis/steroid sulfatase deficiency has been associated with developmental and neurological phenotypes. Here, we show for the first time, that X-linked ichthyosis may be comorbid with an additional psychiatric phenotype (psychosis).

Case presentation

We report the case of an 11-year-old Saudi Arabian boy with X-linked ichthyosis associated with psychosis, mental retardation, autism spectrum disorder, inattentive attention deficit hyperactivity disorder, and epilepsy. Genetic analysis revealed a 1.68 Mb deletion encompassing STS in 95% of cells while biochemical analysis revealed correspondingly low steroid sulfatase activity consistent with a diagnosis of X-linked ichthyosis. The psychotic symptoms could be reasonably well controlled by administration of an atypical antipsychotic.

Conclusions

This report describes a case of comorbid X-linked ichthyosis and psychosis (most closely corresponding to early-onset schizophrenia) for the first time, and suggests that deficiency for steroid sulfatase and contiguous genes may increase vulnerability to psychosis as well as other psychological disorders.