RESUMEN

BACKGROUND: Ichthyosis is a common keratotic skin disease with high clinical, etiological and genetic heterogeneity. There are four types of non-syndromic hereditary ichthyoses, among which autosomal recessive congenital ichthyosis (ARCI) is a heterogeneous group of recessive Mendelian disorders. ARCI present with different phenotypes and ABCA12 pathogenic variants have been shown to cause complex ARCI phenotypes, including harlequin ichthyosis (HI), lamellar ichthyosis (LI) and congenital ichthyosiform erythroderma (CIE). METHODS: A sporadic male patient, clinically diagnosed with CIE, was enrolled in this study. Exome sequencing was combined with Sanger sequencing to confirm the diagnosis and identify the pathogenic variants. In silico predictions were made using multiple software programs, and the identified variants were interpreted using the ACMG guidelines. A review of all literature reported ABCA12 variants was performed to explore genotype-phenotype correlations. RESULTS: Compound heterozygous ABCA12 variants [c.5381+1G>A and c.5485G>C (p.Asp1829His)] (NM_173076) were identified. The two variants were not detected in the public database. c.5381+1G>A is predicted to affect ABCA12 mRNA splicing and Asp1829 is highly conserved among various species. In silico analysis suggested that these two variants were responsible for the phenotype of the patient. Genotype-phenotype correlation analysis showed that biallelic truncation variants and/or exon/amino acid deletions in ABCA12 are the most common causes of HI. Biallelic missense variants are most common in LI and CIE. CONCLUSIONS: The compound heterozygous ABCA12 variants caused the CIE phenotype observed in the patient. The spectrum of ABCA12 pathogenic variants were broaden. Genotype-phenotype correlation analysis provided detailed evidence which can be used in future prenatal diagnosis and can inform the need for genetic counselling for patients with ABCA12-related ARCIs.

Asunto(s)

Transportadoras de Casetes de Unión a ATP , Heterocigoto , Eritrodermia Ictiosiforme Congénita , Fenotipo , Humanos , Masculino , Transportadoras de Casetes de Unión a ATP/genética , Pueblos del Este de Asia , Estudios de Asociación Genética , Eritrodermia Ictiosiforme Congénita/genética , Eritrodermia Ictiosiforme Congénita/patología , Mutación , Mutación Missense

RESUMEN

Key Clinical Message: High-dose intravenous immunoglobulin exhibits great potential in the treatment of Netherton syndrome. Abstract: Netherton syndrome (NS) is a rare autosomal recessive genodermatosis (OMIM #256500) characterized by superficial scaling, atopic manifestations, and multisystemic complications. It is caused by loss-of-function mutations in the SPINK5 gene, which encode a key kallikrein protease inhibitor. There are two subtypes of the syndrome that differ in clinical presentation and immune profile: ichthyosiform erythroderma and ichthyosis linearis circumflexa. NS is a multisystemic disease with numerous extracutaneous manifestations. Current therapy for patients with NS is mainly supportive, as there is no curative or specific treatment, especially for children with NS, but targeted therapies are being developed. We describe an 8-year-old boy with genetically proven NS treated with intravenous immunoglobulin for recurrent skin and systemic infections from infancy, growth retardation, and associated erythroderma. Under this therapy, his skin status, infectious exacerbations, and quality of life all improved. Knowledge of the cytokine-mediated pathogenesis of NS and the development of new biologic drugs open new possibilities for NS patients. However, the different therapeutic options have been applied in a limited number of cases, and variable responses have been shown. Randomized controlled trials with a sufficient number of patients stratified and treated according to their specific immune profile and clinical phenotype are needed to evaluate the safety and efficacy of treatment options for patients with NS.

RESUMEN

Autosomal recessive congenital ichthyoses (ARCI) is a genetically heterogeneous condition that can be caused by pathogenic variants in at least 12 genes, including ABCA12. ARCI mainly consists of congenital ichthyosiform erythroderma (CIE), lamellar ichthyosis (LI) and harlequin ichthyosis (HI). The objective was to determine previously unreported pathogenic variants in ABCA12 and to update genotype-phenotype correlations for patients with pathogenic ABCA12 variants. Pathogenic variants in ABCA12 were detected using Sanger sequencing or a combination of Sanger sequencing and whole-exome sequencing. To verify the pathogenicity of a previously unreported large deletion and intron variant, cDNA analysis was performed using total RNA extracted from hair roots. Genetic analyses were performed on the patients with CIE, LI, HI and non-congenital ichthyosis with unusual phenotypes (NIUP), and 11 previously unreported ABCA12 variants were identified. Sequencing of cDNA confirmed the aberrant splicing of the variant ABCA12 in the patients with the previously unreported large deletion and intron variant. Our findings expand the phenotype spectrum of ichthyosis patients with ABCA12 pathogenic variants. The present missense variants in ABCA12 are considered to be heterogenous in pathogenicity, and they lead to varying disease severities in patients with ARCI and non-congenital ichthyosis with unusual phenotypes (NIUP).

Asunto(s)

Eritrodermia Ictiosiforme Congénita , Ictiosis Lamelar , Ictiosis , Humanos , Ictiosis Lamelar/genética , Ictiosis Lamelar/patología , ADN Complementario , Genes Recesivos , Mutación , Ictiosis/genética , Eritrodermia Ictiosiforme Congénita/genética , Estudios de Asociación Genética , Transportadoras de Casetes de Unión a ATP/genética

RESUMEN

BACKGROUND: Autosomal recessive congenital ichthyoses (ARCIs) are a clinically heterogeneous group of keratinization disorders characterized by generalized skin scaling due to mutations in at least 12 genes. The aim of our study was to assess disease severity, phenotypic, and ultrastructural features and to evaluate their association with genetic findings in ARCI patients. METHODS: Clinical signs and symptoms, and disease severity were scored in a single-center series of patients with a genetic diagnosis of ARCI. Skin ultrastructural findings were reviewed. RESULTS: Seventy-four consecutive patients (mean age 11.0 years, range 0.1-48.8) affected with lamellar ichthyosis (50/74, 67.5%), congenital ichthyosiform erythroderma (18/74, 24.3%), harlequin ichthyosis (two/74, 2.7%), and other minor ARCI subtypes (four/74, 5.4%) were enrolled. Mutated genes were as follows: TGM1 in 18/74 (24.3%) patients, ALOX12B in 18/74 (24.3%), CYP4F22 in 12/74 (16.2%), ABCA12 in nine/74 (12.2%), ALOXE3 in seven/74 (9.5%), NIPAL4 in seven/74 (9.5%), and CERS3, PNPLA1, and SDR9C7 in 1 patient each (1.4%). Twenty-five previously undescribed mutations in the different ARCI causative genes, as well as two microduplications in TGM1, and two microdeletions in CYP4F22 and NIPAL4 were identified. The mean ichthyosis severity score in TGM1- and ABCA12-mutated patients was significantly higher than in all other mutated genes, while the lowest score was observed in CYP4F22-mutated patients. Alopecia, ectropion, and eclabium were significantly associated with TGM1 and ABCA12 mutations, and large, thick, and brownish scales with TGM1 mutations. Among specific phenotypic features, psoriasis-like lesions as well as a trunk reticulate scale pattern and striated keratoderma were present in NIPAL4-mutated patients. Ultrastructural data available for 56 patients showed a 100% specificity of cholesterol clefts for TGM1-mutated cases and revealed abnormal lamellar bodies in SDR9C7 and CERS3 patients. CONCLUSION: Our study expands the phenotypic and genetic characterization of ARCI by the description of statistically significant associations between disease severity, specific clinical signs, and different mutated genes. Finally, we highlighted the presence of psoriasis-like lesions in NIPAL4-ARCI patients as a novel phenotypic feature with diagnostic and possible therapeutic implications.

Asunto(s)

Eritrodermia Ictiosiforme Congénita , Ictiosis Lamelar , Lipasa , Mutación , Fenotipo , Índice de Severidad de la Enfermedad , Transglutaminasas , Humanos , Niño , Preescolar , Masculino , Femenino , Adolescente , Adulto , Adulto Joven , Lactante , Persona de Mediana Edad , Eritrodermia Ictiosiforme Congénita/genética , Eritrodermia Ictiosiforme Congénita/patología , Italia , Estudios Transversales , Ictiosis Lamelar/genética , Ictiosis Lamelar/patología , Transglutaminasas/genética , Lipasa/genética , Proteínas de la Membrana/genética , Transportadoras de Casetes de Unión a ATP/genética , Genotipo , Araquidonato 12-Lipooxigenasa/genética , Piel/patología , Piel/ultraestructura , Ictiosis/genética , Ictiosis/patología , Fosfolipasas , Receptores de Superficie Celular , Aciltransferasas , Esfingosina N-Aciltransferasa , Sistema Enzimático del Citocromo P-450 , Oxidorreductasas , Lipooxigenasa

RESUMEN

Autosomal recessive congenital ichthyosis (ARCI) is a non-syndromic congenital disorder of cornification characterized by abnormal scaling of the skin. The three major phenotypes are lamellar ichthyosis, congenital ichthyosiform erythroderma, and harlequin ichthyosis. ARCI is caused by biallelic mutations in ABCA12, ALOX12B, ALOXE3, CERS3, CYP4F22, NIPAL4, PNPLA1, SDR9C7, SULT2B1, and TGM1. The most severe form of ARCI, harlequin ichthyosis, is caused by mutations in ABCA12. Mutations in this gene can also lead to congenital ichthyosiform erythroderma or lamellar ichthyosis. We present a large cohort of 64 patients affected with ARCI carrying biallelic mutations in ABCA12. Our study comprises 34 novel mutations in ABCA12, expanding the mutational spectrum of ABCA12-associated ARCI up to 217 mutations. Within these we found the possible mutational hotspots c.4541G>A, p.(Arg1514His) and c.4139A>G, p.(Asn1380Ser). A correlation of the phenotype with the effect of the genetic mutation on protein function is demonstrated. Loss-of-function mutations on both alleles generally result in harlequin ichthyosis, whereas biallelic missense mutations mainly lead to CIE or LI.

Asunto(s)

Eritrodermia Ictiosiforme Congénita , Ictiosis Lamelar , Humanos , Ictiosis Lamelar/genética , Genes Recesivos , Mutación , Eritrodermia Ictiosiforme Congénita/genética , Estudios de Asociación Genética , Transportadoras de Casetes de Unión a ATP/genética , Aciltransferasas/genética , Fosfolipasas/genética

RESUMEN

Self-healing collodion baby (SHCB), also called "self-improving collodion baby", is a rare mild variant of autosomal recessive congenital ichthyosis and is defined as a collodion baby who shows the nearly complete resolution of scaling within the first 3 months to 1 year of life. However, during the neonatal period, it is not easy to distinguish SHCB from other inflammatory forms of autosomal recessive congenital ichthyosis, such as congenital ichthyosiform erythroderma. Here, we report a case study of two Japanese SHCB patients with compound heterozygous mutations, c.235G>T (p.(Glu79∗))/ c.1189C>T (p.(Arg397Cys)) and c.1295A>G (p.(Tyr432Cys))/ c.1138delG (p.(Asp380Thrfs∗3)), in CYP4F22, which encodes cytochrome P450, family 4, subfamily F, polypeptide 22 (CYP4F22). Immunohistochemically, inflammation with the strong expression of IL-17C, IL-36γ, and TNF-α was seen in the skin at birth. CYP4F22 is an ultra-long-chain FA ω-hydroxylase responsible for ω-O-acylceramide (acylceramide) production. Among the epidermal ceramides, acylceramide is a key lipid in maintaining the epidermal permeability barrier function. We found that the levels of ceramides with ω-hydroxy FAs including acylceramides and the levels of protein-bound ceramides were much lower in stratum corneum samples obtained by tape stripping from SHCB patients than in those from their unaffected parents and individuals without SHCB. Additionally, our cell-based enzyme assay revealed that two mutants, p.(Glu79∗) and p.(Arg397Cys), had no enzyme activity. Our findings suggest that genetic testing coupled with noninvasive ceramide analyses using tape-stripped stratum corneum samples might be useful for the early and precise diagnosis of congenital ichthyoses, including SHCB.

Asunto(s)

Ceramidas , Ictiosis Lamelar , Lactante , Recién Nacido , Humanos , Colodión , Ceramidas/metabolismo , Ictiosis Lamelar/diagnóstico , Ictiosis Lamelar/genética , Pruebas Genéticas

RESUMEN

Netherton syndrome (NS, OMIM #256500) is a rare autosomal recessive disease characterized by a triad of congenital ichthyosiform erythroderma (CIE) or ichthyosis linearis circumflexa (ILC), trichorrhexis invaginata (TI), and atopic predisposition. The disease is caused by a mutation in the SPINK5 gene (serine protease inhibitor of Kazal type 5) encoding LEKTI (lymphoepithelial Kazal type-related inhibitor). We performed whole-exome sequencing on one Chinese NS family and made genotype-phenotype correlation analysis on the patients clinically diagnosed with NS or congenital ichthyosis erythroderma. We identified a novel frameshift mutation c.2474_2475del (p.Glu825Glyfs*2) in the SPINK5 gene. The N-terminal mutations of LEKTI cause a severer phenotype, while the C-terminal mutations of LEKT1 are related to a milder phenotype. Our findings suggest that Netherton syndrome may be underestimated clinically, and our findings further expand the reservoir of SPINK5 mutations in Netherton syndrome.

RESUMEN

BACKGROUND: Autosomal recessive congenital ichthyosis (ARCI) refers to non-syndromic ichthyosis caused by mutations in one of the 13 identified genes. There are limited data on the genotype of ARCI and its phenotypic correlation from India. OBJECTIVES: The aim of this study was to characterize the genotype of ARCI among patients from the Indian subcontinent. METHODS: Twenty-eight patients clinically diagnosed as ARCI were recruited prospectively from September 2017 to June 2019 (21 months). DNA was extracted from peripheral blood and analyzed for the 13 described ARCI genes-TGM1, ABCA12, ALOX12B, ALOXE3, CERS3, CYP4F22, LIPN, NIPAL4, PNPLA1, SDR9C7, SLC27A4, SULT2B1, and CASP14 by next-generation sequencing using an in-house panel. The variants identified were confirmed by Sanger sequencing and compared with known pathogenic variants to establish pathogenicity. We also attempted to correlate the phenotype with the genotype. RESULTS: Among the 28 patients recruited (M = 17, F = 11), we identified phenotypes of congenital ichthyosiform erythroderma in 12 (42.9%), 8 with lamellar ichthyosis (28.6%), 5 with intermediate phenotype (17.9%), and 3 with bathing suit ichthyosis (10.7%). Pathogenic and likely pathogenic variants were identified in 22 (78.6%) patients, involving 7 out of the 13 known ARCI genes while 6 (21.4%) did not have pathogenic variants. These included TGM1 mutation in 6 (21.4%), ALOX12B and ALOXE3 in 4 (14.3%) each, NIPAL4 and PNPLA1 in 3 (10.7%) each, and ABCA12 and CERS3 in 1 (3.6%) patient each. Previously unknown pathogenic variants were found in 59.1 % of patients. CONCLUSIONS: Our patients with ARCI were found to have genotypes as previously described in other populations.

Asunto(s)

Eritrodermia Ictiosiforme Congénita , Ictiosis Lamelar , Ictiosis , Aciltransferasas , Proteínas de Transporte de Ácidos Grasos/genética , Genes Recesivos , Genotipo , Humanos , Eritrodermia Ictiosiforme Congénita/diagnóstico , Eritrodermia Ictiosiforme Congénita/genética , Ictiosis Lamelar/diagnóstico , Ictiosis Lamelar/genética , Lipasa , Mutación , Fenotipo , Centros de Atención Terciaria

Asunto(s)

Ictiosis Lamelar , Ictiosis , Humanos , Ictiosis/genética

RESUMEN

Objective:To detect gene mutations in 3 Chinese families with congenital ichthyosiform erythroderma.Methods:Exome sequencing of peripheral blood DNA was performed for 3 probands clinically diagnosed with congenital ichthyosiform erythroderma by using a gene panel targeting hereditary skin diseases to identify mutation sites. Primers were designed according to the mutation sites for PCR amplification, and Sanger sequencing was performed to verify the mutations in probands and other family members in order to identify the cause of the disease.Results:The probands 1 and 2 presented with generalized skin dryness and scaling, and polygonal dark brown scales on the extensor aspect of the lower limbs; the proband 3 mainly presented with well-circumscribed erythema, papules and scales scattered on the trunk and extremities. All probands denied family history of similar diseases. Genetic testing showed that the proband 1 carried compound heterozygous mutations c.100G>A and c.377G>A in the PNPLA1 gene, which were inherited from her mother and father respectively; the proband 2 carried compound heterozygous mutations c.320T>A and c.434T>C in the PNPLA1 gene, which were inherited from her mother and father respectively; a homozygous mutation c.1300delG was identified in the PNPLA1 gene in the proband 3. The mutations co-segregated with the disease phenotypes in the two families with compound heterozygous mutations. Among the 5 identified mutations, the two missense mutations (c.377G>A and c.320T>A) were firstly reported.Conclusion:Biallelic mutations in the PNPLA1 gene are the causative mutations responsible for autosomal recessive congenital ichthyosis in the three probands, and the newly reported mutations expand the mutation spectrum in the disease.

RESUMEN

Netherton syndrome (NS) is an autosomal recessive primary immunodeficiency. It is characterised by substantial skin barrier defects and is often misdiagnosed as severe atopic dermatitis or hyper-immunoglobulin E syndrome. Although more than 80 NS-associated pathogenic mutations in the serine peptidase inhibitor kazal type 5 (SPINK5) gene have been reported worldwide, only one has been reported in the Arab population to date. We report the case of a novel association between the c.1887+1G>A mutation in the SPINK5 gene and NS in an Omani-Arab patient born in 2014 who was managed at a paediatric immunology clinic in Muscat, Oman. Accurate genetic diagnosis facilitated tailored clinical management of the index patient and enabled the provision of genetic counselling and offering of future reproductive options to the individuals related to the index patient.

Asunto(s)

Síndrome de Netherton , Niño , Humanos , Mutación , Síndrome de Netherton/diagnóstico , Síndrome de Netherton/genética , Omán , Proteínas Inhibidoras de Proteinasas Secretoras/genética , Inhibidor de Serinpeptidasas Tipo Kazal-5/genética

RESUMEN

Trichorrhexis invaginata and ichthyosiform erythroderma are pathognomic for Netherton Syndrome.

RESUMEN

BACKGROUND: Autosomal recessive congenital ichthyoses (ARCI) are a genetically heterogeneous group of rare and chronic disorders characterized by generalized skin scaling and hyperkeratosis, erythroderma, and palmoplantar keratoderma. Additional features include ectropion, eclabium, ear deformities, foul-smell, joints contractures and walking problems, recurrent infections, as well as pruritus and pain. No curative therapy is available and disease care mainly relies on daily application of topical emollients and keratolytics to the whole-body surface. Altogether, disease signs and symptoms and treatment modalities have a major impact on quality of life of patients and their caregivers. However, very few studies have evaluated the family disease burden in ARCI. METHODS: We have performed an Italian multicenter cross-sectional study to assess the secondary disease impact on family members of pediatric and adult patients with ARCI, using a validated dermatology-specific questionnaire, the family dermatology life quality index (FDLQI). Disease severity was assessed by the dermatologist in each center. RESULTS: Seventy-eight out of 82 patients who were accompanied by at least one family member filled the FDLQI. Forty-eight (61.5%) patients were aged less than 18 years. The mean FDLQI score was 10.3 (median 10), and the most affected dimensions were (1) time needed for care, (2) extra-housework, and (3) household expenditure. Higher total FDLQI score significantly correlated with more severe disease score (P = 0.003). Features associated with greater family burden included recurrent infections (P = 0.004), foul-smell (P = 0.009), palmoplantar keratoderma (P = 0.041), but also presence of scales on the face (P = 0.039) and ear deformities (P = 0.016). CONCLUSIONS: Our findings highlight the major socio-economic and psychological burden imposed by ARCI on the QoL of family caregivers. In addition, they show that global evaluation of disease impact also on family members is an essential part of patient-reported outcomes. Finally, our data underline the need to develop specific measures for family support.

Asunto(s)

Eritrodermia Ictiosiforme Congénita , Ictiosis Lamelar , Queratodermia Palmoplantar , Adulto , Niño , Estudios Transversales , Humanos , Calidad de Vida

RESUMEN

Autosomal recessive congenital ichthyoses (ARCI) are characterized by generalized skin scaling, hyperkeratosis, erythroderma, and disabling features affecting the skin (palmoplantar keratoderma, fissures, pain, itch), eyes, ears, and joints. Disease severity and chronicity, patient disfigurement, and time and costs required for care impose a major burden on quality of life. This multicentre cross-sectional study investigated the impact of ARCI on quality of life of patients and families, using the Dermatology Life Quality Index (DLQI), the Children DLQI (CDLQI) and Family Burden of Ichthyosis (FBI) questionnaires. Disease severity was assessed by a dermatologist. A total of 94 patients were recruited, of whom 52 (55.3%) children. Mean age was 20.1 (median 13.5) years. The mean CDLQI/DLQI score was 7.8, and 21 patients scored >10, indicating a major impairment in quality of life: symptoms, feelings and treatment problems were the most affected domains of quality of life. FBI showed a major repercussion on psychological factors and work. The results of this study highlight the impact of ARCI on specific aspects of patient and family life, underlining the need for psychological support.

Asunto(s)

Eritrodermia Ictiosiforme Congénita , Ictiosis Lamelar , Ictiosis , Adulto , Niño , Estudios Transversales , Humanos , Eritrodermia Ictiosiforme Congénita/diagnóstico , Eritrodermia Ictiosiforme Congénita/epidemiología , Eritrodermia Ictiosiforme Congénita/genética , Ictiosis/diagnóstico , Ictiosis/epidemiología , Ictiosis/genética , Ictiosis Lamelar/diagnóstico , Ictiosis Lamelar/genética , Ictiosis Lamelar/terapia , Italia/epidemiología , Calidad de Vida , Adulto Joven

RESUMEN

Autosomal recessive congenital ichthyosis (ARCI) is a rare and heterogeneous skin cornification disorder presenting with generalized scaling and varying degrees of erythema. Clinical manifestations range from lamellar ichthyosis (LI), congenital ichthyosiform erythroderma (CIE) through the most severe form of ARCI, Harlequin ichthyosis (HI). We used homozygosity mapping, whole-exome and direct sequencing to delineate the relative distribution of pathogenic variants as well as identify genotype-phenotype correlations in a cohort of 62 Middle Eastern families with ARCI of various ethnic backgrounds. Pathogenic variants were identified in most ARCI-associated genes including TGM1 (21%), CYP4F22 (18%), ALOX12B (14%), ABCA12 (10%), ALOXE3 (6%), NIPAL4 (5%), PNPLA1 (3%), LIPN (2%) and SDR9C7 (2%). In 19% of cases, no mutation was identified. Our cohort revealed a higher prevalence of CYP4F22 and ABCA12 pathogenic variants and a lower prevalence of TGM1 and NIPAL4 variants, as compared to data obtained in other regions of the world. Most variants (89%) in ALOX12B were associated with CIE and were the most common cause of ARCI among patients of Muslim origin (26%). Palmoplantar keratoderma associated with fissures was exclusively a result of pathogenic variants in TGM1. To our knowledge, this is the largest cohort study of ARCI in the Middle-Eastern population reported to date. Our data demonstrate the importance of population-tailored mutation screening strategies and shed light upon specific genotype-phenotype correlations.

Asunto(s)

Eritrodermia Ictiosiforme Congénita/epidemiología , Eritrodermia Ictiosiforme Congénita/genética , Estudios de Cohortes , Genotipo , Humanos , Medio Oriente/epidemiología , Epidemiología Molecular , Mutación , Fenotipo

RESUMEN

Objective:To detect gene mutations and make a diagnosis in a family with ichthyosis accompanied by liver injury.Methods:Clinical data were collected from the proband, and genomic DNA was extracted from peripheral blood samples from the proband and his parents. Exome sequencing was performed in the proband by using a gene panel targeting hereditary skin diseases to identify mutation sites, and then the candidate mutation site was verified by PCR and Sanger sequencing in the family members. Results of peripheral blood smear examination and other auxiliary examinations were collected from the proband and his parents and analyzed.Results:The proband presented with generalized dry skin and tiny white scales on the lower limbs, accompanied by elevated transaminase levels, mild sensorineural hearing loss in both ears and fatty liver. Exome sequencing revealed a homozygous mutation c.933dupA in exon 6 of the ABHD5 gene encoding CGI-58 protein in the peripheral blood genomic DNA of the proband, resulting in a frameshift mutation p.R312Tfs*45 in the amino acid sequence. Heterozygous mutations at this site were identified in his father and mother. The mutation cosegregated with the disease phenotype in the family. The peripheral blood smear examination of the proband showed lipid vacuoles in neutrophils, which were called Jordan anomaly. Conclusion:The diagnosis of Chanarin-Dorfman syndrome was made in the proband based on the presentation of ichthyosis-like skin lesions and abnormal liver function, as well as the homozygous mutation in the ABHD5 gene and Jordan anomaly in peripheral blood smears.

RESUMEN

Autosomal recessive congenital ichthyoses (ARCI) are rare genodermatosis disorders characterized by phenotypic and genetic heterogeneity. At least fourteen genes so far have been related to ARCI; however, despite genetic heterogeneity, phenotypes associated with mutation of different ARCI genes may overlap, thereby making difficult their clinical and molecular classification. In addition, molecular tests for diagnosis of such an extremely rare heterogeneous inherited disease are not easily available in clinical settings. In the attempt of identifying the genetic cause of the disease in four Italian patients with ARCI, we performed next-generation sequencing (NGS) analysis targeting 4811 genes that have been previously linked to human genetic diseases; we focused our analysis on the 13 known ARCI genes comprised in the panel. Nine different variants including three novel small nucleotide changes and two novel large deletions have been identified and validated in the ABCA12, ALOX12B, CYP4F22, and SULT2B1 genes. Notably, two patients had variants in more than one gene. The identification and validation of new pathogenic ABCA12, ALOX12B, CYP4F22, and SULT2B1 variants through multi-gene NGS in four cases of ARCI further highlight the importance of these genes in proper skin function and development.