Netherton syndrome-A therapeutic challenge in childhood.

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.

Orofacial Anomalies in Kindler Epidermolysis Bullosa.

Importance: Kindler epidermolysis bullosa is a genetic skin-blistering disease associated with recessive inherited pathogenic variants in FERMT1, which encodes kindlin-1. Severe orofacial manifestations of Kindler epidermolysis bullosa, including early oral squamous cell carcinoma, have been reported. Objective: To determine whether hypoplastic pitted amelogenesis imperfecta is a feature of Kindler epidermolysis bullosa. Design, Settings, and Participants: This longitudinal, 2-center cohort study was performed from 2003 to 2023 at the Epidermolysis Bullosa Centre, University of Freiburg, Germany, and the Special Care Dentistry Clinic, University of Chile in association with DEBRA Chile. Participants included a convenience sampling of all patients with a diagnosis of Kindler epidermolysis bullosa. Main Outcomes and Measures: The primary outcomes were the presence of hypoplastic pitted amelogenesis imperfecta, intraoral wounds, gingivitis and periodontal disease, gingival hyperplasia, vestibular obliteration, cheilitis, angular cheilitis, chronic lip wounds, microstomia, and oral squamous cell carcinoma. Results: The cohort consisted of 36 patients (15 female [42%] and 21 male [58%]; mean age at first examination, 23 years [range, 2 weeks to 70 years]) with Kindler epidermolysis bullosa. The follow-up ranged from 1 to 24 years. The enamel structure was assessed in 11 patients, all of whom presented with enamel structure abnormalities. The severity of hypoplastic pitted amelogenesis imperfecta varied from generalized to localized pitting. Additional orofacial features observed include gingivitis and periodontal disease, which was present in 90% (27 of 30 patients) of those assessed, followed by intraoral lesions (16 of 22 patients [73%]), angular cheilitis (24 of 33 patients [73%]), cheilitis (22 of 34 patients [65%]), gingival overgrowth (17 of 26 patients [65%]), microstomia (14 of 25 patients [56%]), and vestibular obliteration (8 of 16 patients [50%]). Other features included chronic lip ulcers (2 patients) and oral squamous cell carcinoma with lethal outcome (2 patients). Conclusions and Relevance: These findings suggest that hypoplastic pitted amelogenesis imperfecta is a feature of Kindler epidermolysis bullosa and underscore the extent and severity of oral manifestations in Kindler epidermolysis bullosa and the need for early and sustained dental care.

Netherton Syndrome with a Novel Likely Pathogenic Variant c.420del (p.Ser141ProfsTer5) in SPINK5 Gene: A Case Report.

Introduction: Netherton syndrome (NS) is a rare autosomal recessive genodermatosis in the group of congenital ichthyosis. The clinical manifestations of the syndrome vary from a very mild clinical manifestation occurring with the picture of ichthyosis linearis circumflexa to exfoliative erythroderma. It can be fatal in the first days of a newborn's life due to dehydration, hypothermia, weight loss, respiratory infections, and sepsis. A specific anomaly of the hair trichorrexis invaginata is considered pathognomonic for the syndrome. Genetic testing of SPINK5 gene is key to confirming the diagnosis and starting early treatment. Case Presentation: We present a case report of NS in a 6-year-old boy who suffered from generalized erythroderma and desquamation of the skin from birth. The patient has atopic diathesis, recurrent skin infections, increased levels of IgE, and delayed physical development. Two genetic variants in SPINK5 gene with clinical significance were identified. The first detected variant is a nonsense mutation, predicted to cause loss of normal protein function either by protein truncation or by nonsense-mediated mRNA decay. The second variant is a likely pathogenic frameshift mutation that truncates the protein in 5 amino acids. The child was treated with acitretin, without satisfactory effect. Conclusion: The genetic variant we have described correlates with a severe clinical phenotype of NS. The second genetic variant of the SPINK5 gene, inherited from the father in our case, is novel and has never been published in the literature.

Initial validation of the epidermolysis bullosa-specific module of the Infants and Toddlers Dermatology Quality of Life questionnaire.

Children with epidermolysis bullosa (EB) experienced the highest quality of life impact among several skin conditions and have problems which had not been reported by parents of children with other skin diseases. The EB-specific module of the Infants and Toddlers Dermatology Quality of Life (InToDermQoL) questionnaire was recently developed to measure the impact of disease-specific aspects in children from birth to the age of 4 years. The aim of this study was initial validation of the InToDermQoL-EB questionnaire. Parents of 44 children with EB from seven countries completed the InToDermQoL-EB questionnaire. Cronbach's alpha was .86, .89 and .91 for three age-specific versions. Differences between severity levels were all significant except for that between moderate and severe level in the version for 3- to 4-year-old children. All items of the three versions of the InToDermQoL-EB showed very high levels of relevance except "problems with defecation" in children younger than 1 year and "rejection by other children" in 3- to 4-year-old children. The three versions of the InToDermQoL-EB instrument showed good internal consistency and discriminated well between different severity levels. All InToDermQoL-EB items were confirmed as being of high relevance and the questionnaire may be used in practice and clinical trials.

Assessment of the risk and characterization of non-melanoma skin cancer in Kindler syndrome: study of a series of 91 patients.

BACKGROUND: Kindler Syndrome (KS) is a rare genodermatosis characterized by skin fragility, skin atrophy, premature aging and poikiloderma. It is caused by mutations in the FERMT1 gene, which encodes kindlin-1, a protein involved in integrin signalling and the formation of focal adhesions. Several reports have shown the presence of non-melanoma skin cancers in KS patients but a systematic study evaluating the risk of these tumors at different ages and their potential outcome has not yet been published. We have here addressed this condition in a retrospective study of 91 adult KS patients, characterizing frequency, metastatic potential and body distribution of squamous cell carcinoma (SCC) in these patients. SCC developed in 13 of the 91 patients. RESULTS: The youngest case arose in a 29-year-old patient; however, the cumulative risk of SCC increased to 66.7% in patients over 60 years of age. The highly aggressive nature of SCCs in KS was confirmed showing that 53.8% of the patients bearing SCCs develop metastatic disease. Our data also showed there are no specific mutations that correlate directly with the development of SCC; however, the mutational distribution along the gene appears to be different in patients bearing SCC from SCC-free patients. The body distribution of the tumor appearance was also unique and different from other bullous diseases, being concentrated in the hands and around the oral cavity, which are areas of high inflammation in this disease. CONCLUSIONS: This study characterizes SCCs in the largest series of KS patients reported so far, showing the high frequency and aggressiveness of these tumors. It also describes their particular body distribution and their relationship with mutations in the FERMT-1 gene. These data reinforce the need for close monitoring of premalignant or malignant lesions in KS patients.