A homozygous p.Leu813Pro gain-of-function NLRP1 variant causes phenotypes of different severity in two siblings.

BACKGROUND: A trio exome sequencing study identified a previously unreported NLRP1 gene variant resulting in a p.Leu813Pro substitution of the LRR (leucine-rich repeats) domain of the NLRP1 protein (NACHT, LRR and PYD domains-containing protein 1). This homozygous mutation was shared by two sisters with different clinical presentation: the younger sister had generalized inflammatory nodules with keratotic plugs, clinically resembling multiple keratoacanthomas, while the older had manifestations of familial keratosis lichenoides chronica. OBJECTIVES: To analyse the consequences of this NLRP1 variant in two siblings with a different clinical spectrum of severity. METHODS: To demonstrate the pathogenicity, p.Leu813Pro was recombinantly expressed, and its effect on inflammasome assembly was assessed. Exome sequencing and RNA-Seq were performed to identify factors with potentially modifying effects on the severity of the skin manifestation between each sibling. RESULTS: The variant p.Leu813Pro triggered activation of the NLRP1 inflammasome leading to ASC (apoptosis-associated speck-like protein containing a CARD) speck formation and interleukin (IL)-1ß release. The more severely affected sister had several additional genomic variants associated with atopy and psoriasis that were not present in her sibling. IL-5 and IL-17 emerged as dominant cytokines driving prominent inflammation in the skin of the severely affected sibling. CONCLUSIONS: To the best of our knowledge, this is the first report of a NLRP1 variant that leads to a different clinical spectrum of severity within the same sibship. IL-5 and IL-17 were the main cytokines expressed in the inflammatory lesions of the severely affected patient and might be regarded as disease modifying factors, and therefore may be considered as therapeutic targets.

Variable Outcome of Immunotherapy in Advanced Multiple Cutaneous Squamous Cell Carcinomas in Two Patients with Recessive Dystrophic Epidermolysis Bullosa.

Cutaneous squamous cell carcinoma (cSCC) is a major complication of recessive dystrophic epidermolysis bullosa (RDEB) that has high morbidity and mortality rates and unmet therapeutic needs. The aim of this study was to evaluate the molecular pattern of cSCC and the clinical course of immunotherapy in 2 RDEB patients with multiple advanced cSCC. Clinical course and disease staging were evaluated retrospectively. The tumour tissues were subjected to immunohistochemical staining. DNA from the blood and cSCC samples was subjected to massive parallel sequencing, and somatic mutations were determined. Patient 1 survived for over 2 years as disease control was achieved with cemiplimab and intralesional interleukin-2. The target advanced cSCC demonstrated a high rate of somatic mutations and strong expression of the immune markers, indoleamine 2,3-dioxygenase, programmed cell death protein ligand 1, and lymphocyte-activation gene 3. The patient ultimately succumbed to complications of oesophageal carcinoma. Patient 2 had an undifferentiated cSCC on the foot, which displayed a low mutational burden and did not express immune markers. The tumour progressed quickly even with cemiplimab therapy. These 2 cases underscore the challenges of cSCC treatment for RDEB. Multiple tumours with different molecular and immune profiles occur concomitantly or sequentially, and surgical excision is not always possible because of the anatomical and tissue constraints imposed by the disease itself. In conclusion, programmed cell death protein 1 inhibitors are approved and effective in treating metastatic and locally advanced cSCC. Our experience and the literature suggest that cemiplimab is an option in patients with RDEB if surgery is not. Somatic mutations and the immune microenvironment should be characterized to predict therapeutic response, particularly in aggressive undifferentiated tumours.

Interleukin-17A immune pattern across genetic acantholytic and blistering disorders.

There is a high therapeutic need in acantholytic and blistering genodermatoses. Cutaneous inflammation is a reasonable therapeutic target, although the patterns are not yet fully elucidated. Here we investigated by immunohistochemistry whether interleukin (IL)-17A is expressed in the inflammatory infiltrate in 34 patients with Hailey-Hailey disease, Darier disease, and junctional and dystrophic epidermolysis bullosa. There was a 5-7-fold increase in the number of IL-17A-positive cells in all patients' samples as compared with normal skin. IL-17A cells were present in epidermal acantholytic areas and dermal inflammatory infiltrates in Hailey-Hailey and Darier disease. In epidermolysis bullosa samples, positive cells were present at the dermoepidermal junction zone. The IL-17A inflammatory pattern was validated by observing upregulation of downstream genes/proteins, S100A7, S100A8 and S100A9 (S100 calcium-binding proteins). These results suggest that IL-17A contributes to skin inflammation and could be a therapeutic target during inflammatory flares in these disorders.

Acral lamellar ichthyosis with amino acid substitution in the C-terminus of keratin 2.

BACKGROUND: Most cases of hereditary ichthyoses present with generalized scaling and skin dryness. However, in some cases skin involvement is restricted to particular body regions as in acral lamellar ichthyosis. OBJECTIVES: We report on the genetic basis of acral ichthyosis in two families presenting with a similar phenotype. METHODS: Genetic testing was performed by targeted next generation sequencing and whole-exome sequencing. For identity-by-descent analysis, the parents were genotyped and data analysis was performed with the Chromosome Analysis Suite Software. RT-PCR with RNA extracted from skin samples was used to analyse the effect of variants on splicing. RESULTS: Genetic testing identified a few heterozygous variants, but only the variant in KRT2 c.1912 T > C, p.Phe638Leu segregated with the disease and remained the strongest candidate. Pairwise identity-by-descent analysis revealed no indication of family relationship. Phenylalanine 638 is the second last amino acid upstream of the termination codon in the tail of K2, and substitution to leucine is predicted as probably damaging. Assessment of the variant is difficult, in part due to the lack of crystal structures of this region. CONCLUSIONS: Altogether, we show that a type of autosomal dominant acral ichthyosis is most probably caused by an amino acid substitution in the C-terminus of keratin 2.

Phänotypisches und genetisches Spektrum von Incontinentia pigmenti - eine große Fallserie.

HINTERGRUND: Incontinentia pigmenti ist eine seltene X-chromosomal dominant vererbte Systemerkrankung, die vor allem die Haut, aber auch andere neuroektodermale Gewebe wie Zähne, Haare, Augen und das zentrale Nervensystem betrifft. PATIENTEN UND METHODIK: Diese multizentrische Fallserienstudie wurde an drei europäischen Hautkliniken durchgeführt und umfasste 30 Patienten mit Incontinentia pigmenti. Zwanzig Patienten wurden klinisch und genetisch untersucht, weitere zehn nur genetisch. ERGEBNISSE: Die Studie umfasste 28 Frauen und zwei Männer mit einem medianen Alter von drei Jahren. Kutane Manifestationen zeigten sich bei allen 20 Patienten mit klinischen Daten. Stadium I wurde in 90 % dieser Patienten beobachtet. Stadium IV wurde bereits im Alter von einem Jahr beobachtet. Zahn- (81 %), Haar- (78 %) und neurologische Anomalien (53 %) waren häufiger als in bisherigen Berichten. Vierzehn Hautbiopsien zeigten typische Merkmale des entsprechenden Stadiums. Genetische Tests wurden bei 24 Patienten durchgeführt, von denen 14 die häufige Exon 4-10-Deletion und sieben andere pathogene Varianten aufwiesen, darunter drei unveröffentlichte Mutationen. In drei weiteren Fällen wurden keine genetischen Veränderungen gefunden. SCHLUSSFOLGERUNGEN: In dieser Studie reichte der Phänotyp von lediglich subtil ausgeprägter Hautbeteiligung bis hin zu schweren Multisystemerkrankungen. Die extrakutane Beteiligung sollte zum Zeitpunkt der Diagnose und in regelmäßigen Abständen evaluiert werden, da sich einige Manifestationen erst mit der Zeit entwickeln. SUMMARY: Background and objectives Incontinentia pigmenti is a rare X-linked dominantly inherited systemic disease affecting primarily the skin but also other neuroectodermal tissues such as teeth, hair, eyes, and the central nervous system. Patients and methods This multicenter case series study was conducted at three European departments of Dermatology including 30 patients with incontinentia pigmenti. Twenty patients were evaluated clinically and genetically, another ten only genetically. Results The study included 28 females and two males with a median age of three years. Cutaneous manifestations were present in all 20 patients with clinical data. Stage I was observed in 90 % of those patients. Stage IV was observed as early as one year of age. Dental (81 %), hair (78 %) and neurological anomalies (53 %) were more frequent than previously reported. Fourteen skin biopsies showed typical features of the corresponding stage. Genetic testing of 24 patients revealed the common exon 4-10 deletion in 14 cases and seven other pathogenic variants, including three unpublished mutations. In another three cases, no genetic alterations were found. Conclusions In this study, the phenotype ranged from only subtle cutaneous involvement to severe multisystemic disorders. Extracutaneous involvement should be evaluated at the time of diagnosis and in regular intervals, as some manifestations may develop over time.

Phenotypic and genetic spectrum of incontinentia pigmenti - a large case series.

BACKGROUND AND OBJECTIVES: Incontinentia pigmenti is a rare X-linked dominantly inherited systemic disease affecting primarily the skin but also other neuroectodermal tissues such as teeth, hair, eyes, and the central nervous system. PATIENTS AND METHODS: This multicenter case series study was conducted at three European departments of Dermatology including 30 patients with incontinentia pigmenti. Twenty patients were evaluated clinically and genetically, another ten only genetically. RESULTS: The study included 28 females and two males with a median age of three years. Cutaneous manifestations were present in all 20 patients with clinical data. Stage I was observed in 90 % of those patients. Stage IV was observed as early as one year of age. Dental (81 %), hair (78 %) and neurological anomalies (53 %) were more frequent than previously reported. Fourteen skin biopsies showed typical features of the corresponding stage. Genetic testing of 24 patients revealed the common exon 4-10 deletion in 14 cases and seven other pathogenic variants, including three unpublished mutations. In another three cases, no genetic alterations were found. CONCLUSIONS: In this study, the phenotype ranged from only subtle cutaneous involvement to severe multisystemic disorders. Extracutaneous involvement should be evaluated at the time of diagnosis and in regular intervals, as some manifestations may develop over time.

[Granulomatous rosacea in a lung transplant recipient : A possible therapy option in a unique group of patients]. / Granulomatöse Rosazea bei einem Lungentransplantierten : Eine mögliche Therapieoption bei einer besonderen Patientengruppe.

Rosacea, a frequent chronic inflammatory disease of the adnexal structures, is associated with an increased number of demodex mites. In patients with immunosuppression, it can present in fulminant progressions like granulomatous rosacea. In this specific subgroup of patients, treatment is not only complicated by aggressive occurrences, but is also limited by possible drug interactions with immunosuppressive drugs. We present a case of a 66-year-old lung transplant recipient, who was successfully treated with oral metronidazole and ivermectin cream.

Esophageal lichen planus: towards diagnosis of an underdiagnosed disease.

Background: Although lichen planus (LP) is a common skin disorder, the prevalence of esophageal involvement (ELP) and its clinical manifestations are poorly defined. We aimed to establish diagnostic criteria and characterize disease outcomes of ELP.Methods: Clinical, endoscopic, histological, and immunofluorescence data from consecutive patients with known LP between 2013 and 2018 were analyzed. We established endoscopic (denudation and tearing of the mucosa, hyperkeratosis and trachealization) and histological criteria (mucosal detachment, T-lymphocytic infiltrate, intraepithelial apoptosis, dyskeratosis, and fibrinogen deposits along the basement membrane) to grade disease severity. Endoscopic findings were correlated with clinical symptoms. Response to medical therapy was monitored.Results: Fifty-two consecutive patients (median age 59.5 years) were analyzed. According to our grading system, 16 patients were considered as severe and 18 as mild ELP. Dysphagia was the only symptom which differentiated patients with severe (14/16) or mild ELP (8/18) from patients without ELP (1/18). Concomitant oral and genital involvement of LP was associated with the presence of ELP, while oral involvement alone was not. Follow-up of 14/16 patients with severe EPL for at least one year revealed that most of these patients responded to topical corticosteroids (budesonide: n = 9/10 or fluticasone n = 2/2). Three budesonide patients experienced a resolution of symptomatic esophageal stenosis.Conclusions: Esophageal involvement of LP is frequent, but may be asymptomatic. ELP can be diagnosed using the diagnostic criteria proposed here. Dysphagia and combined oral and genital manifestation are associated with ELP. Therapy with topical corticosteroids appears to be a prudent therapeutic approach for ELP.

Eosinophilic dermatosis of hematologic malignancy: Correlation of molecular characteristics of skin lesions and extracutaneous manifestations of hematologic malignancy.

BACKGROUND: Skin diseases are frequent in patients with chronic lymphocytic leukemia (CLL) and other hematological neoplasias. Eosinophilic dermatosis (ED) of hematologic malignancy has long been considered a nonspecific cutaneous reaction pattern. Recently neoplastic cells have been shown to be present in ED, thus challenging the classification as a nonspecific dermatosis. METHODS: We report five patients with ED in association with CLL. We further investigated the presence of neoplastic B-cells in the skin infiltrate by immunohistochemistry and immunoglobulin heavy chain rearrangement and compared these to extracutaneous manifestations of CLL. RESULTS: The phenotype of the lymphocytic infiltrate was predominately CD3+ (range: 60%-90%). CD20+ and CD79a+ lymphocytes were less frequent, accounting for up to 15% (range: absent - 15%). CD23+ lymphocytes represented up to 20% (range: absent - 20%) of the infiltrate. The analysis of the immunoglobulin heavy chain rearrangement in the skin specimens showed clonal rearrangements in 4/5 patients and in three of these four patients clones were identical to extracutaneous CLL manifestations. CONCLUSION: Our data show that neoplastic B-cells are very frequently found in ED when systematically evaluated. This findings support the hypothesis that leukemic cells play a pathogenetic role in ED of hematologic malignancy.

Resources spent on dermatological emergency patients: A twelve-month prospective data collection from Germany.

BACKGROUND AND OBJECTIVES: Rising numbers of patients consulting emergency units are associated with an increased demand for material and personnel. In order to better quantify these resources, we performed an analysis of diagnostic procedures, treatment types, and the quantity and educational level of staff involved in emergency consultations. PATIENTS AND METHODS: The study was conducted as a prospective single-center survey over twelve months in the dermatology unit of a Germany university hospital. 3155 consultations were included by consecutive sampling. RESULTS: Diagnostic tests (e.g. microbiological swab, blood testing, punch biopsy) were performed in 29 % of all consultations. Physicians prescribed treatment in 70 % of cases, with steroids and antihistamines being the most frequent topical and systemic treatment, respectively. Each patient was seen by at least one physician and a nurse, and in 25 % of cases an additional physician was involved. Less than thirty minutes was required for the consultation in the vast majority of cases. On average, emergency consultations required two hours per day of the treating physician's time, not including the time of other involved staff such as nurses and laboratory technicians. CONCLUSIONS: This study demonstrates the extent of resources involved in the treatment of dermatological emergency consultations.

Dermatological conditions presenting to the emergency dermatological unit of a university hospital in Germany.

BACKGROUND AND OBJECTIVES: Recently, there have been increasing numbers of patients consulting emergency units in all medical disciplines. Our aim was to analyze the demographics, referral mode, symptoms, localization of lesions, prior treatment, diagnoses and hospitalization rate of dermatological patients. PATIENT AND METHODS: The study was conducted as a prospective single center survey over six months in the dermatology unit of a university hospital in Germany. 1552 consultations were included with consecutive sampling. RESULTS: The study cohort had a mean age of 41 years and included 53 % females. Nearly half of the patients lived less than 10 kilometers from the study center. 72 % of patients referred themselves. The main symptoms were itching and occurrence of a rash; these symptoms had been present for more than a week on average. A general manifestation was present on the skin in most cases. 55 % of patients were seen by a dermatologist or a general practitioner before the consultation. Prior treatment had been received in 49 % of cases. Eight percent of patients were hospitalized. Eczema was the most common diagnosis, followed by urticaria and scabies. CONCLUSIONS: This study confirms that a considerable number of patients present with non-urgent diagnoses. Careful prescreening and sensitization of the population may be necessary to reverse this trend.

Palmoplantar keratodermas: clinical and genetic aspects.

Palmoplantar keratodermas comprise a diverse group of acquired and hereditary disorders marked by excessive thickening of the epidermis of palms and soles. Early onset and positive family history suggest a genetic cause. While hereditary forms of palmoplantar keratoderma (PPK) may represent the sole or dominant clinical feature, they may also be associated with other ectodermal defects or extracutaneous manifestations. In recent years, much progress has been made in deciphering the genetic basis of PPK, which has led to the emergence of new disorders and syndromes. The elucidation of disease mechanisms has opened new avenues for specific therapies, increasingly sparking interest in this field. Given the high heterogeneity with respect to clinical features, genetic defects, and disease mechanisms, the classification of PPK is based on various criteria. These include extent of disease manifestations, morphology of palmoplantar skin involvement, inheritance patterns, and molecular pathogenesis. Though not always feasible, the clinical distinction of various PPK entities is based on fine-tuned criteria or clues. Remarkably, apparently distinct disorders have been shown to be allelic, as they are caused by mutations in the same gene. By contrast, similar clinical pictures may result from mutations in different genes. Because of this complexity, mutation analysis is required to determine the precise type of PPK. The best-defined entities are described in this review.

Epidermolysis-Bullosa-Associated Squamous Cell Carcinomas Support an Immunosuppressive Tumor Microenvironment: Prospects for Immunotherapy.

Cutaneous squamous cell carcinomas (SCCs) are a major complication of some subtypes of epidermolysis bullosa (EB), with high morbidity and mortality rates and unmet therapeutic needs. The high rate of endogenous mutations and the fibrotic stroma are considered to contribute to the pathogenesis. Patients with dystrophic EB (DEB) and Kindler EB (KEB) have the highest propensity for developing SCCs. Another patient group that develops high-risk SCCs is immunosuppressed (IS) patients, especially after organ transplantation. Herein, we interrogate whether immune checkpoint proteins and immunosuppressive enzymes are dysregulated in EB-associated SCCs as an immune resistance mechanism and compare the expression patterns with those in SCCs from IS patients, who frequently develop high-risk tumors and sporadic SCCs, and immunocompetent (IC) individuals. The expression of indoleamine 2,3-dioxygenase (IDO), programmed cell death protein-1 (PD-1), programmed cell death ligand-1 (PD-L1), T cell immunoglobulin and mucin-domain-containing protein-3 (TIM-3), lymphocyte activation gene-3 (LAG-3), and inflammatory infiltrates (CD4, CD8, and CD68) was assessed via immunohistochemistry and semi-quantitative analysis in 30 DEB-SCCs, 22 KEB-SCCs, 106 IS-SCCs, and 100 sporadic IC-SCCs. DEB-SCCs expressed significantly higher levels of IDO and PD-L1 in tumor cells and PD-1 in the tumor microenvironment (TME) compared with SCCs from IC and IS individuals. The number of CD4-positive T cells per mm2 was significantly lower in DEB-SCCs compared with IC-SCCs. KEB-SCCs showed the lowest expression of the exhaustion markers TIM-3 and LAG-3 compared with all other groups. These findings identify IDO, PD-1, and PD-L1 to be increased in EB-SCCs and candidate targets for combinatory treatments, especially in DEB-SCCs.