DOCK11 deficiency in patients with X-linked actinopathy and autoimmunity.

Dedicator of cytokinesis (DOCK) proteins play a central role in actin cytoskeleton regulation. This is highlighted by the DOCK2 and DOCK8 deficiencies leading to actinopathies and immune deficiencies. DOCK8 and DOCK11 activate CDC42, a Rho-guanosine triphosphate hydrolases involved in actin cytoskeleton dynamics, among many cellular functions. The role of DOCK11 in human immune disease has been long suspected but, to the best of our knowledge, has never been described to date. We studied 8 male patients, from 7 unrelated families, with hemizygous DOCK11 missense variants leading to reduced DOCK11 expression. The patients were presenting with early-onset autoimmunity, including cytopenia, systemic lupus erythematosus, skin, and digestive manifestations. Patients' platelets exhibited abnormal ultrastructural morphology and spreading as well as impaired CDC42 activity. In vitro activated T cells and B-lymphoblastoid cell lines from patients exhibited aberrant protrusions and abnormal migration speed in confined channels concomitant with altered actin polymerization during migration. Knock down of DOCK11 recapitulated these abnormal cellular phenotypes in monocytes-derived dendritic cells and primary activated T cells from healthy controls. Lastly, in line with the patients' autoimmune manifestations, we also observed abnormal regulatory T-cell (Treg) phenotype with profoundly reduced FOXP3 and IKZF2 expression. Moreover, we found reduced T-cell proliferation and impaired STAT5B phosphorylation upon interleukin-2 stimulation of the patients' lymphocytes. In conclusion, DOCK11 deficiency is a new X-linked immune-related actinopathy leading to impaired CDC42 activity and STAT5 activation, and is associated with abnormal actin cytoskeleton remodeling as well as Treg phenotype, culminating in immune dysregulation and severe early-onset autoimmunity.

Comparison of incidence, causes and prognosis of adult and pediatric epidermal necrolysis: a population-based study in France.

BACKGROUND: Epidermal necrolysis (EN), comprising Stevens Johnson syndrome and toxic epidermal necrolysis is a rare and severe blistering reaction, mainly induced by drugs. Differences have been discussed between pediatric and adult patients regarding incidence, causes, and outcomes, but only based on a limited number of patients, in small case-series. OBJECTIVES: To directly compare incidence, causes and prognosis between adult and pediatric EN patients. METHODS: We used the French Health System Database from January 1st 2013 to December 31st 2022. We included adult and pediatric patients hospitalized for EN using the international classification of diseases, 10th revision codes combined with validated algorithms. The outcomes were incidence of EN; presence of a suspected drug before EN onset, defined by a new drug dispensation from 5 to 56 days before hospitalization; and in-hospital mortality. To estimate the association between pediatric EN and the presence of a suspected drug, we computed a multivariable logistic regression with odd ratios (OR). To estimate the association with mortality, we computed a multivariable Cox proportional hazard ratio (HR) model. RESULTS: A total of 1440 EN patients were included, with 799 (55.5%) females, comprising 219 children and 1221 adults. Among children, EN incidence was 1.5 cases (95%CI: 1.3-1.7) per million people year compared with 2.6 cases (95%CI: 2.5-2.7) in adults. Moreover, children had less chances to have a culprit drug before EN onset (93/219 (42.5%) versus 829/1221 (67.9%)), with an adjusted OR of 0.43 (95%CI: 0.32-0.59), p < 0.0001, together with a better prognosis, with death rates of 1.4% (95%CI: 0.4%-3.7%) in pediatric patients compared with 19.4% (95%CI: 17.3%-21.7%) in adult patients, and an adjusted HR of 0.12 (95%CI: 0.04-0.38), p = 0.0003 for in-hospital mortality. CONCLUSION: Pediatric EN seems to be rarer, with less chances to be caused by drugs, together with a better prognosis than adult EN. These results suggest the existence of different underlying pathophysiological mechanisms and clinical particularities between adult and pediatric patients.

Drugs associated with epidermal necrolysis in children: A World Health Organization pharmacovigilance database analysis.

BACKGROUND: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare life-threatening mucocutaneous reactions most often induced by drugs. To date, no large pharmacovigilance study has been conducted in the paediatric population. OBJECTIVES: To describe the spectrum of drugs associated with SJS-TEN in children through the analysis of cases reported in the WHO pharmacovigilance database (VigiBase). METHODS: Disproportionality study using data from VigiBase. All paediatric (age under 18 years) cases reported between January 1, 1967, and July 6, 2022, were included. For each molecule, a case-non-case study was performed to assess a potential pharmacovigilance signal by computing the lower end of the 95% credibility interval for the information component (IC025). We performed sensitivity analyses, (i) taking into account only cases reported by physicians and (ii) taking into account only cases reported in the last 10 years. RESULTS: Among 31,376,783 adverse drug reactions reported in VigiBase, 2,248,727 were paediatric cases and 7342 were encoded as paediatric SJS-TEN. Significant statistical pharmacovigilance signals were observed for 165 drugs. The two most represented drug classes were antiepileptics and anti-infectious drugs. The five drugs with the highest IC025 were lamotrigine (IC025 4.99), carbamazepine (IC025 4.88), phenobarbital (IC025 4.67), phenytoin (IC025 4.52) and nimesulide (IC025 4.23). Acetaminophen was significantly associated with paediatric SJS-TEN (IC025 2.85) and we also described various new suspected drugs. Vaccines had no significant pharmacovigilance signal. These results were confirmed with the sensitivity analyses. CONCLUSIONS: This study updates the spectrum of drugs potentially associated with paediatric SJS-TEN.

Ruxolitinib Rescues Multiorgan Clinical Autoimmunity in Patients with APS-1.

Autoimmune polyendocrine syndrome type-1 (APS-1) is caused by mono- or biallelic loss-of-function variants of the autoimmune regulator gene AIRE underlying early-onset multiorgan autoimmunity and the production of neutralizing autoantibodies against cytokines, accounting for mucosal candidiasis and viral diseases. Medical intervention is essential to prevent or attenuate autoimmune manifestations. Ruxolitinib is a JAK inhibitor approved for use in several autoimmune conditions. It is also used off-label to treat autoimmune manifestations of a growing range of inborn errors of immunity. We treated three APS-1 patients with ruxolitinib and followed them for at least 30 months. Tolerance was excellent, with no medical or biological adverse events. All three patients had remarkably positive responses to ruxolitinib for alopecia, nail dystrophy, keratitis, mucosal candidiasis, steroid-dependent autoimmune hepatitis, exocrine pancreatic insufficiency, renal potassium wasting, hypoparathyroidism, and diabetes insipidus. JAK inhibitors were therefore considered an effective treatment in three patients with APS-1. Our observations suggest that JAK/STAT pathways are involved in the pathogenesis of APS-1 autoimmune manifestations. They also suggest that JAK inhibitors should be tested in a broader range of APS-1 patients.

JAK Inhibition in Aicardi-Goutières Syndrome: a Monocentric Multidisciplinary Real-World Approach Study.

The paradigm type I interferonopathy Aicardi-Goutières syndrome (AGS) is most typically characterized by severe neurological involvement. AGS is considered an immune-mediated disease, poorly responsive to conventional immunosuppression. Premised on a chronic enhancement of type I interferon signaling, JAK1/2 inhibition has been trialed in AGS, with clear improvements in cutaneous and systemic disease manifestations. Contrastingly, treatment efficacy at the level of the neurological system has been less conclusive. Here, we report our real-word approach study of JAK1/2 inhibition in 11 patients with AGS, providing extensive assessments of clinical and radiological status; interferon signaling, including in cerebrospinal fluid (CSF); and drug concentrations in blood and CSF. Over a median follow-up of 17 months, we observed a clear benefit of JAK1/2 inhibition on certain systemic features of AGS, and reproduced results reported using the AGS neurologic severity scale. In contrast, there was no change in other scales assessing neurological status; using the caregiver scale, only patient comfort, but no other domain of everyday-life care, was improved. Serious bacterial infections occurred in 4 out of the 11 patients. Overall, our data lead us to conclude that other approaches to treatment are urgently required for the neurologic features of AGS. We suggest that earlier diagnosis and adequate central nervous system penetration likely remain the major factors determining the efficacy of therapy in preventing irreversible brain damage, implying the importance of early and rapid genetic testing and the consideration of intrathecal drug delivery.

Efficacy and safety of Oleogel-S10 (birch triterpenes) for epidermolysis bullosa: results from the phase III randomized double-blind phase of the EASE study.

BACKGROUND: Epidermolysis bullosa (EB) is a heterogeneous group of rare, difficult-to-treat, inherited multisystem diseases affecting epithelial integrity. Patients with EB are affected by mechanical fragility of epithelial surfaces including the skin and, as a result, extensive recurrent blistering is a characteristic of the condition. Chronic wounds predispose patients with EB to the development of squamous cell carcinoma, which is a major cause of premature death. OBJECTIVES: EASE was a double-blind, randomized, vehicle-controlled, phase III study to determine the efficacy and safety of the topical gel Oleogel-S10 (birch triterpenes) in EB. EASE was funded by Amryt Research Limited. METHODS: Patients with dystrophic EB, junctional EB or Kindler EB and a target partial-thickness wound lasting ≥ 21 days and < 9 months that was 10-50 cm2, were enrolled and randomized via computer-generated allocation tables 1 : 1 to Oleogel-S10 or control gel - both with standard-of-care dressings. Study gel was applied to all wounds at least every 4 days. The primary endpoint was the proportion of patients with first complete closure of target wound within 45 days. RESULTS: A total of 223 patients were enrolled and treated (109 treated with Oleogel-S10, 114 with control gel). The primary endpoint was met; Oleogel-S10 resulted in 41·3% of patients with first complete target wound closure within 45 days, compared with 28·9% in the control gel arm (relative risk 1·44, 95% confidence interval (CI) 1·01-2·05; P = 0·013). Adverse events (AEs) occurred with similar frequency for Oleogel-S10 (81·7%) compared with control gel (80·7%). AEs were predominantly of mild-to-moderate intensity (4·6% were severe). CONCLUSIONS: Oleogel-S10 is the first therapy to demonstrate accelerated wound healing in EB. Oleogel-S10 was well -tolerated.

Molecular and clinicopathologic characterization of pediatric histiocytoses.

The spectrum of somatic mutations in pediatric histiocytoses and their clinical implications are not fully characterized, especially for non-Langerhans cell histiocytosis (-LCH) subtypes. A cohort of 415 children with histiocytosis from the French histiocytosis registry was reviewed and analyzed for BRAFV600E . Most BRAFWT samples were analyzed by next-generation sequencing (NGS) with a custom panel of genes for histiocytosis and myeloid neoplasia. Of 415 case samples, there were 366 LCH, 1 Erdheim-Chester disease, 21 Rosai-Dorfman disease (RDD), 21 juvenile xanthogranuloma (JXG, mostly with severe presentation), and 6 malignant histiocytosis (MH). BRAFV600E was the most common mutation found in LCH (50.3%, n = 184). Among 105 non-BRAFV600E -mutated LCH case samples, NGS revealed mutations as follows: MAP2K1 (n = 44), BRAF exon 12 deletions (n = 26), and duplications (n = 8), other BRAF V600 codon mutation (n = 4), and non-MAP-kinase pathway genes (n = 5). Wild-type sequences were identified in 17.1% of samples. BRAFV600E was the only variant significantly correlated with critical presentations: organ-risk involvement and neurodegeneration. MAP-kinase pathway mutations were identified in seven RDD (mostly MAP2K1) and three JXG samples, but most samples were wild-type on NGS. Finally, two MH samples had KRAS mutations, and one had a novel BRAFG469R mutation. Rarely, we identified mutations unrelated to MAP-kinase pathway genes. In conclusion, we characterized the mutational spectrum of childhood LCH and clinical correlations of variants and subtypes. Variants responsible for JXG and RDD were not elucidated in more than half of the cases, calling for other sequencing approaches.

Clinical Features, Histological Characteristics, and Disease Outcomes of Mycosis Fungoides in Children and Adolescents: A Nationwide Multicentre Cohort of 46 Patients.

BACKGROUND: Our objective was to describe the clinical, histological characteristics, and disease outcome of a cohort of mycosis fungoides (MF) diagnosed during childhood including disease status at adulthood. METHODS: This is a retrospective multicentre survey of patients aged under 18 years at diagnosis with histologically confirmed MF. Patients' clinical and histological characteristics, treatments, and disease outcome (for patients followed for more than 12 months) were analysed. RESULTS: Forty-six patients were included (median age at diagnosis: 11 years; M:F sex ratio: 3:1) with 39 (85%) followed for at least 12 months. Thirty-nine patients (85%) had stage I MF. Hypopigmented patches were observed in 48% and folliculotropism in 43% patients. Immunophenotype of the skin infiltrate was predominantly CD8+ in 17% of patients. Initial management included a wait-and-see strategy in 6/39 (15%), skin-directed treatment in 27 (69%), and systemic treatment in 6 (15%) patients, respectively, with partial or complete clinical response (PR or CR) observed in 28 patients (72%). 14/39 patients (36%) relapsed after initial response. After a median follow-up period of 54 months, disease status at last news was PR or CR in 31/39 (79%), stable disease in 6 (15%), and progression in 2 (5%) patients. Histological transformation was observed in 3/39 (8%). Of the 15 patients followed until adulthood, 13 (87%) had persistent MF. DISCUSSION: This survey confirms the high frequency of hypopigmented and folliculotropic lesions and of CD8+ immunophenotype compared to adult MF patients. The long-term course is usually indolent but transformation may occur sometimes long after disease onset and the disease may persist during adulthood.

The Ectodermal Dysplasias-Burden of Disease Score: Development and Validation of an Ectodermal Dysplasia Family/Parental Burden Score.

Ectodermal dysplasias are genetic conditions affecting the development and/or homeostasis of 2 or more ectodermal derivatives, including hair, teeth, nails, and certain glands. No tool is available to assess the burden of ectodermal dysplasias and its multidimensional impact on patients and their families. This study developed and validated a familial/parental 19-item burden questionnaire designed specifically for ectodermal dysplasias. Each group of questions was linked to 1 of the following dimensions: (i) Impact of the disease on social life and hobbies; (ii) Future prospects; (iii) Restraint of the disease on outdoor activities; (iv) Financial burden of the disease; (v) Acceptance of the disease. Cronbach's alpha was 0.91 for the entire Ectodermal Dysplasias-Burden of Disease (ED-BD) scale, confirming excellent internal coherence. Intradimensional coherences all demonstrated excellent reliability (α > 0.76). The ED-BD questionnaire was highly correlated with the Short Form-12 and Psychological General Well Being Index validated questionnaires. Cultural and linguistic validation in US English was conducted. Development and validation of the questionnaire was based on data from patients with the 2 main ectodermal dysplasias subtypes. This ED-BD questionnaire represents the first specific assessment tool for evaluating the familial/parental burden of ectodermal dysplasias.

Accurate diagnosis of acute hemorrhagic edema of infancy: a French multicenter observational study.

The purpose of the study is to highlight clinical signs that are either suggestive of or against the diagnosis of AHEI to improve diagnosis and management. The medical records of children under 3 years old diagnosed with AHEI were retrospectively reviewed. Clinical data and photographs were reviewed by three independent experts, and the cases were classified as probable, doubtful, or unclear AHEI. Of the 69 cases of children diagnosed with AHEI included in 22 centers, 40 were classified as probable, 22 as doubtful, and 7 as unclear. The median age of patients with probable AHEI was 11 months [IQR 9-15], and they were in overall good condition (n = 33/40, 82.5%). The morphology of the purpura was targetoid in 75% of cases (n = 30/40) and ecchymotic in 70% of cases (n = 28/40) and affected mostly the legs (n = 39/40, 97%), the arms (n = 34/40, 85%), and the face (n = 33/40, 82.5%). Edema was observed in 95% of cases and affected mostly the hands (n = 36/38, 95%) and feet (n = 28/38, 74%). Pruritus was absent in all patients with probable AHEI and described for 6/21 with doubtful AHEI (29%). AHEI was the original diagnosis in only 24 patients (n = 24/40, 60%). The major differential diagnoses were purpura fulminans and urticaria multiforme.  Conclusion: AHEI, which the diagnosis is made on clinical findings, is often misdiagnosed. Purpuric lesions localized on the face/ears, arms/forearms, and thighs/legs with edema of the hands without pruritus in a young child with a good overall condition are highly suggestive of AHEI. What is Known: •Acute hemorrhagic edema of infancy (AHEI) is a cutaneous leukocytoclastic vasculitis affecting children under 3 years old. •Appropriate diagnosis is important to distinguish this benign disease from more serious diseases to avoid investigations and treatments, iatrogenic harm and unnecessary follow-up. What is New: •AHEI is an uncommon disorder often misdiagnosed by pediatricians and dermatologists. •Purpuric lesions localized on the face/ears, arms/forearms, and thighs/legs with edema of the hands without pruritus in an infant with a good overall condition are highly suggestive of AHEI.

Efficacy and tolerance of corticosteroids and methotrexate in patients with juvenile dermatomyositis: a retrospective cohort study.

OBJECTIVES: To assess the efficacy and tolerance of the conventional first-line treatment by MTX and CS in patients with JDM regardless of severity. METHODS: We conducted a monocentric retrospective study of patients with newly diagnosed JDM treated with MTX and CS from 2012 to 2020. The proportion of clinically inactive disease (CID) within 6 months of MTX initiation was evaluated using both Paediatric Rheumatology International Trials Organisation (PRINTO) criteria (evaluating muscle inactive disease) and DAS (evaluating skin inactive disease). We compared responders and non-responders using univariate analyses. RESULTS: Forty-five patients with JDM, out of which 30 (67%) severe JDM, were included. After 6 months of treatment with MTX and CS, complete CID, muscle CID and skin CID were achieved in 14/45 (31%), 19/45 (42%) and 15/45 (33%) patients, respectively. The absence of myositis-specific (MSA) or myositis-associated autoantibodies (MAA) at diagnosis was associated with a better overall, cutaneous and muscular therapeutic response, compared with antibody-positive forms (P < 0.01). Requirement for ICU (P = 0.029) and cutaneous ulcerations (P = 0.018) were associated with a less favourable muscle response. MTX was stopped due to intolerance in six patients (13%) before month 6. CONCLUSIONS: Conventional first-line treatment with MTX was not efficient in a large subset of JDM patients, especially in patients with MSA-positive forms, and in patients with severe JDM. Larger, multicentre cohorts are required to confirm these data and to identify new predictive biomarkers of MTX response, in order to treat patients with JDM as early as possible with appropriate targeted drugs.

Eosinophilic Pustular Folliculitis of Infancy: A Histologic Assessment of 43 Cases.

ABSTRACT: Eosinophilic pustular folliculitis of infancy is a sterile, inflammatory dermatosis that mainly affects children younger than 36 months. The underlying physiopathologic mechanism is unclear. Clinical diagnosis is challenging, and a skin biopsy may be necessary. The literature data are sometimes contradictory, and a histologic series of eosinophilic pustular folliculitis of infancy cases has not been previously published.

Stability and Formulation of Erlotinib in Skin Creams.

Recent studies have highlighted the benefit of repurposing oral erlotinib (ERL) treatment in some rare skin diseases such as Olmsted syndrome. The use of a topical ERL skin treatment instead of the currently available ERL tablets may be appealing to treat skin disorders while reducing adverse systemic effects and exposure. A method to prepare 0.2% ERL cream, without resorting to a pure active pharmaceutical ingredient, was developed and the formulation was optimized to improve ERL stability over time. Erlotinib extraction from tablets was incomplete with Transcutol, whereas dimethyl sulfoxide (DMSO) allowed 100% erlotinib recovery. During preliminary studies, ERL was shown to be sensitive to oxidation and acidic pH in solution and when added to selected creams (i.e., Excipial, Nourivan Antiox, Pentravan, and Versatile). The results also showed that use of DMSO (5% v/w), neutral pH, as well as a topical agent containing antioxidant substances (Nourivan Antiox) were key factors to maintain the initial erlotinib concentration. The proposed ERL cream formulation at neutral pH contains a homogeneous amount of ERL and is stable for at least 42 days at room temperature in Nourivan cream with antioxidant properties.

Differential Expression of Interferon-Alpha Protein Provides Clues to Tissue Specificity Across Type I Interferonopathies.

Whilst upregulation of type I interferon (IFN) signaling is common across the type I interferonopathies (T1Is), central nervous system (CNS) involvement varies between these disorders, the basis of which remains unclear. We collected cerebrospinal fluid (CSF) and serum from patients with Aicardi-Goutières syndrome (AGS), STING-associated vasculopathy with onset in infancy (SAVI), presumed monogenic T1Is (pT1I), childhood systemic lupus erythematosus with neuropsychiatric features (nSLE), non-IFN-related autoinflammation (AI) and non-inflammatory hydrocephalus (as controls). We measured IFN-alpha protein using digital ELISA. Eighty-two and 63 measurements were recorded respectively in CSF and serum of 42 patients and 6 controls. In an intergroup comparison (taking one sample per individual), median CSF IFN-alpha levels were elevated in AGS, SAVI, pT1I, and nSLE compared to AI and controls, with levels highest in AGS compared to all other groups. In AGS, CSF IFN-alpha concentrations were higher than in paired serum samples. In contrast, serum IFN was consistently higher compared to CSF levels in SAVI, pT1I, and nSLE. Whilst IFN-alpha is present in the CSF and serum of all IFN-related diseases studied here, our data suggest the primary sites of IFN production in the monogenic T1I AGS and SAVI are, respectively, the CNS and the periphery. These results inform the diagnosis of, and future therapeutic approaches to, monogenic and multifactorial T1Is.

JAK inhibitors are effective in a subset of patients with juvenile dermatomyositis: a monocentric retrospective study.

OBJECTIVE: To evaluate the efficacy and safety of Janus kinase inhibitors (JAKis) in JDM. METHODS: We conducted a single-centre retrospective study of patients with JDM treated by JAKi with a follow-up of at least 6 months. Proportion of clinically inactive disease (CID) within 6 months of JAKi initiation was evaluated using PRINTO criteria and skin Disease Activity Score. Serum IFN-α concentration was measured by Simoa assay. RESULTS: Nine refractory and one new-onset patients with JDM treated with ruxolitinib (n = 7) or baricitinib (n = 3) were included. The main indications for treatment were refractory muscle involvement (n = 8) and ulcerative skin disease (n = 2). CID was achieved in 5/10 patients (two/two anti-MDA5, three/four anti-NXP2, zero/three anti-TIF1γ-positive patients) within 6 months of JAKi introduction. All responders could withdraw plasmatic exchange, immunoadsorption and other immunosuppressive drugs. The mean daily steroid dose decreased from 1.1 mg/kg (range 0.35-2 mg/kg/d) to 0.1 (range, 0-0.3, P = 0.008) in patients achieving CID, and was stopped in two. Serum IFN-α concentrations were elevated in all patients at the time of treatment initiation and normalized in both responder and non-responder. A muscle biopsy repeated in one patient 26 months after the initiation of JAKi, showed a complete restoration of muscle endomysial microvascular bed. Herpes zoster and skin abscesses developed in three and two patients, respectively. CONCLUSION: JAKis resulted in a CID in a subset of new-onset or refractory patients with JDM and may dramatically reverse severe muscle vasculopathy. Overall tolerance was good except for a high rate of herpes zoster infection.

The Burden of Autosomal Recessive Congenital Ichthyoses on Patients and their Families: An Italian Multicentre Study.

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.

Therapeutic plasma exchange for life-threatening pediatric disorders.

INTRODUCTION: Therapeutic plasma exchange (TPE) is acknowledged to be an effective treatment in life-threatening pediatric disorders. Apheresis for pediatric diseases has been poorly investigated, and most studies to date featured small numbers of patients and lacked control groups. The objective of the present study was to evaluate the tolerance of TPE in pediatric patients. MATERIALS AND METHODS: A retrospective cohort study via a web-based electronic case report form including pediatric patients referred for TPE between January 2005 and December 2014. RESULTS: A total of 78 patients (median [range] age: 9.8 [0.53-17.93]) and 731 TPE procedures were analyzed. The indications were antibody-mediated rejection (n = 33; 42%) and desensitization therapy (n = 5; 6%) after solid organ or hematopoietic stem cell transplantation, thrombotic microangiopathy (n = 17; 22%), pediatric inflammatory diseases (n = 16; 21%), kidney diseases (n = 6; 8%), and hyperviscosity syndrome (n = 1; 1%). On average, each patient underwent six procedures during the first session [range: 1-19]. In the 2 weeks following the start of a session, 72 patients (92%) presented a total of 311 adverse events (AEs) potentially related to TPE. The risk of AEs was not related to the indication for TPE, the intensity of care, venous access, plasma substitute use, or body weight. None of the deaths was related to the TPE. CONCLUSION: We studied one of the largest retrospective pediatric cohorts described to date. Our experience of TPE children's TPE feasibility concerned specific, life-threatening conditions and otherwise treatment-refractory diseases.

Devastating Gynecological Infections in Women with STAT3 Deficiency.

We provide the first description of a series of 9 severe gynecological infections (mastitis and pelvic cellulitis) occurring in the French national cohort of women with STAT3 deficiency. Each episode had unique features in terms of clinical presentation, microbial documentation, location, treatment duration, and related persistent esthetic damage.

Anti-MDA5 juvenile idiopathic inflammatory myopathy: a specific subgroup defined by differentially enhanced interferon-α signalling.

OBJECTIVES: JDM and juvenile overlap myositis represent heterogeneous subtypes of juvenile idiopathic inflammatory myopathy (JIIM). Chronic evolution can occur in up to 60% of cases, and morbidity/mortality is substantial. We aimed to describe the clinical, biological, histological and type I IFN status in JIIM associated with anti-melanoma differentiation-associated protein 5 (anti-MDA5) autoantibodies at presentation (group 1) in comparison with other JIIM (group 2). METHODS: This was a retrospective and prospective study of patients with JIIM ascertained from three French paediatric rheumatology reference centres between 2013 and 2019. Muscle biopsies were reviewed. Type I interferon pathway activity was assessed by dosage of IFNα serum protein and the expression of IFN-stimulated genes. RESULTS: Sixty-four patients were included, 13 in group 1 (54% JDM and 46% juvenile overlap myositis) and 51 in group 2 (76% JDM and 24% juvenile overlap myositis). Group 1 patients demonstrated more arthritis, skin ulcerations, lupus features and interstitial lung disease, and a milder muscular involvement. Serum IFNα levels were higher in group 1 than 2, and decreased after treatment or improvement in both groups. Outcome was similar in both groups. Unconventional treatment (more than two lines) was required in order to achieve remission, especially when skin ulceration was reported. CONCLUSION: This study indicates a higher frequency of arthritis, skin ulcerations and interstitial lung disease, but milder muscular involvement, in JIIM with positive anti-MDA5 autoantibodies compared with other JIIM. Our data support an important role of systemic IFNα in disease pathology, particularly in the anti-MDA5 auto-antibody-positive subgroup. In severe and refractory forms of JIIM, IFNα may represent a therapeutic target.

The histopathology of congenital haemangioma and its clinical correlations: a long-term follow-up study of 55 cases.

AIMS: Congenital haemangiomas (CHs) can be subdivided into different subtypes [rapidly involuting CHs (RICHs), non-involuting CHs (NICHs), and partially involuting CHs (PICHs)]. During the first few days of life, RICHs may be associated with transient but sometimes marked thrombocytopenia. We sought to assess the histological aspects and clinicopathological correlations of the three subtypes. METHODS AND RESULTS: We assessed the histopathological features of 10 RICHs, 25 NICHs, and 20 PICHs, described the patients' long-term clinical outcomes, and assessed clinicopathological correlations. All CHs were located in the dermis and hypodermis, and comprised both capillary lobules (with three distinct histopathological patterns) and extralobular large vessels. Most of the extralobular vessels were abnormal veins and abnormal lymphatic vessels. We did not observe significant correlations between the CH subtype, the histopathological pattern, and the time of the histopathological assessment. Interestingly, unexpected intralobular expression of podoplanin was found in neonatal biopsies of five RICHs and PICHs. Four of these five patients had concomitant thrombocytopenia. The podoplanin staining intensity decreased over time as the thrombocytopenia resolved and the tumour shrank. CONCLUSION: The histopathological features were similar in all three subtypes of CH, and were related to the time since disease onset; we consider that RICH, PICH and NICH form a single entity and differ only in their involuting potential. Along with the transient expression of intralobular podoplanin observed in some specimens from the newborn, the lobular architecture might lead to misdiagnosis of tufted haemangioma or kaposiform haemangioendothelioma.