Neutrophilic dermatoses in children

Inflammasomes in epithelial innate immunity: front line warriors

Our epithelium represents a battle ground against a variety of insults including pathogens and danger signals. It encodes multiple sensors that detect and respond to such insults, playing an essential role in maintaining and defending tissue homeostasis. One key set of defense mechanisms is our inflammasomes which drive innate immune responses including, sensing and responding to pathogen attack, through the secretion of pro-inflammatory cytokines and cell death. Identification of physiologically relevant triggers for inflammasomes has greatly influenced our ability to decipher the mechanisms behind inflammasome activation. Furthermore, identification of patient mutations within inflammasome components implicates their involvement in a range of epithelial diseases. This review will focus on exploring the roles of inflammasomes in epithelial immunity and cover: the diversity and differential expression of inflammasome sensors amongst our epithelial barriers, their ability to sense local infection and damage and the contribution of the inflammasomes to epithelial homeostasis and disease.

Congenital erosive and vesicular dermatosis healing with reticulated and supple scarring: Two cases secondary to fungal infection

Congenital erosive and vesicular dermatosis (CEVD) is a rare skin condition that most commonly presents as erosive and vesicular lesions on the trunk and extremities in premature infants and heals with characteristic reticulated and supple scarring (RSS). The exact pathogenesis of CEVD is unknown and is typically a diagnosis of exclusion. We present the cases of two extremely premature neonates with Candida septicemia who were found to have diffuse, erythematous skin eruptions shortly after birth that ultimately healed with RSS. Through these cases, we highlight the importance of including fungal infection in the work-up of CEVD healing with RSS.

Comparison of Safety and Biological Efficacy of Anakinra (Kineret) Dispensed in Polycarbonate Plastic versus Borosilicate Glass Syringes: A Patient-Level Analysis of VCUART2 and VCUART3 Clinical Trials

Anakinra is a recombinant human interleukin-1 receptor antagonist approved for the treatment of inflammatory diseases. Kineret is available as a solution prepared in a borosilicate glass syringe. For implementing a placebo-controlled double-blind randomized clinical trial, anakinra is commonly transferred into plastic syringes. However, there is limited data on anakinra's stability in polycarbonate syringes. We described the results of our previous studies on the use of anakinra in glass (VCUART3) versus plastic syringes (VCUART2) compared with placebo. These studies were conducted in patients with ST-segment elevation myocardial infarction (STEMI), and we assessed the anti-inflammatory effects of anakinra versus placebo by comparing the area under the curve for high-sensitivity cardiac reactive protein (AUC-CRP) levels during the first 14 days of STEMI, its clinical effects on heart failure (HF) hospitalization, cardiovascular death, or new diagnosis of HF as well as adverse events profile between groups. The levels of AUC-CRP were 75 (50-255 mg·day/l) for anakinra in plastic syringes versus 255 (116-592 mg·day/l) in placebo and 60 (24-139 mg·day/l) and 86 (43-123 mg·day/l) for anakinra once and twice daily in glass syringes, respectively, compared with placebo 214 (131-394 mg·day/l). The rate of adverse events was also comparable between groups. There were no differences in the rate of HF hospitalization or cardiovascular death in patients who received anakinra in plastic or glass syringes. Fewer cases of new-onset heart failure occurred in patients receiving anakinra in plastic or glass syringes compared with placebo. Anakinra stored in plastic (polycarbonate) syringes provides comparable biologic and clinical effect to glass (borosilicate) syringes. SIGNIFICANCE STATEMENT: Anakinra (Kineret) 100 mg administered subcutaneously in patients with ST-segment elevation myocardial infarction (STEMI) for a duration of up to 14 days appears to have comparable safety and biological efficacy signals when delivered in prefilled glass or transferred into plastic polycarbonate syringes. This may have important implications for the feasibility of designing clinical trials in STEMI and other clinical conditions.

Interleukin 1α: a comprehensive review on the role of IL-1α in the pathogenesis and treatment of autoimmune and inflammatory diseases

The interleukin (IL)-1 family member IL-1α is a ubiquitous and pivotal pro-inflammatory cytokine. The IL-1α precursor is constitutively present in nearly all cell types in health, but is released upon necrotic cell death as a bioactive mediator. IL-1α is also expressed by infiltrating myeloid cells within injured tissues. The cytokine binds the IL-1 receptor 1 (IL-1R1), as does IL-1β, and induces the same pro-inflammatory effects. Being a bioactive precursor released upon tissue damage and necrotic cell death, IL-1α is central to the pathogenesis of numerous conditions characterized by organ or tissue inflammation. These include conditions affecting the lung and respiratory tract, dermatoses and inflammatory skin disorders, systemic sclerosis, myocarditis, pericarditis, myocardial infarction, coronary artery disease, inflammatory thrombosis, as well as complex multifactorial conditions such as COVID-19, vasculitis and Kawasaki disease, Behcet's syndrome, Sjogren Syndrome, and cancer. This review illustrates the clinical relevance of IL-1α to the pathogenesis of inflammatory diseases, as well as the rationale for the targeted inhibition of this cytokine for treatment of these conditions. Three biologics are available to reduce the activities of IL-1α; the monoclonal antibody bermekimab, the IL-1 soluble receptor rilonacept, and the IL-1 receptor antagonist anakinra. These advances in mechanistic understanding and therapeutic management make it incumbent on physicians to be aware of IL-1α and of the opportunity for therapeutic inhibition of this cytokine in a broad spectrum of diseases.

Recurrent Aphthous Stomatitis in Children: A Practical Guideline for Paediatric Practitioners

Recurrent aphthous stomatitis (RAS) is the most common chronic oral mucosal lesion affecting up to 25% of the population. The diagnosis is based on well-defined clinical characteristics, but the precise aetiology and pathogenesis remain unclear. The treatment of RAS should be based on the identification and control of possible predisposing factors. A wide range of topical medicaments is available as antiseptics, anti-inflammatory drugs and corticosteroids. The systemic treatment is indicated in patients with continuous and aggressive manifestation, which is extremely rare in children. The present article provides a review of the current concept and knowledge of the aetiology, pathogenesis, and management of RAS in the paediatric population.

Neutrophilic eccrine hidradenitis secondary to pegfilgrastim in a patient with synovial sarcoma

Here, we report a case of neutrophilic eccrine hidradenitis (NEH) in a teenage male with synovial sarcoma associated with extracutaneous manifestations including myositis and splenomegaly secondary to pegfilgrastim. To the best of our knowledge, NEH has not been previously reported to occur in association with extracutaneous manifestations.

Neutrophilic superficial eccrine ductitis: Proposal of a new disease concept

A 3-year-old Japanese boy presented with a 3-month history of itchy erythematous papules on his trunk and forearms, the histologic findings of which were characterized by predominantly neutrophilic inflammation within and around the eccrine sweat ducts and obliteration and disruption of the superficial eccrine sweat ducts. Although the skin disorder had some clinical and histopathologic similarity to miliaria and neutrophilic eccrine hidradenitis, it was ultimately conformed to be neither disorder. Based on this and a case report in the Japanese literature of a 1-year-old boy with erythematous eruptions whose clinical and histopathologic findings were similar to those in our case, we propose the skin disorder in our case, referred to as "neutrophilic superficial eccrine ductitis," as a unique entity.

Function and regulation of IL-1α in inflammatory diseases and cancer

The interleukin (IL)-1 family of cytokines is currently comprised of 11 members that have pleiotropic functions in inflammation and cancer. IL-1α and IL-1β were the first members of the IL-1 family to be described, and both signal via the same receptor, IL-1R. Over the last decade, much progress has been made in our understanding of biogenesis of IL-1β and its functions in human diseases. Studies from our laboratory and others have highlighted the critical role of nod-like receptors (NLRs) and multi-protein complexes known as inflammasomes in the regulation of IL-1β maturation. Recent studies have increased our appreciation of the role played by IL-1α in inflammatory diseases and cancer. However, the mechanisms that regulate the production of IL-1α and its bioavailability are relatively understudied. In this review, we summarize the distinctive roles played by IL-1α in inflammatory diseases and cancer. We also discuss our current knowledge about the mechanisms that control IL-1α biogenesis and activity, and the major unanswered questions in its biology.

Postoperative Pyoderma Gangrenosum in Children: The Case Report of a 13-Year-Old Boy With Pyoderma Gangrenosum After Hip Reconstruction Surgery and a Review of the Literature

BACKGROUND

Postoperative pyoderma gangrenosum (PG) is a neutrophilic dermatosis and pathergic reaction at surgical sites. Reports of children with postoperative PG are rare in the literature.

METHODS

We report the case of a 13-year-old boy without any known preexisting illnesses, who developed severe systemic response and wound deterioration after elective hip reconstruction surgery. The working diagnosis of necrotizing fasciitis was later determined to be postoperative PG.

RESULTS

The patient was successfully treated by the systemic application of corticosteroids.

CONCLUSIONS

Postoperative PG is a very rare complication after surgery, especially in children. If mistaken for necrotizing fasciitis, it can substantially mutilate a patient because PG is worsened by surgical debridement. It can be treated successfully only by corticosteroids and other immunosuppressive drugs.

LEVEL OF EVIDENCE

Level IV-this is a case report.

Pediatric pyoderma gangrenosum: a systematic review and update

Pyoderma gangrenosum (PG) is a sterile neutrophilic disorder that rarely affects children. Clinical, epidemiological, and therapeutic data on pediatric PG is poor as there are many newly reported associated diseases and drugs. This paper aims to review all recent available data on pediatric PG. A systematic review of the literature was conducted using Embase, Medline, and Cochrane databases. A total of 132 articles were included in the review. The most commonly reported underlying diseases in pediatric PG are inflammatory bowel diseases followed by hematologic disorders, vasculitis, immune deficiencies and Pyogenic Arthritis, Pyoderma gangrenosum and Acne (PAPA) syndrome. More than half of the cases occur with no underlying disease. The most frequently reported clinical presentation is multiple disseminated ulcers. Treatment should be tailored according to the underlying etiology. It includes systemic steroids, corticosteroid sparing agents such as dapsone and cyclosporine, and TNF-alpha inhibitors such as adalimumab and infliximab. Response to treatment is high with cure rates reaching 90%. A high index of suspicion and a thorough workup are mandatory in the management of pediatric PG.

A Review and Proposed Approach to the Neutrophilic Dermatoses of Childhood

Neutrophilic dermatoses (NDs) are inflammatory skin conditions that are not associated with infection. The classification and clinical approach to these conditions in children is poorly described. This review classifies these conditions into five nosological subtypes: Sweet's syndrome, pyoderma gangrenosum, aseptic pustules, neutrophilic urticarial dermatoses, and Marshall's syndrome. In addition, we review the various secondary diseases that need to be excluded in the clinical management of the NDs of childhood, with a focus on the autoinflammatory conditions that the reader may not be familiar with. We propose a practical clinical approach to these disorders.

Neutrophilic dermatoses: an update

Neutrophilic dermatoses constitute a heterogeneous group of dermatologic diseases, which are unified by the predominance of neutrophils within the inflammatory infiltrate on histopathology. The aims of this review were to provide an update on the clinical and histologic presentation of the main neutrophilic dermatoses and to develop a guide for clinical practice. A structured literature search of PubMed, Medline, and Embase was performed, using the key words "neutrophilic disorders", "cutaneous small vessel vasculitis", "Sweet's syndrome", "bowel associated dermatosis arthritis syndrome", "Behcet's", "palisaded neutrophilic and granulomatous dermatosis", "rheumatoid neutrophilic dermatitis", and "pyoderma gangrenosum". Related articles were screened for key terms and were included if appropriate. This group contains a wide spectrum of unique disorders, each with its own histologic and clinical subtleties, making specific diagnosis of a given entity within the group diagnostically challenging. The fact that overlapping forms of neutrophilic dermatoses, which share features of multiple neutrophilic dermatoses, are not uncommon makes the diagnoses more challenging.

SHP-1 and IL-1α conspire to provoke neutrophilic dermatoses

Neutrophilic dermatoses are a spectrum of autoinflammatory skin disorders that are characterized by extensive infiltration of neutrophils into the epidermis and dermis. The underlining biological pathways that are responsible for this heterogeneous group of cutaneous diseases have remained elusive. However, recent work from our laboratory and other groups has shown that missense mutations in Ptpn6, which encodes for the non-receptor protein tyrosine phosphatase Src homology region 2 (SH2) domain-containing phosphatase-1 (SHP-1), results in a skin disease with many of the major histopathological and clinical features that encompass neutrophilic dermatoses in humans. In particular, we found that loss-of-function mutation in Ptpn6 results in unremitting footpad swelling, suppurative inflammation, and neutrophilia. Dysregulated wound healing responses were discovered to contribute to chronic inflammatory skin disease in SHP-1 defective mice and genetic abrogation of interleukin-1 receptor (IL-1R) protected mice from cutaneous inflammation, suggesting that IL-1-mediated events potentiate disease. Surprisingly, inflammasome activation and IL-1β-mediated events were dispensable for Ptpn6^spin-mediated footpad disease. Instead, RIP1-mediated regulation of IL-1α was identified to be the major driver of inflammation and tissue damage.

The adverse consequences of pyoderma gangrenosum in a 13 year old child

INTRODUCTION

Pyoderma gangrenosum (PG) is an uncommon, but serious, non infectious, neutrophilic dermatosis that causes cutaneous necrosis with a characteristically rapid evolution.

PRESENTATION OF CASE

A 13 year-old girl was admitted with a postoperative infected wound, which was surgically debrided. A new more aggressive lesion on the left upper extremity led the patient to the intensive care unit. Clinical diagnosis of pyoderma gangrenosum was introduced with a crucial delay. An immediate clinical improvement after immunosuppressive therapy with systemic corticosteroids and cyclosporine was observed. The extensive cutaneous deficits were covered with keratinocyte cultured cells with an aesthetically good outcome.

DISCUSSION

Diagnosis of PG in young children is very difficult, especially without dermatological evaluation. This deforming ulcerative skin disease is probably a result of altered immunologic reactivity. Its early recognition may prevent unnecessary surgical treatment which leads to dangerous complications.

CONCLUSION

To our knowledge this is the first case of PG with such a widespread distribution reported in a child, as a consequence of iatrogenic pathergy.

Dermatoses neutrofílicas: parte II

Neste artigo são abordadas as dermatoses neutrofílicas, complementando o artigo anterior (parte I). São apresentadas e comentadas as seguintes dermatoses: pustulose subcórnea de Sneddon-Wilkinson, dermatite crural pustulosa e atrófica, pustulose exantemática generalizada aguda, acroder matite contínua de Hallopeau, pustulose palmoplantar, acropustulose infantil, bacteride pustular de Andrews e foliculite pustulosa eosinofílica. Uma breve revisão das dermatoses neutrofílicas em pacientes pediátricos também é realizada.

Epidermolysis bullosa nevus-like lesions in a pediatric patient with pyoderma gangrenosum

Epidermolysis bullosa-associated nevi are recently described dysplastic nevi found in patients with epidermolysis bullosa. These lesions display clinical features of unusual nevi suggestive of malignancy but thus far cases with malignant transformation have not been reported. We describe a case of epidermolysis bullosa-type nevi developing in a child with pyoderma gangrenosum. The nevi in our patient were found in areas previously affected by pyoderma gangrenosum and were clinically concerning for malignancy. However, they were only moderately atypical on light and confocal microscopy. This case demonstrates that pediatric patients with cutaneous inflammation, bullae formation, or both, are at risk for developing unusual nevi at previous sites of skin involvement. Considering the absence of malignant change in these nevi, we suggest that close observation can be employed in cases where this diagnosis can be confirmed both clinically and microscopically.