ABSTRACT
A 39-year-old Caucasian woman affected by Noonan Syndrome (NS) mutated in RAF1 was referred to us with itchy lesions on her limbs that had appeared two months earlier. Clinically, there were multiple umbilicated papules with a hyperkeratotic central plug, localized on the upper and lower limbs (Figure 1, a-b). The patient had no personal history of diabetes mellitus and no chronic renal failure, but suffered from hypertrophic cardiomyopathy. Blood tests showed no abnormalities. On histological examination of a skin lesion, an ectatic hair follicle with hyperkeratotic ostium was observed with fragments of hair, inflammatory cells, and epidermal perforation. A final diagnosis of Kyrle's disease (KD) was established. The patient underwent narrowband UVB (NB-UVB) phototherapy with residual atrophic scars (Figure 1, c-d) but with complete and long-lasting resolution of symptoms as well. KD belongs to perforating dermatoses (PD), a heterogeneous group of skin diseases characterized by the transepidermal elimination of dermal components. Despite the classification of PD being debated, four primary forms are traditionally recognized: reactive perforating collagenosis, elastosis perforans serpiginosum, perforating folliculitis, and KD (1). The typical skin manifestation of KD is an eruption of dome-shaped papules and nodules with a whitish central keratotic plug, mainly localized on the extremities and the buttocks. Described by Kyrle in 1916, KD is frequently associated with systemic diseases, especially chronic renal failure and diabetes mellitus. Other associated conditions include chronic hepatic disease, internal malignancies, and congestive heart disease (1). Despite the absence of a consensus, the control of the underlying disease remains the first therapeutic target. Both topical (keratolytics, retinoids, and corticosteroids) and systemic treatments (corticosteroid, retinoids, antibiotics, and phototherapy) have been reported to control skin manifestations (2). In our experience, NB-UVB is an effective option as first-line therapy in case of diffuse lesions, both in KD and in other PDs (3). NS is a relatively common RASopathy, an heterogenous group of genetic disease characterized by a defect of the Ras-mitogen-activated protein kinase (Ras-MAPK) pathway, with an estimated prevalence of 1/1000-2500. PTPN11 is the most frequent mutated gene, accounting for 50% of cases, but more than ten genes were identified as causing NS (4). Classical features include a distinctive facial dysmorphism, short stature, pulmonic stenosis, and other anomalies of different organs. The skin is commonly involved. Keratinization disorders and hair abnormalities such as keratosis pilaris, ulerythema ophryogenes, wavy or curly hair, and scarce scalp hair are often described. Other cutaneous signs include easy bruising, skin hyperlaxity, multiple lentigines, and café-au-lait spots (5). To the best of our knowledge, no cases of KD in patients with NS have been previously reported to date. The exact etiopathogenesis of KD is not clear, but it was hypothesized that systemic diseases, such as diabetes and chronic renal failure, can cause a deposit of substances or dermis alterations, which triggers the inflammatory process with subsequent transepidermal extrusion (1). In our patient, we ruled out all the causes commonly associated with KD. It is however possible that this manifestation could be a direct result of our patient's illness. Our patient suffered from diffuse keratosis pilaris, and one of the possible pathogenetic mechanisms of KD was theorized to be an abnormal epidermal keratinization with a secondary inflammatory dermic response (1). On the other hand, the hyperlaxity and fragility of the skin typical of NS suggest the presence of altered connective tissue, which could trigger an abnormal keratinization and, subsequently, the transepidermal extrusion, as well as perforating elastosis, and is associated with genetic connective tissue diseases (1). Moreover, our patient suffered from a cardiac disease, another condition associated with KD (5). Although these explanations have their appeal, there is currently insufficient evidence of a link between KD and NS, and it will be necessary to collect additional data to confirm this hypothesis.
Subject(s)
Noonan Syndrome , Humans , Female , Noonan Syndrome/complications , Noonan Syndrome/therapy , Adult , Ultraviolet Therapy , Darier DiseaseABSTRACT
Human crowds display various self-organized collective behaviours, such as the spontaneous formation of unidirectional lanes in bidirectional pedestrian flows. In addition, parts of pedestrians' footsteps are known to be spontaneously synchronized in one-dimensional, single-file crowds. However, footstep synchronization in crowds with more freedom of movement remains unclear. We conducted experiments on bidirectional pedestrian flows (24 pedestrians in each group) and examined the relationship between collective footsteps and self-organized lane formation. Unlike in previous studies, pedestrians did not spontaneously synchronize their footsteps unless following external auditory cues. Moreover, footstep synchronization generated by external cues disturbed the flexibility of pedestrians' lateral movements and increased the structural instability of spatial organization. These results imply that, without external cues, pedestrians marching out of step with each other can efficiently self-organize into robust structures. Understanding how asynchronous individuals contribute to ordered collective behaviour might bring innovative perspectives to research fields concerned with self-organizing systems.
Subject(s)
Pedestrians , Humans , Male , Female , Crowding , Adult , Walking/physiologyABSTRACT
Pemphigus is a chronic autoimmune bullous disease associated with the production of autoantibodies directed against desmosomal proteins, such as desmogleins 1 and 3. Here, we present the case of an 83-year-old woman who was referred to us with suspicious cicatricial alopecia of the scalp and a small, eroded lesion on the forehead, previously labeled as atrophic actinic keratosis after a skin biopsy. In our clinic, after a careful examination of the case, we decided to perform two new skin biopsies of the scalp on suspicion of an inflammatory disease.
ABSTRACT
Autoimmune bullous diseases are a heterogeneous group of rare conditions clinically characterized by the presence of blisters and/or erosions on the skin and the mucous membranes. Practically, they can be divided into two large groups: the pemphigoid group and the pemphigus group, depending on the depth of the autoimmune process on the skin. A family history of autoimmune diseases can often be found, demonstrating that genetic predisposition is crucial for their development. Moreover, numerous environmental risk factors, such as solar radiation, drugs, and infections, are known. This study aimed to evaluate how seasonality can affect the trend of bullous pemphigoid and pemphigus vulgaris, especially considering the number of hospitalizations recorded over the course of individual months. The total number of hospitalizations in the twelve months of the year was evaluated. Moreover, blood chemistry assay and, for some patients, enzyme-linked immunosorbent assay were executed to evaluate antibodies. Regarding the severity of the disease, the bullous pemphigoid area index and the pemphigus disease area index score systems were used. Results showed a complex interplay between environmental factors such as seasons and autoimmune conditions.
Subject(s)
Melanosis , Skin Neoplasms , Humans , Skin Neoplasms/diagnosis , Skin Neoplasms/pathology , Melanosis/diagnosis , Melanosis/pathologyABSTRACT
We report the case of a patient with chronic granulomatous disease and acne treated with isotretinoin, who developed a diffuse staphylococcal skin infection during the therapy. Chronic granulomatous disease is a rare genetic disorder characterized by an altered innate immunity with an increased risk of potentially lethal bacterial and fungal infections. Although chronic granulomatous disease is rare, acne is a common manifestation in these patients, but there are no data about the gold standard therapy.
ABSTRACT
Pemphigus vulgaris (PV) is a rare, potentially lethal blistering disease typically occurring in adulthood and characterized by autoantibodies directed against mucocutaneous desmosomal proteins. Clinically, flaccid vesicles, bullae and erosions after breakage are the main clinical features. According to the literature, the incidence of PV is rare in the pediatric population, ranging from 1 to 4% of reported cases. We describe an interesting case of a 12-year-old boy with severe PV that was referred to our university hospital for a mucocutaneous disease resistant to anti-infective therapy. Following the appearance of bullous lesions on the skin, antibody screening for autoimmune diseases showed positivity for PV and corticosteroid therapy was started. In view of the numerous adverse effects, we decided to set up biological therapy with rituximab, which was interrupted due to the onset of an urticarial reaction. Further second-line therapies were therefore attempted, with only a partial response. For this reason, a desensitizing therapy with rituximab was decided, thus allowing a clear improvement in the clinical picture and quality of life of the patient. To the best of our knowledge, this is the first report of a child with severe PV resistant to conventional therapies and with an urticarial reaction to rituximab. This case highlights that despite PV being extremely rare in the pediatric population, this diagnosis should not be entirely discounted. In case of severe clinical manifestations, rituximab represents a valid option in children and desensitization tests should be recommended in the presence of hypersensitivity to this drug.
ABSTRACT
Pedestrian groups are commonly found in crowds but research on their social aspects is comparatively lacking. To fill that void in literature, we study the dynamics of collision avoidance between pedestrian groups (in particular dyads) and individual pedestrians in an ecological environment, focusing in particular on (i) how such avoidance depends on the group's social relation (e.g. colleagues, couples, friends or families) and (ii) its intensity of social interaction (indicated by conversation, gaze exchange, gestures etc). By analyzing relative collision avoidance in the "center of mass" frame, we were able to quantify how much groups and individuals avoid each other with respect to the aforementioned properties of the group. A mathematical representation using a potential energy function is proposed to model avoidance and it is shown to provide a fair approximation to the empirical observations. We also studied the probability that the individuals disrupt the group by "passing through it" (termed as intrusion). We analyzed the dependence of the parameters of the avoidance model and of the probability of intrusion on groups' social relation and intensity of interaction. We confirmed that the stronger social bonding or interaction intensity is, the more prominent collision avoidance turns out. We also confirmed that the probability of intrusion is a decreasing function of interaction intensity and strength of social bonding. Our results suggest that such variability should be accounted for in models and crowd management in general. Namely, public spaces with strongly bonded groups (e.g. a family-oriented amusement park) may require a different approach compared to public spaces with loosely bonded groups (e.g. a business-oriented trade fair).
ABSTRACT
BACKGROUND: Paraneoplastic pemphigus (PNP), also called paraneoplastic autoimmune multiorgan syndrome (PAMS), is a rare autoimmune disease with mucocutaneous and multi-organ involvement. PNP/PAMS is typically associated with lymphoproliferative or haematological malignancies, and less frequently with solid malignancies. The mortality rate of PNP/PAMS is elevated owing to the increased risk of severe infections and disease-associated complications, such as bronchiolitis obliterans. OBJECTIVES: These guidelines summarize evidence-based and expert-based recommendations (S2k level) for the clinical characterization, diagnosis and management of PNP/PAMS. They have been initiated by the Task Force Autoimmune Blistering Diseases of the European Academy of Dermatology and Venereology with the contribution of physicians from all relevant disciplines. The degree of consent among all task force members was included. RESULTS: Chronic severe mucositis and polymorphic skin lesions are clue clinical characteristics of PNP/PAMS. A complete assessment of the patient with suspected PNP/PAMS, requiring histopathological study and immunopathological investigations, including direct and indirect immunofluorescence, ELISA and, where available, immunoblotting/immunoprecipitation, is recommended to achieve a diagnosis of PNP/PAMS. Detection of anti-envoplakin antibodies and/or circulating antibodies binding to the rat bladder epithelium at indirect immunofluorescence is the most specific tool for the diagnosis of PNP/PAMS in a patient with compatible clinical and anamnestic features. Treatment of PNP/PAMS is highly challenging. Systemic steroids up to 1.5 mg/kg/day are recommended as first-line option. Rituximab is also recommended in patients with PNP/PAMS secondary to lymphoproliferative conditions but might also be considered in cases of PNP/PAMS associated with solid tumours. A multidisciplinary approach involving pneumologists, ophthalmologists and onco-haematologists is recommended for optimal management of the patients. CONCLUSIONS: These are the first European guidelines for the diagnosis and management of PNP/PAMS. Diagnostic criteria and therapeutic recommendations will require further validation by prospective studies.
Subject(s)
Paraneoplastic Syndromes, Nervous System , Paraneoplastic Syndromes , Animals , Rats , Autoimmune Diseases , Neoplasms/complications , Paraneoplastic Syndromes/diagnosis , Paraneoplastic Syndromes/etiology , Paraneoplastic Syndromes/therapy , Paraneoplastic Syndromes, Nervous System/diagnosis , Paraneoplastic Syndromes, Nervous System/etiology , Paraneoplastic Syndromes, Nervous System/therapy , Societies, MedicalABSTRACT
A 39-year-old Caucasian woman affected by Noonan Syndrome (NS) mutated in RAF1 was referred to us with itchy lesions on her limbs that had appeared two months earlier. Clinically, there were multiple umbilicated papules with a hyperkeratotic central plug, localized on the upper and lower limbs (Figure 1, a-b). The patient had no personal history of diabetes mellitus or chronic renal failure, but suffered from hypertrophic cardiomyopathy. Blood tests showed no abnormalities. On histological examination of a skin lesion, an ectatic hair follicle with a hyperkeratotic ostium was observed with fragments of hair, inflammatory cells, and epidermal perforation. A final diagnosis of Kyrle disease (KD) was established. The patient underwent narrowband UVB (NB-UVB) phototherapy with residual atrophic scars (Figure 1, c-d), but with a complete and long-lasting resolution of symptoms. KD belongs to perforating dermatoses (PD), a heterogeneous group of skin diseases characterized by the transepidermal elimination of dermal components. Despite the classification of PD still being under debate, four primary forms are traditionally recognized: reactive perforating collagenosis, elastosis perforans serpiginosum, perforating folliculitis, and KD (1). The typical skin manifestation of KD is an eruption of dome-shaped papules and nodules, with a whitish central keratotic plug, mainly localized on the extremities and the buttocks. Described by Kyrle in 1916, KD is frequently associated with systemic diseases, especially chronic renal failure and diabetes mellitus. Other associated conditions include chronic hepatic disease, internal malignancies, and congestive heart disease (1). Despite the absence of a consensus, the control of the underlying disease remains the first therapeutic target. Both topical (keratolytics, retinoids, and corticosteroids) and systemic treatments (corticosteroids, retinoids, antibiotics, and phototherapy) have been reported to control skin manifestations (2). In our experience, NB-UVB is an effective option as first-line therapy in case of diffuse lesions, both in KD and in other PD (3). NS is a relatively common RASopathy, a heterogenous group of genetic diseases characterized by a defect of the Ras-mitogen-activated protein kinase (Ras-MAPK) pathway, with an estimated prevalence of 1/1000-2500. PTPN11 is the most frequent mutated gene, accounting for 50% of cases, but more than ten genes have been identified as causing NS (4). Classical features include a distinctive facial dysmorphism, short stature, pulmonic stenosis, and other anomalies of different organs. The skin is commonly involved. Keratinization disorders and hair abnormalities such as keratosis pilaris, ulerythema ophryogenes, wavy or curly hair, and scarce scalp hair, are often described. Other cutaneous signs include easy bruising, skin hyperlaxity, multiple lentigines, and café-au-lait spots (5). To the best of our knowledge, no cases of KD in patients with NS have been previously reported to date. The exact etiopathogenesis of KD is not clear, but it has been hypothesized that systemic diseases, such as diabetes and chronic renal failure, can cause a deposit of substances or dermis alterations, which triggers the inflammatory process with subsequent transepidermal extrusion (1). In our patient, we ruled out all the causes commonly associated with KD. It is however possible that this manifestation could be a direct result of the patient's illness. Our patient suffered from diffuse keratosis pilaris, and an abnormal epidermal keratinization with a secondary inflammatory dermic response is among the suggested possible pathogenetic mechanisms of KD (1). On the other hand, the hyperlaxity and fragility of the skin typical of NS suggest the presence of altered connective tissue, which could trigger an abnormal keratinization and, subsequently, the transepidermal extrusion, as well as perforating elastosis, which is associated with genetic connective tissue diseases (1). Moreover, our patient suffered from a cardiac disease, another condition associated with KD (5). Although these explanations have their appeal, there is currently insufficient evidence of a link between KD and NS, and it will be necessary to collect additional data to confirm this hypothesis.
Subject(s)
Abnormalities, Multiple , Darier Disease , Diabetes Mellitus , Eyebrows/abnormalities , Kidney Failure, Chronic , Noonan Syndrome , Female , Humans , Adult , Noonan Syndrome/complications , Noonan Syndrome/diagnosis , Noonan Syndrome/therapy , Adrenal Cortex Hormones , RetinoidsABSTRACT
Pedestrians threading through a crowd is a striking example of coordinated actions. Mutual anticipation between pedestrians is a candidate mechanism underlying such coordination. To examine this possibility, we experimentally intervened pairs of pedestrians performing simple avoidance tasks. Pedestrians in the baseline condition spontaneously coordinated their walking speed and angle until passing one another. Visually distracting one of the pedestrians decreased the level of behavioral coordination. Importantly, blocking the pedestrians' gaze information alone did not alter their walking. These results indicate that spontaneous coordination requires mutual anticipation. Eye movement analysis showed that the direction of a pedestrian's gaze changed depending on the uncertainty of the oncoming pedestrian's motion, and that pedestrians tended to look ahead toward the ultimate passing direction before they actually walked in that direction. We propose that body motion cues may be sufficient and available for implicit negotiation of potential future motions.
ABSTRACT
Since the beginning of the covid-vaccine campaign, a lot of local and systemic dermatologic reactions happening after the administration of Coronavirus disease 2019 (COVID-19) vaccines have been described, even if their exact biological mechanism is still debated. In this paper we report 4 cases of cutaneous manifestations arose within ten days after the first dose of messenger RNA (mRNA)-based COVID-19 vaccination: one case of giant urticaria, one case of head and neck redness and two cases of Erythema Multiforme (EM). In our experience these reactions were mild, transient and all of them resolved, not recurring after the second dose, so these manifestations shouldn't be considered as an absolute contraindication to the second dose of vaccine, that to date is fundamental.
ABSTRACT
INTRODUCTION: Angiosarcomas (AS) are rare and aggressive neoplasms originating from the endothelium: they represent less than 2% of all soft tissue sarcomas and usually have a poor prognosis. Although more often primary, different risk factors have been described and some cases are associated with vascular surgery. Materials and Methods: We present the case of an 84-year-old man who developed an AS on his thigh 3 years after a popliteal bypass with autologous saphenous vein. We performed a thorough review of the literature describing the main characteristics of the 25 cases (including ours) of AS associated with vascular surgery reported from 1981 to 2022. Results: Most of the patients were males (21 men vs 4 women) with a range age of 50-84 years. Most of AS are associated with Dacron grafts (12 cases), the overall mean time to onset is 7.8 years after surgery. The most common presenting symptoms are pain (20 cases) and weight loss (10 cases), while cutaneous presentation is uncommon; indeed, violaceous and painful papules, plaques, nodules, and skin ulceration have been found in 3 cases only. Due to unspecific symptoms, differential diagnosis is often difficult and a biopsy for histological confirmation is mandatory. Conclusion: Even if it seems to be a very rare complication, AS should always be considered in patients with compatible symptoms and who have undergone vascular surgery in the past.