Anti-SAE autoantibody in dermatomyositis: original comparative study and review of the literature.

OBJECTIVE: Among specific autoantibodies in DM, the anti-small ubiquitin-like modifier activating enzyme (SAE) antibody is rare. We aim to describe the clinical characteristics, cancer prevalence, and muscle pathology of anti-SAE-positive DM. METHODS: Patients with a diagnosis of DM and sera positive for the anti-SAE antibody were recruited from 19 centres in this retrospective observational study. The available muscular biopsies were reviewed. We conducted a comparison with anti-SAE-negative DM and a review of the literature. RESULTS: Of the patients in the study (n = 49), 84% were women. Skin involvement was typical in 96% of patients, with 10% having calcinosis, 18% ulceration and 12% necrosis; 35% presented with a widespread skin rash. Muscular disease affected 84% of patients, with mild weakness [Medical Research Council (MRC) scale 4 (3, 5)], although 39% of patients had dysphagia. Muscular biopsies showed typical DM lesions. Interstitial lung disease was found in 21% of patients, mainly with organizing pneumonia pattern, and 26% of patients showed dyspnoea. Cancer-associated myositis was diagnosed in 16% of patients and was responsible for the majority of deaths, its prevalence being five times that of the general population. IVIG therapy was administered to 51% of the patients during the course of the disease. Comparison with anti-SAE-negative DM (n = 85) showed less and milder muscle weakness (P = 0.02 and P = 0.006, respectively), lower creatinine kinase levels (P < 0.0001) and less dyspnoea (P = 0.003). CONCLUSION: Anti-SAE positive DM is a rare subgroup associated with typical skin features but a potentially diffuse rash, a mild myopathy. Interstitial lung disease defines an organizing pneumonia pattern. Cancer associated DM prevalence is five times that of the general population. TRIAL REGISTRATION: ClinicalTrials.gov, http://clinicaltrials.gov, NCT04637672.

Dermatoscopic and clinical features of congenital or congenital-type nail matrix nevi: A multicenter prospective cohort study by the International Dermoscopy Society.

BACKGROUND: Congenital nail matrix nevi (NMN) are difficult to diagnose because they feature clinical characteristics suggestive of adult subungual melanoma. Nail matrix biopsy is difficult to perform, especially in children. OBJECTIVE: To describe the initial clinical and dermatoscopic features of NMN appearing at birth (congenital) or after birth but before the age of 5 years (congenital-type). METHODS: We conducted a prospective, international, and consecutive data collection in 102 hospitals or private medical offices across 30 countries from 2009 to 2019. RESULTS: There were 69 congenital and 161 congenital-type NMNs. Congenital and congenital-type NMN predominantly displayed an irregular pattern of longitudinal microlines (n = 146, 64%), reminiscent of subungual melanoma in adults. The distal fibrillar ("brush-like") pattern, present in 63 patients (27.8%), was more frequently encountered in congenital NMN than in congenital-type NMN (P = .012). Moreover, congenital NMN more frequently displayed a periungual pigmentation (P = .029) and Hutchinson's sign (P = .027) than did congenital-type NMN. LIMITATIONS: Lack of systematic biopsy-proven diagnosis and heterogeneity of clinical and dermatoscopic photographs. CONCLUSION: Congenital and congenital-type NMN showed worrisome clinical and dermatoscopic features similar to those observed in adulthood subungual melanoma. The distal fibrillar ("brush-like") pattern is a suggestive feature of congenital and congenital-type NMN.

The scalp hair collar and tuft signs: A retrospective multicenter study of 78 patients with a systematic review of the literature.

BACKGROUND: Hair collar sign (HCS) and hair tuft of the scalp (HTS) are cutaneous signs of an underlying neuroectodermal defect, but most available data are based on case reports. OBJECTIVE: We sought to define the clinical spectrum of HCS and HTS, clarify the risk for underlying neurovascular anomalies, and provide imaging recommendations. METHODS: A 10-year multicenter retrospective and prospective analysis of clinical, radiologic, and histopathologic features of HCS and HTS in pediatric patients was performed. RESULTS: Of the 78 patients included in the study, 56 underwent cranial and brain imaging. Twenty-three of the 56 patients (41%) had abnormal findings, including the following: (1) cranial/bone defect (30.4%), with direct communication with the central nervous system in 28.6%; (2) venous malformations (25%); or (3) central nervous system abnormalities (12.5%). Meningeal heterotopia in 34.6% (9/26) was the most common neuroectodermal association. Sinus pericranii, paraganglioma, and combined nevus were also identified. LIMITATIONS: The partial retrospective design and predominant recruitment from the dermatology department are limitations of this study. CONCLUSIONS: Infants with HCS or HTS are at high risk for underlying neurovascular anomalies. Magnetic resonance imaging scans should be performed in order to refer the infant to the appropriate specialist for management.

Nevus anemicus in neurofibromatosis type 1: a potential new diagnostic criterion.

BACKGROUND: Children with multiple café-au-lait macules (CALMs) may be followed for years before a second National Institutes of Health clinical criterion of neurofibromatosis type 1 (NF1) develops to confirm the diagnosis. OBJECTIVE: We sought to assess the prevalence of nevus anemicus (NA) in NF1 and its association with neuro-ophthalmologic complications. METHODS: This was a prospective multicenter case-control study of 210 consecutive patients with multiple CALMs. Patients with NF1 were matched for age, sex, and center with control subjects. We documented the number, location, and morphologic appearance of NA; dermatologic features of NF1; magnetic resonance imaging results; and family history. RESULTS: In all, 77 (51%) patients with NF1 had NA compared with 6 (2%) control subjects. NA was not detected in 26 patients with other genodermatoses associated with CALMs. Patients with NF1 and NA were younger than those without NA (median age: 17 years) (P = .002). NA was mostly localized to the upper anterior aspect of the chest. NA was not significantly linked with other clinical manifestations of NF1, including optic glioma and unidentified bright objects. LIMITATIONS: A potential referral bias associated with tertiary care centers is a limitation. CONCLUSIONS: NA appears to have a high prevalence and specificity in NF1 and might serve as a marker for NF1 in children with multiple CALMs.

Lipoatrophic connective tissue panniculitis.

Many causes of what was formerly called Weber-Christian and Rothmann-Makai diseases are being clarified as specific forms of panniculitis. Among them, an autoimmune process involving the subcutaneous fat without criteria for another defined disorder coined "connective tissue panniculitis" by Winckelman et al in 1980 has been described. We describe this disease in a 4-year-old boy who presented with multiple subcutaneous inflammatory nodules that extended in an annular fashion, resolved leaving lipoatrophy, with recurrence 8 years later. The histologic findings were consistent with a granulomatous lipophagic panniculitis. We review previous reports and emphasize the limited therapeutic options, chronic evolution, severe esthetic sequelae and possible association with other autoimmune disorders of this uncommon condition.

Decreased expression of thymidine phosphorylase/platelet-derived endothelial cell growth factor in basal cell carcinomas.

Thymidine phosphorylase (TP)/platelet-derived endothelial cell growth factor is associated with tumor angiogenesis. We evaluated the TP mRNA and protein expression in basal cell carcinomas (BCC) and in various skin tumors including numerous BCC histological simulants. Immunohistochemistry was performed on 99 paraffin sections of formalin-fixed skin tumors using monoclonal antibodies (mAb) against TP. TP mRNA levels were measured by real time RT-PCR in whole BCCs (wBCC) and laser capture microdissected (LCM) BCC tumor cells. TP immunostaining was negative in all BCC variants and in most of the benign trichogeneic tumors studied. By contrast, TP was constantly immunodetected in actinic keratosis (AK), squamous cell carcinomas (SCC), syringomatous carcinomas (SC), basosquamous carcinomas (BSC) and melanomas. TP mRNA levels were low and statistically not different in wBCC and normal skin but were strongly downregulated in LCM-BCC as compared with LCM-normal epidermis. We concluded that (i) anti-TP mAb is an useful marker to differentiate BCC from AK, SCC, BSC and SC but not from trichoblastic tumors, (ii) the lack of TP protein expression in BCC tumoral cells is linked to transcriptional regulatory mechanisms, (iii) the low TP mRNA levels in whole BCC may be related to the low intra-tumoral microvessel density, the slow growth and the very low metastatic potential of these tumors.

Superficial lymphangitis after arthropod bite: a distinctive but underrecognized entity?

BACKGROUND: Acute bacterial lymphangitis is a common occurrence after skin damage. This diagnosis is often made in case of red linear streaks after arthropod bites, leading to the prescription of oral antibiotics. In this setting, noninfectious superficial lymphangitis after arthropod bites, an eruption rarely mentioned in the medical literature, appears as a diagnostic challenge. OBJECTIVE: Our purpose was to study the clinical and histopathological features of this underrecognized condition. METHODS: We collected the observations of six consecutive patients seen between the years 2003 and 2006, who developed an acute linear erythematous eruption along lymphatic vessels, mimicking common bacterial lymphangitis. Standard histological examinations were completed by immunopathological staining using the monoclonal antibody D2-40, a highly selective marker of lymphatic endothelium. Extensive review of the literature about acute noninfectious superficial lymphangitis was performed. RESULTS: The clinical presentation and histological findings excluded an infectious etiology and suggested superficial lymphangitis after an arthropod bite in all the observations. CONCLUSIONS: This article analyzes the clinical and histological features of noninfectious superficial lymphangitis after arthropod bite, a benign underrecognized condition mimicking common bacterial lymphangitis. Physicians should be aware of this benign reaction to avoid the useless prescription of antibiotics.