Reactive granulomatous dermatitis as a histological pattern including manifestations of interstitial granulomatous dermatitis and palisaded neutrophilic and granulomatous dermatitis: a study of 52 patients.

BACKGROUND: Confusion exists regarding interstitial granulomatous dermatitis (IGD) and palisaded neutrophilic and granulomatous dermatitis (PNGD). OBJECTIVE: To determine whether IGD and PNGD are two different entities, or whether they must be considered as two subtypes of the same reactive pattern, and thus whether the unification of the nomenclature is necessary. METHODS: Observational retrospective multicentre study of patients with IGD and PNGD evaluated between 1999 and 2019 and review of their clinical and histological features. RESULTS: We identified 52 patients (38 women and 14 men). Clinical and histological findings of IGD were observed in 88.4% of cases. The most common cutaneous lesions were plaques/macules (IGD) or annular plaques and papules/nodules (PNGD), located mostly on the limbs and trunk. The rope sign was developed in two patients with IGD that associated autoimmune disorders. Similar associated comorbidities (75%) were found in both entities, mainly autoimmune diseases (53.8%). In IGD, the infiltrate was predominantly lympho-histiocytic. Neutrophilic infiltrates, karyorrhexis and skin lesions with limited clinical course were mainly associated with PNGD biopsies. In biopsies with a limited recurrent course, a predominant lymphocytic inflammatory infiltrate was found. Collagen degeneration was present in 75.9% of cases. The floating sign was observed only in IGD type patients (63%). Overlapping histological findings were found in one fourth of cases, especially between IGD and interstitial granuloma annulare. Interface dermatitis, apparently unrelated to drug intake, was observed in 4 cases of IGD. CONCLUSION: We support the term reactive granulomatous dermatitis to unify both the clinical and histological findings of IGD and PNGD, and the overlapping between IGD and interstitial granuloma annulare. According to this, a spectrum of histological changes will be found depending on the clinical course of the skin lesions.

The involvement of ADAM10 in acantholysis in mucocutaneous pemphigus vulgaris depends on the autoantibody profile of each patient.

BACKGROUND: Acantholysis in pemphigus vulgaris (PV) may be triggered by desmoglein (Dsg) and non-Dsg autoantibodies. The autoantibody profile of each patient results in distinct intracellular signalling patterns. OBJECTIVES: Based on our previous findings, we aimed to elucidate whether PV acantholysis in a mouse model may be mediated by activation of a disintegrin and metalloproteinase 10 (ADAM10). METHODS: We used three PV-IgG fractions from different patients containing high or low levels of anti-Dsg1 and anti-Dsg3 antibodies, and the presence or not of anti-desmocollin (Dsc) antibodies, using a passive transfer mouse model of PV. RESULTS: Although all of the PV-IgG fractions produced suprabasal acantholysis, only those containing anti-Dsg1/3, but not anti-Dsc2/3 antibodies, induced ADAM10 activation in a Src-dependent way, and an increase in the epidermal growth factor (EGF) receptor ligands EGF and betacellulin (BTC). In contrast, the presence of anti-Dsc2/3 antibodies, in addition to anti-Dsg1/3, triggered earlier and ADAM10-independent epidermal detachment, with no increase in EGF and BTC, which was associated with an earlier and more intense acantholysis. CONCLUSIONS: All PV-IgG fractions produced suprabasal acantholysis, but our results reveal that depending on the levels of anti-Dsg antibodies or the presence of non-Dsg antibodies, such as anti-Dsc, more severe cell-cell epidermal detachment will occur at different times, and in an ADAM10-dependent manner or not. Acantholysis in these different groups of patients with PV may be a consequence of the activation of specific intracellular mechanisms downstream of Autoantibodies binding to Dsg or non-Dsg proteins, and therefore more specific therapeutic approaches in PV should be used. What's already known about this topic? Suprabasal acantholysis in pemphigus vulgaris (PV) may be triggered by both desmoglein (Dsg) and non-Dsg autoantibodies. The autoantibody profile of each patient is associated with a distinct intracellular signalling pattern. What does this study add? In patients with PV with anti-Dsg3 and anti-Dsg1, but not anti-desmocollin (Dsc)3 antibodies, ADAM10 activation is induced in an Src-dependent way, together with an increase in the epidermal growth factor receptor (EGFR) ligands EGF and betacellulin. The presence of anti-Dsc3 antibodies triggers an earlier and ADAM10-independent acantholysis, without increasing EGFR ligands, and is associated with more severe epidermal detachment. Lower levels of anti-Dsc3 antibodies are associated with less severe acantholysis. What is the translational message? In some patients with PV, the severity and the timing for cell-cell detachment seem to depend on the level of anti-Dsg1/3 antibodies, although other as yet uncharacterized antibodies may also participate. These patients with PV would exhibit inhibition of acantholysis by Src, ADAM10, EGF and EGFR inhibitors. In other patients, the presence of non-Dsg antibodies, such as anti-Dsc2/3, would produce an earlier and more severe ADAM10-independent suprabasal acantholysis.

Mucocutaneous manifestations of cocaine abuse: a review.

Cocaine is an alkaloid extracted from the leaves of the Erythroxylum coca plant that emerged in the 1970s as a fashionable drug among members of certain social backgrounds. Cocaine abuse is a problem of current interest, which is mostly hidden and underdiagnosed, but dramatically widespread among all socio-economic strata, and with an incidence which is increasing at an alarming rate. There are 1.5 million cocaine consumers in the USA. In Spain, the prevalence of consumption among the population between 15 and 65 years old is higher, reaching 3.1%. Because of this, it seems important to understand and recognize all the mucocutaneous manifestations of cocaine abuse which have been reported in the literature to clarify and to help dermatologists in their daily practice. In this article, we describe the principal mucocutaneous manifestations of cocaine abuse and we review isolated case reports which have been published in the literature. Because the dermatologist may deal with an unknown problem as well as with an already well-known history of cocaine abuse, it seems logical to separate the mucocutaneous manifestations into those which are frequent and highly suggestive, such as those caused by vascular injury, damage to mucosal membranes, infectious diseases or neutrophilic dermatosis, especially when suffered by young people and in consonance with other systemic manifestations and, those which have been reported in the literature as isolated case reports. We also summarize the main aspects of its pathogeny, principal pharmacodynamic and pharmacokinetic characteristics, and diagnostic tools.

In utero delivery of rAAV2/9 induces neuronal expression of the transgene in the brain: towards new models of Parkinson's disease.

Animal models are essential tools for basic pathophysiological research as well as validation of therapeutic strategies for curing human diseases. However, technical difficulties associated with classical transgenesis approaches in rodent species higher than Mus musculus have prevented this long-awaited development. The availability of viral-mediated gene delivery systems in the past few years has stimulated the production of viruses with unique characteristics. For example, the recombinant adeno-associated virus serotype 9 (rAAV2/9) crosses the blood-brain barrier, is capable of transducing developing cells and neurons after intravenous injection and mediates long-term transduction. Whilst post-natal delivery is technically straightforward, in utero delivery bears the potential of achieving gene transduction in neurons at embryonic stages during which the target area is undergoing development. To test this possibility, we injected rAAV2/9 carrying either A53T mutant human α-synuclein or green fluorescent protein, intracerebroventricularly in rats at embryonic day 16.5. We observed neuronal transgene expression in most regions of the brain at 1 and 3 months after birth. This proof-of-concept experiment introduces a new opportunity to model brain diseases in rats.

Exploring beyond the oral mucosa in patients affected with autoimmune blistering diseases: the importance of endoscopic procedures.

Autoimmune blistering diseases (AIBD) comprise several entities characterized by the presence of autoantibodies targeted against structural proteins either in desmosomes or in the dermoepidermal junction of polystratified squamous epithelium. Patients develop blisters, erosions in cutaneous surfaces or mucosas. Diagnosis is based on the characteristic mucocutaneous lesions, the typical findings on histological studies and direct immunofluorescence assays, and the presence of specific autoantibodies against the epidermal antigens. It may not be possible for dermatologists to appropriately explore the nose and throat (NT). Thus, a clinical exploration by endoscopic procedures of NT may be a useful tool during the conventional dermatological exam. The aims of this review are to draw attention to the most frequent NT manifestations in AIBD patients, and underline the utility of endoscopic procedures to achieve a more successful and rationale management of patients. Additionally, we will provide brief information related to the anatomical structures and type of epithelium in NT areas which may explain the extent and type of NT involvement in AIBD. Endoscopic exploration in AIBD patients is important for several reasons. Firstly, it will allow the real NT mucosal involvement in each patient to be determined, thus making a differential diagnosis during the endoscopic exam possible, based on the localization of mucosal lesions. Secondary mucosal morbidity can also be ruled out. Secondly, the clinical response to treatment may be established, especially in NT mucosa, as these are anatomical areas subjected to important local traumas, and physiological functions such as breathing, swallowing, speech production and phonation may be damaged. Therefore, a multidisciplinary management in AIBD is mandatory by both dermatologists and otorhinolaryngologists, adding the clinical exploration by endoscopic procedures of NT to the conventional dermatological exam in all AIBD patients, irrespective of whether they exhibit associated symptoms.

Focal hyperhidrosis secondary to eccrine naevus successfully treated with botulinum toxin type A.

Eccrine naevus (EN) is a rare skin hamartoma included in the organoid group of epidermal naevi, histologically defined as focal hyperplasia and/or hypertrophy of eccrine glands. Clinically, EN usually presents as hyperhidrotic patches with no visible skin changes, frequently located on the forearms. The decision to treat EN or not usually depends on the grade of hyperhidrosis, but there is no therapeutic consensus because of the rarity of this condition. We present a case diagnosed as EN in an adult patient with severe localized hyperhidrosis, which was successfully treated with botulinum toxin.

Epidermolysis bullosa acquisita: a retrospective analysis of 12 patients evaluated in four tertiary hospitals in Spain.

BACKGROUND: Epidermolysis bullosa acquisita is an exceedingly rare subepidermal blistering disease caused by antibodies against type VII collagen. Studies summarizing the clinical and immunological features of this disease in large series of patients are scarce. OBJECTIVES: To analyse the clinical and immunopathological characteristics, treatment responses and outcomes of 12 patients with epidermolysis bullosa acquisita from four tertiary hospitals in Spain. METHODS: An extensive retrospective review of clinical charts. RESULTS: The mean age of onset was 48 years and the mean delay to diagnosis was 20·75 months. The classical phenotype occurred in 42% of cases, inflammatory in 42% and mixed in 17%. Mucosal involvement was present in 75%. Linear IgG deposition along the basement membrane zone was consistently present on direct immunofluorescence examination. Indirect immunofluorescence study was positive in 67% of the cases. Frequently associated diseases were neoplasms (25%), inflammatory bowel disease (25%), hepatitis C virus infection (17%) and thyroid dysfunction (17%). Therapeutic responses were variable. CONCLUSIONS: The prevalence of neoplasms was similar to that seen in inflammatory bowel disease. Multicentric prospective studies including larger numbers of patients are required for a better knowledge and management of this disease.

Staphylococcus aureus genomic pattern and atopic dermatitis: may factors other than superantigens be involved?

The purpose of this investigation was to compare the genotypic profiles of Staphylococcus aureus isolated from atopic dermatitis (AD) patients and from control subjects, and to study the relationship between clinical severity, immune response, and genomic pattern of S. aureus isolated from AD patients. We selected 32 patients with AD and S. aureus skin colonization and 31 atopic controls with no history of AD who where asymptomatic carriers of S. aureus. Microarray-based genotyping was performed on S. aureus isolates. In AD patients, clinical severity was assessed using the Scoring Atopic Dermatitis index and total IgE levels and staphylococcal superantigen-specific IgE levels (SEA, SEB, SEC, TSST1) were determined. The genes lukE, lukD, splA, splB, ssl8, and sasG were more frequent in isolates from AD patients. CC30 was more common in isolates from atopic controls than in AD patients. There was a correlation between total IgE and clinical severity, but an association between clinical severity, immune response, and the presence of S. aureus superantigen genes, including enterotoxin genes, could not be demonstrated. Finally, a correlation was found between AD severity and other S. aureus genes, such as sasG and scn. S. aureus factors besides superantigens could be related to the worsening and onset of AD.

Drug-induced lupus erythematosus.

Drug-induced lupus erythematosus (DILE) refers to a condition whose clinical, histological, and immunological features are similar to those seen in idiopathic lupus erythematosus but that occurs when certain drugs are taken and resolves after their withdrawal. Over 90 drugs have been linked to DILE to date and the list is growing. Like idiopathic lupus erythematosus, DILE has systemic, subacute cutaneous, and chronic cutaneous forms. A correct diagnosis is very important, as this condition usually resolves after withdrawal of the offending drug.

Onecut factors control development of the Locus Coeruleus and of the mesencephalic trigeminal nucleus.

The Locus Coeruleus (LC), the main noradrenergic nucleus in the vertebrate CNS, contributes to the regulation of several processes including arousal, sleep, adaptative behaviors and stress. Regulators controlling the formation of the LC have been identified but factors involved in its maintenance remain unknown. Here, we show that members of the Onecut (OC) family of transcription factors, namely HNF-6, OC-2 and OC-3, are required for maintenance of the LC phenotype. Indeed, in embryos lacking any OC proteins, LC neurons properly differentiate but abnormally migrate and eventually lose their noradrenergic characteristics. Surprisingly, the expression of Oc genes in these neurons is restricted to the earliest differentiation stages, suggesting that OC factors may regulate maintenance of the LC in a non cell-autonomous manner. Accordingly, the OC factors are present throughout development in a population directly adjacent to the LC, the rhombencephalic portion of the mesencephalic trigeminal nucleus (MTN). In the absence of OC factors, rhombencephalic MTN neurons fail to be generated, suggesting that OC proteins cell-autonomously control their production. Hence, we propose that OC factors are required at early developmental stages for differentiation of the MTN neurons that are in turn necessary for maintenance of the LC.

Rituximab in dermatology.

Rituximab was introduced into clinical practice as a medication with considerable potential. Its use in patients with B-cell lymphoma and rheumatoid arthritis revealed numerous indications in autoimmune diseases, many of which involve the skin, thus requiring dermatologists to become familiar with both the characteristics of anti-CD20 antibodies and the role of B cells in multiple skin diseases. Thanks to these developments, we will be able to use rituximab more frequently and appropriately in our patients and draw up consensus guidelines based on large case series. In other words, establishing the indications for rituximab will make it possible to shorten disease course and reduce morbidity due to more specific drugs.

Study of oral, ear, nose and throat involvement in pemphigus vulgaris by endoscopic examination.

BACKGROUND: Pemphigus vulgaris (PV) is an autoimmune blistering skin disorder characterized by the presence of suprabasal acantholysis and autoantibodies against desmoglein 3. There are two different clinical forms: mucocutaneous (MCPV) and mucosal (MPV). However, little is known about PV lesions in oral, ear, nose and throat (OENT) areas produced by the very dynamic of the anatomical structures involved in the functions of the aerodigestive tract. OBJECTIVES: To investigate the pattern of OENT manifestations in PV, and their relationship with physiological traumatic mechanisms in stratified squamous epithelial structures. METHODS: A prospective analysis of 40 patients diagnosed with MCPV (22 patients) or MPV (18 patients) was carried out at the University Clinic of Navarra. OENT manifestations were evaluated in all patients endoscopically. OENT involvement was divided into anatomical areas. RESULTS: The most frequent symptom was pain, mainly on oral mucosa (87·5%). Buccal mucosa (90%), posterior wall of pharynx (67·5%), upper edge of epiglottis (85%) and nasal vestibule (70%) were the areas most frequently affected in the OENT mucosa. These localizations were related to physiological traumatic mechanisms in polystratified squamous epithelial structures. CONCLUSIONS: OENT endoscopy should be included in the examination of all patients with PV. Knowledge of the most frequent localizations of active lesions on OENT mucosa in PV will help us to interpret more efficiently the findings from OENT endoscopy. Also, information related to traumatic physiological mechanisms on OENT areas must be offered to patients in order to avoid the appearance of new active PV lesions.

Prognostic time dependence of deletions affecting codons 557 and/or 558 of KIT gene for relapse-free survival (RFS) in localized GIST: a Spanish Group for Sarcoma Research (GEIS) Study.

BACKGROUND: To assess whether deletions involving codons 557 and/or 558 (critical deletions) of exon 11 of KIT are relevant in the prognosis of relapse-free survival (RFS) in gastrointestinal stromal tumor (GIST) patients with a long follow-up. PATIENTS AND METHODS: A univariate and multivariate analysis for RFS were carried out on 162 localized GIST patients over the entire follow-up period and over the intervals 0-4 years and >4 years. Factors assessed among others were Fletcher/National Institutes of Health and Miettinen-Lasota/Armed Forces Institute of Pathology (M-L/AFIP) risk categories, critical deletions and non-deletion-type mutation (NDTM) within exon 11 of KIT. RESULTS: Multivariate analyses revealed that M-L/AFIP [relative risk (RR) 11.45, confidence interval (CI) 4.40-29.76, for the high-risk subgroup and RR 5.97, CI 2.09-17.06, for the intermediate subgroup] and critical deletions (RR 3.05, CI 1.59-5.85) were independent prognostic factors for RFS for the first 4 years and for the entire follow-up period. Beyond 4 years, the high-risk M-L/AFIP subgroup (RR 8.12, CI 1.48-44.4) and NDTM (RR 6.42, CI 1.17-35.12) were independent prognostic factors for RFS. The median follow-up was 84 months. CONCLUSION: Critical deletions represent a time-dependent prognostic factor limited to the first 4 years after surgery, which could help identify a subset with higher and earlier risk for relapse in GIST patients.