Dermatoscopy in Diagnosis of Cutaneous Myiasis Arising in Pemphigus Vulgaris Lesions.
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ABSTRACT: Myiasis, infestation of live human and vertebrate animals by larvae, can complicate ulcers and open wounds. Although myiasis occurs in neglected erosions of pemphigus, such a complication is not documented in the literature. Herein, we report a case of myiasis complicating pemphigus vulgaris and describe its dermatoscopic features.
Project description:Background: Many patients with pemphigus vulgaris (PV) in India present with predominant/exclusive oral mucosal lesions. Current validated scoring systems for pemphigus do not adequately represent the clinical variability of oral lesions. Objective: To develop and validate a novel scoring system exclusively for oral lesions in PV. Methods: In this cross-sectional study, the Delphi method was used to build an initial scale that was administered in 115 patients with PV. Exploratory factor analysis was used to examine the underlying factor structure of the new scale. The psychometric properties of the new scale were studied. Correlations between the new scale and Autoimmune Bullous Skin Disorder Intensity Score (ABSIS), Pemphigus Disease Area Index (PDAI), and Physician Global Assessment (PGA) were also assessed. Results: Content validity of the initial scale was established with an average content validity index (CVI) of 0.8. Exploratory factor analysis resulted in a 3-factor structure with a total of 9 items. Corrected item-total correlation, a measure of data quality, was more than 0.30 for all items in the new oral mucosal scale-Pemphigus Oral Lesions Intensity Score (POLIS). Significant correlations were observed between POLIS and oral ABSIS (r = 0.85, p < 0.001), mucosal PDAI (r = 0.70, p < 0.001), and PGA (r = 0.60, p < 0.001). POLIS was also reliable with good internal consistency (Cronbach's ? = 0.86) and strong inter-rater agreement. Limitations: The study cohort included participants from a single center. Usability and time taken to administer the scale were not assessed. Conclusions: The new scale, POLIS, has adequate validity and reliability. It includes both quality of life and clinical disease severity parameters, assessing disease severity holistically. Further studies evaluating the scale's responsiveness to change are in progress.
Project description:Autoimmune bullous disorders are a heterogeneous spectrum of skin disorders characterized by the production of autoantibodies against adhesion molecules of the skin. The 2 major groups of diseases are “pemphigus diseases” and “autoimmune bullous diseases of the pemphigoid type.” Pemphigus diseases are a group of autoimmune blistering diseases of the skin and mucous membranes characterized by intraepithelial cleft and acantholysis. The main subtypes of pemphigus include pemphigus vulgaris, pemphigus foliaceus, and paraneoplastic pemphigus. Diagnosis is based on clinical manifestations and confirmed with histological, immunofluorescence, and serological testing. Recently multivariant enzyme-linked immunosorbent assay systems have been developed as practical screening tools for patients with suspected autoimmune bullous dermatoses. The current first-line treatment of pemphigus is based on systemic corticosteroids that are often combined with immunosuppressive adjuvants, such as azathioprine, mycophenolate mofetil, and the anti-CD20 monoclonal antibody rituximab, usually at initiation of treatment. Rituximab efficacy is higher when it is administered early in the course of the disease. Therefore, it should be used as first-line treatment to improve efficacy and reduce cumulative doses of corticosteroids and their side effects. Treatment of bullous pemphigoid is based on disease extension. Localized and mild forms can be treated with superpotent topical corticosteroids or with nonimmunosuppressive agents. In patients with generalized disease or whose disease is resistant to the treatments described above, systemic corticosteroids are preferred and effective. Adjuvant immunosuppressants are often combined with steroids for their steroid-sparing effect.
Project description:Pemphigus vulgaris (PV) is a mucocutaneous blistering disease characterized by IgG autoantibodies against the stratified squamous epithelium. Current understanding of PV pathophysiology does not explain the mechanism of acantholysis in patients lacking desmoglein antibodies, which justifies a search for novel targets of pemphigus autoimmunity. We tested 264 pemphigus and 138 normal control sera on the multiplexed protein array platform containing 701 human genes encompassing many known keratinocyte cell-surface molecules and members of protein families targeted by organ-non-specific PV antibodies. The top 10 antigens recognized by the majority of test patients' sera were proteins encoded by the DSC1, DSC3, ATP2C1, PKP3, CHRM3, COL21A1, ANXA8L1, CD88 and CHRNE genes. The most common combinations of target antigens included at least one of the adhesion molecules DSC1, DSC3 or PKP3 and/or the acetylcholine receptor CHRM3 or CHRNE with or without the MHC class II antigen DRA. To identify the PV antibodies most specific to the disease process, we sorted the data based on the ratio of patient to control frequencies of antigen recognition. The frequency of antigen recognition by patients that exceeded that of control by 10 and more times were the molecules encoded by the CD33, GP1BA, CHRND, SLC36A4, CD1B, CD32, CDH8, CDH9, PMP22 and HLA-E genes as well as mitochondrial proteins encoded by the NDUFS1, CYB5B, SOD2, PDHA1 and FH genes. The highest specificity to PV showed combinations of autoantibodies to the calcium pump encoded by ATP2C1 with C5a receptor plus DSC1 or DSC3 or HLA-DRA. The results identified new targets of pemphigus autoimmunity. Novel autoantibody signatures may help explain individual variations in disease severity and treatment response, and serve as sensitive and specific biomarkers for new diagnostic assays in PV patients.
Project description:BackgroundA number of autoimmune diseases have been clinically and pathologically characterized. In contrast, target antigens have been identified only in a few cases and, in these few cases, the knowledge of the exact epitopic antigenic sequence is still lacking. Thus the major objective of current work in the autoimmunity field is the identification of the epitopic sequences that are related to autoimmune reactions. Our labs propose that autoantigen peptide epitopes able to evoke humoral (auto)immune response are defined by the sequence similarity to the host proteome. The underlying scientific rationale is that antigen peptides acquire immunoreactivity in the context of their proteomic similarity level. Sequences uniquely owned by a protein will have high potential to evoke an immune reaction, whereas motifs with high proteomic redundancy should be immunogenically silenced by the tolerance phenomenon. The relationship between sequence redundancy and peptide immunoreactivity has been successfully validated in a number of experimental models. Here the hypothesis has been applied to pemphigus diseases and the corresponding desmoglein autoantigens.MethodsDesmoglein 3 sequence similarity analysis to the human proteome followed by dot-blot/NMR immunoassays were carried out to identify and validate possible epitopic sequences.ResultsComputational analysis led to identifying a linear immunodominant desmoglein-3 epitope highly reactive with the sera from Pemphigus vulgaris as well as Pemphigus foliaceous. The epitopic peptide corresponded to the amino acid REWVKFAKPCRE sequence, was located in the extreme N-terminal region (residues 49 to 60), and had low redundancy to the human proteome. Sequence alignment showed that human desmoglein 1 and 3 share the REW-KFAK-RE sequence as a common motif with 75% residue identity.ConclusionThis study 1) validates sequence redundancy to autoproteome as a main factor in shaping desmoglein peptide immunogenicity; 2) offers a molecular mechanicistic basis in analyzing the commonality of autoimmune responses exhibited by the two forms of pemphigus; 3) indicates possible peptide-immunotherapeutical approaches for pemphigus diseases.
Project description:Pemphigus vulgaris (PV) is a life-threatening autoimmune blistering skin disease characterized by detachment of keratinocytes (acantholysis). It has been proposed that PV IgG might trigger signaling and that this process may lead to acantholysis. Indeed, we recently identified a rapid and dose-dependent phosphorylation of p38 mitogen-activated protein kinase (p38MAPK) and heat shock protein (HSP) 27 after binding of PV antibodies to cultured keratinocytes. In human keratinocyte cultures, inhibitors of p38MAPK prevented PV IgG-induced phosphorylation of HSP27 and, more importantly, prevented the early cytoskeletal changes associated with loss of cell-cell adhesion. This study was undertaken to (i) determine whether p38MAPK and HSP25, the murine HSP27 homolog, were similarly phosphorylated in an in vivo model of PV and (ii) investigate the potential therapeutic use of p38MAPK inhibition to block blister formation in an animal model of PV. We now report that p38MAPK inhibitors prevented PV blistering disease in vivo. Targeting the end-organ by inhibiting keratinocyte desmosome signaling may be effective for treating desmosome autoimmune blistering disorders.
Project description:Pemphigus vulgaris is perhaps the most formidable disease encountered by dermatologists. In the days before steroid therapy the mortality rate was 95 per cent, death occuring usually within 14 months. The cause of death was septicaemia, starvation and toxic state. Corticosteroid, immunosuppressants and adjuvant therapy have reduced the mortality to 10-40 per cent with the cause of death being uncontrolled pemphigus, complications of corticosteroid and immunosuppressant therapy, septicaemia and thromboembolism. Elderly patients and patients with extensive lesions have higher mortality rate. Prognosis has further improved by intensive care, adequate fluid replacement, nutritional support, a co-herent antibacterial policy alongwith aggressive corticosteroid therapy and immunosuppressants. Plasmapheresis has been used in patients who fail to respond to conventional management. Extracorporeal photophoresis has been reported to be effective in patients with 'treatment resistance' pemphigus vulgaris.
Project description:BackgroundPesticides, mainly organophosphates (OP), have been related to increased risk of pemphigus vulgaris (PV) and pemphigus foliaceus (PF), nevertheless, their measurement has not been determined in pemphigus patients.ObjectiveTo evaluate pesticide exposure and pesticide measurement, comparing PV, PF and control groups in Southeastern Brazil.MethodsInformation about urban or rural residency and exposure to pesticides at the onset of pemphigus was assessed by questionnaire interview; hair samples from the scalp of PV, PF, and controls were tested for OP and organochlorines (OC) by gas-phase chromatography coupled to mass spectrometry.ResultsThe minority of PV (2 [7.1%] of 28) and PF (7 [18%] of 39), but none of the 48 controls, informed living in rural areas at the onset of pemphigus (p = 0.2853). PV (33.3%), PF (38.5%), and controls (20%) informed exposure to pesticides (p = 0.186). Twenty-one (14.8%) of 142 individuals tested positive for OP and/or OC: PV (2 [6.3%] of 32) and PF (11 [25.6%] of 43) had similar pesticides contamination as controls (8 [11.9%] of 67) (p = 0.4928; p = 0.0753, respectively), but PF presented higher contamination than PV (p = 0.034). PV did not present any positivity for OP. Three (7%) PF tested positive for both OP and OC. Some PF tested positive for three or four OP, mainly diazinon and dichlorvos.Study limitationLack of data for some controls.ConclusionAlthough the frequency of PV and PF patients exposed to pesticides was similar, pesticides were more frequently detected in hair samples from PF compared to PV. The cause-effect relationship still needs to be determined.
Project description:In patients with pemphigus vulgaris (PV), autoantibodies against desmoglein 3 (Dsg3) cause loss of cell-cell adhesion of keratinocytes in the basal and immediate suprabasal layers of stratified squamous epithelia. The pathology, at least partially, may depend on protease release from keratinocytes, but might also result from antibodies interfering with an adhesion function of Dsg3. However, a direct role of desmogleins in cell adhesion has not been shown. To test whether Dsg3 mediates adhesion, we genetically engineered mice with a targeted disruption of the DSG3 gene. DSG3 -/- mice had no DSG3 mRNA by RNase protection assay and no Dsg3 protein by immunofluorescence (IF) and immunoblots. These mice were normal at birth, but by 8-10 d weighed less than DSG3 +/- or +/+ littermates, and at around day 18 were grossly runted. We speculated that oral lesions (typical in PV patients) might be inhibiting food intake, causing this runting. Indeed, oropharyngeal biopsies showed erosions with histology typical of PV, including suprabasilar acantholysis and "tombstoning" of basal cells. EM showed separation of desmosomes. Traumatized skin also had crusting and suprabasilar acantholysis. Runted mice showed hair loss at weaning. The runting and hair loss phenotype of DSG3 -/- mice is identical to that of a previously reported mouse mutant, balding (bal). Breeding indicated that bal is coallelic with the targeted mutation. We also showed that bal mice lack Dsg3 by IF, have typical PV oral lesions, and have a DSG3 gene mutation. These results demonstrate the critical importance of Dsg3 for adhesion in deep stratified squamous epithelia and suggest that pemphigus autoantibodies might interfere directly with such a function.
Project description:Pemphigus vulgaris (PV) is an autoimmune epidermal blistering disease caused by autoantibodies directed against the desmosomal cadherin desmoglein-3 (Dsg3). Significant advances in our understanding of pemphigus pathomechanisms have been derived from the generation of pathogenic monoclonal Dsg3 antibodies. However, conflicting models for pemphigus pathogenicity have arisen from studies using either polyclonal PV patient IgG or monoclonal Dsg3 antibodies. In the present study, the pathogenic mechanisms of polyclonal PV IgG and monoclonal Dsg3 antibodies were directly compared. Polyclonal PV IgG cause extensive clustering and endocytosis of keratinocyte cell surface Dsg3, whereas pathogenic mouse monoclonal antibodies compromise cell-cell adhesion strength without causing these alterations in Dsg3 trafficking. Furthermore, tyrosine kinase or p38 MAPK inhibition prevents loss of keratinocyte adhesion in response to polyclonal PV IgG. In contrast, disruption of adhesion by pathogenic monoclonal antibodies is not prevented by these inhibitors either in vitro or in human skin explants. Our results reveal that the pathogenic activity of polyclonal PV IgG can be attributed to p38 MAPK-dependent clustering and endocytosis of Dsg3, whereas pathogenic monoclonal Dsg3 antibodies can function independently of this pathway. These findings have important implications for understanding pemphigus pathophysiology, and for the design of pemphigus model systems and therapeutic interventions.
Project description:ObjectiveApoptotic events mediated by mitochondrial injury play an important role on the onset of Pemphigus vulgaris (PV). The thioredoxin-2 (Trx2)/apoptosis signal-regulating kinase 1 (ASK1) signaling pathway is considered a key cascade involved on the regulation of mitochondrial injury. Hence, we have investigated the regulatory mechanism of the Trx2/ASK1 signaling in PV-induced mitochondrial injury.MethodsSerum and tissue samples were collected from clinical PV patients to detect the oxidative stress factors, cell apoptosis, and expression of members from Trx2/ASK1 signaling. HaCaT cells were cultured with the serum of PV patients and transfected with Trx2 overexpression or silencing vector. Changes in the levels of reactive oxygen species (ROS), mitochondrial membrane potential (△ψm), and apoptosis were further evaluated. A PV mouse model was established and administered with Trx2-overexpressing plasmid. The effect of ectopic Trx2 expression towards acantholysis in PV mice was observed.ResultsA series of cellular and molecular effects, including (i) increased levels of oxidative stress products, (ii) destruction of epithelial cells in the skin tissues, (iii) induction of apoptosis in keratinocytes, (iv) reduction of Trx2 protein levels, and (v) enhanced phosphorylation of ASK1, were detected in PV patients. In vitro experiments confirmed that Trx2 can inhibit ASK1 phosphorylation, alleviate ROS release, decrease △ψm, and lower the apoptotic rate. Injection of Trx2-overexpressing vectors in vivo could also relieve acantholysis and blister formation in PV mice.ConclusionThe Trx2/ASK1 signaling pathway regulates the incidence of PV mediated by mitochondrial injury.