Bullous Disorders Research Articles

Use of multivariant enzyme-linked immunosorbent assay (ELISA) in the diagnosis of autoimmune bullous disorders in a resource-limited setting: A single-center experience

Background Autoimmune blistering disorders (AIBD) result from the formation of auto-antibodies against adhesion proteins of the skin/mucosa(e). These auto-antibodies can be detected in the bound form in the tissue using direct immunofluorescence (DIF) or blood circulation using enzyme-linked immunosorbent assay (ELISA) or other methods. Objectives The objective of this study was to evaluate the concordance rate between the results of multivariant ELISA and the diagnosis of AIBD made using DIF and histopathology in an appropriate clinical context. Methods This was a retrospective study (December 2020 to April 2023) in which the multivariant ELISA assay (able to detect antibodies against desmoglein 1, desmoglein 3, BP180, BP230, envoplakin, and collagen VII) data were retrieved from the dermatology laboratory. Corresponding clinical and histopathology data were searched from relevant institutional databases. As per routine practice, the final diagnosis was assigned based on the clinical presentation, histopathology features and corresponding DIF report. Results After screening the records of 338 patients during the study period, 253 patients were included. Of them, 194 had AIBD and 59 had non-AIBD. In the autoimmune blistering disorder group, 122 and 72 patients had pemphigus and pemphigoid, respectively. Overall, a good level of agreement was found between multivariant ELISA results and the final diagnosis (Fleiss kappa = 0.631, p-value < 0.001). The pemphigus vulgaris group exhibited good agreement (kappa = 0.796, p < 0.001), while pemphigus foliaceous, bullous pemphigoid and non-autoimmune blistering disorders demonstrated moderate agreement (kappa = 0.641, 0.651, 0.533, respectively; p < 0.001). The mucous membrane pemphigoid group had a fair agreement (kappa = 0.289; p < 0.001). Limitations The limitations for the study were its retrospective design, fewer number of patients in certain groups like paraneoplastic pemphigus and gold-standard single antigen specific ELISA was not done. Conclusion Considering good agreement between the multivariant ELISA and the gold-standard diagnosis (clinical findings plus histopathology plus DIF), multivariant ELISA can be used for the diagnosis of AIBDs in places where facilities for DIF are unavailable. Multivariant ELISA can improve etiological diagnosis for a set of autoimmune blistering disorders whose target antigens are represented in the multivariant panel.

Direct immunofluorescence in bullous disorders: A mini-review

Background: Immunofluorescence microscopy is an invaluable tool for different lesions in dermatopathology. These lesions include bullous lesions, vasculitis, and connective tissue disorders/systemic lupus erythematosus. In this review, we take a look at bullous disorders. Some of these diagnoses are not possible on routine histopathology alone and require immunofluorescence for confirmation. Different diseases can be diagnosed according to the immunoglobulins/complements, sites of deposition (dermo-epidermal / intercellular spaces / dermal), and their patterns (linear, granular). Knowing the exact type of lesion can help guide treatment accordingly.

Bullous Pemphigoid Severity and Levels of Antibodies to BP180 and BP230

The correlation between serum levels of autoantibodies against bullous pemphigoid (BP) antigens 180 (BP180) and 230 (BP230) with BP disease severity is unclear. To investigate the correlation of anti-BP180 and anti-BP230 immunoglobulin G (IgG) antibody levels with BP disease severity. A search was performed of the Cochrane Central Register of Controlled Trials, Embase, and PubMed databases from their respective inception to April 11, 2024. Studies evaluating the correlation between serum levels of anti-BP180 or anti-BP230 IgG measured using enzyme-linked immunosorbent assay (ELISA) and disease severity assessed per the Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) or BP Disease Area Index (BPDAI) were included. No language or geographic restrictions were imposed. Nearly 0.4% of initially identified studies met the selection criteria. One researcher extracted data and another researcher confirmed data. The risk of bias was independently assessed by these researchers using the Quality Assessment of Diagnostic Accuracy Studies 2 tool, with discrepancies resolved by discussion with a third researcher. A random-effects model meta-analysis and a subgroup analysis were conducted based on the ELISA kit manufacturers. Pooled correlation coefficients of antibody levels with ABSIS and BPDAI. In all, 14 studies with 1226 participants were analyzed. The risk of bias of included studies was generally low. The meta-analysis found anti-BP180 autoantibody levels showed moderate correlation with objective BPDAI (r = 0.56; 95% CI, 0.46-0.64) at baseline, strong correlation (r = 0.63; 95% CI, 0.39-0.79) at 3-month follow-up, and moderate correlation (r = 0.53; 95% CI, 0.25-0.72) at 6-month follow-up. Anti-BP180 autoantibody levels also showed moderate correlation (r = 0.52; 95% CI, 0.39-0.62) with ABSIS at baseline, strong correlation (r = 0.62; 95% CI, 0.39-0.79) at 3-month follow-up, and moderate correlation (r = 0.53; 95% CI, 0.25-0.72) at 6-month follow-up. By contrast, anti-BP230 autoantibody levels showed no association with objective BPDAI and ABSIS at diagnosis and follow-up. The subgroup analysis found similar results when using different ELISA kits. The findings of this systematic review and meta-analysis indicated that anti-BP180 autoantibody levels may serve as an adjunctive tool for monitoring BP disease severity and guiding clinical care for patients with BP.

Epidermolysis Bullosa with Pyloric Atresia in a Premature Infant

Introduction: Epidermolysis bullosa with pyloric atresia (EB-PA) is a rare subtype of the broader bullous disorder known as epidermolysis bullosa resulting from mutations in basal keratinocyte proteins, most notably plectin or α6β4 integrin. Objective: Our case aims to highlight both the cutaneous and extracutaneous manifestations of this entity that lead to a diagnosis and guide management. Case: We report a case of EB-PA in a newborn born with skin fragility and respiratory distress, later found to have mutations in both PLEC genes on chromosome 8. In addition to forming bullae and erosions requiring diligent wound care, she developed pyloric atresia and hypoxia from respiratory secretions necessitating a pyloromyotomy and proximal duodenal resection, tracheostomy tube, gastrostomy tube, and antibiotics for intermittent sepsis. Conclusion: EB-PA is characterized by instability in all plectin-containing tissues, particularly the skin, but the prevalence of plectin throughout the body can lead to wide-ranging and serious complications, including gastrointestinal and tracheoesophageal strictures, protein-losing enteropathy, and renal anomalies. EB is readily recognizable clinically when presenting with classic bullae but given the serious nature of the extracutaneous manifestations of EB-PA, prompt diagnosis with genetic testing and surveillance for systemic involvement is essential to promote comfort and survival in this potentially fatal neonatal disease.

Autoimmune Sequelae After Delta or Omicron Variant SARS-CoV-2 Infection in a Highly Vaccinated Cohort

Studies have reported increased risk of autoimmune sequelae after SARS-CoV-2 infection. However, risk may potentially be attenuated by milder Omicron (B.1.1.529) variant infection and availability of booster vaccination. To estimate the 300-day risk of new-incident autoimmune sequelae after SARS-CoV-2 Delta or Omicron BA.1 or BA.2 variant infection in adults who received COVID-19 vaccines and boosters, compared with a contemporary control group without infection. This cohort study in Singapore enrolled adults from September 1, 2021, to March 7, 2022, and followed up for 300 days. Participants were adults aged 18 years or older with SARS-CoV-2 infection during the predominance of the Delta and Omicron BA.1 or BA.2 variants and were still alive at 30 days after COVID-19 diagnosis. The national SARS-CoV-2 testing registry was used to construct cohorts of adults with SARS-CoV-2 Delta or Omicron BA.1 or BA.2 variant infection (hereafter, cases) and a contemporaneous group with negative polymerase chain reaction or rapid antigen test results (hereafter, controls). New-incident autoimmune diagnoses after SARS-CoV-2 infection. This information was recorded in the MediClaims national health care claims database and identified 31 to 300 days after index date of infection. Risks and excess burdens were estimated using Cox proportional hazards regression model with overlap weights applied. In total, 1 766 036 adults (915 096 females [51.9%]; mean [SD] age, 49 [18] years) were included in the study population, with 480 082 (27.2%) categorized as cases and 1 285 954 (72.8%) as controls. Of these adults, 73.1% had Chinese, 13.7% Malay, and 9.9% Indian ethnicity. There were 104 179 cases and 666 575 controls included during the Delta variant-predominance transmission, while 375 903 cases and 619 379 controls were included during the Omicron variant-predominance transmission. During the Delta variant period, 81.1% of cases had completed primary vaccination; during the Omicron variant period, 74.6% of cases received boosters. No significantly elevated risk of 12 prespecified autoimmune sequelae was recorded across the Omicron and Delta variant cohorts. Elevated risks of inflammatory bowel disease (adjusted hazard ratio [AHR], 2.23; 95% CI, 1.45-3.46; P < .001) and bullous skin disorders (AHR, 4.88; 95% CI, 2.47-9.66; P < .001) were observed only in the subset of COVID-19 cases requiring hospitalization during the predominance of the Omicron variant. While elevated risk of vasculitis (AHR, 5.74; 95% CI, 1.48-22.23; P = .01) was observed in vaccine-breakthrough Omicron variant infections, no increased risk of vasculitis was observed in the corresponding subgroup who received boosters. This cohort study observed no significantly elevated long-term risk of autoimmune sequelae after SARS-CoV-2 Delta and Omicron BA.1 or BA.2 variant infection, except for a modestly increased risk of inflammatory bowel disease and bullous skin disorders in the hospitalized subgroup during the predominance of the Omicron variant. Booster vaccination appeared to mitigate the risk of long-term autoimmune sequelae.

Trends in disease severity and quality of life outcome measures in pemphigus clinical trials: A scoping review.

Pemphigus represents a spectrum of autoimmune-mediated blistering diseases associated with high morbidity, mortality and reduced quality of life (QoL). Despite an increase in pemphigus clinical trials, the varied instrument measurements of disease severity and QoL outcomes make comparisons between studies challenging. This study aimed to evaluate trends in the use of disease severity and QoL outcome measurements in pemphigus clinical trials. A review of pemphigus clinical trials was conducted using the PubMed,Embase, Cochrane Reviews and ClinicalTrials.gov databases up until September 2023. Only pemphigus randomized clinical trials that assessed at least one disease severity and/or QoL outcome were included. Overall, 53 clinical trials were eligible for this review. All clinical trials evaluated a disease severity outcome, with the Pemphigus Disease Area Index being the most used validated questionnaire (28.3% of trials) and more popular after 2015 (47.8% of trials since). The autoimmune bullous skin disorder intensity score (7.6%) and visual analogue measurements (7.6%) have fallen out of favour. Most studies now include lab parameters (56.5% of trials after 2015), with anti-desmoglein 1 and 3 antibody levels (30.2%), immunoglobulins (IgG and/or IgM and IgA) (11.3%), and anti-drug antibody levels (7.6%) being frequently evaluated. A small portion of trials evaluated QoL (26.5% of studies), with the autoimmune bullous quality of life being the most common (15.1%), however QoL utilization as an outcome measure has been increasing since 2015 (61.1% of trials since). Standardising the use of validated outcome measurements allows for better data interpretation, comparability and clinical application of results.

Case series of cutaneous myiasis in neglected cases of autoimmune bullous disorders.

Myiasis is an infestation of the tissues and organs of living vertebrates and humans by fly larvae, usually those belonging to the Calliphoridae family. The larvae feed on the host's necrotic or living tissue. Preexisting dermatological conditions and poor hygiene have been described as predisposing factors for myiasis, and it is especially common among neglected, dependent patients. Based on our literature search, we could find only a few case reports reported on cutaneous myiasis in autoimmune bullous disorders. It is especially more common in the South Indian Tamil Nadu population due to the false belief that autoimmune blistering disorders like pemphigus and bullous pemphigoid are considered chicken pox and treated with neem and turmeric preparation with poor hygiene. Herein we report a series of eight autoimmune blistering disorders with cutaneous myiasis.

Pemphigus oral lesions area index (POLAI): A new scoring scale for assessing oral pemphigus vulgaris

AbstractObjectivesCurrent scales for Pemphigus vulgaris (PV) do not adequately represent the clinical variability of oral lesions. This study aimed to develop an independent scale, the Pemphigus Oral Lesions Area Index (POLAI), for assessment of oral PV exclusively, and compare POLAI, Pemphigus Disease Area Index (PDAI), Autoimmune Bullous Skin Disorder Intensity Score (ABSIS) and Oral Disease Severity Score (ODSS) regarding inter‐ and intra‐observer reliability and validity.Materials and MethodsRetrospective cohort included 209 sets of digital‐photographs. Additional clinical cohort included 32 PV patients. All visits were assessed by four clinicians using the PDAI, ABSIS, ODSS and POLAI, and were rated by three specialists using the Physician's Global Assessment (PGA).ResultsThe intraclass correlation coefficient showed the inter‐observer reliability with 0.89 and 0.86 for PDAI, 0.87 for ABSIS, 0.93 for ODSS, 0.96 for POLAI, and 0.97 and 0.96 for PGA. Intra‐observer agreements showed excellent reliability for all 4 scores. Highest correlation was observed between PGA and POLAI (correlation coefficients were 0.96). The mean time taken to complete each scale was within 1.5 min.ConclusionPOLAI is valid for the assessment of oral PV with superior inter‐ and intra‐observer reliability to PDAI, ABSIS and ODSS, and is feasible in clinic.

Targeted serum proteome profiling reveals nicotinamide adenine dinucleotide phosphate (NADPH)-related biomarkers to discriminate linear IgA bullous disorder from dermatitis herpetiformis

Linear IgA bullous dermatosis (LABD) and dermatitis herpetiformis (DH) represent the major subtypes of IgA mediated autoimmune bullous disorders. We sought to understand the disease etiology by using serum proteomics. We assessed 92 organ damage biomarkers in LABD, DH, and healthy controls using the Olink high-throughput proteomics. The positive proteomic serum biomarkers were used to correlate with clinical features and HLA type. Targeted proteomic analysis of IgA deposition bullous disorders vs. controls showed elevated biomarkers. Further clustering and enrichment analyses identified distinct clusters between LABD and DH, highlighting the involvement of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Comparative analysis revealed biomarkers with distinction between LABD and DH and validated in the skin lesion. Finally, qualitative correlation analysis with DEPs suggested six biomarkers (NBN, NCF2, CAPG, FES, BID, and PXN) have better prognosis in DH patients. These findings provide potential biomarkers to differentiate the disease subtype of IgA deposition bullous disease.

Nail changes in pemphigus: a systematic review and meta-analysis.

Pemphigus is a group of autoimmune mucocutaneous bullous disorders characterized by acantholysis resulting from autoantibodies targeting epithelial cell surface antigens. Studies reflect the presence of nail manifestations in some patients and suggest a potential correlation with clinical severity. This study examines the overall prevalence and characterizes the diverse manifestations of nail changes in pemphigus. We searched Cochrane, MEDLINE, EMBASE, and LILACS from 1990 to June 26, 2023 for studies reporting different nail changes in pemphigus patients. Data were collected and pooled to obtain proportions of the prevalence of nail changes in patients with pemphigus and subgroup analysis for pemphigus foliaceous and pemphigus vulgaris. The risk of bias was assessed with the Joanna Briggs Institute Checklist. Of 321 studies screened, 14 studies with 1,208 patients were included. Paronychia (n = 185) and Beau's lines (n = 104) were the most common nail changes identified. The pooled prevalence of nail disease in pemphigus patients was 0.389 (number of studies; [95% CI]: n = 9; [0.160-0.680], with high heterogeneity between studies (I2 = 95.0%, P < 0.001). Subgroup analysis revealed the highest prevalence in pemphigus foliaceous at 0.342 (n = 3; [0.109-0.688]) and pemphigus vulgaris at 0.396 (n = 5; [0.114-0.769]). Nail changes exhibited varied temporal relationships with disease onset and flares, preceding, concurrent, or following these events. Correlation with disease severity was noted, although discrepancies between studies were reported. Nail changes in pemphigus, particularly pemphigus vulgaris and pemphigus foliaceous, may be underrecognized. Observations regarding temporal associations and potential correlations with disease severity highlight the diagnostic and prognostic implications of nail changes in pemphigus. The limitations of this study include study heterogeneity and possible bias. Further research to establish the correlation of the presence and severity of nail changes on the overall disease course would be helpful.

Current Knowledge on Nail Involvement in Autoimmune Bullous Disorders.

There are few studies, mainly case reports, on the involvement of the nail unit in autoimmune bullous disorders. Nail involvement in autoimmune bullous disorders is a significant clinical phenomenon, marked by a range of manifestations, most often not presenting with blisters like on the skin but rather with alterations of the nail unit such as paronychia, onychomadesis, or onycholysis. This involvement is particularly notable due to the unique immunological features of the nail unit, including the expression of various antigens and the presence of Langerhans cells. Conditions like pemphigus vulgaris, bullous pemphigoid, epidermolysis bullosa acquisita, linear IgA disease, and bullous systemic lupus erythematosus can lead to nail abnormalities. The prevalence of nail manifestations varies according to the disorder, and diagnosis often relies on histopathological and immunofluorescence testing. Nail involvement correlates with disease severity and duration, sometimes serving as a herald sign. Further research is needed to guide therapeutic approaches for nail involvement in autoimmune bullous diseases. Nail involvement in autoimmune bullous nail disorders may be confusing as there are almost never bullae. One should keep the diagnosis in mind when facing an atypical paronychia.

Atypical Presentation of Infantile Bullous Pemphigoid with Isolated C3 Deposits

Bullous pemphigoid is an acquired autoimmune bullous disorder with autoantibodies targeting distinctive antigenic components of the skin and mucous membrane. It occurs mostly in the elderly, with the incidence of disease increasing with age and rare in children and infants. The clinical features are extremely polymorphous characterized by tense blisters and intense itching. The disease in pediatric population usually has a favorable outcome with appropriate treatment. Here, we present a case of infantile bullous pemphigoid with a rare presentation, triggered by vaccination and showing only linear C3 deposits.

A Case of Herpes Zoster Simulating Pemphigus Vulgaris Flare

Pemphigus vulgaris is an autoimmune bullous disorder caused by autoantibodies directed against desmogleins. There is an increased risk for developing herpes zoster in pemphigus vulgaris due to the prolonged and high doses immunosuppressant therapy. Here, we present a 52-year-old female patient with extensive pemphigus vulgaris who developed herpes zoster while on treatment which resulted in a diagnostic confusion and a Tzanck smear acted as a lifesaver revealing both multinucleated giant cells and acantholytic cells. Hence, a prompt decision of reducing the immunosuppressant and initiation of IV acyclovir helped the patient to recover faster. This case highlights the relevance of simple bedside investigation like Tzanck smear and reminds the clinician once again to be open to all possibilities.

The Effect of Vitamin D Supplementation on Autoimmune Bullous Skin Disorder Intensity Score on Bullous Pemphigoid and Acute Kidney Injury: A Case Report

Introduction: Bullous pemphigoid is the most common bullous-type autoimmune disease. Hypovitaminosis D is often associated with autoimmune disease and found in 86,7% bullous pemphigoid patients. Vitamin D supplementation in bullous pemphigoid patients ought to ameliorate its clinical symptoms.&#x0D; Case presentation: A-58 years old male patient with bullous pemphigoid and acute kidney injury admitted with a chief complaint of infected blisters all over the body. The patient had been treated for 1 week with worsening swallowing pain and low intake. On the 12th day of hospitalization, the patient was given calcitriol supplementation of 0,25 mcg per day. There was an improvement in clinical symptoms shown on autoimmune bullous skin disorder intensity score (ABSIS) from 57 on inpatient day 7 to 17.5 on inpatient day 20. Patient discharged on the 20th day of hospitalization with no emerging blisters and the ability to swallow minced food by mouth.&#x0D; Conclusion: Calcitriol supplementation of 0,25 mcg per day for 10 days helps to improve the ABSIS score in bullous pemphigoid patient with acute kidney injury. Administration of calcitriol is considered safe and well tolerated.

Evaluation of the Status of Patients with Autoimmune Bullous Diseases (Pemphigus and Bullous Pemphigoids) in Dermatology Clinics of Mashhad University of Medical Sciences During the COVID-19 Pandemic Using Telemedicine.

Background: The COVID-19 pandemic impacted the growth of telemedicine. The challenge was in the way of dermatologists, who needed a comprehensive examination of the lesions. Here, we tried a tele-management of patients with autoimmune bullous diseases. Methods: This cross-sectional study was conducted on confirmed bullous disorder cases. Demographic data and the status of COVID-19 infection were assessed in the patients. Some of the cases were provided online, and some with office visits. Drug and treatment plan changes were compared between these two groups. All statistical analysis was conducted using SPSS version 20. Result: Totally, 100 patients, including 46 males (46.0%) and 54 females (54.0%), 48.15 ± 11.11 years old, were studied. Among them, 73 were pemphigus vulgaris (73.0%), 11 were bullous pemphigoid (11.0%), 10 were pemphigus foliaceus (10.0%), and the other 6 (6.0%) were categorized as other autoimmune bullous diseases. During the pandemic, 38 cases (38.0%) had COVID-19 infection. 72 patients had office and 28 had online visits. Treatment plans after visits during the pandemic (p = 0.588) and drug dose change (p = 0.297) showed no significant difference between office and online visits. Conclusion: Our patients tended to plan office visits more than online; however, we found no differences regarding the plan or treatment changes. Online visit has good efficacy, but further investigation in case of provision of a suitable platform and getting the attention of the patients is needed.

Direct immunofluorescence (DIF) versus immunohistochemical (IHC) staining of complements and immunoglobulins (Ig) in pemphigus group.

Pemphigus is a group of bullous disorders of the skin characterized by the formation of autoantibodies present in the intercellular junction of the epidermis. Diagnosis is made by clinical, histopathological examination, and DIF. As DIF needs frozen sections, fluorescent tagged antibodies, UV light microscope for examination, and trained personnel, its non-availability makes a definitive diagnosis challenging. To evaluate the utility of IHC staining of complements and Ig in cases of Pemphigus. Twenty-six diagnosed cases of Pemphigus were stained by Peroxidase immunohistochemical method using monoclonal antibody to IgG, IgA, IgM, IgG4, C3, C4 d with DAB as chromogen. Pemphigus cases include twenty of pemphigus vulgaris (PV), four cases of pemphigus foliaceous (PF), and two of pemphigus vegetans (Pveg). Positivity was defined as the deposition of Ig and complements as distinct, continuous brown staining of keratinocytes at intercellular junctions. On IHC total of 20 PV 17 showed positivity (85%) for IgG, 11 (55%) C4d, 19 (95%) C3d, and 16 (80%) IgG4 deposits at the intercellular junction of the epidermis. All cases of PF showed a deposit of IgG, with three (75%) cases for IgG4, C3d, and C4d. Both cases of Pveg showed positivity for IgG and C4d while one case was negative for IgG4 and C3d. The overall IgG, C3, IgG4, and C4d expression for pemphigus was seen in 88%, 88%, 76.9%, and 61.5% of cases. The relation between these markers, combination of IgG and C3, was best related to each other ( P value = 0.80). The sensitivities for IgG, IgG4, and C3 were 77.8%%, 73%, and 73% resp. We conclude that IHC is a useful tool in the diagnosis of PV with the highest sensitivity of IgG and C3d. The combination of IgG and C3d could replace the DIF in almost all of our cases, so IHC on FFPE sections be used as an alternative method to DIF.

Diffuse Cutaneous Mastocytosis: A Current Understanding of a Rare Disease.

Mastocytosis is a heterogeneous disease characterized by the expansion and accumulation of neoplastic mast cells in various tissues. Diffuse cutaneous mastocytosis (DCM) is a rare and most severe form of cutaneous mastocytosis, which typically occurs in childhood. There have been reports of a familial DCM with specific gene mutations, indicating both sporadic and hereditary factors involved in its pathogenesis. DCM is associated with severe MC mediator-related symptoms and an increased risk of anaphylaxis. The diagnosis is based on the appearance of skin lesions, which typically show generalized thickening, erythroderma, blistering dermographism, and a positive Darier's sign. Recognition, particularly in infants, is challenging due to DCMs resemblance to other bullous skin disorders. Therefore, in unclear cases, a skin biopsy is crucial. Treatment focuses on symptom management, mainly including antihistamines and mast cell stabilizers. In extremely severe cases, systemic steroids, tyrosine kinase inhibitors, phototherapy, or omalizumab may be considered. Patients should be equipped with an adrenaline autoinjector. Herein, we conducted a comprehensive review of literature data on DCM since 1962, which could help to better understand both the management and prognosis of DCM, which depends on the severity of skin lesions, intensity of mediator-related symptoms, presence of anaphylaxis, and treatment response.

Patterns of Periodic Acid–Schiff Staining in Subepidermal Bullous Disorders with Emphasis on Bullous Pemphigoid

Abstract Background: Direct immunofluorescence (DIF) including salt split skin technique is quintessential in the diagnosis of subepidermal bullous disorders. These techniques are expensive and require technical expertise, limiting their diagnostic utility. The property of periodic-acid–Schiff to stain the basement membrane and the patterns produced by it was observed in a cohort of subepidermal bullous disorders, to see if it offers an alternative cost-effective testing method. Materials and Methods: This was a retrospective, observational study conducted in the department of general pathology, in a tertiary care medical center, over a period of 4 years. Only those cases for which paraffin sections, DIF and direct salt split skin immunofluorescence technique were available were included. The levels of anti-bullous pemphigoid (BP) antibodies were collected where available. Results: Of the 21 cases analyzed, 15 were BP, two each of epidermolysis bullosa acquisita (EBA) and lichen planus pemphigoides (LPP), one each of porphyria cutanea tarda (PCT), and bullous systemic lupus erythematosus (SLE). All the cases of BP, LPP and EBA showed a floor pattern of staining with periodic acid–Schiff (PAS) stain. Roof pattern of staining was observed in bullous SLE and PCT. PAS was found to be useful in diagnosing BP, especially in conjunction with an eosinophil rich bulla and anti-BP antibodies. Conclusion: We found that PAS stain could be an adjunct to hematoxylin and eosin stain when the diagnosis of BP is in doubt. However, larger sample size is needed to study its utility in other subepidermal bullous disorders.

A-270 - Autoimmune Bullous Disorders induced by Cyclin-Dependent Kinase 4/6 inhibitors – first case series from the EADV Task Force “Dermatology for Cancer Patients”

A-270 - Autoimmune Bullous Disorders induced by Cyclin-Dependent Kinase 4/6 inhibitors – first case series from the EADV Task Force “Dermatology for Cancer Patients”

Claudin-4 Upregulation in Acantholytic and Autoimmune-Mediated Bullous Disorders.

Claudin-4 is a key component of tight junctions, which play an important role in the formation of the epidermal barrier by forming a circumferential network in the granular layer that serves as a gatekeeper of the paracellular pathway. The aim of this study is to illustrate claudin-4 immunohistochemical staining patterns of different blistering disorders. We collected 35 cases, including two Hailey-Hailey disease, one Darier disease, three Grover disease, one acantholytic acanthoma, two warty dyskeratoma, 11 pemphigus vulgaris (PV) including six mucosal PV, and two pemphigus foliaceus. For comparison, we included five cases of normal skin, five eczema, and three bullous pemphigoid cases. Claudin-4 demonstrated weak-to-moderate expression in keratinocytes located in the stratum granulosum, keratinocytes surrounding hair follicles, and adnexal glands. Further, claudin-4 exhibited moderate-to-strong membranous staining in disrupted keratinocytes surrounding and within the acantholytic and bullous areas in 16/22 of the acantholytic cases (not seen in the six cases of mucosal PV) and all three bullous pemphigoids. This finding suggests that claudin-4 is upregulated in these conditions, which may be a compensatory response to the disrupted barrier function. This finding could shed light on the molecular mechanisms underlying disrupted barrier function in blistering disorders, independent of the specific underlying disease mechanism.