Occurrence of Bullous Pemphigoid in a Longstanding Case of Rheumatoid Arthritis in an Indian Patient: A Rare Association.

Bullous pemphigoid is a subepidermal blistering disease that rarely involves the mucous membranes and possesses circulating antibodies against BP antigen II (BP180) and BP antigen I (BP230). Rheumatoid arthritis (RA) is a progressive inflammatory autoimmune disease that is characterized by joint inflammation and systemic involvement. The co-occurrence of RA, which is likewise linked to autoimmunity, with bullous pemphigoid may not be merely coincidental. A 55-year-old female, a known case of RA for 25 years, presented to us with multiple pruritic vesiculobullous lesions. After a thorough clinical and laboratory assessment, she was diagnosed with bullous pemphigoid. This emphasizes the significance of the simultaneous occurrence of autoimmune disorders and the need for vigilant and timely identification.

Risk of bullous pemphigoid and pemphigus in patients on chronic dialysis: A nationwide population-based cohort study.

Bullous pemphigoid has a high incidence among dialysis patients. However, whether or not chronic dialysis is an independent risk factor of bullous pemphigoid remains unclear. We aimed to investigate the effect of chronic dialysis on the development of bullous pemphigoid and pemphigus. We performed a retrospective cohort study using records from Taiwan's National Health Insurance Research Database between 2008 and 2019. We identified a dialysis cohort that included patients on chronic hemodialysis and peritoneal dialysis, and the hazard ratios (HRs) for bullous pemphigoid and pemphigus were compared with those of a sex-, age-, and index-matched cohort, then the results were adjusted for various confounding factors. Among 93 538 patients on chronic dialysis and 93 538 patients in the control group, 287 and 139 developed incident bullous pemphigoid, and 45 and 35 developed incident pemphigus after a median follow-up of 3.7 and 5.6 years, respectively. The incidence rates of bullous pemphigoid in the dialysis patients and the control group were 74.2 and 25.2 per 100 000 person-years, respectively (difference between groups, P < 0.0001). The incidence rates of pemphigus in the dialysis patients and the control group were 11.6 and 6.3 per 100 000 person-years, respectively (difference between groups, P < 0.01). Cox proportional hazard adjustment showed the HR for bullous pemphigoid in dialysis patients was 2.12 (95% confidence interval [CI] 1.64-2.74, P < 0.0001) compared with the control group. Dialysis patients aged <75 years had an even higher risk of bullous pemphigoid development (5- to 8-fold) than the control group. The adjusted HR for pemphigus was not elevated in dialysis patients (adjusted HR 1.52, 95% CI 0.87-2.67, P = 0.14). Chronic dialysis is an independent risk factor for developing bullous pemphigoid, but not a risk factor for pemphigus. Physicians should be aware of the predisposition of chronic dialysis patients to bullous pemphigoid.

Pemphigus vulgaris and focal segmental glomerulosclerosis (FSGS): First reported case and a review of the literature.

Key Clinical Message: There may be a connection between pemphigus vulgaris and nephrotic syndrome, as evidenced by the occurrence of focal segmental glomerulosclerosis in our pemphigus vulgaris patient and reviewing relevant literature. Therefore, if a patient with pemphigus vulgaris presents with bilateral lower extremity edema or proteinuria detected during urinalysis, it could indicate involvement of the kidneys. Abstract: Pemphigus vulgaris is a type of autoimmune blistering disease characterized by the presence of IgG autoantibodies against desmogleins 3 and 1. It is important to evaluate potential autoimmune associations in patients with pemphigus vulgaris so that appropriate laboratory and physical examinations can be performed to monitor for any increased risk of other autoimmune disorders. This case report describes a 55-year-old woman who presented with oral and axillary erosions, which were diagnosed as pemphigus vulgaris based on skin histopathology and immunofluorescence. During follow-up, the patient was found to have proteinuria, which led to referral to a nephrologist. The patient was diagnosed with nephrotic syndrome and minimal change disease after a biopsy. Despite treatment, the patient's proteinuria persisted and serum creatinine levels increased, leading to a second biopsy which confirmed the diagnosis of focal segmental glomerulosclerosis. This study reports on the first case of pemphigus vulgaris with focal segmental glomerulosclerosis and reviews the literature on the co-occurrence of acquired immunobullous diseases and nephrotic syndrome of any kind.

Deciphering the Contribution of BP230 Autoantibodies in Bullous Pemphigoid.

Bullous pemphigoid (BP) is a subepidermal autoimmune blistering disease predominantly affecting elderly patients and carries significant morbidity and mortality. Patients typically suffer from severe itch with eczematous lesions, urticarial plaques, and/or tense blisters. BP is characterized by the presence of circulating autoantibodies against two components of the hemidesmosome, BP180 and BP230. The transmembrane BP180, also known as type XVII collagen or BPAG2, represents the primary pathogenic autoantigen in BP, whereas the intracellular BP230 autoantigen is thought to play a minor role in disease pathogenesis. Although experimental data exist suggesting that anti-BP230 antibodies are secondarily formed following initial tissue damage mediated by antibodies targeting extracellular antigenic regions of BP180, there is emerging evidence that anti-BP230 IgG autoantibodies alone directly contribute to tissue damage. It has been further claimed that a subset of patients has a milder variant of BP driven solely by anti-BP230 autoantibodies. Furthermore, the presence of anti-BP230 autoantibodies might correlate with distinct clinical features. This review summarizes the current understanding of the role of BP230 and anti-BP230 antibodies in BP pathogenesis.

Diagnostics for Dermatologic Diseases with Autoantibodies.

BACKGROUND: Dermatologic diseases with autoantibodies were recognized early as autoimmunity became accepted as a pathogenic immunologic concept. Laboratory testing to identify disease-defining autoantibodies and investigate their role in pathophysiology has evolved since. CONTENT: Blistering dermatologic diseases, profiled by autoantibody production, target epithelial components critical in cell-cell and cell-matrix adhesion, resulting in epithelial separation and other characteristic features of the disorders. This review covers the clinical indications for dermatologic disease-related autoantibody testing, the specifics of procuring specimens to test, the available diagnostic tests, and information provided by the testing. Atypical, uncharacteristic, and less well-known clinical and autoantibody profiles as well as several of the many future prospects for expansion of the testing applications are elaborated on in the online Data Supplement. SUMMARY: Autoantibody-associated dermatologic diseases are acquired immunologic disorders that have considerable clinical implications affecting essential barrier functions of skin and mucous membranes and causing discomfort, including pain and pruritus. Certain of the diseases can have life-threatening manifestations, and treatments can have significant side-effects. The skin diseases may presage other clinical associations that are important to recognize and treat. Laboratory testing aids in the diagnosis of these diseases through identification of the autoantibodies and is essential for prompt and precise knowledge of the disease type for prognosis, further clinical evaluations, and treatment decisions.

Impact of adding an IgG4 conjugate to routine direct immunofluorescence testing for subepithelial and intraepithelial autoimmune blistering disorders.

BACKGROUND: Certain autoimmune bullous dermatoses are mediated by autoantibodies of the IgG4 subclass. We determined the diagnostic impact of adding IgG4 to our conventional direct immunofluorescence (DIF) panel. METHODS: For all cases submitted to our referral laboratory for DIF over 1 month (n = 630), we performed IgG4 testing and collected consecutive biopsy specimens showing definite or indeterminate linear or cell-surface deposition of IgG, IgG4, and/or C3. On retrospective blinded review, we classified the pattern and whether the findings were definite, indeterminate, or negative. When present, substantial background staining was recorded. RESULTS: Seventy DIF specimens met the inclusion criteria. Of 22 (31.4%) specimens equivocal for linear or cell-surface deposition, 9 (40.9%) had definitive IgG4 findings, either linear (3 of 14 equivocal linear cases; 21.4%) or cell-surface (6 of 8 equivocal cell-surface cases; 75.0%). Background deposition was substantial in 14 cases (20.0%) for IgG but in none for C3 or IgG4. CONCLUSION: IgG4 allowed the classification of over 40% of DIF cases that were otherwise equivocal by IgG and C3. IgG4 staining showed lower levels of non-specific background staining than IgG or C3. IgG4 appears to contribute most value in cases with cell-surface deposition or with equivocal linear IgG deposition and negative C3 results.

Subunit-Specific Reactivity of Autoantibodies Against Laminin-332 Reveals Direct Inflammatory Mechanisms on Keratinocytes.

Laminin-332 pemphigoid is a rare and severe autoimmune blistering disease, caused by IgG autoantibodies targeting laminin-332 in the dermal-epidermal basement zone. Laminin-332 pemphigoid is characterized by variable inflammatory infiltrate and the predominance of non-complement-fixing antibodies. Given these findings, we hypothesized that IgG autoantibodies to laminin-332 directly resulted in keratinocyte expression of inflammatory factors. We performed RNA-seq on primary human keratinocytes treated with IgG from patients with laminin-332 pemphigoid. Genes for numerous cytokines and chemokines were upregulated, including CSF2, CSF3, CXCL1, CXCL5, CXCL3, CXCL8, CXCL10, CXCL1, IL6, IL7, IL15, IL23, IL32, IL37, TGFB2 as well as metalloproteases. Considering the pro-inflammatory and proteolytic effect of autoantibodies from patients with laminin-332 pemphigoid identified in our initial experiment, we next questioned whether the reactivity against specific laminin subunits dictates the inflammatory and proteolytic keratinocyte response. Then, we treated keratinocytes with IgG from a separate cohort of patients with reactivity against individual subunits of laminin-332. We identified upregulation of IL-1α, IL-6, IL-8, CXCL1, MMP9, TSLP, and GM-CSF at the protein level, most notably in keratinocytes treated with IgG from laminin ß3-reactive patients. We for the first time demonstrated a pro-inflammatory response, similar to that described in keratinocytes treated with IgG autoantibodies from patients with bullous pemphigoid, providing novel insight into the pathogenesis of laminin-332 pemphigoid and laminin-332 biology.

Neonatal pemphigoid gestationis: An atypical presentation of a rare disease.

Bullous pemphigoid (BP) is an autoimmune blistering disease characterized by urticarial plaques and/or vesicles and tense bullae. A unique presentation of BP can occur during pregnancy, the postpartum period after delivery, or with the initiation of contraception, in which case it is referred to as pemphigoid gestationis (PG). In rare instances, newborns born to mothers with PG may also present with blisters due to transplacental passage of maternal anti-bullous pemphigoid 180 (BP180) or 230 (BP230) immunoglobulin G (IgG). In this report, we present an unusual case of neonatal PG in an infant born to an asymptomatic mother without a previous diagnosis of PG.

A rare case of childhood mucous membrane pemphigoid involving the oral and genital mucosa.

Mucous membrane pemphigoid (MMP) is a rare chronic immunobullous disease that involves the mucous membranes and may result in significant scarring and complications if diagnosis is delayed. MMP typically occurs in elderly patients, with very few cases reported in children. Here, we present a 12-year-old female patient with childhood-onset oral and genital MMP, clinically suspected to be lichen sclerosus, but eventually diagnosed as MMP after multiple supportive biopsies and confirmatory direct immunofluorescence. Although treatment was challenging, the combined use of systemic corticosteroids, dapsone, and mycophenolate mofetil was ultimately successful in achieving disease control.

Systemic diseases and the cornea.

There is a number of systemic diseases affecting the cornea. These include endocrine disorders (diabetes, Graves' disease, Addison's disease, hyperparathyroidism), infections with viruses (SARS-CoV-2, herpes simplex, varicella zoster, HTLV-1, Epstein-Barr virus) and bacteria (tuberculosis, syphilis and Pseudomonas aeruginosa), autoimmune and inflammatory diseases (rheumatoid arthritis, Sjögren's syndrome, lupus erythematosus, gout, atopic and vernal keratoconjunctivitis, multiple sclerosis, granulomatosis with polyangiitis, sarcoidosis, Cogan's syndrome, immunobullous diseases), corneal deposit disorders (Wilson's disease, cystinosis, Fabry disease, Meretoja's syndrome, mucopolysaccharidosis, hyperlipoproteinemia), and genetic disorders (aniridia, Ehlers-Danlos syndromes, Marfan syndrome). Corneal manifestations often provide an insight to underlying systemic diseases and can act as the first indicator of an undiagnosed systemic condition. Routine eye exams can bring attention to potentially life-threatening illnesses. In this review, we provide a fairly detailed overview of the pathologic changes in the cornea described in various systemic diseases and also discuss underlying molecular mechanisms, as well as current and emerging treatments.

Pruritic annular and vesicular eruption on trunk and extremities.

We report a case of linear IgA bullous dermatosis, a rare autoimmune blistering disorder that usually presents with the abrupt onset of tense bullae. We also emphasize the importance of direct immunofluorescence for the definitive diagnosis.

Childhood ocular mucous membrane pemphigoid successfully treated with rituximab.

Ocular mucous membrane pemphigoid (MMP) is a chronic autoimmune blistering disease that usually affects elderly patients being extremely rare in pediatric population. Despite aggressive immunosuppressive therapy, ocular MMP may progress causing significant morbidity. Herein, we describe a toddler with ocular MMP successfully treated with rituximab.