The role of T lymphocytes and cytokines in the pathogenesis of pemphigoid gestationis

Autoimmune bullous diseases in pregnancy: an overview of pathogenesis, clinical presentations, diagnostics and available therapies

Autoimmune bullous diseases (AIBDs) are rare organ-specific diseases characterized by the appearance of blisters and erosions on the skin and mucous membranes. These dermatoses are marked by the development of autoantibodies targeting the autoantigens located in intercellular junctions, i.e., between keratinocytes or in the basement membrane area. Therefore, the fundamental division of AIBDs into the pemphigus and pemphigoid groups exists. Although AIBDs are uncommon in the general population, their overall incidence is somewhat higher in women of all ages, for which a pregnant women can be likely affected too. While the pemphigoid gestationis is exclusive bullous dermatosis of pregnancy, the other AIBDs can also start or worsen during this period. The appearance of AIBDs in childbearing women is a particularly sensitive situation requiring exceptional clinicians' caution due to the possibility of pregnancy complications with adverse effects and risks to the mother and the child. Also, there are numerous management difficulties in the period of pregnancy and lactation related to the drugs' choice and safety. This paper aimed to outline the pathophysiologic mechanisms, clinical manifestations, diagnostic approach and therapy of the most commonly recognized AIBDs in pregnancy.

Current and Innovated Managements for Autoimmune Bullous Skin Disorders: An Overview

Autoimmune bullous skin disorders are a group of disorders characterized by the formation of numerous blisters and erosions on the skin and/or the mucosal membrane, arising from autoantibodies against the intercellular adhesion molecules and the structural proteins. They can be classified into intraepithelial or subepithelial autoimmune bullous dermatoses based on the location of the targeted antigens. These dermatoses are extremely debilitating and fatal in certain cases, depending on the degree of cutaneous and mucosal involvement. Effective treatments should be implemented promptly. Glucocorticoids serve as the first-line approach due to their rapid onset of therapeutic effects and remission of the acute phase. Nonetheless, long-term applications may lead to major adverse effects that outweigh the benefits. Hence, other adjuvant therapies are mandatory to minimize the potential harm and ameliorate the quality of life. Herein, we summarize the current therapeutic strategies and introduce promising therapies for intractable autoimmune bullous diseases.

Specific dermatoses of pregnancy other than pemphigoid gestationis

Specific dermatoses of pregnancy are skin disorders that occur specifically during or immediately after pregnancy and cannot be found in non-pregnant patients. According to the current consensus, they include atopic eruption of pregnancy (AEP), polymorphic eruption of pregnancy (PEP), pemphigoid gestationis (PG), and intrahepatic cholestasis of pregnancy (ICP). The diagnosis of specific dermatoses of pregnancy can be challenging due to their variation in clinical presentation; moreover, the tests currently available do not always provide the clue for the diagnosis. However, some distinctive features may be helpful to differentiate between such entities. Accordingly, the knowledge of specific dermatoses of pregnancy and of their management is critical, since their early recognition may allow to provide care for the mother and prevent potential increased fetal risk. In fact, while AEP and PEP do not affect maternal and fetal prognosis, PG and, mainly, ICP are associated to maternal complications as well as the risk of fetal loss. In this paper, the epidemiology, pathogenesis, clinical features as well as management of AEP and PEP are reviewed in detail, while PG is described in another article of this issue. Moreover, the main features of ICP, which cannot be considered a primarily skin disease but may be managed first by dermatologists, are reported.

Eosinophils as putative therapeutic targets in bullous pemphigoid

Bullous pemphigoid (BP) is the most common autoimmune subepidermal blistering skin disease and is characterized by the presence of autoantibodies directed against the hemidesmosomal proteins BP180 and BP230 that can be detected in the skin and serum of BP patients. Histologically, the dermal infiltration of eosinophils is obvious. The objective of this review was to present evidence that eosinophils play a key role in the pathogenesis of BP. Eosinophils, together with cytokines and chemokines regulating their production, recruitment and activation, are abundantly present in lesional skin, in blisters and in peripheral blood of patients with BP. Recently, using a cryosection model, eosinophils were demonstrated to induce dermal-epidermal separation in the presence of BP antibodies. Thus, eosinophils and their products, as well as mediators regulating their function, present promising targets for the treatment of BP.

A role for auto-immunity in chronic rhinosinusitis? Lessons learned from sub-epidermal bullous disorders of the skin

Chronic rhinosinusitis (CRS) is a frequent chronic condition, which has origins in complex interactions between genetic, immunological and microbial factors. The role of auto-immunity in CRS remains unclear, although recent studies have started to emerge in CRS patient refractory to maximal medical management. We discuss the possible auto-immunity link between CRS and other skin diseases, in particular acquired bullous dermatoses, and review the current evidence. We raise additional considerations for auto-immunity from both research and clinical standpoints.

Retrospective analysis of pemphigoid gestationis in 32 Saudi patients - Clinicopathological features and a literature review

BACKGROUND AND OBJECTIVES

Pemphigoid gestationis (PG) is a rare autoimmune-mediated blistering disease that mainly affects pregnant women in their 2nd or 3rd trimester and immediate postpartum period. In addition to the clinical assessment, the diagnosis of PG is usually confirmed by histological and immunological studies. PG usually flares up at the time of delivery and spontaneously improves postpartum. Prompt recognition and appropriate management may reduce morbidity associated with this disorder. This study aimed to determine the clinical, histopathological features and treatment of PG of Saudi patients.

MATERIALS AND METHODS

A retrospective study of 32 patients with pemphigoid gestationis (PG) was conducted from 1990 to 2014 at King Khalid University Hospital and Derma Medical Center, Riyadh, Saudi Arabia. Data regarding epidemiology, medical histories, clinical course, diagnostic test results and management were collected and analyzed.

RESULTS

A total of 32 patients with PG were analyzed. The mean age was 31.9 years. Seventy-four percent of the patients were multigravidas, and 2 patients were primigravidas. One hundred percent of the cases were singleton pregnancies. Eighty-four percent of the cases had the onset of PG during the 2nd and 3rd trimesters. One hundred percent of patients complained of pruritus, and 94% reported this as the first symptom. Erythematous plaques and vesiculobullous eruption were the most common skin presentation. The primary sites of involvement were the abdomen, trunk, lower (mainly thighs) and upper limbs. The face and mucus membranes were rarely involved. Fifty percent of patients had recurrent symptoms with their next pregnancy. Direct immunofluorescence revealed a linear deposition of the third component of the complement along the basement membrane zone in all cases (C3),while most of the cases showed positive linear deposition of IgG. Seventy five percent of our patients had a good response to oral corticosteroids, and only one patient needed IVIG. The vast majority of the patients (61%) became free of symptoms within 1-2 months of treatment. In 53% of the patients, maternal and fetal outcomes were good with no complications. Six pregnancies were complicated by preterm labor, 2 experienced IUGR (intrauterine growth restriction), and 2 had an abortion or stillbirth.

CONCLUSION

Our study does not differ dramatically when comparing the onset of PG, the high frequency of multigravida women, the clinical course and good patient outcomes but we observed that the first attack extended from primigravida to 11th pregnancy and slight increase in recurrence rate. Finally the timely diagnosis and appropriate management of PG may improve both maternal and neonatal outcome.

Mycophenolate mofetil as a treatment for urticarial dermatitis

We report two cases of adults with urticarial dermatitis who could not be managed by a variety of treatments but who obtained good control with mycophenolate mofetil (MMF). A clinical response was seen 6-8 weeks from treatment onset and they were maintained on MMF 1 g twice daily (case 1), and MMF 1 g omni mane and 500 mg omni nocte (case 2), with no major exacerbations for many years. MMF is an immunosuppressive agent, which is currently used off-label for many dermatological conditions. To date, there have been no studies investigating the use of MMF as a treatment for urticarial dermatitis. The cases we present suggest that MMF is an effective treatment for this condition, and we recommend that MMF be considered as a treatment option.

Postpartum pemphigoid gestationis

Pemphigoid gestationis (PG) or herpes gestationis is a rare autoimmune subepidermal blistering disorder associated with pregnancy. The condition typically develops during the second or third trimester of pregnancy, but has been rarely reported in the first trimester and postpartum period. Here, we report a case of PG that presented for the first time in the postpartum period, associated with a low birth weight baby.

Skin barrier disruption: a requirement for allergen sensitization?

For at least half a century, noninvasive techniques have been available to quantify skin barrier function, and these have shown that a number of human skin conditions and disorders are associated with defects in skin permeability. In the past decade, several genes responsible for skin barrier defects observed in both monogenetic and complex polygenic disorders have been elucidated and functionally characterized. This has led to an explosion of work in the past 6 years that has identified pathways connecting epidermal barrier disruption and antigen uptake, as well as the quality and/or magnitude of the antigen-specific adaptive immune response. This review will introduce the notion that diseases arise from the dynamic crosstalk that occurs between skin barrier and the immune system using atopic dermatitis or eczema as the disease prototype. Nevertheless, the concepts put forth are highly relevant to a number of antigen-driven disorders for which skin barrier is at least transiently compromised, such as psoriasis, allergic contact dermatitis, and blistering disorders.

[Pemphigoid gestationis: a review]

BACKGROUND

Pemphigoid gestationis (PG) is a rare auto-immune bullous disease occurring in one pregnant woman over 20,000 to 50,000.

OBJECTIVE

Review of literature about physiopathology, immunological diagnosis and treatment of PG.

METHODS

Research on Medline and Embase database without any time limit until April 2010. Because of the lack of randomized therapeutic trials in PG, retrospective series and case reports have been analyzed.

RESULTS

PG is due to auto-antibodies directed against BP180 secondary to a mother-fetus immunological tolerance breaking. Blister formation results from a complex mechanism involving TH2 lymphocytes, cytokines and polymorphonuclear cells. Clinically, the disease is characterized by a pruritic, more or less extensive erythemato-papulous eruption. The presence of vesicles and/or blisters is inconstant but evocative. Recovery occurs generally in a few weeks after delivery but relapses are frequent in subsequent pregnancies. Combined oral contraception may also trigger flares of the disease. Diagnosis is confirmed by direct immunofluorescence showing linear C3±IgG deposits in the dermal-epidermal junction. ELISA BP180-NC16A method is very sensitive to detect circulating auto-antibodies. Fetal prognosis is good, but early onset in 1(st) or 2(nd) trimester and blister formation are risk factors for prematurity and low birth weight. Rarely the newborn may be affected by very transitory blisters. Efficiency of very potent topical corticosteroids has been showed in several studies, and they may be used as first-intent treatment in moderate forms of PG. Systemic corticosteroids are indicated in extensive forms. In very exceptional chronic or relapsing PG, immunosuppressant agents may be necessary.

CONCLUSION

In the absence of consensus between moderate and severe forms of the disease, precise modalities of the steroid treatment (topical or systemic, duration and rhythm of decrease) are not well defined.

Immunohistological analysis of immune cells in blistering skin lesions

BACKGROUND

Bullous skin lesions are characterised by the presence of intraepidermal or subepidermal bullae. Although inflammatory cell infiltrate is a constant feature in these lesions, their immunophenotypic characterisation is still incomplete.

AIM

To determine whether the development of bullous skin diseases is associated with changes in the inflammatory cell infiltrate.

MATERIALS AND METHODS

34 cases representing lesions with both intraepidermal and subepidermal bullae were examined using immunoperoxidase staining methods and antibodies targeting antigens for histiocytes (CD68), B cells (CD20+), T cells (CD3+), T cells with cytotoxic potential (T cell intracellular associated antigen, TIA1+) and activity (granzyme B, GRB+). The adjacent normal skin (lesions) and an additional five cases of normal skin were also examined (controls).

RESULTS

The transition from normal skin to lesional skin (lesions with intraepidermal and subepidermal bullae) was associated with a significant increase (p< or =0.05) in the density of total inflammatory cell infiltrate, CD68+ cells, CD3+ T lymphocytes, CD20+ B lymphocytes, TIA1+ -resting cytotoxic T cells and GRB+ T cells with cytotoxic activity.

CONCLUSIONS

The increase in inflammatory cell infiltrate during the transition from normal to lesional skin may reflect the presence of an increased antigenicity of the lesional cells or a response to some basement membrane components. CD68+ and CD3+ cells, especially the resting cytotoxic ones, achieved numerical dominance in these lesions. Cell-mediated immunity seems to have critical role in the development of these lesions.

Polymorphic eruption of pregnancy

Polymorphic eruption of pregnancy (PEP) is a benign, self-limiting, pruritic disorder of pregnancy, which usually affects the primigravida during the last trimester or immediately postpartum. Its pathogenesis is unclear and its clinical manifestations are variable, leading frequently to an incorrect diagnosis. In cases of PEP the histological findings are nonspecific and the laboratory results, including direct immunofluorescence (DIF) and indirect immunofluorescence (IIF), are negative. Polymorphic eruption of pregnancy is not associated with any fetal risk and symptomatic treatment is all that is usually required. In this review we present the clinical presentation of PEP and a differential diagnosis which defines PEP as a separate entity. We will also review all current data of possible etiologic factors, histologic and immunologic findings, prognosis and therapy.