Immunopathology of the placenta in pemphigoid gestationis and linear IgA disease

Autoimmune bullous diseases in pregnancy: clinical and epidemiological characteristics and therapeutic approach

Autoimmune bullous dermatoses are a heterogeneous group of diseases with autoantibodies against structural skin proteins. Although the occurrence of autoimmune bullous dermatoses during pregnancy is low, this topic deserves attention, since the immunological and hormonal alterations that occur during this period can produce alterations during the expected course of these dermatoses. The authors review the several aspects of autoimmune bullous dermatoses that affect pregnant women, including the therapeutic approach during pregnancy and breastfeeding. Gestational pemphigoid, a pregnancy-specific bullous disease, was not studied in this review.

Gestational pemphigoid

Gestational pemphigoid (pemphigoid gestationis, PG) is a rare autoimmune skin disorder occurring characteristically during pregnancy. Autoantibodies against placental BP180 (also known as BPAG2 or collagen XVII) cause damage to the skin basement membrane, resulting in severe itching and blistering rash over the body and the extremities. The diagnosis of PG is confirmed by immunofluorescence analysis of a skin biopsy, while serum levels of pemphigoid antigen BP180 antibody can be used to assess disease activity. PG with mild symptoms can be treated with topical corticosteroids, while oral corticosteroids are the mainstay in treatment of severe PG. PG usually flares up at the time of delivery, and resolves spontaneously shortly after. However, relapses in subsequent pregnancies are common. As PG has been linked to the risk of prematurity and fetal growth restriction, prenatal monitoring jointly by a dermatologist and an obstetrician is recommended. Mothers should also be informed of the potential risk of re-activation of the disease in subsequent pregnancies and during hormonal contraception.

Pregnancy dermatoses: diagnosis, management, and controversies

Some aspects regarding the etiology and the nosologic classification of various pregnancy dermatoses are highly controversial. While some authors highlight the existence of premises allowing several skin disorders to be re-grouped within broader disease concepts, others underline the absence of clear, undisputed etiopathogenetic data that could support such classifications. This review exhaustively analyzes the various pregnancy dermatoses (pemphigoid gestationis, intrahepatic cholestasis of pregnancy, impetigo herpetiformis, polymorphic eruption of pregnancy, and the papular dermatoses of pregnancy [prurigo of pregnancy, pruritic folliculitis of pregnancy, and the new classification, atopic eruption of pregnancy]) in an attempt to shed light over this confusing and disputed domain, while subsequently offering an algorithmic approach to their diagnosis and management. While for pemphigus gestationis, intrahepatic cholestasis of pregnancy, and impetigo herpetiformis, specific diagnostic tests such as histopathology, immunofluorescence, or laboratory investigations will confirm the diagnosis, the identification of the other types of pregnancy dermatoses is based only on clinical criteria. In this context, the review argues for the inclusion of the whole group represented by the papular dermatoses of pregnancy within the broad spectrum of polymorphic eruption of pregnancy, separating each of these entities by focusing on their onset: early-onset polymorphic eruption of pregnancy (comprising prurigo of pregnancy, pruritic folliculitis of pregnancy, and atopic eruption of pregnancy) and late-onset polymorphic eruption of pregnancy. In light of the same practical approach guiding it, the review provides updated treatment strategies for each of these conditions.

A case of gestational diabetes arising following treatment with glucocorticosteroids for pemphigoid gestationis

A case of pemphigoid gestationis, a rare autoimmune disease unique to pregnancy, is described. To control the skin lesions systemic corticosteroids were required. The patient developed gestational diabetes mellitus. The pregnancy continued to 37 weeks and a live male infant was delivered. There was no evidence of macroscopic changes in the placenta. The skin lesions resolved in the postpartum period.

Dermatose por IgA linear induzida pela gestação

A dermatose por IgA linear é doença bolhosa auto-imune subepidérmica rara, caracterizada pelo depósito linear de IgA na zona da membrana basal da epiderme. Nos relatos de gestação em pacientes com essa dermatose, nota-se sempre melhora do quadro clínico. Contrariando essas observações,é apresentado caso de dermatose por IgA linear induzida pela gestação, que demonstrou boa resposta terapêutica à dapsona e prednisona , sem complicações materno-fetais.

Chronic bullous disease of childhood and linear IgA disease of adults are IgA1-mediated diseases

Linear IgA disease is characterized by the presence of linear IgA deposits at the basement membrane zone of the skin, and in some cases by circulating basement membrane zone antibodies. The disease occurs in both adults and children, and is designated adult linear IgA disease in the former and chronic bullous disease of childhood in the latter. The subclass distribution of the circulating and bound basement membrane zone antibodies was studied in 32 children and eight adults. The results were compared with five dermatitis herpetiformis patients and five normal controls. The circulating antibodies (39 patients) and the cutaneous deposits (39 patients) were IgA1 in all 40 patients with linear IgA disease. The cutaneous deposits in dermatitis herpetiformis were also all IgA1, and no circulating antibodies were detected. The controls were all negative. This large series of children and adults with linear IgA disease demonstrates that the circulating and cutaneous basement membrane zone deposits are all IgA1, and suggests that linear IgA disease is an IgA1-mediated disease.

Linear IgA disease and pregnancy

BACKGROUND

Although many patients with linear IgA dermatosis (LAD) are young and have persistent disease, little is known about the interactions between LAD and pregnancy.

OBJECTIVE

Our purpose was to study the effects of LAD on pregnancy, and vice versa.

METHODS

Our study included 12 patients with LAD who underwent a total of 19 pregnancies.

RESULTS

In all patients the disease improved during pregnancy, enabling therapy to be reduced or stopped. Dapsone was taken by patients during 11 pregnancies, and no adverse effects were seen. No patients had problems in labor. Most patients had a relapse approximately 3 months post partum, even if they had previously been in remission. In two patients, disease started within 3 months of delivery. Fetal outcome was unaffected in all but one fetus, who had a single transient blister.

CONCLUSION

We found no contraindication to pregnancy in patients with LAD. We recommend that therapy be reduced or stopped whenever possible during pregnancy and that patients be counseled about the possibility of a relapse post partum.

Anti-HLA antibodies in pemphigoid gestationis (herpes gestationis)

Pemphigoid gestationis (PG; herpes gestationis) is a rare autoimmune disease associated with pregnancy, currently defined by the presence of complement deposition along the cutaneous basement membrane zone. It is known to be associated with HLA-DR3 and DR4, and an increase in anti-HLA antibodies in those with a history of PG has been reported. We have studied 39 patients with an immunofluorescence-confirmed diagnosis of PG for the presence and specificity of anti-HLA antibodies. Anti-HLA antibodies were found in all 39 patients. Specificity was against class I antigens in 98% (controls 10%; P < 0.001) and class II antigens in 25% (controls 8.5%; P < 0.001). Almost all anti-HLA antibodies were cytotoxic. The universal presence of anti-HLA antibodies in PG suggests that they may develop coincidently with antibasement membrane antibodies, and may reflect a common immunological event.

Secondary autoimmune diseases in herpes gestationis (pemphigoid gestationis)

BACKGROUND

Herpes gestationis (HG) is an autoimmune disease of the skin that occurs exclusively in association with pregnancy (or trophoblastic disease). It is associated with the HLA-DR3 and -DR4 antigens that are also associated with several other autoimmune diseases. HG has previously been reported in association with Graves' disease.

OBJECTIVE

Our purpose was to determine the frequency of other autoimmune disease(s) in patients with a history of HG.

METHODS

Seventy-five patients with a history of HG were studied for the frequency of other autoimmune diseases.

RESULTS

We found an increased frequency of Graves' disease in patients with a history of HG. Those with HG have an increased risk for the development of other autoantibodies. There is an increased frequency of autoimmune diseases in the family members of patients with HG.

CONCLUSION

Secondary autoimmune disease in HG is unusual, but does occur. The most frequent is Graves' disease.

Isolated basal keratinocytes express pemphigoid gestationis antigen

Basal keratinocytes were isolated from epidermal cell suspensions prepared by trypsinization of normal human skin. Cells were identified as basal cells by their adherence to collagen and confirmed as basal cells by the presence of pemphigoid antigen. Using an indirect immunofluorescence assay, cells were found to express pemphigoid gestationis-related antigen. Sera from patients with pemphigoid gestationis reacted in one of two immunofluorescence patterns: either polar, in a pattern similar to that observed with bullous pemphigoid serum, or with uniform staining around the cell periphery. Pemphigoid gestationis-related antigen is expressed by isolated basal keratinocytes and is resistant to trypsinization. The heterogeneity of immunofluorescence patterns may correspond to the heterogeneity of antigen recognition by different patients with pemphigoid gestationis.

Fetal risks in herpes gestationis

BACKGROUND

The potential risks to the fetus in herpes gestationis have long been a controversial subject, but because of the rarity of the disease, have only occasionally been studied.

OBJECTIVE

The purpose of this study was to determine the incidence of fetal complications in herpes gestationis.

METHODS

We collected and analyzed the obstetric histories of 74 patients and compared their involved pregnancies with their uninvolved pregnancies.

RESULTS

There was an obvious tendency for premature delivery associated with herpes gestations. A slight tendency toward small-for-gestational-age newborns associated with herpes gestationis was confirmed, but, perhaps surprisingly, no increase in spontaneous abortions or stillbirths was noted. The use of systemic steroids did not appear to influence risk.

CONCLUSION

Herpes gestationis is associated with an increase in prematurity and small-for-gestational-age infants.

Antigen-presenting cells in the skin and placenta in pemphigoid gestationis

In pemphigoid gestationis (PG), one of the major initiating events is the aberrant expression of the class II molecules of the major histocompatibility complex in the placenta. We used a panel of 13 monoclonal antibodies to investigate the phenotype of the MHC class II positive antigen-presenting cells (APC) in the skin and placenta in PG. In the skin, the APC show reactivity with a variety of macrophage markers and the CDI marker of Langerhans cells. By contrast, the MHC class II positive cells in the placenta showed no reactivity with macrophage or Langerhans cell markers, but were the cytokeratin-positive trophoblast or vimentin-positive stromal cells.

Western blot analysis of the antigen in pemphigoid gestationis

Using an immunoblotting technique, sera from 25 patients with pemphigoid gestationis were examined and tested against epidermal and dermal extracts of normal skin. The major antigen recognized by seven patients' sera was a molecule of 180 kDa, pemphigoid gestationis antigen, extractable only from the epidermis. Sera from 18 patients with bullous pemphigoid were studied as positive controls and the major antigen recognized was a larger molecule of 220 kDa. There was some degree of shared recognition of antigens with three patients with pemphigoid gestationis recognizing the 220 kDa bullous pemphigoid antigen. In addition one bullous pemphigoid serum recognized the 180 kDa pemphigoid gestationis antigen. The dominant pemphigoid gestationis antigen, however, differs from bullous pemphigoid antigen.