Immunohistochemical diagnosis of mucous membrane pemphigoid.

BACKGROUND: Mucous membrane pemphigoid (MMP) is an autoimmune subepithelial blistering disease with predominant involvement of mucosal surfaces. It is usually diagnosed by direct immunofluorescence microscopy of frozen biopsies, demonstrating linear deposits of complement, IgG or IgA along the basement membrane. The aim of this study was to investigate the utility of immunohistochemistry on formalin-fixed, paraffin-embedded tissue biopsies for the diagnosis of MMP and to compare its sensitivity to that of direct immunofluorescence microscopy. METHODS: We examined 50 biopsies from 34 patients with immunologically confirmed MMP by immunohistochemistry for C3d, C4d, IgG and IgA. RESULTS: Linear deposits of C3d were detected in 46% of biopsies, and 53% of patients had at least one biopsy positive for C3d. Linear deposits of C4d were detected in 52% of biopsies and 59% of patients had at least one biopsy positive for C4d. Overall, 56% of biopsies and 68% of patients were positive by either C3d or C4d or both stainings. The sensitivity of either staining in mucosal biopsies was lower than in skin samples. Basement membrane deposits of IgG or IgA could not be detected in any biopsy. CONCLUSIONS: Our findings demonstrate that immunohistochemistry for C3d or C4d is a helpful screening procedure for cases of suspected MMP where frozen tissue is not readily available. Negative findings, however, do not exclude a possible diagnosis of MMP and should prompt an additional biopsy for direct immunofluorescence studies. Immunohistochemical detection of IgG or IgA cannot yet be used for the diagnosis of MMP.

Adjuvant treatment of severe/refractory bullous pemphigoid with protein A immunoadsorption.

BACKGROUND: While depletion of circulating autoantibodies using immunoadsorption (IA) is an established therapeutic approach in patients with pemphigus vulgaris, IA has only sporadically been used in other autoimmune bullous disorders. Although bullous pemphigoid (BP) usually responds well to topical and systemic corticosteroids, rapid depletion of serum autoantibodies may be an effective adjuvant treatment option in patients with severe and/or refractory disease. PATIENTS AND METHODS: Case series of 20 patients (13 women, 7 men; mean age 78.6 years; range 56-94 years) with severe or refractory BP. In addition to oral prednisolone (0.25-0.5 mg/kg/day), dapsone (1.0-1.5 mg/kg/day), and clobetasol propionate 0.05 % ointment (lesional application, twice daily), treatment consisted of protein A IA (three sessions on consecutive days). The mean follow-up period was 33.6 months (1-84 months). RESULTS: The majority of patients showed a rapid and sustained response. One month after treatment, eight patients (42 %; 19 patients were included in the follow-up) were in complete remission; at the last follow-up visit (after 1 to 84 months), that number was 13 (68 %). Not only was there an initial drop in anti-BP180 autoantibodies (by 92 %), the effect also continued after one and three months, with mean autoantibody levels at 26 % and 13 % of baseline, respectively (p < 0.001). Both previously treated and treatment-naive patients showed a significant reduction in anti-BP180NC16A antibody levels throughout the observation period. Adverse events occurred in 13 of the 20 patients (65 %). Three were severe of which two were likely or probably related to IA. CONCLUSION: Immunoadsorption is an effective adjuvant treatment option for (the usually elderly) patients with severe and/or refractory BP.

Adjuvante Behandlung des schweren/refraktären bullösen Pemphigoids mit Protein-A-Immunadsorption.

HINTERGRUND: Mittels Immunadsorption (IA) können Immunglobuline und Immunkomplexe aus dem Plasma entfernt werden. Während dieses therapeutische Verfahren beim Pemphigus vulgaris bereits etabliert ist, wird es bei anderen blasenbildenden Autoimmundermatosen bislang nur sporadisch eingesetzt. Das bullöse Pemphigoid (BP) spricht zwar meist gut auf eine Therapie mit topischen und systemischen Kortikosteroiden an, jedoch könnte bei Patienten mit ausgedehnten Läsionen oder bei einem Rezidiv die rasche Reduktion der pathogenen Autoantikörper eine effektive adjuvante Therapie darstellen. PATIENTEN UND METHODIK: Fallserie mit 20 Patienten (13 Frauen, 7 Männer; mittleres Alter 78,6 Jahre; 56-94 Jahre) mit schwerem oder refraktärem BP, die zusätzlich zur Basistherapie bestehend aus Prednisolon (0,25-0,5 mg/kg/d), Dapson (1,0-1,5 mg/kg/d) und Clobetasolpropionat 0,05 % Salbe (läsional 2 x/d) mit Protein-A-IA (3 IAs an aufeinander folgenden Tagen) behandelt wurden. Die durchschnittliche Nachbeobachtungszeit betrug 33,6 Monate (1-84 Monate). ERGEBNISSE: Bei der Mehrzahl der Patienten zeigte sich ein rascher und langandauernder Therapieeffekt. Nach einem Monat befanden sich acht Patienten (von 19 nachbeobachteten, 42 %) und zum Zeitpunkt des letzten Kontakts (nach 1-84 Monaten) 13 Patienten (68 %) in kompletter Remission. Die Anti-BP180-Autoantikörper wurden nicht nur initial (um 92 %) gesenkt, sondern lagen auch nach ein und drei Monaten im Mittel bei 26 % und 13 % des Wertes vor Therapiebeginn (p < 0,001). Bei Differenzierung in vortherapierte bzw. therapienaive Patienten zeigten sich in beiden Subgruppen signifikante Absenkungen der Anti-BP180NC16A-Antikörper-Spiegel zu allen Zeitpunkten. Unerwünschte Ereignisse traten bei dreizehn (65 %) der 20 Patienten auf, Drei der Ereignisse waren schwer und zwei davon wahrscheinlich oder möglicherweise in Zusammenhang mit der IA. SCHLUSSFOLGERUNGEN: Die IA ist eine effektive adjuvante Therapieoption bei den in aller Regel älteren Patienten mit einem schweren und/oder therapierefraktären BP.

Multiple and repeated sampling increases the sensitivity of direct immunofluorescence testing for the diagnosis of mucous membrane pemphigoid.

BACKGROUND: Mucous membrane pemphigoid (MMP) is an autoimmune disease characterized by the predominant blistering of mucosal surfaces and the linear deposition of complement, IgG, or IgA along the basement membrane detected by direct immunofluorescence (DIF) test. OBJECTIVE: To assess the impact of multiple and repeated DIF sampling on establishing the diagnosis of MMP. METHODS: We reviewed the results of DIF studies in 136 nonlesional biopsies from 78 patients who were immunologically confirmed to have MMP. RESULTS: Thirty-six of 52 patients (69%) who underwent only 1 biopsy at the first workup were positive. In 13 cases, the initial single biopsy was negative, and later biopsies were positive. Twenty-two of 26 patients (85%) who underwent multiple biopsies at the initial workup showed ≥1 positive DIF test result. Simultaneously obtained biopsies yielded discordant positive and negative findings in 11 patients. Overall, 74 of 78 patients (95%) had ≥1 positive result by DIF test. In the remaining 4 cases, the diagnosis was confirmed by the detection of circulating autoantibodies against BP180. LIMITATIONS: This is a retrospective, single-center study. CONCLUSION: Our data demonstrate that multiple and repeated biopsies increase the sensitivity of the DIF test for MMP diagnosis. Negative DIF test findings in cases clinically suggestive of MMP should prompt repeat biopsies.

Histopathology of panniculitis--aspects of biopsy techniques and difficulties in diagnosis.

BACKGROUND: Clinical and histologic diagnosis of panniculitis may be difficult. The patients usually present with erythematous subcutaneous nodules with or without additional symptoms. If a skin biopsy does not include enough subcutaneous fat, histopathologic assessment is limited and the correct diagnosis may be delayed and require further sampling. PATIENTS AND METHODS: To illustrate the difficulties in the diagnosis of panniculitis, we performed a retrospective examination of four patients with different forms of panniculitis. RESULTS: In two patients with subcutaneous panniculitis-like T cell lymphoma and lupus panniculitis, the correct diagnosis could only be ascertained after a delay of several months because repeated biopsies had to be obtained throughout the course of disease. In two further patients with cold panniculitis and pancreatic panniculitis, clinicians did not even suspect an inflammatory process in the subcutaneous tissue. The correct diagnosis was made with a deep punch biopsy that included subcutaneous fat. CONCLUSIONS: On the one hand, these examples demonstrate the importance of sampling subcutaneous tissue when obtaining routine punch biopsies. On the other hand, in cases where the diagnosis is uncertain, it is necessary to perform large and deep incisional biopsies.

Rituximab for treatment-refractory pemphigus and pemphigoid: a case series of 17 patients.

BACKGROUND: Rituximab has been increasingly used in autoimmune blistering dermatoses, mainly in pemphigus. However, only a few larger case series are available on this subject and information on the efficacy of retreatment with rituximab during relapses is lacking. OBJECTIVE: We sought to determine efficacy and adverse effects of adjuvant rituximab. METHODS: Seventeen patients with refractory autoimmune blistering dermatoses (pemphigus vulgaris [PV], n = 8; pemphigus foliaceus [PF], n = 2; bullous pemphigoid [BP], n = 2; mucous membrane pemphigoid, n = 5) were treated 4 times with rituximab at an individual dose of 375 mg/m(2) in weekly intervals or twice with 1000 mg 2 weeks apart. Six of 8 patients with a relapse after this regimen received rituximab again twice with 1000 mg in a 2-week interval. RESULTS: All lesions cleared in 14 patients (7 PV, two PF, two BP, 3 mucous membrane pemphigoid), whereas partial healing was found in 3 others (one PV, two mucous membrane pemphigoid). Relapses occurred in 8 patients (5 PV, two PF, one BP). Retreatment with rituximab again resulted in complete (two PV, one PF, one BP) or partial (two PV) remission. Serious side effects associated with rituximab were not observed. LIMITATIONS: Rituximab has been combined with various other immunosuppressive or immunomodulatory treatments. CONCLUSION: Adjuvant rituximab is effective and well tolerated not only in patients with pemphigus but also with pemphigoid. Efficacy and safety of rituximab are maintained when it is readministered during relapses.

Trichoadenoma of Nikolowski is a distinct neoplasm within the spectrum of follicular tumors.

BACKGROUND: Trichoadenoma is a rare benign follicular tumor first described by Nikolowski 50 years ago. Both trichoadenoma and desmoplastic trichoepithelioma are composed of cords of epithelial cells and cornifying cysts embedded in sclerotic stroma. In trichoadenoma the cystic component predominates, while desmoplastic trichoepithelioma is a mostly solid neoplasm. Therefore trichoadenoma was suggested to represent a cystic variant of desmoplastic trichoepithelioma. OBJECTIVE: The aim of this study was to investigate whether the morphologic overlap between trichoadenoma and desmoplastic trichoepithelioma translates into a similar immunohistochemical profile. METHODS: We studied 19 trichoadenomas and 21 desmoplastic trichoepitheliomas for cytokeratin 20, Ber-EP4, and androgen receptor expression. RESULTS: Eighteen of 19 trichoadenomas and all desmoplastic trichoepitheliomas demonstrated the presence of Merkel cells as detected by a monoclonal antibody against cytokeratin 20. In contrast, while all desmoplastic trichepitheliomas were positive for Ber-EP4, only 4 of 19 trichoadenomas showed any kind of reactivity for this marker. None of the trichoadenomas or desmoplastic trichoepitheliomas expressed androgen receptor. LIMITATIONS: This study is limited by the moderate number of these rare tumors available for immunohistochemical analysis. CONCLUSION: Our data demonstrate that trichoadenoma typically retains cytokeratin 20-positive Merkel cells but lacks Ber-EP4 and androgen receptor expression. Trichoadenoma is a distinct follicular tumor related but not identical to desmoplastic trichoepithelioma.

Autoantibodies against epidermal transglutaminase are a sensitive diagnostic marker in patients with dermatitis herpetiformis on a normal or gluten-free diet.

BACKGROUND: Dermatitis herpetiformis (DH) is a cutaneous manifestation of gluten-sensitive enteropathy (celiac disease). Patients with DH demonstrate circulating IgA antibodies against epidermal transglutaminase (eTG) and tissue transglutaminase (tTG). It has been suggested that eTG is the autoantigen of DH. OBJECTIVE: The purpose of this study was to characterize the autoimmune response to eTG and tTG in patients with DH on a normal or gluten-free diet (GFD). METHODS: Sera from 52 patients with DH were studied for the presence of IgA antibodies to eTG and tTG by enzyme-linked immunosorbant assay. In 38 patients, serum was obtained before initiation of a GFD, whereas 14 patients had been on a GFD for at least 2 years. RESULTS: Autoantibodies against eTG were detected in 36 of 38 patients (95%) and those against tTG in 30 of 38 patients (79%) with DH on a normal diet. Of 14 patients on a long-term GFD, 7 patients were free of DH lesions and did not require dapsone treatment. None of these patients showed circulating antibodies against eTG or tTG. The remaining 7 patients on a GFD were not able to stop taking dapsone. All these patients demonstrated anti-eTG antibodies, whereas only 3 of them showed additional reactivity against tTG. LIMITATION: Autoantibody levels against eTG and tTG before and after introduction of a GFD were not examined in the same patients. CONCLUSION: Our data suggest that antibodies to eTG are the most sensitive serologic marker in treated and untreated patients with DH and confirm the central role of eTG in the pathogenesis of this disease.

Histopathology of anti-laminin 5 mucous membrane pemphigoid.

BACKGROUND: Anti-laminin 5 mucous membrane pemphigoid (MMP) is an autoimmune blistering disease characterized by autoantibodies against the major basement membrane component laminin 5 (laminin 332, epiligrin). OBJECTIVE AND METHODS: We reviewed 17 biopsy specimens from 9 patients with anti-laminin 5 MMP in an attempt to define typical histopathologic features of the disease. RESULTS: Fifteen specimens showed subepidermal blister formation, while two biopsy specimens revealed an epithelial ulcer. In 11 biopsies a sparse to moderate inflammatory infiltrate composed of lymphocytes and neutrophils with some eosinophils was observed. Four biopsies showed a dense infiltrate dominated by neutrophils in two cases and by eosinophils in one case. The remaining biopsy revealed a dense lymphoplasmacellular infiltrate without granulocytes. Scarring of the upper dermis was present only in 5 specimens. Immunohistochemical analysis localized type IV collagen to the dermal side of the blister, suggesting that split formation occurred within the lamina lucida of the cutaneous basement membrane. LIMITATIONS: The number of patients studied was relatively small. CONCLUSIONS: Histopathology of anti-laminin 5 MMP is characterized by subepidermal blistering and a sparse to moderate superficial lymphohistiocytic infiltrate with neutrophils and/or eosinophils. Both infiltrate density and composition may vary, making anti-laminin 5 MMP indistinguishable from other autoimmune subepidermal blistering diseases by histopathology alone. Scarring is present only in a minority of cases and is not a sensitive clue to the diagnosis of anti-laminin 5 MMP.

Black tea dressings - a rapidly effective treatment for facial dermatitis.

Background: Facial dermatitis is a common dermatologic condition. It is usually treated with either topical corticosteroids or calcineurin inhibitors. However, the use of these drugs is limited by side effects, including skin atrophy, local immunosuppression and possible oncogenicity. Objective: The aim of the study was to evaluate the use of wet dressings with black tea for treating facial dermatitis. Methods: We performed a prospective, open, uncontrolled before-after study enrolling 22 patients with atopic or contact facial dermatitis who were treated with black tea dressings and an emollient cream over 6 days. Disease severity was assessed using the (1) Facial Eczema Area and Severity Index, (2) Visual analog scale for pruritus, (3) Investigator`s Global Assessment score, and (4) Patient's Self-Assessment score. The study was registered at www.ClinicalTrials.gov as NCT02941432. Results: A dramatic and highly significant reduction of all four disease activity scores occurred within the first 3 days of treatment and the patients continued to improve between days 3 and 6. No side effects were observed. Conclusion: Black tea dressings represent an effective treatment option for facial dermatitis. Its advantages include lack of side effects, low cost, and easy availability.

Recommendations for the use of rituximab (anti-CD20 antibody) in the treatment of autoimmune bullous skin diseases.

Autoimmune bullous skin disorders are induced by autoantibodies against distinct adhesion complexes of the epidermal and dermal-epidermal junction. Since most of these disorders are characterized by a severe, potentially lethal course,they require long-term immunosuppressive treatment to reduce the de novo synthesis of pathogenic autoantibodies by B lymphocytes. Rituximab, a chimeric monoclonal antibody against CD20 on B lymphocytes, has shown promise in several case reports or cohort studies in the treatment of paraneo-plastic pemphigus,refractory cases of pemphigus vulgaris and foliaceus and in other autoimmune bullous disorders. Treatment with rituximab leads to depletion of pathogenic B-cells which may last up to 12 months resulting in a reduction of plasma cells secreting pathogenic autoantibodies. Rituximab is usually administered in an adjuvant setting at a dose of 375 mg/m(2) i.v.in weekly intervals for four consecutive weeks in addition to the standard immunosuppressive treatment. The present consensus statement of German-speaking dermatologists, rheumatologists and oncologists summarizes and evaluates the current evidence for the use and mode of application of rituximab in autoimmune bullous skin disorders.