Detection of IgE autoantibodies to BP180 and BP230 and their relationship to clinical features in bullous pemphigoid

BACKGROUND

IgE autoantibodies are considered to be involved in the pathogenesis of bullous pemphigoid (BP), particularly inflammatory and erythematous phenotypes.

OBJECTIVES

To develop reliable enzyme-linked immunosorbent assays (ELISAs) for the detection of IgE autoantibodies to both BP180 and BP230 in BP sera, and to compare the ELISA results with clinical features.

METHODS

We used commercially available IgG ELISAs to develop IgE ELISAs for both BP180 and BP230. To determine the influence of excess amounts of IgG autoantibodies, all normal and BP sera were tested before and after IgG adsorption. The results of the IgE ELISAs were statistically compared with various ELISAs and various clinical parameters, including our own severity scores and BP phenotypes.

RESULTS

IgG adsorption generally showed no changes in sensitivity and specificity for IgE ELISAs, although slight cross-reactivity of anti-IgE secondary antibody to IgG and interference of excess amounts of IgG autoantibodies to IgE reactivity were suggested. IgE autoantibodies to BP180 were found in 21 of 36 BP sera and IgE autoantibodies to BP230 were found in 18 of 36 BP sera. The results of IgG and IgE ELISAs for both BP180 and BP230 were well correlated. IgG and IgE anti-BP180 antibodies correlated with disease activity but IgG and IgE anti-BP230 autoantibodies did not. IgE anti-BP230 autoantibodies correlated with nodular phenotype but not erythematous phenotype.

CONCLUSIONS

The results of this study indicated that IgE autoantibodies to both BP180 and BP230 are frequently detected in BP sera. IgE anti-BP180 autoantibodies seemed to be pathogenic, while an association between IgE autoantibodies and inflammatory BP phenotype was not indicated.

Squamous cell carcinoma arising from lupus vulgaris with a >60-year history

We report the case of a 71-year-old Japanese man with squamous cell carcinoma arising from lupus vulgaris on the face, >60 years after the appearance of the lupus vulgaris. The red plaque on the patient's face had been diagnosed as a hemangioma or rosacea at several hospitals, although he had had lung tuberculosis at the age of 4 and his father died from lung tuberculosis at 38 years of age. Although lupus vulgaris was the most frequent clinical form of true skin tuberculosis until the 1960s, it has become rare since then. Malignant tumors are known to occur in individuals with lupus vulgaris, with a reported rate of 0.5-10.5%. In light of Japan's "graying society," tuberculosis is still an important disorder, and clinicians must remain aware of cutaneous tuberculosis.

Bullous pemphigoid arising in a patient with acquired perforating dermatosis

A middle-aged Japanese man who had been on haemodialysis treatment for diabetic nephropathy developed multiple itchy papules and nodules, which were histopathologically diagnosed as acquired perforating dermatosis. Two years later he developed oral lesions and subsequently numerous erosive plaques with necrotic crusts on the trunk and extremities. Histopathology of a papule showed a parakeratotic plug intermingled with basophilic, necrotic debris and collagen bundles, along with penetration of collagen bundles across the epidermis and subepidermal blister. Immunoblotting studies revealed IgG autoantibodies in the patient's serum, which reacted with the C-terminal and the NC16a domains of bullous pemphigoid (BP)180, indicating presence of BP. We searched the literature and found no other cases of an autoimmune blistering disease occurring in association with a perforating disorder. Possible injury to the basement membrane zone induced during the process of transepidermal elimination might be involved in the pathogenesis of the pemphigoid disease.

Assessing age-related change in Japanese mental foramen opening direction using multidetector computed tomography

OBJECTIVE

The purpose of this study was to investigate how the opening direction of the mental foramen (MF) changes with age in a Japanese population using multi-detector computed tomography (MDCT).

METHODS

Post-mortem MDCT scans of 121 Japanese subjects (66 males and 55 females) were carried out where all subjects possessed at least twenty teeth, including molar teeth, in the upper and lower jaws. Two angles of the mental foramen opening were measured, namely the superior-inferior angle in the coronal plane and anterior-posterior angle in the transverse plane, on the CT reconstructed images. The associations between age and these two angles were evaluated using a multiple regression analysis.

RESULTS

For male subjects, the relationship between the superior-inferior angle and age was a quadratic curve (p < 0.001). This angle increased until the subject reached their early 50s and then the angle decreased with age. In the transverse plane, there was a linear relation between the anterior-posterior angle and age (p=0.002).It was noted also that the angle decreased with age. By contrast, however, no significant associations between the two angles and age for either measurement were noted for female subjects. This study demonstrated that the opening direction of the mental foramen changes with age in Japanese male subjects. By contrast this change in the opening direction of the mental foramen was not demonstrated in Japanese female subjects. In male subjects, the opening direction moves superiorly until the individual reaches their early 50s, and then moves inferiorly with advancing age. It also shifts from a posterior to an anterior position with age.

CONCLUSION

These observed change differ from the results of previous studies. The findings could be useful for forensic science as they demonstrate a change in the position of mental foramen in a sample of contemporaneous male Japanese subjects.

Clinical and immunological studies of 49 cases of various types of intercellular IgA dermatosis and 13 cases of classical subcorneal pustular dermatosis examined at Kurume University

BACKGROUND

Intercellular IgA dermatosis (IAD) is a subset of autoimmune bullous disease exclusively with IgA antikeratinocyte cell-surface antibodies. The classification and pathogenesis of this condition are still obscure.

OBJECTIVES

To classify IAD and study its pathogenesis.

METHODS

From our cohort of 5402 cases of autoimmune bullous disease, we selected 49 cases of various types of intercellular IgA dermatosis (IAD) and 13 cases of classical subcorneal pustular dermatosis (SPD), for which sera and information were available. We studied these cases clinically and immunologically.

RESULTS

There were 17 SPD-type IAD, 12 intraepidermal neutrophilic IgA dermatosis (IEN)-type IAD, two IgA-pemphigus vegetans, four IgA-pemphigus foliaceus, six IgA-pemphigus vulgaris and eight unclassified IAD cases. There was no sex predominance, and the average age at disease onset was 45·9 years. Clinically, bullous and pustular skin lesions developed on various sites, particularly intertriginous areas. Histopathology showed intraepidermal blisters or pustules at the upper epidermis in the SPD-type and at the midepidermis in the IEN-type. Immunological studies revealed that direct immunofluorescence, indirect immunofluorescence of normal human skin and enzyme-linked immunosorbent assays (ELISAs) of recombinant proteins of desmogleins and desmocollins frequently showed positive results, although no antigens were detected in many cases. All cases of classical SPD, which showed no positive immunological results, were indistinguishable clinically and histopathologically from SPD-type IAD.

CONCLUSIONS

The present study of the largest cohort of cases of IAD showed that the major subtypes are SPD and IEN, and that the combination of indirect immunofluorescence and ELISAs of desmogleins and desmocollins, in addition to direct immunofluorescence, was useful for the diagnosis of IAD and its subtypes.

A Predictive Model of Plasma Lamotrigine Levels

Introduction: Lamotrigine is one of several mood stabilizers and its effects for the treatment and prevention of depressive episodes, particularly in bipolar disorder, are generally accepted. Although the findings about a therapeutic window of lamotrigine are yet to be determined, it seems important to obtain information on individual pharmacokinetic peculiarities. This study was conducted to formulate the predictive model of plasma lamotrigine levels. Methods: Using the data of 47 patients whose lamotrigine levels, liver function, and renal function were measured, predictive models of lamotrigine levels were formulated by stepwise multiple regression analyses. The predictive power of the models was compared using another dataset of 25 patients. Results: Two models were created using stepwise multiple regression. The first model was: plasma lamotrigine level (μg/mL)=2.308+0.019×lamotrigine dose (mg/day). The second model was: plasma lamotrigine level (μg/mL)=0.08+0.024×lamotrigine dose (mg/day)+4.088×valproate combination (no=0, yes=1). The predictive power of the second model was better than that of the first model. Discussion: The present study proposes a prompt and relatively accurate equation to predict lamotrigine levels.

Usefulness of a Simple Immunohistochemical Staining Technique to Differentiate Anti-p200 Pemphigoid From Other Autoimmune Blistering Diseases: A Report of 2 Cases

Anti-p200 pemphigoid is a rare autoimmune subepidermal blistering disease characterized by the presence of circulating immunoglobulin G antibodies directed against laminin gamma-1, a 200-kDa protein located in the lamina lucida of the basement membrane. We review the clinical, histopathological and immunological characteristics of the first 2 cases described in Spain. Anti-p200 pemphigoid shares histopathological and immunopathological findings with epidermolysis bullosa acquisita, the main entity in the differential diagnosis. However, its management follows the same guidelines as those used for bullous pemphigoid. The diagnosis is confirmed by immunoblotting, which is a complex technique available in few centers. We propose the immunohistochemical detection of collagen type IV on the floor of the blister, combined with standard immunofluorescence techniques, as a simple, accessible alternative to differentiate anti-p200 pemphigoid from epidermolysis bullosa acquisita.

Clinical and immunological outcomes of high- and low-dose rituximab treatments in patients with pemphigus: a randomized, comparative, observer-blinded study

BACKGROUND

Rituximab is a promising therapy in pemphigus. However, there is no consensus on optimum dose.

OBJECTIVES

To compare the efficacy, in terms of clinical and immunological outcomes in patients with pemphigus, of a high (2 × 1000 mg) vs. a low dose (2 × 500 mg) of rituximab.

METHODS

This was a randomized, observer-blinded trial wherein 22 patients with pemphigus were randomized into two treatment groups. Patients received either two doses (day 0 and day 15) of 1000 mg rituximab or 500 mg rituximab, and were followed up for 48 weeks. Clinical activity was assessed by a blinded investigator. Indices of enzyme-linked immunosorbent assays (ELISAs) for desmoglein (Dsg)1 and Dsg3, and CD19 cell count were examined at regular intervals.

RESULTS

There was no statistically significant difference in early and late clinical end points, and total cumulative dose of corticosteroids between the two groups. At week 40, the fall in Ikeda severity score was significantly more in the 2 × 1000 mg group than in 2 × 500 mg group (P = 0·049). Patients in the 2 × 500 mg group received a significantly higher cumulative dose of azathioprine (P = 0·018). The ELISA indices of Dsg1 and Dsg3 showed a statistically significant decline in the 2 × 1000 mg group only. B cell repopulation occurred earlier in the 2 × 500 mg group by 8 weeks.

CONCLUSIONS

A few clinical and immunological study parameters have suggested improved outcomes in patients receiving high-dose (2 × 1000 mg) rituximab.