Immunogenetics of drug-induced bullous diseases

A retrospective study of antihypertensives in pemphigus: a still unchartered odyssey particularly between thiols, amides and phenols

INTRODUCTION

Autoimmune pemphigus diseases comprise several entities with serious prognoses, including the pemphigus vulgaris (PV) group and pemphigus foliaceus (PF) group. Antihypertensives are suspected to be one of the factors triggering/sustaining pemphigus. Here, the data of pemphigus patients regarding arterial hypertension (AH) and taking potentially noxious drugs were statistically analyzed in a setting of a Polish university dermatology department.

MATERIAL AND METHODS

Medical histories of pemphigus patients (40 admissions of 24 female patients - 13 PV, 11 PF; and 102 admissions of 38 male patients - 24 PV, 14 PF), diagnosed at both immunopathological and biochemical-molecular levels, were studied.

RESULTS

Ten of 16 (62.50%) AH-positive PV patients received known PV triggers/sustainers 11 times (1-3 per patient). Fourteen of 15 (93.33%) AH-positive PF patients received known PF triggers/sustainers 21 times (1-3 per patient). No differences in numbers of patients taking potentially culprit drugs were shown between PV and PF (Fisher's exact test: p = 0.0829; Yates' χ(2) test: p = 0.1048). The most frequently used culprit drugs were ramipril in PV and enalapril in PF. On average, each PV/PF AH-positive patient received 3.161 different antihypertensives in his/her history of admissions (2.155 antihypertensives per admission).

CONCLUSIONS

Drug triggering should be suspected in every case of newly diagnosed or exacerbated pemphigus, as eliminating possible PV/PF triggers/sustainers may alleviate the clinical symptoms and enable the decrease of dose/range of immunosuppressants regardless of pemphigus form. Eliminating possible drug PV/PF triggers/sustainers may alleviate the clinical symptoms and enable the decrease of dose/range of immunosuppressants regardless of pemphigus form.

Immunogenetics of drug-induced skin blistering disorders. Part II: Synthesis

The overall immunopathogenesis relevant to a large series of disorders caused by a drug or its associated hyperimmune condition is discussed based upon examining the genetics of severe drug-induced bullous skin problems (sporadic idiosyncratic adverse events including Stevens–Johnson syndrome and Toxic epidermal necrolysis). New results from an exemplar study on shared precipitating and perpetuating inner causes with other related disease phenotypes including aphtous stomatitis, Behçets, erythema multiforme, Hashimoto’s thyroiditis, pemphigus, periodic fevers, Sweet’s syndrome and drug-induced multisystem hypersensitivity are presented. A call for a collaborative, wider demographic profiling and deeper immunotyping in suggested future work is made.

Investigation into the multidimensional genetic basis of drug-induced Stevens-Johnson syndrome and toxic epidermal necrolysis

OBJECTIVE

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare severe blistering skin diseases, which are mainly caused by drugs. The two idiosyncratic conditions are distinguished on the basis of the degree of blistering, possibly representing diseases at different ends of the same spectrum. A genetic predisposition has been postulated.

METHOD

We have retrospectively identified a heterogeneous group of patients with SJS and TEN (n = 73 cases, 141 matched controls) induced by a number of marketed drugs and evaluated effector candidate genetic predisposition. We have used a multivariate genetic analysis method for the first time to handle the heterogeneity of clinical presentation, drug etiology, ethnicity and gender in these adverse events.

RESULTS

Our results show that predisposition varied according to ethnicity. There was a correlation for SJS with HLA-B*44, DRB1*07 and with the MHC ancestral 57.1 haplotype (and its constituents) in subjects who self-reported as Caucasians, which did not differ with gender. The HLA-DRB and -DRQ genetic predisposition to SJS seemed to be distinct from that of TEN, but further work is needed for both conditions to identify the causal variants. No conclusion concerning correlations with different drugs could be made because of small numbers in each drug group.

CONCLUSION

This study stresses the importance of accurate clinical phenotyping, exemplifies a novel analysis method to dissect complicated samples and calls for collaborative prospective studies.

The immunogenetics of pemphigus vulgaris

Pemphigus vulgaris (PV) is an autoimmune blistering disease of the skin of unknown etiology. While various environmental factors have been implicated as triggering agents, HLA association is probably the most important predisposing factor. The aim of this review is to highlight the association of HLA with pemphigus vulgaris. In addition, we present recent results showing a possible association with the nonclassical HLA-G antigen.

Common ancestral origin of pemphigus vulgaris in Jews and Spaniards: a study using microsatellite markers

Pemphigus is a group of autoimmune blistering diseases of the skin and mucous membranes. The association of pemphigus with human leukocyte antigen (HLA) is widely accepted. It was described in many ethnic groups and in most countries of the world. Studies showed that the associated HLA haplotype in Jewish pemphigus vulgaris (PV) patients is HLA-B38, DRB1*0402, and DQB1*0302; or HLA-B35, DRB1*0402, and DQB1*0302. Similar associations with class II genes were found in Spanish non-Jewish PV patients. As Jews lived in Spain for hundreds of years and many converted to Christianity, the presence of the same HLA haplotype in the Jewish and Spanish PV suggests that they may share the same founder. Microsatellite markers which span the entire major histocompatibility complex (MHC) locus were used as genetic probes. They were utilized to dissect the MHC region in the search for possible common haplotypes, besides HLA, which may provide an answer to this question. It was found that in both cohorts, in addition to HLA class II genes, there are probably genes in the class I region which are associated with PV. Alleles belonging to the associated markers were used to construct haplotypes and to estimate genetic distances. The distance between the two PV cohorts is relatively short, but the distance between the Jewish patients and the Jewish controls is greater compared to the distance between Spanish patients and Spanish controls. In both PV populations, the same microsatellite haplotypes in addition to a common class II haplotype were found, suggesting that both patient populations originated from the same genetic stock and, therefore, share the same ancestral disease gene.

Pemphigus vulgaris in Jewish patients is associated with HLA-A region genes: mapping by microsatellite markers

Pemphigus vulgaris (PV) is the most severe autoimmune blistering disorder of the skin that is mediated by circulating autoantibodies against desmoglein 3 (Dsg3). It has been reported that in Jews the associated haplotype in PV is human leukocyte antigen (HLA) B38, DRB1*0402, DQB1*0302. Significant associations with HLA were observed also in non-Jews. Dsg3-specific T-cell responses were detected in PV patients but also in healthy individuals who were either carriers of the PV-associated DRB1*0402 allele or alleles that share similar or identical peptide binding motifs to DRB1*0402. This suggests that genes other than the classical major histocompatibility complex (MHC) genes are associated with the development of the autoimmune response. We used 16 microsatellite probes that span the entire MHC region to screen DNA samples from 38 PV patients and 76 healthy controls. Results demonstrated that some markers were associated with class II region including a TAP associated marker. However, four probes, D6S265, C_527, D6S510, and MOGC, which are all mapped to the region of HLA-A, were highly associated with PV. These results suggest that a gene, or genes in the class I region are important in the initiation of the autoimmune cascade. Activation/suppression of these genes might act as the trigger mechanism that starts the autoimmune destructive process.

Pemphigus vulgaris induced by D-penicillamine therapy in a patient with systemic sclerosis

D: -Penicillamine-induced pemphigus occurs infrequently, typically in patients with rheumatoid arthritis. We describe a patient with systemic sclerosis who experienced this complication 3 months after starting D -penicillamine therapy. Nikolsky's sign, histopathologic findings, and direct immunofluorescence all confirmed the diagnosis. Termination of disease progression required intravenous pulse glucocorticoids, azathioprine, and 3 courses of plasmapheresis. The presentation, treatment, and etiology of D -penicillamine-induced pemphigus are reviewed, and the incidence of this complication in scleroderma patients is examined.