The enigmatic autoimmune response in endemic pemphigus foliaceus

A Global View of Pemphigus: Geographical Variations

Pemphigus, an autoimmune intraepidermal bullous disease group with roughly eight distinct forms, includes pemphigus vulgaris (PV) and pemphigus foliaceus (PF) as its predominant global forms. Despite the increased utilization of global health records and reporting systems, epidemiological data remain limited and poorly categorized. Therefore, this study aimed to conduct a review to track, identify, and characterize cases of PV and PF published and categorized worldwide. A research question was formulated; studies were selected based on the inclusion criteria; and data from these publications were systematically collected, summarized, and presented using narrative descriptions. The search strategy yielded 3,212 articles, of which 95 underwent critical analysis and data extraction. Studies from 52 countries contributed to the dataset, covering various pemphigus variants. Notably, only two countries, Iran (18.87%) and South Korea (11.43%), accounted for approximately a third of the reported PV cases, while Brazil contributed 40.25% of the foliaceus variants cases documented in the literature. These findings offer valuable insights into the global distribution of pemphigus and inform future research and healthcare efforts.

Severe visceral leishmaniasis and COVID-19 coinfection in an immunosuppressed patient

Visceral leishmaniasis (VL) is an opportunistic disease in immunosuppressed individuals, who may present severe clinical conditions, such as the ones described in this patient. She lived in an endemic region for VL, and was possibly infected with L. (L.) infantum chagasi through the bite of a contaminated sand fly. This initial infection has triggered a pemphigus vulgaris condition by immunogenic proteins present in the mosquito's saliva. The immunosuppression caused by the use of high doses of corticosteroids to control the disease promoted a severe VL condition, with hepatosplenomegaly, thrombocytopenia and hemorrhages, requiring hospitalization and the onset of a subsequent SARS-CoV-2 infection. Due to the intensity of clinical manifestations related to VL, aggravated by COVID-19, she died two days after admission to the Clinical Hospital of Marilia Medical School (HC–Famema).

Herpes simplex virus 1 and cytomegalovirus are associated with pemphigus vulgaris but not with pemphigus foliaceus disease

Pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are blistering autoimmune diseases that depend on interaction between genetic and environmental factors. Viral infections, like herpes simplex viruses 1 and 2 (HSV1/2), cytomegalovirus (CMV), Epstein-Barr virus and dengue virus, could trigger or exacerbate pemphigus. IgM and IgG antibodies against these viruses in serum from PV and PF, their relatives and controls were determined. HSV1/2 expression was evaluated by direct immunofluorescence (DIF) and qPCR in affected or not oral mucosa from PV patients compared with uninjured PF mucosa. IgG anti-HSV1 was higher in the PV group compared with all groups. IgG anti-CMV resulted higher in PV group compared with PF patients and PV relatives. HSV1 was confirmed by DIF and qPCR on oral samples from patients with PV. Lack of HSV1 expression in the oral mucosa of patients with PF corroborate that immunosuppressive therapy cannot be the main cause for HSV1 replication in PV disease.

Differential HLA class I and class II associations in pemphigus foliaceus and pemphigus vulgaris patients from a prevalent Southeastern Brazilian region

Genetic factors, particularly those concerning HLA class II, have been associated with the pathogenesis of pemphigus. Taking advantage of an area where pemphigus foliaceus (PF) and pemphigus vulgaris (PV) are prevalent in the northeastern region of the state of São Paulo, Southeastern Brazil, we have studied the HLA class I (A, B and C) and class II (DRB1 and DQA1/DQB1) profiles in 86 and 83 patients with PF and PV, respectively, as compared with 1592 controls from the same region. Among all the HLA alleles described herein, the more prevalent susceptibility alleles for PF were HLA-A*11, 33, -B*14; -DRB1*01:01, *01:02; -DQA1*01:02; and -DQB1*05:01. In PV patients, the HLA-B*38; -C*12; -DRB1*04:02, *08:04, *14:01, *14:04; -DQA1*03:01; and -DQB1*03:02 and *05:03 alleles were associated with susceptibility. The HLA-DRB1*01:02 allele and the HLA-DRB1*01-DQA1*01-DQB1*05 haplotype in PF patients and the HLA-DRB1*04:02 and *14:01 alleles and the HLA-DRB1*14-DQA1*01-DQB1*05 haplotype in PV patients were related with the highest etiologic fraction values. Distinct genetic patterns and not yet described HLA susceptibility/protection alleles/haplotypes profiles have been observed in this series. Our findings corroborate the differential genetic markers in PF and PV in an area where pemphigus is prevalent but not yet reported.

Localized pemphigus foliaceus with unilateral facial involvement

Pemphigus foliaceus is a superficial vesiculobullous disease that typically presents with widespread lesions. Localized presentations are less frequent, and they typically occur in middle-aged patients, following exposure to topical medications, and later on, become more disseminated. We present a case of a 19-year-old female with a localized presentation of pemphigus foliaceus unrelated to previous topical medications, that was a diagnostic and therapeutically challenging case. We also discuss the literature on localized cases, differences in presentations and responses to various treatment modalities.

Prevalence of Metabolic Syndrome and its components in a Brazilian sample of pemphigus patients

BACKGROUND

Pemphigus foliaceus and pemphigus vulgaris are endemic in the northeastern region of São Paulo State, Brazil. They are treated mainly with systemic corticosteroids, which may provoke osteoporosis; atherosclerosis, higher blood pressure, insulin resistance, glucose intolerance, hyperlipidemia and abdominal obesity. These side effects of corticoids also constitute criteria for the diagnosis of metabolic syndrome.

OBJECTIVE

The prevalence of metabolic syndrome and each component of metabolic syndrome in Pemphigus foliaceus and pemphigus vulgaris groups was compared with Brazilian casuistic samples.

METHODS

Data of 147 patients (pemphigus foliaceus 48.9% and pemphigus vulgaris 51.1%) were compiled from medical records regarding metabolic syndrome and its components, and included in the analysis.

RESULTS

There was no significant difference regarding the prevalence of metabolic syndrome in pemphigus groups compared with the Brazilian casuistic samples. The analysis of each component of metabolic syndrome showed a higher prevalence of: higher blood pressure in male subjects with pemphigus vulgaris, and in pemphigus foliaceus in both genders; diabetes mellitus in both genders for pemphigus vulgaris and pemphigus foliaceus; obesity in females for pemphigus vulgaris and pemphigus foliaceus, and hypertriglyceridemia in both genders for pemphigus vulgaris and pemphigus foliaceus groups that were statistically significant compared to the Brazilian reports. Furthermore, the study noted a higher incidence of cardiovascular events in both genders in pemphigus foliaceus and pemphigus vulgaris groups than in Brazilian casuistic samples.

CONCLUSION

The components of metabolic syndrome are more numerous in pemphigus when compared with Brazilian casuistic samples. Future studies are necessary to assure that metabolic syndrome may be associated with pemphigus per se, including a greater casuistic sample of patients who have not taken corticoids.

IgG autoantibody response against keratinocyte cadherins in endemic pemphigus foliaceus (fogo selvagem)

It is well established that autoantibodies against desmoglein 3 and desmoglein 1 (Dsg1) are relevant in the pathogenesis of pemphigus vulgaris and pemphigus foliaceus, including its endemic form fogo selvagem (FS). Isolated reports have shown that in certain patients with these diseases, autoantibodies against other desmosomal cadherins and E-cadherin may also be present. The goal of this investigation was to determine whether FS patients and normal individuals living in endemic areas possess autoantibodies against other desmosomal cadherins and E-cadherin. By testing a large number of FS and endemic control sera by ELISA, we found a consistent and specific autoantibody response against Dsg1 and other keratinocyte cadherins in these individuals, which is quite different from healthy individuals from the United States (US controls). Overall, the highest correlations among the autoantibody responses tested were in the endemic controls, followed by FS patients, and lowest in the US controls. These findings suggest that multiple, perhaps cross-reactive, keratinocyte cadherins are recognized by FS patients and endemic controls.