The histopathology of psoriasis

Biomarkers in Oral Fluids as Diagnostic Tool for Psoriasis

Psoriasis is a prevalent worldwide chronic immuno-inflammatory skin disease with various variants and atypical cases. The use of biomarkers for the diagnosis of psoriasis can favor timely treatment and thus improve the quality of life of those affected. In general, the search for biomarkers in oral fluids is recommended as it is a non-invasive and fast technique. This narrative review aimed to identify biomarkers in gingival crevicular fluid (GCF) and saliva to diagnose psoriasis. To achieve this goal, we selected the available literature using the following MESH terms: “psoriasis”, “saliva” and “gingival crevicular fluid”. The studies analyzed for this review cover original research articles available in English. We found three full articles available for psoriasis biomarkers in GCF and ten articles available for psoriasis biomarkers in saliva. Studies showed that in the saliva of healthy individuals and those with psoriasis, there were differences in the levels of inflammatory cytokines, immunoglobulin A, and antioxidant biomarkers. In GCF, individuals with psoriasis showed higher levels of S100A8, IL-18 and sE-selectin in comparison to healthy individuals, independent of periodontal status. Despite these findings, more studies are required to determine an adequate panel of biomarkers to use in saliva or GCF for psoriasis.

Progress in the application of reflectance confocal microscopy in dermatology

Reflectance confocal microscopy (RCM) is abbreviated as skin three-dimensional computed tomography, which can help clearly observe the structure of the epidermis and superficial dermis. It is a non-invasive skin disease examination method and provides fast access to real-time, dynamic skin micro-anatomical images. Therefore, RCM is widely used in the clinical diagnosis of skin diseases. For example, the RCM features of vitiligo are as follows: pigment loss or partial pigment loss in the lesion area, loss of the basal layer pigment ring. The RCM findings of Riehl melanosis are as follows: basal cell liquefaction and degeneration. The RCM results for verruca plana show: the Rose-like structure. The characteristics of psoriasis under RCM include: hyperkeratosis, parakeratosis, thickening of the spinous layer, capillary dilatation and hyperaemia, peripheral inflammatory cell infiltration. Epidermal brain-like structure was observed under RCM of seborrheic keratosis. With RCM, image acquisition and preservation of the skin is convenient, and the technique is convenient for comparing the development of lesions during long-term follow-up observation. Therefore, it helps to understand disease development in real time and dynamically and can be used to evaluate the curative effect. In this article, we briefly review the technical principles, diagnostic criteria for RCM application and RCM-related research progress in the diagnosis of pigmentary diseases, inflammatory diseases, skin tumours, and other common skin diseases.

Assessing the severity of psoriasis through multivariate analysis of optical images from non-lesional skin

Patients with psoriasis represent a heterogeneous population with individualized disease expression. Psoriasis can be monitored through gold standard histopathology of biopsy specimens that are painful and permanently scar. A common associated measure is the use of non-invasive assessment of the Psoriasis Area and Severity Index (PASI) or similarly derived clinical assessment based scores. However, heterogeneous manifestations of the disease lead to specific PASI scores being poorly reproducible and not easily associated with clinical severity, complicating the efforts to monitor the disease. To address this issue, we developed a methodology for non-invasive automated assessment of the severity of psoriasis using optical imaging. Our analysis shows that two-photon fluorescence lifetime imaging permits the identification of biomarkers present in both lesional and non-lesional skin that correlate with psoriasis severity. This ability to measure changes in lesional and healthy-appearing skin provides a new pathway for independent monitoring of both the localized and systemic effects of the disease. Non-invasive optical imaging was conducted on lesions and non-lesional (pseudo-control) skin of 33 subjects diagnosed with psoriasis, lesional skin of 7 subjects diagnosed with eczema, and healthy skin of 18 control subjects. Statistical feature extraction was combined with principal component analysis to analyze pairs of two-photon fluorescence lifetime images of stratum basale and stratum granulosum layers of skin. We found that psoriasis is associated with biochemical and structural changes in non-lesional skin that can be assessed using clinically available two-photon fluorescence lifetime microscopy systems.

Super Critical Fluid Extracted Fatty Acids from Withania somnifera Seeds Repair Psoriasis-Like Skin Lesions and Attenuate Pro-Inflammatory Cytokines (TNF-α and IL-6) Release

(1) Background: Withania somnifera Dunal (Ashwagandha) is a widely used medicinal herb in traditional medicinal systems with extensive research on various plant parts. Surprisingly, seeds of W. somnifera have never been investigated for their therapeutic potential. (2) Methods: W. somnifera seeds were extracted for fatty acids (WSSO) using super critical fluid extraction, and was analyzed by gas chromatography. Its therapeutic potential in psoriasis-like skin etiologies was investigated using a 12-O tetradecanoyl phorbol 13-acetate (TPA)-induced psoriatic mouse model. Psoriatic inflammation along with psoriatic lesions and histopathological scores were recorded. WSSO was also tested on murine macrophage (RAW264.7), human epidermoid (A431), and monocytic (THP-1) cells, stimulated with TPA or lipo poly-saccharide (LPS) to induce pro-inflammatory cytokine (IL-6 and TNF-α) release. NFκB promoter activity was also measured by luciferase reporter assay. (3) Results: Topical application of WSSO with concurrent oral doses significantly reduced inflammation-induced edema, and repaired psoriatic lesions and associated histopathological scores. Inhibition of pro-inflammatory cytokines release was observed in WSSO-treated A431 and THP-1 cells, along with reduced NFκB expression. WSSO also inhibited reactive nitrogen species (RNS) in LPS-stimulated RAW264.7 cells. (4) Conclusion: Here we show that the fatty acids from W. somnifera seeds have strong anti-inflammatory properties, along with remarkable therapeutic potential on psoriasis-like skin etiologies.

Resolution of plaque-type psoriasis: what is left behind (and reinitiates the disease)

Psoriasis is a chronic inflammatory skin disease that involves numerous types of immune cells and cytokines resulting in an inflammatory feedback loop and hyperproliferation of the epidermis. A more detailed understanding of the underlying pathophysiology has revolutionized anti-psoriatic treatment and led to the development of various new drugs targeting key inflammatory cytokines such as IL-17A and IL-23. Successfully treated psoriatic lesions often resolve completely, leaving nothing visible to the naked eye. However, such lesions tend to recur within months at the exact same body sites. What is left behind at the cellular and molecular levels that potentially reinitiates psoriasis? Here, we elucidate the cellular and molecular “scar” and its imprints left after clinical resolution of psoriasis treated with anti-TNFα, anti-IL-17, or anti-IL-23 antibodies or phototherapy. Hidden cytokine stores and remaining tissue-resident memory T cells (TRMs) might hold the clue for disease recurrence.

The impact of topical Saint John's Wort (Hypericum perforatum) treatment on tissue tumor necrosis factor-alpha levels in plaque-type psoriasis: A pilot study

Context:

Psoriasis is an inflammatory disorder, formed by inappropriate interaction of T lymphocytes with keratinocytes, and consequent eruption of immune responses. High concentrations of tumor necrosis factor-alpha (TNFα) are found in the skin lesions and plasma of patients with psoriasis. Hypericum perforatum, a phytomedicine that has both anti-inflammatory and antiproliferative properties, has been recently reported to be clinically helpful for improvement of psoriatic lesions.

Aims:

The aim of the present study was to investigate the effects of topical H. perforatum on TNFα levels in psoriatic lesions for possible identification of the mechanism by which Hypericum reduces inflammation and modulates the disease in patients with plaque-type psoriasis.

Settings and Design:

A double-blind, placebo-controlled, pilot study with intraindividual comparison was conducted on twenty patients with mild to moderate plaque-type psoriasis.

Subjects and Methods:

TNFα levels in tissue samples were measured with immunohistochemistry method. Moreover, Psoriasis Area Severity Index (PASI) scores and histological and clinical changes were investigated after topical application of Hypericum extract.

Statistical Analysis Used:

The Wilcoxon signed-rank test was used to evaluate the possible differences between the drug and placebo group.

Results:

TNFα concentrations in dermis (p= 0.025), endothelial cells (p=0.033), and dendrite cells (p=0.014) were significantly reduced in lesions treated with drug and the reduction observed in epidermis was superior to placebo (p=0.046). Results of PASI scores showed that erythema, scaling, and thickness were significantly lower where the ointment had been applied compared to application of placebo (p=0.014, p=0.004, p=0.003, respectively). Moreover, significant improvement in clinical and histological features of treated lesions in comparison with untreated lesions was observed (p < 0.05).

Conclusions:

H. perforatum ointment can help decrease PASI scores and TNFα levels in psoriatic tissue. Its efficacy is probably related to its effect on lowering cytokines including TNFα.

Non-invasive Approaches for the Diagnosis of Autoimmune/Autoinflammatory Skin Diseases-A Focus on Psoriasis and Lupus erythematosus

The traditional diagnostic gold standard for inflammatory skin lesions of unclear etiology is dermato-histopathology. As this approach requires an invasive skin biopsy, biopsy processing and analysis by specialized histologists, it is a resource intensive approach requiring trained healthcare professionals. In many health care settings access to this diagnostic approach can be difficult and outside emergency cases will usually take several weeks. This scenario leads to delayed or inappropriate treatment given to patients. With dramatically increased sensitivity of a range of analysis systems including mass spectrometry, high sensitivity, multiplex ELISA based systems and PCR approaches we are now able to "measure" samples with unprecedented sensitivity and accuracy. Other important developments include the long-term monitoring of parameters using microneedle approaches and the improvement in imaging systems such as optical coherence tomography. In this review we will focus on recent achievements regarding measurements from non-invasive sampling, in particular from plucked hair and skin tape-strips which seem well suited for the diagnosis of lupus erythematosus and psoriatic inflammation, respectively. While these approaches will not replace clinical observation-they can contribute to improved subgroup diagnosis, stratified therapeutic approaches and have great potential for providing molecular and mechanistic insight in to inflammatory skin diseases.

Immunohistochemical study of janus kinase 1/signal transducer and activator of transcription 3 in psoriasis vulgaris

Background: Human JAKs are responsible for generating docking sites for human SSTAT phosphorylation. The role of JAKs in psoriasis pathogenesis has not been clearly explained. Aim: To investigate the role of JAK1 in psoriasis pathogenesis and to assess if this role is mediated through STAT3 or not, through evaluation of their immunohistochemical expression in the skin of psoriatic patients. Methods: This case-control study was carried out on 26 patients presenting with psoriasis vulgaris versus 26 age- and sex-matched apparently healthy volunteers. Psoriasis Area and Severity Index (PASI) scores were used to evaluate psoriasis severity. From all controls and cases (lesional and perilesional), skin biopsies were taken for histopathological and immunohistochemical JAK1 and STAT3 evaluation. Results: There was significant stepwise upregulation of JAK1 from controls to perilesional to lesional psoriatic skin of the patient group in both epidermis and dermis (P≤0.001 for both). Dermal JAK1 H-score was significantly associated with psoriasis severity (P=0.01). STAT3 was significantly overexpressed in lesional psoriatic skin over nonlesional skin (P<0.001). There were significant positive correlations between lesional H-scores for STAT3 and Psoriasis Area and Severity Index scores in epidermis (r=0.63, P<0.001), and in dermis (r=0.47, P=0.04). There was a significant positive correlation between JAK1 and STAT3 expression in epidermal lesional psoriatic skin (r=0.44, P=0.03). Conclusion: JAK1 has a proinflammatory effect in psoriasis pathogenesis, which could be mediated through increasing STAT3 expression in psoriasis. JAK1 and STAT3 tissue expression could be markers of psoriasis severity. JAK1 may be used as a target for immunotherapy in psoriasis-management programs.

Are quantitative histopathologic criteria capable of differentiating psoriasis from chronic dermatitis?

Background

There are overlapping features in histopathologic characteristics of psoriasis and chronic dermatitis, which sometimes make the correct diagnosis difficult.

Objective

The aim of this study was to compare the histopathologic diagnostic features of psoriasis with chronic dermatitis quantitatively.

Patients and methods

In this study, 30 patients with psoriasis and 30 patients with chronic dermatitis were included. Diagnosis of psoriasis or chronic dermatitis was based on clinicopathologic correlation. Photos of histopathologic slides were provided by LABOMED Digital Camera and LABOMED Microscope. Width and length of rete ridges, minimal thickness of suprapapillary plates, thickness of epidermis, thickness of hyperkeratotic layer, and minimal thickness of granular layer were determined using Pixel Pro software on micrometer scale.

Results

Suprapapillary plates and granular layer were significantly thicker in patients with chronic dermatitis compared with patients with psoriasis. The rete ridges were longer and wider, the epidermis was thicker, and the parakeratotic layer was also thicker in patients with psoriasis compared with patients with chronic dermatitis, and the difference between these corresponding parameters in the two groups was statistically significant except for thickness of parakeratotic layer. Moreover, the mean ratio of minimal suprapapillary plate’s thickness to epidermal thickness and the mean ratio of minimal granular layer’s thickness to parakeratotic layer’s thickness were significantly higher in patients with chronic dermatitis compared with those with psoriasis.

Conclusion

Despite overlapping histopathologic features in psoriasis and chronic dermatitis, quantitative histopathologic criteria might be valuable for differentiation of these two conditions. Ratios of minimal suprapapillary plate’s thickness to epidermal thickness and minimal granular layer’s thickness to parakeratotic layer’s thickness can be particularly helpful in this regard.

Geographic tongue and psoriasis: clinical, histopathological, immunohistochemical and genetic correlation - a literature review

Geographic tongue is a chronic, inflammatory, and immune-mediated oral lesion of unknown etiology. It is characterized by serpiginous white areas around the atrophic mucosa, which alternation between activity, remission and reactivation at various locations gave the names benign migratory glossitis and wandering rash of the tongue. Psoriasis is a chronic inflammatory disease with frequent cutaneous involvement and an immunogenetic basis of great importance in clinical practice. The association between geographic tongue and psoriasis has been demonstrated in various studies, based on observation of its fundamental lesions, microscopic similarity between the two conditions and the presence of a common genetic marker, human leukocyte antigen (HLA) HLA-C*06. The difficulty however in accepting the diagnosis of geographic tongue as oral psoriasis is the fact that not all patients with geographic tongue present psoriasis. Some authors believe that the prevalence of geographic tongue would be much greater if psoriatic patients underwent thorough oral examination. This study aimed to develop a literature review performed between 1980 and 2014, in which consultation of theses, dissertations and selected scientific articles were conducted through search in Scielo and Bireme databases, from Medline and Lilacs sources, relating the common characteristics between geographic tongue and psoriasis. We observed that the frequency of oral lesions is relatively common, but to establish a correct diagnosis of oral psoriasis, immunohistochemical and genetic histopathological analyzes are necessary, thus highlighting the importance of oral examination in psoriatic patients and cutaneous examination in patients with geographic tongue.

Vascular Features of Nail Psoriasis Using Dynamic Optical Coherence Tomography

BACKGROUND

Nail psoriasis is a painful and disfiguring nail disease that often leads to invasive biopsies. Dermoscopy of the hyponychium can be useful in the diagnosis showing twisted coiled vessels. Structural features of nail psoriasis have been described with optical coherence tomography (OCT).

OBJECTIVES

To investigate vascular features of nail psoriasis using dynamic OCT.

METHODS

This was an observational, prospective, controlled study in which psoriasis patients with psoriatic nail changes and healthy control patients underwent OCT imaging of the distal nail plate and proximal nail fold. Vertical and horizontal OCT images were analyzed to describe structural and vascular features and to quantify blood flow at depth.

RESULTS

Sixteen psoriatic nails and 16 control nails were included. Psoriatic nails had significantly increased blood flow in the proximal nail fold at depths of 0.72 mm (p = 0.035) and 0.76 mm (p = 0.027). Nail thickness was significantly greater in psoriatic nails compared to control nails (p = 0.0016). Compared to control nails, psoriatic nails had dilated, disorganized blood vessels superficially in the proximal nail fold.

LIMITATIONS

The main limitation of our study is the relatively small sample size.

CONCLUSIONS

OCT can identify structural and vascular features specific to nail psoriasis.