Rete Ridges Research Articles

Hypertrophic lichenoid dermatitis immune‐related adverse event during combined immune checkpoint and exportin inhibitor therapy: A diagnostic pitfall for superficially invasive squamous cell carcinoma

Immune checkpoint inhibitors (ICIs) for cancer treatment have revolutionized the field of medicine. However, an unintended but frequent consequence of ICI therapy is the development of cutaneous immune-related adverse events (irAEs), such as lichenoid dermatitis irAEs (LD-irAEs). The hypertrophic variant of LD-irAE may be a diagnostic challenge since it can mimic superficially invasive squamous cell carcinoma (SCC). A 79-year-old woman with metastatic melanoma who began treatment with an ICI-pembrolizumab-plus exportin-1 (XPO1) inhibitor presented after 1 month of therapy with symmetrical violaceous papules coalescing into plaques and with two nodules of the bilateral dorsal hands. Biopsy of the nodules revealed an actinic keratosis and atypical epidermal proliferation concerning for SCC. However, in the ensuing 3 weeks, the patient developed multiple new erythematous, violaceous, and scaly macules and papules, some coalescing into plaques on the extremities. Biopsies of these lesions revealed exuberant irregular epidermal hyperplasia with hypermaturation and lichenoid infiltrate concentrated at the base of the elongated, broadened rete ridges, consistent with hypertrophic LD-irAE. Treatment included topical fluocinonide ointment, intralesional triamcinolone injections and oral acitretin. Distinguishing hypertrophic LD-irAE and SCC can be challenging since both entities share histopathologic features; thus, correlation with clinical presentation is essential for diagnosis and optimal patient management.

Inflammatory features and rete ridge patterns of facial solar lentigo may guide laser treatment.

Relatively little is known about the clinicopathological characteristics of solar lentigo (SL), rendering the choice of laser treatment a clinical challenge. This study compared the clinicohistopathological characteristics of patients with SL on the face with and without conspicuous inflammation. The medical records were evaluated to determine the clinical and histopathological characteristics. Based on the degree of histopathologically observed inflammation, the patients were divided into two groups, those with inflammatory and noninflammatory SL. The demographic characteristics of patients in the inflammatory (n = 62, 62.6%) and noninflammatory groups (n = 37, 37.4%) did not differ significantly. Lesion duration was shorter, and the proportion of patients whose lesions changed within 6 months was higher in the inflammatory than in the noninflammatory group. The mean longest lesion diameter was greater in the inflammatory than in the noninflammatory group. Histopathologically, epidermis was thicker in the inflammatory than in the noninflammatory group. The grade of basal hyperpigmentation was higher in the noninflammatory group, whereas telangiectasia was more frequent in the inflammatory group. The treatment response rate was lower in the inflammatory (7/21, 33.3%) than in the noninflammatory group (8/10, 80.0%). Optimal laser treatment strategies may differ in these two groups.

EVALUATION OF CASES OF EXOPHYTIC VERRUCOUS HYPERPLASIA IN ORAL SUBMUCOUS FIBROSIS IN BIHAR

Verrucous hyperplasia probably represents a morphological variant of verrucous carcinoma by Slootwage J P and Muller H (1983). An essential feature in distinguishing verrucous hyperplasia from verrucous carcinoma is the location of the thickened epithelium with respect to adjacent normal appearing epithelium. In verrucous hyperplasia most of the hyperplastic broadened rete ridges lay above the adjacent normal epithelium while verrucous carcinoma on contrary exhibits a downward growth pattern of otherwise similar rete ridges. Hence based on above findings the present study was planned in Evaluation of Cases of Exophytic Verrucous Hyperplasia in Oral Submucous Fibrosis in Bihar.
 The present study was planned in Department of Dentistry, netaji subhash Medical College & Hospital, Bihta, Patna, Bihar. Conventional oral examination (COE) of 30 patients with Oral submucous fibrosis (OSMF) was performed using incandescent operatory light. Out of that 6 cases having Verrucopapillary lesion were evaluated in the present study.
 The data generated from the present study concluded that patients with highly suspicious malignant verrucous growths on VEL scope examination exhibited increased auto fluorescence and on histopathological examination revealed no signs of dysplasia or invasion. Exhibition of increased autofluorescence of these lesions on VELscope examination could greatly help to determine their nondysplastic nature.
 Keywords: Verrucous hyperplasia, Verrucous carcinoma, Oral Submucous Fibrosis, etc.

Development of Feasible Methods to Image the Eyelid Margin Using In Vivo Confocal Microscopy.

To develop a feasible method to image eyelid margin structures using in vivo confocal microscopy (IVCM) for use in clinical research. Second, to assess the association between IVCM and meibography images. IVCM was performed on the central upper eyelid margin of 13 healthy participants (31 ± 5 years). Overall morphology montages (1600 × 1600 μm) were created of 3 participants. Single frames (400 × 400 μm) of 10 participants were imaged to determine the feasibility of measuring eyelid features. Meibography was performed with EASYTEARview+ in the same 10 participants. ImageJ software was used to quantify image structures. In the montages, structures of rete ridges, meibomian gland openings, and the lid wiper region were observed. The maximum possible montage size, using multiple single frames, was approximately 5200 × 1500 × 150 μm in the X, Y, and Z directions, respectively. The mean number, density, area, perimeter, and shortest and longest diameters of rete ridges of the 9 nonoverlapped frames were 12 ± 2/frame, 73 ± 5/mm, 2504 ± 403 μm, 250 ± 33 μm, 40 ± 6 μm, and 84 ± 13 μm, respectively. Sampling analysis determined at least 5 nonoverlapped frames were necessary to accurately represent the parameters of the ridges. The mean areas of 3 meibomian openings were 785 ± 784 μm, 1036 ± 963 μm, 950 ± 1071 μm, 848 ± 954 μm, 737 ± 831 μm, 735 ± 743 μm, and from 30 μm to 130 μm at 20-μm depth intervals, respectively. No significant association between IVCM and meibography parameters (P = 0.53) was found. Imaging rete ridges with IVCM should include at least 5 nonoverlapping single frames in the upper eyelid margin. At least 3 openings imaged between 30 and 130 μm at 20-μm depth intervals are recommended to determine the opening area.

Expression of transforming growth factor beta in oral submucous fibrosis

BackgroundOral submucous fibrosis (OSMF) is a premalignant condition mainly caused by areca nut chewing and is characterized by progressive fibrosis of submucosal tissues and epithelial atrophy. Activation of transforming growth factor beta (TGF-β) signaling is considered main causative event for increased collagen production and fibrosis. In this study, molecular pathogenesis of OSMF was investigated based on the expression of the TGF-β genes in OSMF tissues compared to normal controls. MethodsA total of 33 OSMF and 10 normal tissues were collected from patients and their clinic-epidemiological data was recorded. The expression of TGF-β isoform genes- TGF β1, TGF β2, TGF β3 and its receptor TGF βR1, TGF βR2 was studied by real time polymerase chain reaction (PCR). Comparison of the expression of these genes among normal controls and OSMF patients was done. The PCR results were confirmed by histopathological and immunohistochemical staining. ResultsThe histological changes included atrophic epithelium, loss of rete ridges, presence of inflammatory cells and dense collagen bundles in connective tissue. PCR showed statistically significant upregulation of TGF-β isoforms in OSMF as compared to normal tissues. Of the three isoforms, maximum fold change was observed in TGF-β1. Similarly, both TGF-βR1 and TGF-βR2 were found to be elevated in OSMF tissues compared to normal. The semi-quantitative analysis by immunohistochemical staining revealed statistically significant difference between normal and OSMF tissues. ConclusionTGF-β signaling plays a major role in the molecular pathogenesis of OSMF as shown by increased mRNA expression of all the three TGF-β isotypes and their receptors.

Benign Alveolar Ridge Keratosis: Clinical and Histopathologic Analysis of 167 Cases.

Benign alveolar ridge keratosis (BARK), the intraoral counterpart of cutaneous lichen simplex chronicus, is a reactive hyperkeratosis caused by trauma or friction that presents as a poorly demarcated white papule or plaque on the keratinized mucosa of the retromolar pad or alveolar ridge mucosa (often edentulous). This is a clinical and histopathologic analysis of BARK including evaluation of p53 expression in selected cases. One hundred and sixty-seven cases of BARK were identified from 2016 to 2017 and 112 (67.1%) occurred in males with a median age of 56years (range 15-86). The retromolar pad was affected in 107 (64.1%) cases and the edentulous alveolar mucosa in 60 (35.9%) cases, with 17.4% of the cases presenting bilaterally. BARK showed hyperkeratosis often with wedge-shaped hypergranulosis and occasional focal parakeratosis. The epithelium exhibited acanthosis and surface corrugation with tapered rete ridges often interconnected at the tips. The study for p53 performed in 12 cases showed less than 25% nuclear positivity. BARK is a distinct benign clinicopathologic entity caused by friction, which should be clearly distinguished from true leukoplakia, a potentially malignant disorder.

Accelerated chronic skin changes without allograft vasculopathy: A 10-year outcome report after face transplantation

BackgroundLong-term outcomes after face transplantation are rarely reported in the scientific literature. Here we present outcome data of a partial face allograft recipient 10 years after transplantation. MethodsMedical records were reviewed for functional and psychosocial outcomes as well as complications. Histopathologic analyses of autopsy tissues and characterization of skin immune cells were performed. ResultsThe patient retained long-term motor and sensory function, though with a noticeable drop in sensory function after year 5. Social reintegration of the patient was marked by reconnection with his family and participation in public social activities. Immunosuppressive therapy consisted of tacrolimus (target levels 6–8 ng/mL after the first year), mycophenolate, and prednisone, while steroids were completely weaned between years 1 and 7. One acute cellular rejection episode of grade II or higher occurred on average per year and led to chronic skin changes (papillary dermal sclerosis with superficial hyalinization, epidermal thinning with loss of rete ridges, perieccrine fibrosis), but the allograft vessels, muscles, adipose tissue, and bone were spared. Allograft skin was characterized by increased number of CD4+ TNF-α/IL17A producing T-cells as compared with native skin. Long-term kidney function was maintained at 60 mL/min estimated glomerular filtration rate. Unfortunately, the preexisting hepatitis C virus infection with liver cirrhosis was resistant to 3 treatments with new direct-acting antivirals and eventually hepatocellular carcinoma developed, causing the patient’s death 10 years after transplantation. ConclusionThis report suggests that face transplants can maintain their function for at least 10 years. Chronic skin changes can occur independently of allograft vasculopathy.

Multiple oral verruciform xanthomas: A rare entity

Verruciform xanthoma (VX) is an uncommon benign lesion that can affect oral, genital mucosa, and rarely skin. The characteristic foam cells seen in papillary dermis are a hallmark for diagnosing this entity. A 42-year-old male, tobacco-chewer presented with asymptomatic white-circular plaques on the bilateral buccal mucosa and yellow papules on retromolar area which on histopathological evaluation showed parakeratotic epithelium with surface and deep invagination of columns of parakeratosis throughout the hyperplastic epidermis, few neutrophils in upper spinous layers, and uniform elongation of rete ridges. The rete ridges showed numerous lipid-laden CD 68-positive foam cells. Punch excision coupled with cryotherapy was done, which resulted in the complete resolution of lesions. We publish this uncommon benign entity for increased awareness among physicians to consider it as a differential of verrucous lesion in the mucosa. Our patient had two different morphology of lesions, both suggestive of VX with characteristic foam cells on histopathology.

Gas chromatography-mass spectrometry elucidation and antipsoriatic activity on developed herbal formulations from Carissa congesta, Catharanthus roseus, Annona squamosa, and Polyalthia longifolia Plant Extracts

Background: Annonaceae and Apocynaceae families are known for their plethora of pharmacotherapeutic potential. Objectives: To evaluate antipsoriatic potential (ultraviolet [UV]-induced photodermatitis and tail model) and gas chromatography-mass spectrometry (GC-MS) studies on developed formulations from the plant extracts. Materials and Methods: Formulations of ethanolic extracts of Carissa congesta and Catharanthus roseus and petroleum ether extracts of Annona squamosa and Polyalthia longifolia were evaluated for antipsoriatic activity (UV-induced photodermatitis and tail model) at 250 and 500 mg/kg. GC-MS studies were done subsequently after 6 months. Formulation batches were tested by different tests, viz., pH, viscosity, spreadability, washability, homogeneity, grittiness, drug content, Sudan red, bleeding, and sensitivity tests. Results: Histopathology studies indicated the absence of Munro's microabscess, regular elongation of rete ridges, capillary loop dilatation, granular cell layer, and prominent parakeratosis at 500 mg/kg. Formulations of the plant extracts did not reveal toxic components by GC-MS interpretation. No greasiness was observed during washing. Uniform homogeneity was observed with neither clumps nor large aggregates. The dispersed globules appeared red against colorless water background. Bleeding time was found to be stable during the experimentation.Conclusion: Developed topical plant formulations showed antipsoriatic potential on selected models. The GC-MS studies confirmed the presence of no drastic changes in the quantity of active constituents assuring its stability.

A Case of Pseudoepitheliomatous Keratotic and Micaceous Balanitis with Verrucous Carcinoma

Pseudoepitheliomatous Keratotic and Micaceous Balanitis (PKMB) is a rare chronic inflammatory disease characterised by hardened, hyperkeratotic plaques on the glans of the penis of older men. Although PKMB is described as benign, there is growing evidence that it has the potential to become cancerous. authors hereby report a case of 55 year old male who was initially characterised by white sclerosis and atrophy at the glans. Without treatment, verrucous keratinising organisms appeared after two years and were misdiagnosed as viral warts. The patient received four cryotherapy treatment with liquid nitrogen, which completely removed the warts, but the rash recurred about two months after cryotherapy. The patient received histopathological examinations which showed obvious hyperkeratosis with incomplete keratosis in the epidermis, papilloma-like and pseudoepithelioma-like hyperplasia appeared in the spinous layer, flattening of rete ridges, squeezing growth into the dermis, disordered arrangement of basal cells and frequent mitoses. A few squamous masses were seen in the dermis and the formation of squamous fossa could be seen.There were more lymphocyte infiltrations in the superficial layer of the dermis and around blood vessels. After being diagnosed with PKMB with verrucous carcinoma, the patient finally chose to undergo surgery in the Urology Department of another hospital. Unfortunately, we lost the follow-up. Our case supports the view that PKMB can develop into a malignant disease, which suggests that early detection, treatment and follow-up of the disease are essential.

Lichen Striatus With Nail Involvement: Two Case Reports

Abstract Introduction: Lichen striatus (LS) is a benign, self-limiting, linear inflammatory skin disease that was rarely reported. Here we report two cases of nail involvement in children with LS. Case presentation: Two children was referred to our hospital with asymptomatic linear eruption and nail dystrophy. Histopathological examination revealed epidermal hyperkeratosis, infiltration of inflammatory cells around the adnexal region, hyperpigmentation in the rete ridges, and focal liquefactive degeneration of the basal layer. Discussion: There is no specific treatment for nail LS. Without treatment, LS can resolve spontaneously over a period of time. Topical steroid treatment can improve symptoms and shorten the duration of the disease. It is important for clinicians to distinguish LS from other linear diseases, which may lead to unnecessary treatment and surgical intervention. Conclusion: The appearance of nail and skin lesions is importance of clinical features in making the diagnosis of nail LS, and also distinguish to other linear and nail diseases.

HECK DISEASE IN A 7-YEAR-OLD AMAZONIC BOY: A CASE REPORT

A 7-year-old male patient was referred to a dentistry specialty center because of several papillary lesions of the same color as the surrounding mucosa, which were painless and nonbleeding in the inner cheek and labial mucosa. The diagnosis hypothesis was multifocal epithelial hyperplasia (Heck disease). An incisional biopsy was performed, and the histopathologic findings in stratified squamous epithelium were parakeratosis, acanthosis, and thick epithelial rete ridges, sometimes being club-shaped. The epithelial cells presented nuclei surrounded by clear halos, mitotic figures, and mitosoid cells. The underlying connective tissue presented scarce inflammatory cells. The data confirmed the original clinical hypothesis of multifocal epithelial hyperplasia (Heck disease). No treatment was performed because of the self-limited characteristics of the disease. The patient is now under 6-month follow-up, already showing early signs of lesion remission.

Fractional CO2 laser micropatterning of cell-seeded electrospun collagen scaffolds enables rete ridge formation in 3D engineered skin

Rete ridges are interdigitations of the epidermis and dermis of the skin that play multiple roles in homeostasis, including enhancing adhesion via increased contact area and acting as niches for epidermal stem cells. These structures, however, are generally absent from engineered skin (ES). To develop ES with rete ridges, human fibroblast-seeded dermal templates were treated with a fractional CO2 laser, creating consistently spaced wells at the surface. Constructs with and without laser treatment were seeded with keratinocytes, cultured for 10 days, and grafted onto athymic mice for four weeks. Rete-ridge like structures were observed in the laser-patterned (ridged) samples at the time of grafting and were maintained in vivo. Ridged grafts displayed improved barrier function over non-lasered (flat) grafts at the time of grafting and 4 weeks post-grafting. Presence of ridges in vivo corresponded with increased keratinocyte proliferation, epidermal area, and basement membrane length. These results suggest that this method can be utilized to develop engineered skin grafts with rete ridges, that the ridge pattern is stable for at least 4 weeks post-grafting, and that the presence of these ridges enhances epidermal proliferation and establishment of barrier function. Statement of significanceRete ridges play a role in epidermal homeostasis, enhance epidermal-dermal adhesion and act as niches for epidermal stem cells. Despite their role in skin function, these structures are not directly engineered into synthetic skin. A new method to rapidly and reproducibly generate rete ridges in engineered skin was developed using fractional CO2 laser ablation. The resulting engineered rete ridges aided in the establishment of epidermal barrier function, basement membrane protein deposition and epidermal regeneration. This new model of engineered skin with rete ridges could be utilized as an in vitro system to study epidermal stem cells, a testbed for pharmaceutical evaluation or translated for clinical use in full-thickness wound repair.

Histopathological Study of Psoriasis and Its Grading According to Trozak Scoring System

Background: Psoriasis is a chronic papulosquamous disorder of undefined etiology, occuring in 0.09 to 11.4% population. Different clinical types occur with varying histopathology. Early and Late onset psoriasis have been defined based on age at presentation. Methods: Cases diagnosed as Psoriasis, both clinically and histologically, were examined for the individual features of Psoriasis. Histomorphological grading of the lesions was also done using the Trozak scoring system. Result: The mean age of the patients was 42.26 with a male predominance (M:F=3.5: 1). Early onset cases constituted 71% of the total cases, while late onset cases were 29%. The histopathological features were found to be variably present. Acanthosis was observed in 96% cases. Hyperkeratosis (94%), parakeratosis (66%), club shaped rete ridges (88%) with regular elongation of rete ridges (72%) with, suprapapillary plate thinning (74%), hypogranulosis (72%), elongation and edema of dermal papillae (88%) were other features seen in majority of cases. Perivascular mononuclear infiltrate in upper dermis of papillae (76%), dermal (76%) and epidermal (78%) neutrophils, spongiform pustules of Kogoj (24%), Munro’s microabscess (28%), were the inflammatory changes observed, present to a greater extent in the early onset cases than the late onset cases. The Trozak scoring system gave an average score of 9.44, with no significant difference in the early and late onset cases of Psoriasis. Conclusion: Entirely typical histological features are found only in a small percentage of biopsy specimens, even if only clinically typical lesions of psoriasis are examined.

A case of de novo psoriasis induced by atezolizumab in a patient with advanced lung cancer

A 70-year-old Japanese male had de novo psoriasis after the treatment of atezolizumab, anti PD-L1 antibody agent, for lung cancer. The patient was successfully treated with the conventional therapy without discontinuation of the agent. Our case is the second case of atezolizumab-induced psoriasis. Atezolizumab is a humanized monoclonal antiprogrammed death-ligand 1 (PD-L1) antibody that started to be used internationally in 2016. It is indicated as a treatment for inoperable advanced or relapsed nonsmall cell lung cancer (NSCLC). Psoriasis may arise as an immune-related adverse event (irAE), is known to newly appear or be worsened after treatment with antiprogrammed death-1 (PD-1) agents, such as nivolumab.1, 2 However, there have been only a few reports on anti-PD-L1 agent-induced psoriasis.3, 4 Here, we report a case of de novo psoriasis induced by atezolizumab, which was successfully treated with the conventional therapy without discontinuation of atezolizumab. A 70-year-old Japanese male with no history of psoriasis started to receive atezolizumab treatment (1200 mg/body, every 3 weeks) in July 2018 for advanced squamous NSCLC (cT3N1M0, stage IIIA), originating in the left upper lung. He had already received four courses of radiochemotherapy a year before, but had exhibited progressive disease. Pruritic scaly erythematous plaques appeared after the third round of treatment with atezolizumab and rapidly worsened (Figure 1A). Laboratory data were almost normal, except for an elevated serum squamous cell carcinoma (SCC) antigen level (6.0 ng/mL, normal range: ≤2.5 ng/mL), which was regularly measured as a tumor marker of lung cancer. Histopathologically, the lesion exhibited parakeratotic hyperkeratosis, elongated rete ridges, loss of the granular layer, perivascular infiltration of lymphocytes intermingled with eosinophils in the upper dermis, and capillary dilation in the dermal papillae (Figure 1B,C). We diagnosed the patient with de novo psoriasis, triggered by atezolizumab. The patient was treated with calcipotriol/betamethasone dipropionate combination ointment without discontinuation of atezolizumab treatment. The rash gradually improved after the 7th round of treatment, and it had almost disappeared by the 11th round of treatment (Figure 1D). The patient's serum SCC antigen level was changed in parallel with his psoriatic skin activity, peaking (18.1 ng/mL) between the 7th and 8th rounds of treatment. The patient noticed small lesions a couple of days after each treatment. His lung cancer was markedly ameliorated by the fourth round and exhibited a complete response at the time of the 19th round of treatment. The blockade of PD-L1/PD-1 pathways has been demonstrated to augment T helper (Th) 1 and Th17 cell activity.5 This results in increases of various psoriasis-related cytokines, such as interferon -γ, interleukin (IL) -17A, IL-21, IL-22, and IL-6 released from Th1 and Th17 cells.6 Although little is known about which cytokines play an important role in the pathogenesis of anti-PD-1/PD-L1-induced psoriasis, Tanaka et al7 reported that the serum level of IL-6 was increased in nivolumab-associated psoriasis and suggested that IL-6 might be a key cytokine in such irAE. However, it has not yet been clarified why our patient's skin lesions subsided despite continuous atezolizumab treatment. Our case is the fourth reported case of anti-PD-L1-induced psoriasis3, 4 and the second case of atezolizumab-induced psoriasis. Among the previous cases, only our patient had no history of psoriasis and was successfully treated without discontinuation of the causative agent. The authors declare that they have no conflicts of interest.

Efficacy of Sweet Pumpkin in Relieving Contact Dermatitis in Chronically Stressed Rats.

Background:Contact dermatitis (CD) is considered among the common inflammatory skin diseases worldwide. Cucurbita moschata Duchesne has antioxidant, anti-inflammatory, and antidepressant activity beside many other beneficial effects.Objectives:This study aimed to assess the effect of pumpkin fruit extract in treating CD in mice exposed to chronic stress and to explore the mechanism through which pumpkin can relief these changes.Materials and Methods:Thirty male albino rats were divided into three groups (n = 10); the control and two experimental groups that were exposure to chronic unpredictable mild stress for 4 weeks then painting with 1-fluoro-2,4-dinitrofluorobenzene (DNFB) for 3 consecutive days/week for 2 weeks to induce CD. Biochemical assessment of corticosterone level and antioxidants activity was performed. Skin of affected areas was excised, processed for histopathological examination.Results:DNFB-induced CD presented with dryness, hardness, and scaling. There was a significant reduction (P < 0.001) in the levels of superoxide dismutase, glutathione peroxidase and catalase activity in the skin of rats had CD. Histopathologically, the shin showed hyperplastic-thickened epidermis, focal elongation of the rete ridges, inflammatory cells infiltration in the superficial dermis, and increased collagen fibers. Local administration of pumpkin extract significantly increased the antioxidants activity in the skin and alleviated the CD-associated changes.Conclusions:This study showed that the pumpkin fruit extract could have a potential in treating CD in stressed conditions mainly via its enhancement of skin antioxidant activity.

The Influence of Ketogenic Diets on Psoriasiform-Like Skin Inflammation

The Influence of Ketogenic Diets on Psoriasiform-Like Skin Inflammation

Histologic Features of Secondary Syphilis

Background: Secondary syphilis is a sexually transmitted infection, which is referred to as “the great imitator” and has a wide spectrum of clinical manifestations. As a result, it is essential to identify potential secondary syphilis patients with ambiguous clinical manifestation through pathology. Objective: We sought to analyze the pathological features of secondary syphilis. Methods: We analyzed 59 biopsy specimens from 56 patients with secondary syphilis. Cases were classified according to the histological characteristics and clinical features. Results: Necrotic keratinocytes could be observed in 39 of 59 (66.1%) secondary specimens. Plasma cells (86.4%) were the most common finding overall. The presence of Treponema pallidum was detected mostly at the dermal-epidermal junction. There was no statistical significance between pathological features and age, HIV status, or RPR titer. Conclusions: Necrotic keratinocytes are one of the characteristics of secondary syphilis. The combination of plasma cells, irregular acanthosis, elongated rete ridges, and endothelial swelling should increase the likelihood of syphilis.

Mechanical stretching stimulates growth of the basal layer and rete ridges in the epidermis.

We have developed four experimental models of mechanical stimulation applied to the back skin using tissue expansion (TE) procedure performed on minipigs. The technique is used by plastic surgeons for decades, to amend the congenital or accidental skin defects, though underlying changes in epidermis are not well understood. We found that the initial stretching increased proliferation of basal keratinocytes leading to elongation of the basal layer, and increased cellular density. The increased number of the rete ridges, suggests that they absorbed the impact of excessive proliferation, preserving layered organization of epidermis. We found β1 integrin to be a very sensitive responder to stimulation instigated by TE procedure, able to dynamically relocate to adjust the basal cell against external force. Repeated mechanical stimulation with a seven-day interval generated healthy tissue without detrimental effects. Given the similarities between the structure of the porcine and human epidermis, we speculate that a similar mechanism functions in human skin. A better understanding of the underlying process could help improve medical care and outcomes for patients undergoing surgical reconstruction.

The histopathological landscape of the major psoriasiform dermatoses.

Psoriasiform dermatoses represent a wide spectrum of inflammatory conditions, with several major forms represented by psoriasis, as the prototype of this category, followed by pustular psoriasis, Reiter’s syndrome, pityriasis rubra pilaris, lichen simplex chronicus and large-plaques parapsoriasis. They create a diagnostic challenge, both clinical and histopathological, because of their complexity and frequent overlapping of the microscopical features. The characteristic histopathological features of psoriasiform reaction comprise extensive hyperkeratosis, with horizontally confluent but vertically intermittent parakeratosis, which alternate with orthokeratosis, thin granular layer, with relative frequent mitoses, uniform elongated and fused rete ridges, edematous superficial papillary dermis, with dilated capillaries, perivascular lymphocytic infiltrate, Munro’s microabscesses, and spongiform pustules of Kogoj. Our paper aims to review the histopathology of major form of psoriasiform dermatoses and to emphasize the characteristic microscopical differences between them, for a better approach of the diagnosis as an important key for clinical and therapeutical management. Using the clinicopathological correlations, a thoroughly evaluation of the microscopical features and compartments distribution or special stainings and techniques, the range of differential diagnosis can be decreased and a more accurate diagnostic can be usually achieved. The insights into the pathogenic mechanisms can lead to new therapeutic opportunities targeted to the specific type of inflammatory lesion.