Citations

AbstractIgA vasculitis is a small‐vessel vasculitis subtype with increased risk of systemic involvement. We aimed to investigate if any light‐microscopic features can predict the presence of perivascular granular IgA deposits on direct immunofluorescence (DIF) microscopy. We performed a retrospective search of cutaneous pathology reports from our internal and consultation practice (January 1, 2010–October 5, 2021) with a diagnosis of leukocytoclastic vasculitis and accompanying DIF. A blinded dermatopathologist reviewed standard microscopy slides for predetermined histopathological features. Fifty‐six biopsies (48 patients) and 56 biopsies (42 patients) met inclusion criteria for IgA+ and IgA−, respectively. The presence of eosinophils and mid and deep dermal inflammation were statistically more associated with IgA− (41/56 [73.2%] and 31/56 [55.4%], respectively) than IgA+ cases (28/56 [50.0%] and 14/56 [25.0%]; p = 0.049 and 0.006, respectively, chi‐squared test). Other microscopic criteria recorded were not significantly different between the two groups (p > 0.05, chi‐squared and Fisher's exact tests). In this retrospective study of 112 cases, we found that while the absence of eosinophils and absence of mid‐ and deep inflammation were correlated with increased likelihood of IgA perivascular deposition on DIF, no other histopathological features on light microscopy tested could reliably predict the presence of IgA perivascular deposition on DIF. Therefore, DIF remains a necessary component for the accurate diagnosis of cutaneous IgA vasculitis.

AbstractBackgroundVEXAS (vacuoles, E1 enzyme, X‐linked, autoinflammatory, somatic) syndrome is an autoinflammatory disease with frequent cutaneous manifestations.MethodsWe conducted a retrospective study of all patients with genetically confirmed VEXAS syndrome seen at our institution. Available clinical photographs and skin biopsy slides were reviewed.ResultsCutaneous manifestations developed in 22/25 (88%) patients with VEXAS syndrome. From this group, 10/22 (45%) developed skin involvement before or at the time of other clinical features of VEXAS. Twenty distinct dermatologic presentations of VEXAS from 14 patients were reviewed, and histopathologic patterns were classified as follows: neutrophilic urticarial dermatosis (n = 5, 25%), leukocytoclastic/urticarial vasculitis (n = 4, 20%), urticarial tissue reaction (n = 4, 20%), neutrophilic dermatosis (n = 3, 15%), neutrophilic panniculitis (n = 2, 10%), and nonspecific chronic septal panniculitis (n = 2, 10%). Common systemic findings included macrocytic anemia (96%), fever (88%), thrombocytopenia (76%), weight loss (76%), ocular inflammation (64%), pulmonary infiltrates (56%), deep venous thrombosis or pulmonary embolism (52%), and inflammatory arthritis (52%).ConclusionsCutaneous involvement is a common feature of VEXAS syndrome, and histopathologic findings exist on a spectrum of neutrophilic inflammatory dermatoses.

Abstract Acute graft-versus-host disease (GVHD), a serious complication of allogeneic hematopoietic cell transplantation (HCT), frequently involves the skin. Since clinicopathologic features of GVHD can mimic those of certain drug eruptions, accurate diagnosis can be challenging. We aimed to develop a tissue-based molecular assay to improve differentiation of GVHD from vacuolar interface drug eruption in the post-HCT period. After identifying 62 putative tissue-based biomarkers using unbiased molecular methods, we incorporated 26 into a quantitative RT-PCR assay. We tested skin biopsy specimens showing vacuolar interface changes attributable to either acute GVHD (n=67) or drug reaction (n=17), as classified by meticulous review of clinical features and course. Data were incorporated into clinical-molecular fusion diagnostic models. Significant differences in the expression of several genes, including MX1, MNDA, OAS, LIMA1, GSTM5, and SPP1, were detected between the two diagnostic groups (p<0.05). The optimal fusion model, which incorporated quantitative expression of MX1, MNDA, OAS, and GSTM5, as well as the clinical feature of diarrhea, imparted high diagnostic accuracy (receiver operating characteristic area-under-curve: 0.89). This novel tissue-based diagnostic molecular assay and fusion model demonstrates potential to improve distinction of GVHD from drug eruptions in the post-HCT setting. Multicenter validation studies are required.

AbstractOral lichen planus (OLP) confers an approximately 1% risk of transformation to oral squamous cell carcinoma (OSCC). Early identification of high‐risk OLP would be very helpful for optimal patient management. We aimed to discover specific tissue‐based protein biomarkers in patients with OLP who developed OSCC compared to those who did not. We used laser capture microdissection– and nanoLC–tandem mass spectrometry to assess protein expression in fixed lesional mucosal specimens in patients with indolent OLP (no OSCC after at least 5‐year follow‐up, n = 6), transforming OLP (non‐dysplastic epithelium with lichenoid inflammation marginal to OSCC, n = 6) or normal oral mucosa (NOM, n = 5). Transforming OLP protein profile was enriched for actin cytoskeleton, mitochondrial dysfunction and oxidative phosphorylation pathways. CA1, TNNT3, SYNM and MB were overexpressed, and FBLN1 was underexpressed in transforming OLP compared with indolent OLP. Integrin signalling and antigen presentation pathways were enriched in both indolent and transforming OLP compared with NOM. This proteomic study provides potential biomarkers, such as CA1 overexpression, for higher‐risk OLP. While further validation studies are needed, we propose that epithelial–mesenchymal transition may be involved in OLP carcinogenesis.

AbstractBackground/ObjectivesPediatric lichen planus (LP) is rare with variable prevalence and atypical presentations compared to adults. Data on LP are lacking for the pediatric population in the United States. We present demographics, presentations, and treatments for a pediatric LP cohort.MethodsWe reviewed 26 patients diagnosed with LP at 20 years or younger. Treatment responses were defined as no response, partial response, and complete response.ResultsDemographics included 54% females and median diagnosis age of 16 years (range 6–20). Most patients presented with cutaneous LP (65%), with fewer having associated oral (23%), nail (7.7%), or genital (3.8%) involvement. Some had cutaneous‐only LP (38%) or strictly mucosal LP (oral‐only 19% and genital‐only 15%). LP lesions were pruritic (50%), painful (19%), and/or asymptomatic (35%). Complete/partial responses occurred with medium‐potency topical corticosteroids in cutaneous (n = 7; 64%), oral (n = 3; 75%), and genital LP (n = 3; 100%), with high/ultra‐high potency topical corticosteroids in oral LP (n = 6; 86%), and with topical calcineurin inhibitors in genital LP (n = 2; 100%). Side effects were clobetasol‐related oral candidiasis and biopsy‐related penile depressed scar. Most patients with available follow‐up achieved remission (n = 17; 81%).ConclusionsPediatric LP usually presents in adolescence with cutaneous involvement and is symptomatic. However, patients frequently can have oral, genital, or nail lesions or may be asymptomatic, so they need thorough examinations and follow‐up. Long‐term remission is common due to treatment or natural disease course. Medium‐potency corticosteroids are recommended for cutaneous, oral, and genital LP. Various other local and systemic therapies exist with successful treatment responses.

Abstract Background Pemphigoid gestationis (PG) and polymorphic eruption of pregnancy (PEP) are pregnancy‐related dermatoses. Definitive diagnosis often relies upon histopathology and direct immunofluorescence (DIF). PG is associated with fetal and neonatal risks, while PEP confers minimal risk. Objective We aimed to compare histopathologic features to determine key differentiators. Methods A retrospective cohort study of PG and PEP cases, with accompanying DIF, conducted from 1995 to 2020. Skin biopsies were examined independently in a blinded fashion by two dermatopathologists for a list of histopathological features. Results Twenty‐one cases of PG and 10 cases of PEP were identified. PG had significantly denser eosinophils than PEP (mean 155 vs. 48 cells/5 hpf; p < 0.018). PG was also noted to have eosinophilic spongiosis and eosinophils at the dermal–epidermal junction more frequently compared to PEP (80% PG vs. 10% PEP; p < 0.001). A mean cutoff value of 86 eosinophils and a mean optimal sensitivity and specificity of 81% and 83%, respectively, for eosinophils density's diagnostic power of PEP versus PG were achieved. Subepithelial separation was exclusively seen in PG (40% vs. 0%; p < 0.007). Conclusion Eosinophilic spongiosis, eosinophilic epitheliotropism, and dense superficial dermal eosinophils were diagnostic of PG. Given overlapping clinicopathologic features, however, DIF results with clinicopathologic correlation, remain the gold standard.

AbstractVulvar lichen sclerosus (VLS) confers approximately 3% risk of malignant transformation to vulvar squamous cell carcinoma (VSCC). We used unbiased proteomic methods to identify differentially expressed proteins in tissue of patients with VLS who developed VSCC compared to those who did not. We used laser capture microdissection‐ and nanoLC‐tandem mass spectrometry to assess protein expression in individuals in normal vulvar tissue (NVT, n = 4), indolent VLS (no VSCC after at least 5 years follow‐up, n = 5) or transforming VSCC (preceding VSCC, n = 5). Interferon‐γ and antigen‐presenting pathways are overexpressed in indolent and transforming VLS compared to NVT. There was differential expression of malignancy‐related proteins in transforming VLS compared to indolent VLS (CAV1 overexpression, AKAP12 underexpression), particularly in the EIF2 translation pathway, which has been previously implicated in carcinogenesis. Results of this study provide additional molecular evidence supporting the concept that VLS is a risk factor for VSCC and highlights possible future biomarkers and/or therapeutic targets.

AbstractLafora disease is a rare inherited neurodegenerative disease with onset in adolescence. Patients present with progressive myoclonic seizures and cognitive decline. The disease is linked to mutations in either of the two genes encoding malin and laforin, and it is associated with the accumulation of polyglucosan inclusions (Lafora bodies [LBs]) in various tissues, such as brain, liver, muscle, and skin, with the skin being particularly accessible for biopsy. Histopathologic examination of affected tissue with demonstration of LBs, together with the presence of pathologic mutation in EPM2A or NHLRC1 genes, is sufficient for diagnosis of this neurologic disorder when clinically suspected. Here, we report the case of a 16‐year‐old female with progressive neurologic symptoms and homozygous mutation in the NHLRC1 gene encoding malin. The skin biopsy was instrumental in reaching the final diagnosis by showing LBs in sweat glands by histopathologic and electron microscopic examination.

AbstractBackgroundOral lichen planus (OLP), a World Health Organization (WHO)‐classified oral potentially malignant condition, confers a 1% risk of transformation to oral squamous cell carcinoma (OSCC). There does not appear to be a consensus understanding of the underlying molecular events. This scoping review aimed to identify critical molecular pathways and highlight gaps in existing knowledge on malignant transformation in OLP.MethodsFollowing Preferred Reporting Items for Systematic Reviews and Meta‐Analysis Protocols (PRISMA‐P) guidelines, a comprehensive literature search and methodical screening identified 61 relevant studies detailing molecular differences between OLP and OSCC.ResultsMolecular changes shared between OLP and OSCC included those affecting cellular proliferation (altered p53 expression, hypermethylation of p16/CDKN2A, MYC gains, increased ki‐67), apoptosis (increased bcl‐2 and survivin expression), extracellular matrix (ECM) remodeling (increased matrix metalloproteinase [MMP] expression), and transcriptional control (altered bmi1 and microRNA [miRNA] expression). In addition, some molecular alterations accumulated incrementally from control to OLP to OSCC or were present in higher‐risk erosive variants of OLP or transformed OLP. Few studies included rigorous diagnostic inclusion criteria or unbiased discovery methods.ConclusionsResults of this review support the potentially malignant nature of OLP and imply that molecular events associated with malignant transformation may be heterogeneous. In addition, findings in this review highlight the need for additional studies using rigorous diagnostic inclusion criteria and unbiased discovery methods to further understand this process.