{"title":"Nail Telocytes: Identification, Potential Physiological Function, and Role in Pathology: A Reappraisal of the So-Called Onychofibroblasts/Onychodermis.","authors":"Christophe Perrin","doi":"10.1097/dad.0000000000002704","DOIUrl":"https://doi.org/10.1097/dad.0000000000002704","url":null,"abstract":"Some authors have suggested that the fibroblasts of the nail mesenchyme (onychofibroblasts) can be distinguished from skin fibroblasts by their high expression of CD10. My 2015 study documented the presence of a relatively sparse CD34+/CD10+ dendritic subpopulation in the dermis and hypodermis of the matrix. For some time now, my hypothesis has been that these interstitial dendritic mesenchymal cells of the matrix correspond to telocytes. Telocytes have been described as peculiar interstitial dendritic cells present in the mesenchymal tissue of numerous organs, including the skin, but their presence and characteristics in the nail unit have not been explored. This study was undertaken to more comprehensively investigate the existence and characteristics of nail telocytes. A series of 20 normal adult nail units were examined with a combination of morphological and immunohistochemical analyses. The matrix dermis contained a sparse subpopulation of CD34+/CD10+ elongated telocytes with a higher density in the lunular region and, at this distal level, a change in their immunohistochemical profile, resulting in a progressive loss of CD34 expression. The matrix hypodermis showed CD34+/CD10+ telocytes in their classical elongated aspect, which acquired, especially in the distal fibromyxoid area of the thumb, an oval to round morphology with multiple intracytoplasmic vacuoles. The characteristic dynamic immunophenotypic profile of the dermal telocytes with a progressive distal loss of the defining molecule CD34 was equally observed in the distal hypodermis. The nail bed dermis was thick with a dense fibrous connective tissue. A reticular network of CD34-/CD10+ telocytes was present in the superficial dermis of the proximal nail bed. The mesenchymal cells of the deep part of the proximal nail bed dermis and the entire distal nail bed dermis were CD34-/CD10-. The adult nail mesenchyme is composed of 3 microanatomically distinct regions. Only the thumb has a distal hypodermis rich in mucinous material. The population of telocytes is relatively sparse compared with the fibroblastic population of the entire nail mesenchyme. The concept of onychodermis/onychofibroblasts is not valid. Nail telocytes have a dynamic immunohistochemical profile depending on whether they are located proximally or distally. The CD34+/CD10+ profile correlates with the onychogenic epithelial region, while the CD34-/CD10+ profile correlates with a spatial rearrangement of the nail epidermal bed.","PeriodicalId":501833,"journal":{"name":"The American Journal of Dermatopathology","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Adithya Christopher Godfred, Zachariah Thomas, Dincy Peter, Anjana Joseph, Lavanya Ravichandran, Anu Anna George, Susanne A Pulimood, Pranay Gaikwad, Ramesh Babu, Meera Thomas, Nihal Thomas, Aaron Chapla
{"title":"A Novel Large Deletion in the EVER1 Gene in a Family With Epidermodysplasia Verruciformis From India.","authors":"Adithya Christopher Godfred, Zachariah Thomas, Dincy Peter, Anjana Joseph, Lavanya Ravichandran, Anu Anna George, Susanne A Pulimood, Pranay Gaikwad, Ramesh Babu, Meera Thomas, Nihal Thomas, Aaron Chapla","doi":"10.1097/dad.0000000000002657","DOIUrl":"https://doi.org/10.1097/dad.0000000000002657","url":null,"abstract":"Epidermodysplasia verruciformis (EV) is a rare autosomal recessive genodermatosis due to mutations in EVER1 and EVER2 genes. The genetic profile of Indian patients with EV has not been previously studied. This report describes the clinical presentation and molecular analysis of a family with EV. Using genomic DNA from two affected probands and healthy controls (two other siblings), conventional polymerase chain reaction (PCR) was conducted with novel primer sets designed to amplify the coding and splice-site regions in the genes EVER1 and EVER 2. This revealed no amplification with a primer set for exons 16 to 18 in the EVER1 gene of both the probands. Subsequently, long-range PCR spanning the length of exon 15-20 and next-generation sequencing demonstrated a homozygous deletion of 2078 bp in the EVER1 gene (EVER1:c.2072_2278del). Screening the family revealed the same homozygous deletion (similar to index cases) in two other affected siblings. The parents and two asymptomatic siblings were heterozygous carriers for the deletion while one healthy sibling was negative. These results were validated with Sanger sequencing. This deletion in exons 17 and 18 of the EVER1 gene results in a frameshift, followed by a premature termination resulting in a severe phenotype. The identification and validation of this large deletion was detected using stepwise amplicon-based target enrichment and long-range PCR, respectively. In this family, this simple strategy greatly enhanced genetic counseling as well as early genetic diagnosis and screening. However, functional assays and larger studies are required to characterize and validate the genetic diversity among Indians with EV.","PeriodicalId":501833,"journal":{"name":"The American Journal of Dermatopathology","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140593383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Case of CD4+ T-Cell Lymphoma With Gamma-Delta Phenotype, Incidentally Manifesting in a Wound Debridement Sample.","authors":"Paige E Adams, Vida Ehyayee, Aadil Ahmed","doi":"10.1097/dad.0000000000002695","DOIUrl":"https://doi.org/10.1097/dad.0000000000002695","url":null,"abstract":"We report an 85-year-old male patient with a medical history significant for psoriasis who presented with a thigh wound that expanded slowly over the course of 9 months. The patient was previously treated with amputation of hand digits for osteomyelitis. Histologic examination of the tissue sample revealed a broad ulceration with large areas of necrosis extending into the subcutis. The edge of the specimen also revealed a nodular lymphoid infiltrate in the subcutaneous adipose tissue composed of atypical cells. These cells were only positive for CD3, CD4, and T-cell receptor (TCR) delta stains . The Ki-67 proliferation index of tumor cells was about 70%. The tumor cells were negative for CD30, CD8, CD56, TCR BF1, granzyme, TIA1, CD123, and Epstein-Barr encoding region (EBER)-ish stains. A diagnosis of gamma-delta T-cell lymphoma was made. Further imaging showed regional lymphadenopathy. The patient was started on mini-CHOP and filgrastim; however, the patient died within 1 month after the diagnosis. This is an interesting case of gamma-delta T-cell lymphoma that was incidentally diagnosed on a chronic wound. In addition, it showed a CD4+, CD8- phenotype that is exceedingly rare for T-cell lymphomas with gamma-delta phenotype.","PeriodicalId":501833,"journal":{"name":"The American Journal of Dermatopathology","volume":"207 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140571027","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Spiny Keratoderma: Clinical and Histopathological Findings in a Series of 3 Cases.","authors":"Ailish Hanly, Noel Turner, Christine J Ko, Gauri Panse","doi":"10.1097/dad.0000000000002705","DOIUrl":"https://doi.org/10.1097/dad.0000000000002705","url":null,"abstract":"Spiny keratoderma is a rare entity presenting with minute keratotic spines on the palms and soles. Spiny keratoderma can be inherited or acquired, and the acquired form may be associated with underlying malignancy or systemic disease. Clinically, the differential diagnosis includes other digitate keratoses on acral sites, most notably arsenical keratosis, filiform verruca, and punctate porokeratosis. Biopsy findings typically include a column of parakeratosis overlying a diminished granular cell layer. In this article, we present 3 cases of acquired spiny keratoderma in patients with various systemic diseases, but no underlying malignancy.","PeriodicalId":501833,"journal":{"name":"The American Journal of Dermatopathology","volume":"34 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140570985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Case of Eruptive Xanthoma With the Lipidization of Keratinocytes.","authors":"Kai-Yi Zhou, Li-Wei Ran, S. Fang","doi":"10.1097/DAD.0000000000002708","DOIUrl":"https://doi.org/10.1097/DAD.0000000000002708","url":null,"abstract":"","PeriodicalId":501833,"journal":{"name":"The American Journal of Dermatopathology","volume":"23 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140742338","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Immunohistochemical Expression of Angiotensin-Converting Enzyme 2 in the Skin of Patients Affected by COVID-19.","authors":"Asmaa Gaber Abdou, Mona Fayed, Azza Gaber Antar Farag","doi":"10.1097/dad.0000000000002498","DOIUrl":"https://doi.org/10.1097/dad.0000000000002498","url":null,"abstract":"After many recorded cases of acute pneumonia of unknown cause, the World Health Organization announced COVID-19 as the start of a new coronavirus disease pandemic in 2019. Angiotensin-converting enzyme-2 (ACE2) is reduced by a protease known as transmembrane serine type 2 in the host cell, which then activates the S protein of SARS-CoV-2 regulating coronavirus entry into the host cells.","PeriodicalId":501833,"journal":{"name":"The American Journal of Dermatopathology","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138693328","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A Case of Superficial Papular Neuroma: A Rare Neural Neoplasm.","authors":"Shuji Suzuki, Takuya Fukumoto, Tsubasa Hiraki, Lynne J Goldberg","doi":"10.1097/dad.0000000000002553","DOIUrl":"https://doi.org/10.1097/dad.0000000000002553","url":null,"abstract":"A case of 67-year-old male patient with superficial papular neuroma (SPN) on the occiput is reported. This is the second report of SPN and the first with clinical images. Histologically, in the superficial dermis and periadnexa, the specimen exhibits a nodule of bland spindle cells with an S-shaped and spindle nucleus, surrounded by eosinophilic collagen fibers and scattered mast cells, which forms focally peripheral nerve-like structures. Lichen simplex chronicus-like changes are observed. Immunostaining result revealed that the tumor cells are positive for S-100, neurofilament, collagen IV, and CD34 but negative for Melan A, epithelial membrane antigen, and glial fibrillary acidic protein. Histological differential diagnosis includes prurigo nodularis, neurotized nevus, benign peripheral nerve sheath tumor, such as neurofibroma or schwannoma, a type of neuroma, such as traumatic neuroma, mucosal neuroma, and palisaded encapsulated neuroma, or a type of neural hamartoma. A careful histological investigation will enable dermatopathologists to make a diagnosis of SPN.","PeriodicalId":501833,"journal":{"name":"The American Journal of Dermatopathology","volume":"5 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138693327","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}